Cafe Scientific, Southampton, UK, past talks

Some details on past SWA science cafe talks in 2010 , including transcripts of talks and Q&A
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Some details on SWA science cafe talks of mid 2012
Some details on SWA science cafe talks of end 2012, including transcripts of talks and Q&A
Some details on SWA science cafe talks of early 2013, including transcripts of talks and Q&A
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Some details on SWA science cafe talks of late 2013, including transcripts of talks and Q&A
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Latest update of this file 04 January , 2014
Some summaries etc of past talks held at the venue, The Southwestern Arms (upstairs room) , 36 Adelaide Rd, St Denys, SO17 2HW
Some hosts are not alowing remote linking now , so to view a "forbidden" picture you have to right click on the mouse and select "view". Not verbatim, and there will be homonyms, transcription, transliteration, typing and spelling errors and misattributions in the following write-ups. Q&A , grouped under one "Q" or ? terminator tend to be dialogue with / multiple questions from one enquirer. ? for unheard / masked words , ??? for phrases.

Monday 13 May, 2013 Prof Chris Rhodes : What happens when we run out of oil. 3/4 hour talk, 3/4 hour Q&A, 35 people A petrol pump from a few streets away from where I live, garage didn't fail from peak oil, it just went out of business. 90% of the world's transportation depends on liquid fuel . So does just about every other aspect of our lives. If there is going to be a slow down of production of crude oil then it will change human civilisation to some considerable degree. The world use of energy over time , 1965 to 2005. The top curve at the end of that 40 year period, humanity was getting through about 2.5 times the amount of oil at the start. Twice as much coal, 3 x as much gas and the rise of the nuclear industry. By the end of that 40 years, 3 x as much energy than at the start of it. And that is just for a doubling of the population, tha tis more energy per capita. From the BP statistical review, the latest info. The lion's share of energy use by humans comes from cruse oil, coal is a close and rising second , then natural gas then avbout 5% each of nuclear and hydro and less than 2% in the form of renewables. So about 90 % of our energy comes from fossil fuels. The "good old days" the Humphrey Jones gusher in Texas a century ago. Then all that was required to do was make a hole i nthe ground. An oil well doesn't only contain oil , gas under pressure , a hydro-static pressure of water pressing against the oil. Once you drill through the rock at the top that is holding it all in place , then the pressure forces the oil out. In those days you only needed to expend one barrel's-worth of energy to get 100 barrels in return. Now the figure is probably somewhere between 10 and 20 , payoff falling all the time. We have to work harder to ge tthe oil out, for various reasons. 30 billion barrels of oil produced a year, 84 million barrels a day. Major producers are Saudi-Arabia and Russia , between them about 1/4 of the world oil. Different designations of oil , according to its viscosity, heavy or light, sweet or sour depending on its sulphur content. The sweet oils are favoured as cheaper to process to fuels. The light and sweet oil is the easiest to refine to petrol. Lots of it still in Saudi, Iraq and Iran. Oil is not a single material - an exhibit at the Norway Museum of Science and Technology . The differecnt Norway fields are not that far apart from each other , geographically , but adjascent fields pull up entirtely differnt kinds of material, some very light some you can handle as they are that viscous, like tar macadam. Entirely different molecules and different properties. Petroleum is far from being a simple substance. Much of the oil remaining is the high S variety. Needs very costly processing and not all is recoverable. People often make claims that they have so many billion barrels of oil , discovered somewhere. And it will turn out that a majority of that may not be recoverable at all. People say there is something like 3 trillion barrels of shale-oil unde rthe USA but actually its not shale and its not oil, it contains an organic material called Keragin ? a solid that you have to use a lot of energy to heat it up to produce a product that in any way resembles crude oil. Very poor return of energy on energy invested. Oil is the raw chemical feedstock for plastics , chemicals , pharmaceuticals, computers, telephones etc. Try looking around a room and find something that does not depend on oil. The bricks of this old pub have probably never seen any oil, but modern bricks would have. We're totally dependent on crude oil and the rider is that without oil and natural gas to make fertilisers, we couldn't grow any food. Modern industrialised farming , a field of soya being harvested by an array of combine harvesters in Brazil. The fuels for them is refined oil, then transported around the world again using fuel. The great cloud of dust kicked up by them , topsoil. We're loosing topsoil at the rate of about 1% per year. If we could get around the shortage of resources, we are running out of land. The UK imports something like 40% of its food and then moved around the country. UK food production uses about 1 million tons of oil for tractors etc. Transporting food in the UK uses about another 3 million tons of oil and about a fifth of that is for car journeys to shops to buy it. Add it all up and about 7 million tons of oil per year to feed Britain. About one sixth of all the energy used in the country yearly, ie farming, packaging , refrigeration, transport. 5 million tons of oil for plastic is used in Britain every year , much of that for food industry packaging. Total oil for transport in the uk is about 60 million tons per year and about a fifth of that is for planes. A man in 1956 , people should have listened to a bit more but they didn't. A geo-physicist , Hubbard, working for the Shell developement Corporation in the States. No computers or analytical models then. He had an expert system . He looked at oil production and the peak discovery year , the year when more oil was discovered in the USA before or after , was 1930. Forty years later the peak in production would happen and everyone laughed at him . Because in 1956 Texas was awash in oil. He was spot on , production peaked in the USA in 1970 and now the US imports about 2/3 of its oil. So if Hubbard is right for world production and peaking in 1965 , add 40 and then 2005 , we're not running out of oil. But light sweet crude oil production did peak in 2005.
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We're not scraping the bottom of the barrel but going that way, more of the heavy crude , high energy to deal with stuff. In 1980 we started using oil faster than we found it. So now for every 4 barrels of oil we use , we only discover one new barrel. So like spending your money 4 times faster than you earn it. Of 98 oil producing nations , 2/3 are now past their production peak. Saudi is still ok , Canada seems to be doing ok as does Venuzuels. But Russia , America , the North sea (peaking in 1999) is a global phenomenon. Energy Information Administration , part of the USA Dept of Energy, so not some crank outfit. Produced in 2010 , the analysis reckoned that about 2013 there should be a peak in oil production. Once oil production is peaked then there will be a terminal decline and by about 2013 only half our current production of oil. They euphemistically identified the gap as "unidentified projects"
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A big hole, where is it going to be filled from. The French equivalent, the Paris based , International Energy Agency , world energy outlook published in 2012
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Projected oil supply out to 2025. The bottom set of bars , actual oil being produced at the moment. So by 2035 producing half what we are producing now. Fields yet to be found - they know where they are but unless the price of a barrel goes up to 130 or 150 dollars , its not worth it. Natural gas/ liquids are not the same as petroleum , diferent molecules. You can't refine them into petrol, you can use them for other purposes. Other unconventional - coal to liquid, tar-sands, like tight-oil is what people generally call shale-oil, recovered from fracking. They don't believe its going to take over the world. It will be fairly steady. So if you add the light tight crude oil , unconventionals then probsably about the same scenario as the USA counterpart of this agency - within 20 years about half the amounft of crude oil than at the moment. And no obvious means to replace it. So we need to find alternatives to oil. We're running out of the cheap and easily won stuff. Need to find alternative fuels, carbon feedstocks for industry. The other suide ot it , burning oil contributes about 3 billion tons of carbon to the atmosphere, about 1/3 of all emissions that can be blamed on humans, and the issue of climate change. So as the oil runs out, we will be releasing less CO2 is one argument. We are a global civilisation that is entirely dependent on moving goods and people around. Without some alternative then a fairly difficult situation. People talk of hydrogen as the perfect green fuel. In reality it is . Mix hydrogen with oxygen from air in a fuel cell , produces electricity to run a green car , pure water drips out of the exhaust. But you can't mine hydrogen out of the ground. It has to be made. Most of the hydrogen is made from steam and natural gas but for every 4 lots of hydrogen you get one lot of CO2 . Most of the hydrogen, presently , is used to make fertilisers . Used i nthe oil industry for hydro- cracking, hydro-desulphurisation . The process whereby you get the sulphur out of the sour heavy oils. You have to do that or you can't really process htem . Capturing the CO2 , CCS, would cost about 1/3 of the energy of the hydrogen that you get out at the end. This also applies to coal-fired power stastions. If you want to adopt CCS, for every 2 coal-fired power stations you need to build a third one to cope with the C emissions from those 2 and itself. I think that is why noi government has taken it seriously, so far and maybe they never will. An alternative is water-electrolysis, pass electricity through water, split into H and O , but where does the electricity come from. To generate enough H in one year , to match the 60 million tons of crude oil that we use to make our liquid fuels at the moment would need 61 GigaWatts of power, assuming you can use H at twice the efficiency of petrol. So 61 new standard sized power stations. So if these were coal or gas fired , for the UK, that would treble our C emisions. Its seriously suggested that we could use nuclear power as CO2-free, when they are running, a lot of CO2 for making the concrete etc of them. But you still need 61 of them. How many can you bring on in a year, say 5. It takes 10 years to go from drawing-board to producing electricity. So 20 years time, by then we will have lost about half of our conventional oil production, so a loosing battle, tiomewise. There is only one factory in France that can make the new generation reactors, making 2 per year. For any of these, requires a huge amount of manufactuiring capacity, True for solar or any other innovation. Its not just the UK thast would want new nuclear generation, everyonne will want them. Perhaps use renewable energy from wind-power, we still need 61GW. So take the biggest available wind turbine, 5Mwatt. Rated capacity is not what the generator gives out. More an average output, due to wind speed etc, usually about 30% capacity factor so about 1.5MW on average. So need about 40,000 , so put them in scale. They would be clustered rather than evenly around the English coastline. But if they were , the coast about 2500 Km around , so placing the recommended 10x rotor diameters about , so 1.25km , a single band would be occupied by 2000 turbines, so for 40,000 would need to be 20 turbines deep, about 15 miles wide around the entire coast. How quickly could you supply all this. Assume making and installing one a day , it would take over 100 years. Another aspect is rare-easrth elements. There are shortages . Very important in wind-turbines and hybrid cars because they make very powerful magnets . A rare-earth magnet can have 10 times the strength of an iron magnt. So for the same magnetic field a tenth of the weight. But for each Mwatt of wind power you need one tone of rare earth element, 1/4 ton of neodymium , so about 135,000 tons of neodymium . That is over that we need currently 5 times the rare earths currently in proiduction , to meet existing targets because we've signed up in Britain , to the EU to provide a lot of renewable energy in the form of wind power. I do really wonder if we can meet our C emission targets. The Toyota Prius contains about 1Kg of neodymium , 10 to 15 Kg of lanthenum for the battery. So hybrid cars need a lot of rare earth materials. The joke rin the pack os that practically all the rare earth elements in the world, at the moment, come from China. China itself is undergoing unprecedented industrial expansion and need all the energy it can get its hands on, including renewables. They are holding back on rare earth exports for their own purposes. So for the UK and other countries to meet the targets then we need to find other sources. A field of sugar beet in Norfolk. Grow your beet, extract the sugar, ferment it , separate the ethanol from the water , via distillation or membrane technology . the UK has only about half the acreage required for this, even if we stpped growing food crops , only 50 % of our fuuel via this process. Its even worse for bio-diesel . Being charitable , in assuming we convert all our engines to diesel , so less fuel required. We would then need about 400,000 sq km of arable land but we still have only that 65,000 . So grow rapeseed only, stop food production , we'd only meet 1/6 of our current fuel requirement from crude oil. At best land-based fuel crops are never going to make more than a few percent. We already import about 40% of our food , we should be growing more of our own food rather than turning it over to bio-fuels. Water use. If you look at water use in Litres/Megawatthour , for extraction and refining of oil you're in the tens or low hundreds. For corn and soya beans for ethanol you're up in the millions. So not only pressure on land for one kind of crop or another , huge pressure on the amount of fresh water. NMaking bio-diesel from algae. Its green because it contains chlorophyl , undergoes photosynthesis , absorbs CO2 from the atmosphere. Then process the algae into biofuel. This has recommendable points to it . Once you get the alga and filtered , it is still incredibly wet. The energy required to dry it before further processing, will be pretty large. Advantages are it can be grown in tanks that yield of about 100 tons per hectare, compared to corn or rape seed of about 1 tone per hectare. So if you could have 4,000 sq km of these tanks , that would produce your 40 million tons of biofuel. We could run the UK on about 1.5 % of the land area. Huge amounts of engineering and at least 10 years off. You don't need good crop growing soil, you can stick the tanks anywhere, so no compromise with food production. You don't need to use fresh water either. It runs well on saline water and waste water , and so no competition with general water requirements. You can feed your alga what is usually rubbish, agricultural run off water and sewage water contains a lot of N and P and avoids the otherwise artificial input of N and P , actually cleaning the water which would otherwise cause algal blooms. Cleaning this water artificially is very expensive and difficult but if you can integrate this into one collective, would be impressive. Tanks with alga growing in them, waste water treatment plant, fossil fuel plant emitting CO2. You feed your C emissions and your polluted water to the algae , you get rid of 2 problems and solves a third one, which is what to do to replace the crude oil. Fracking. All very controversial. Take a fluid that is largely water containing all sorts of other materials like sand which acts as a ?, it also contains various chemicals acting in various ways according to the situation. You pump the fluid down at 15,000 psi .You have some rock that contains some gas or oil bu tthe rock is impermeable. The pressure is high enough to crack the rock open so what it contains can flow out. A very energy intensive process. A single well can produe a million to 5 million gallons of waste water. This water contains not only the original fracking fluid but also the likes of Radon . These processes are done at depth and in some locations you will have radioactive materials and all sorts of other things. You can never know what will be in the mix at the end of the process . To meet our projected targets of 2035 we'd need to dril about 1 million new shale gas wells. There has been something like a million fracking operations conducted across the world already and about 9 out of 10 oil and gas wells are stimulated by fracking processes. The production drops , so they can be jigged-up by fracking . Not a new technology , been known of for 60 years. There is a big concern about contamination of water . Video clip called gas-land? a guy in the USA goes to his kitchen , turns on the water tap and he can ignite the gas coming out of it s its so heavily contaminated with methane. A University of Texas research showed there can be methane in the ground for other reasons than fracking. Old timers will say they were igniting the gas here long before they were fracking. A complex issue. I don't think the claim that the USA has enough gas to last a hundredyears , stands up. Look at the figures and its more like 20 years worth. Can solar, wind , geo-thermals save us. Yes, but not entirely. What we get out of these sources is electricity. Looking at primary energy use it is about 1:1:1, for electricity, primary fuels poarticularly petroleum , oil for heating etc. Even if we could make all our electricity from renewables we still have to somehow to provide the equivalent of liquid fuel and the heating. Liquid fuel supply is declining at about 3% per year. Lests say by 2030 there will be this big holeof only half the production we have now. There is no easy way around the transportation problem . 34 million cars on Britains roads at the moment, powered by liquid fuels. I don't think there will be 34m electric cars any time soon. Personalised transport will have to go for a Burton. The sensible way to move people around using electricity is light-rail and tramways. There are limitations to these various elements. I've touched on rare earths but other materials like indium, cadmium , telurium etc which are critical to solar power and electronics generally. They are called hitch-hiker elements , meaning they are not extracted in their own rights. They are side extracts from the mining of other material such as copper, iron , aluminium , zinc etc. To ramp up a lot of the renewable energy resources anyway , we would need to find alternative and deliberate sources of these other elements. It seems unlikely that we will be able to replace oil , in the enormous quantities that we use today. We can't solve the supply problem from the supply-side so we have to start to look at the demand side. Looking at the available oil and all our uses for it. It looks like that in 20 years we will have had to cut our liquid fueled transportation by maybe 70% . In effect likely a return to a more localised society. A process called Transition. Because we will no longer be able to move food around the UK. let along bring in from abroad at the level we do now, about 40 %. We will need to produce at a much more local level. Yes electricity for tram transport but we also must not ignore the foot and the bicycle. A third-world basket maker , himself and his family taking under his own steam on an overloaded bike to a local village. Producing more local food, materials, and the things that we actually need, to cut down the amount we need to import from elsewhere. Need to work closer to home. I live in Reading a well known commuter town. You think , the people who live in Reading commute to london but an almost equal number commute into Reading from London and surrounding areas to do high-tec jobs. So perhaps reskill the Reading people to do the Reading jobs an dthe London folk to do the London jobs , would save alot of energy. No mor echeap foreign holidays. Last time I came here was to hear a talk on peak phosphate by Dr James Dyke . Modern agriculture depends on artificial fertilisers , particularly rock phosphate. There is evidence that it will peak in 2030 . I reckon it won't be that bad but there will be an issue some time this century. farming is dependent on synthetic N fertilisers from natural gas and fresh water. There are techniques like perma-culture which enable you to gtrow on a small scale but very effectively, with minimum inputs. No good for mega farms with 20,000 pigs or whatever. The future world will require more recycling and capture of P , N , composting human waste etc. The one-time use of everything is incredibly wasteful and will not be viable into the near future. I think a realistic future will not be where we've thrown away all our technology but producing on a much more local level. What if we don't do anything at all.
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Up to 2005 line his history in this 2005 slide, beyond is prediction. The red curve is the production of oil and then the first of the oil shocks , a slump, in 1973 when the arab oil producing nations decided to make a show of strength against the west. They reduced the production of oil by 5% and the price shot up 400%. A wake-up call and the west brought on some interesting and useful projects. When the cheap oil came back ,there was no longer the incentive. The aquatic species programme where they grew algae , to lead to fuel, that got shelved as considered too espensive. The second shock was the Iran-Iraq war end of the 1970s, then Gulf War , terror . Then we have price spikes, profitering , financial markets collapse , unemployment, recession chilling familiar prediction those few years on. So a not too slow descent into chaos and mayhem if we continued as business-as-usual. The elephant in the room is population. 50 years ago there was less than half as many people on the planet. Our use of resources is not a direct relation to the number of people on the planet but people of developing coutries are aspiring to a consumer lifestyle . The western consumer lifestyle is unsustainable even in the west. This is the cliff that we are trundling off. Assuming a couple of trillion barrels of oil are to be had, altogether, you can make some guess as to what the decline rate of oil use will be. Population from the WHO of 9billion people by 2050 , who knows 12 billion by the end of the century this plot is not indicating that. The population in this prediction will peak at about 7,3 billion. I've seen various analyses and they're not all as Draconian as this , but they all seem to predict a population peak sometime this century. Then it will fall, perhaps 1/3 the number now, at the end of the century which some reckon to be the carrying capacity of the planet. We are living ona planet with finite resources. A bit like bacteria growing in a petri-dish. Only so much food available to them so you get your S-shaped curve. Whether bacteria or humans, with finite resources, something has to give. Its likely to be limitations in resources that will determin the peak. A happy ending - transition towns. Aim to achieve resilience etc. Driven by a belief that the elected leadership will not sort out everything for us. What can we do at grass roots level in terms of food, materials production etc. A great deal you can do. Insulate your house properly saves about 20 % of our energy. If you start along the line of thinking that you are going to have 5% less energy per year then you do things differently . Sustainable jobs. Of those 70,000 from Reading to London every day what sort of jobs will they be doing in 10 or 20 years time, will those jobs even exist with say global companies , probably not. Perhaps reapplication of practical skills and a total rethink of how we live. Quite a challenge. I quote Charles Kingsley a clergyman and uni professor a commentator on the human condition . Effectively he said that we act as though what we actually need , is lots of stuff and what we really need is a reason to get out of bed in the morning , in modern parlance. From all the previous it looks like game-over , but I think there is real optimism and real opportunities to be had in this time in hand. Q&A Q: No mention of fusion power No one has so far got more energy out than they put in , so far noone has passed the break even point. There are other designs like inertial confinement fusion , using high power lasers to compress the target , they reckon they will do better with that . I can't see that we will have fusion powered sources on the time scale of these present problems. Its not that clean , still produces radioactive waste. You're exposing the containment to high energu neutrons , so not as clean as people would think. Even if you had fusion what you wouldn't solve because of the liquid fuels crisis which is what peak oil is, when they run out what is their replacement. Even if you had fusion you cannot totally electrify your transport system. No chance of 34 million electric cars quite soon which require all those exotic materials which are close to peaking also Q:What about using electricity to produce hydrogen and use in engines as you do petrol? Probably a better way of doing it. You still need the huge electricity infrastructure . You have a distrubution problem then , getting the H to locations as well. Petrol stations wouldn't suport H, would that be a reasonable route? Are you thinking about generating at a local level rather than a massive distribution system. I would not expect H production in people's garages or even at village level . There may be something in what you say. But you still need an enormous number of wind turbines or solar panels if from green sources. This is where fusion would come in , ideally. Its always been on the back-burner no one sems to have put real effort into it. If you compare it to someone like Intel , they can design and build a massive manufacturing complex in 6 months. Around CERNE they have spent 8 years on the new IATA building a big hole and some footing but nothing like a complete building yet. I don't think anyone really beleives that fusion will come to our aid anytime soon. Q: There will almost certainly be energy rationing in the future , what impact do you see that haviong on society? Perhaps a wartime like situation and petrol rationing. I think that will be the only way. Q: I think you're painting far too a rosey picture. Gibbon ? and his 3 killer facts, 2 degreesC, 565 Gigatons of CO2 we can release without exceeding that and 2800 Gigatons of CO2 that will be released if we burn all the proven resources. We cannot even run down that declining curve without exceeding 2 deg C and then who knows what. An even greater threat to civilisation . I think peak-oil will hit us first and then future generations are going to fry as a result of that. 2030 is pretty soon. By 2050 perhaps a toss up between the two. We will still see pretty drastic effects with 0.8 deg C We won't know until the experiment has been conducted in reality. Q: The situation is so depressing perhaps we will have people sliting their throats. With economists we can run politicians and between them perhaps form an alliance. How much of it is an economic and political problem as opposed to a scientific problem. Is there anything else that scientists could do . Are you referring to peak-oil deniers or climate-change deniers? All sortts of deniers. In the American Republican party there are people that will deny virtually all the science. Then the more moderate ones say everything can carry on as it is. A range of deniers across that spectrum. Is the science all there for people to see I think the science is all there but it needs to be presented more widely. The governments of the world are clearly well aware , from advisors etc, they do know what is going on . There isa n obscure website of the UK government that does say something about peak-oil but you don't hear Mr Cameron shouting about this. Governments don't want to make a fuss about it. How politically popular is petrol rationing going to be. Its very tricky territory . Pretend things are ok and they will get re-elected. Q: I was surprised about your statement that population would peak and start dropping quite dramatically. I would have thought it would grow and level out. Even the WHO latest analysis seems to be indicating a peak, perhaps not as soon as 2025 but certainly 2050-2060. The mechanism could be rather unpleasant , starvation, disease, wars over resources . Population control is a very sensitive issue, very difficult to impose on people. When Russia went through its fall of communism changes the population fell because there were terrible hardships and shortages. I think that will be the case across the world. Q: Why is population such a delicate issue. I've grown up over a time where its become culturally unacceptable to be racist or even a smoker so why is it not culturally unacceptable to have lots of chidren? I don't understand why we have not had incentives to have less children . Its part of some religions , to have lots of children . It might be perceived by say a parliamentary figure as discriminating against a certain religious faction . Difficult, it is the elephant in the room. A lot of estimates reckon the carrying capacity of the Earth is 2 billion, what it would be if we did not have all these fossil fuel inputs and so forth. We would not have these problems. There is a group calle dPopulation Matters , Jonathen Porrit gave a talk in Winchester a few weeks back . It is about prejudice, eugenics and things like that . Q: What do you make of Transitions and the like? Its a positive way to address out resource issues . I don't know if we can pull it off entirely but the more we can do at the local level then the less demand we have on external inputs. That has to help in all sorts of respects. The biggest issue is that we won't have so much transportation available to us in the future and that will change all sorts of things. That drives the local dimension Q: Just to go back the population thing. Chuina had the one-child policy and that is now under great pressure because of so-called affluence and a lot of that pressure comes from the West . I beleive the population of China is growing at about 0.6% ,half that of the USA say. This is part of the consumer life-style, you want mor estuff , you want more kids too, the freedom to hav ethe things that the US or Europe has. Understandable but our way is not sustainable either, not a good role model. Q: The Bilderberg group is meeting in June , do you imagine this would be on the discussion agenda, peak oil? I'd be surprised if it wasn't , though I don't know. Q: Maybe democracy is a problem. If you want to get elected , you cannot say my government will cut the use of private cars , stop holiday flights, and restrict foodstuffs to English grown only. You wouldn't be elected. You wouldn't . I was interviewed by George Galloway on his radio show a few years ago and he said precisely that. That is in a capitalist economy, you cannpt make these legislations. In a command economy you could. So its not in our democratic structure to do this. It would be perceived as fascism to impose such controls. Q: So they have to do it surrepticiously by forcing up the prices ? its the only thing that changes our actions. The driver for change , such as when it costs 3 quid for a litre of petrol , that will change behaviour considerably. It already has, in that people are now driving fewer miles than they used to . Q: The cost of fuel is pretty inelastic, we are addicted to it , and will just keep paying more . But there does come a point where people who had a large car will go for a smaller ans only become more so like that. The price of fuel has gone up something like 4 times in the last 10years , that is reflected in costs at the petrol pump. Some people take the view that as oil has gone up from 25 USD to 100 USD a barrel , why has it been flat, why haven't they been pumping mor eout of the ground. Because they cant , they're at the limit now. If they could have done they would have done, they're not charities . I think we are at the ceiling. To maintain that rate of production needs all the new kinds of technologies which all cost a firtune . The Keynsian economists say , if the price goes up then you can find more of a commmodity . I don't think it fits in with the idea of peask oil. There are geological and technical limits to it. Its not what is down there, the size of the tank, its the size of the tap. Its how quickly it can be got out. Q: A thought experiment, assuming very roughly that at peak oil we've used half of it . If tomorrow some miracle happened and we got free enregy, fusion perhaps, do you think we'd survive on the liquid fuels tha twe have left. Or are we at a crisis point even if we suddenly got free energy and free water. Because our transport infrastructure is entirely built on liquid fuels then a problem. It would take a long time to come up with a parallel transportation system that was all electric for example. Within the society and civilisation theat we have then quite difficult. If by transitions type structures we can build up transportation based on resilience , sustainability all very good. But I'm not convinced we can do that at the level at which we can stay . Our future may become sustainable but it will be a lot lower energy job. Using less stuff in the future. A huge shift in perception as much as anything else. THere is a part of Transitions that is to do with hearts and souls , basicly how we will get our heads around the whole concept. The new order without slitting our wrists as the man over there said earlier on. Q: Something like 30 or 40 percent of the jobs are only there to support consumerism . I said of those 70,000 Reading commuters every day, those jobs won't exist in the future. What will they all do. On allotments, planting fruit trees , I don't know, Certainly for practical skills , carpentry, permaculture , all sorts of things but it will all be a different way of living. I look a tthe university system and the whole eductation system . We seem to be educating a generation for a status quo future which iss differnt to what they are likely to find. It seems a woefully neglected duty, completely unfsair. So when will the shit hit the fan? I think by 2020 things will be wobbling quite a bit. By 2030 , erm. Do you watch Aljezerah . The other night they were interviewing an american academic . The interviewer asked, what was Iraq about? , it was about oil. What was Afghanistan about? they don't have any oil. Its where they are placed next door to Iran , Khazakstan, etc surrounded by oil. She was explaining the point of Afghanistan was for building military bases . So I think to myself is this the map of world war 3. Something of that magnitude . Say there was military action on Iran , and the Strait of Hormuz was shut , about 1/4 of UK gas goes through there from Qatar. One of those tankers contains enough gas to keep Britain going for 6 hours and they have to arrive continually. Any interuption in supply . Germany has about 10 weeks supply of gas, We have a couple of weeks. A month or 2 back and the cold weathger we were using 370 million cu metres of gas pe rday , 100 million more per day than normally for that time of year. It was touch and go, They reckon that on the day that Margaret Thatcher died , whether the lights would go out. We are that close, we are so vulnerable. North Sea production has fallen considerably 1.3 of what it was 30 years ago . So importing oil and importing gas for the same reason , for gasfield decline, importing food. It was worse with the food production issue during world war 1. Which is why the convoys were so vulnerable. During world war 2 the nation produced a much bigger proportion of its food. Heavy use of fertilisers, heavy tillage,heavy machinery which in the USA caused the Grapes of Wrath situation made us much more productive in food. But how viable and sustainable is that likely to be without hte cheap oil. Its not , a huge game changer. Has anyone produced a working large C capture and storage facility, say 1Gwatt? Not to the best of my knowledge. Are there serious technical difficulties or just a matter of scaling things up? I think the main problem is the expense. If you were makingt electricity in coal-fired power plants , for 2 you'd havre to build a third to provide the energy to power the C capture of the first 2 and itself. I think that is the reason that no government has seriously adopted it so far. As a technical exercise it could be done , but the best so far is taking th e CO2 and pumping it down into old oil wells. A lot of the CO2 in the oil industry is reinjected asa secondary production strategy. There are differnt aspects to oil production. There is tyhe easy way , when you first strike a well, you dril through and its under pressure, after you've produced about say half of it , the pressure drops . So you have to keep the pressure up , which can be done by pumping gas , can be CO2, or methane that came up with the oil before. The tertiary recovery is where you increase the fluidity of the oil , generally by heating and most common is by steam injection. All these extra procedures cost a lot more energy, that is why the energy return , across the world , is falling. A Prof Charles Hawe? in the USA worked out that a society like ours complex and industrialised needs an energy return on energy invested of about 10. For agrarian societies maybe about 2. In between would be like the Victorian times and a lot of coal burnt. The return is now coming down to about 10 for oil, for what we require to function as we are. The alga technology sounds too good to be true in a sense. It requires fairly low-tech processes and I see jus tlast week its been scaled up to about an acre sort of size on a commercial basis, and it will work, there is nothing wrong with the process. Can the output be used as a feed stock for the plastics industry or purely for energy production? You can use algae for various purposes , you can certainly make plastics out of bio-mass and alga is biomass. You can convert the algae of other biomass to simgas? and then you have an established means for making plastics and hydro-carbons generally speaking. It does not have to be for making fuel. Again, its not going to give you the energy return that you get out of oil and natural gas. There was something on the cover of Chemistry World the chemical industry publication and the title was Getting away from Oil. About making plastics etc from lignites , interesting but takes an enormous amount of energy to do it. I think this will be our failing, we will just fall off this energy cliff. There are a lot of very clever technological innovations around , just scaling them up and thats where many of these schemes fal down. If you had 3 practical tips trhat people could do , from the Transistions point of view, easily, What would they be ? Insulate your house, good draught insulation Drive less, try to earn a living without having to drive into London and back Get into perma-culture, using low input methods and good designs , grow as much as you can My 3 critical ones One thing that has come up is food waste, in that we waste a lot in this country, the energy and resiources that go into making them . Is it the Bogoff thats the problem or is it the supermarkets telling farmers , we need tomatoes exactly that size, no blemishes ? Personally I find nothing wrong with bogoffs, I wouldn't buy perishables that were bogoffs ,but 3 or 4 cans of beans for the price of 2 is fine by me? At the farm stage and the overarching control of the supermarkets that the waste was at principally.? In the case of tomatoes ,the farmers cannot even can the "waste" tomatoes as they ar ethe wrong sort for canning. Italy produces the sort of tomatoies that can be canned. Would you happen to know the ratio of wastes from the 2 sources of bogoffs and farm waste? A figure I heard recently was about 1/3 of food crops get left in the fields. Perhaps you can attribute the other 2/3 to the bogoff. A figure I've not been able to lay my hands on is the percentage of commuters who commute to work and they sit at an office at a computer, fax or telephone for 80 or 90 percent of their prioductive time, that could equally be done at home? I was asket that some years ago. I did manage to find a figure but its complicated. Its something like 60% of people who work in offices doing processes that could be done at home. As distinct from the police or fire service say , who have to be out doing something. Its a sizeable fraction. I know the effects of animal farming on CO2 , what about the effects of animal farming and peak oil ? Such as transporting soya from Brazil to here , to feed animals . If you look at just the trasportation issues, that is where you can make your big savings. We'll hav e to as we won't have the affordable oil to move it as we do at the moment. And moving animals from country to country to be killed . aslso? The export of horses over to France for killing there That too . Move over to eating insects? Yes You say that the UK is not going to meet its commitments as far as renewables, so how do you feel about the government giving subsidies for PV cells etc , is it a waste of time? Its not a waste of time, everything helps . When they say produce 20% of out electricity by 2012, not that far off , I don't know that they'll manage that. We seem commited to winfd power for whatever reasoin , even 1 turbine erected a day for the next 7 years we will still be behind the targets. If we'd have done the Severn Barrage then we would have been well on the way then, but not close to that target? A figure of 14Gwatts comes to mind , pretty high. It would certainly cut a hole in it. Decided against it, ironically, for environmental reasons.

Monday 10 Jun , 2013 Dr Ivo Tews Title: Preparing for the International Year of Crystallography Covering the science from the beginnings of crystallography to the more recent successes that lead to the nobel prizes in Medicine and Chemistry, and will focus on the underlying biology of these successes. 3/4 hour talk, 1/2 hour Q&A, 34 people The School for Theoretical Physics, Zommerfelt? , founded the school, a very important movement in Germany. A very influential school for physics. He had a student called Peter Voliber? who had a problem with rays and waves and X-rays, wave theory was new. Electromagnetic spectrum Infra red, radio , micro-wave , visible and much shorter wavelength Xrays. Trying to understand how waves interfere and with a contribution from Maxwell Loewe? . If the waves are getting smaller and smaller , what we could possibly get is the same thing with interference within crystal lattices. What they knew at the time that if you put light waves through slits then you get patterns of dots etc. Some "toys" for the audience to play with, from a market place in Rome , pen-torch size green LED laser pointer with a little grid inside , making an array of dots , and you can turn the grid to change the pattern projected on the wall. Maxwell Loewe thought that a crystal could difract waves with patterns like these laser projectors. From the patterns we could then say what was within the crystals, but no one believed him. Loewe went on to prove this. People believed at the time that there would be too much motion in the crystal and there would not be ordered paterns. So Loewe with his 2 students Clipping? and Friedrik ? went on to show that this indeed worked. X-ray tubes were available since Roengen . A crystal of copper sulphate , got the pattern, and the Academy of Science audience went , Wow!. A dramatic picture, fifth of a series , a milestone of crystallography (CY), in the early 20th century. So xrays can be difracted by crystals. How do we interpret the images. For the copper sulphate crystal , there are copper atoms , oxygen , very complex at the time to know the structure. Another step is required to do this. This is why we now consider the homeland of CY is Britain, because of father and son Bragg, developed the theory. From the pattern to then calculate back to say what is inside, absolutely crucial. A bit like the importance of E=mc^2 is to relativity then the fundamental one for CY A crystal lattice with light from one angle then you get difraction at a diferent angle , angle theta , 2x theta. n(lambda) = 2d sin (theta) The waves coming out are shifted with respect to each other and the formula from sin(theta) , the spacing and the triangle , a simple geometric construction. Sum them up and you get interference of those waves and you observe a spot on your photographic plate. Bragg awarded the Nobel in 1950. That is the physics, now we go into the aplied sciences. We ask the question , what has CY ever done for us!, sanitation, medicine, public order, irrigation, fresh water, roads, education. What does CY help us to understand in biology. The central dogma in biology is that the central information that we have is DNA , the genes, they have to be put across to proteins and enzymes. There is a step in the middle that is RNA, the dogma tells you a direction, DNA to RNA to messenger RNA to proteins. There is transcription and translation. Transcribe the DNA to RNA and translate into proteins. We can replicate the RNA, replicate the DNA , we have viruses that are based on RNA and DNA genomes. We have machinery in our cells to do this. There is reverse transcriptase which is the enzyme that HIV has , so RNA can reverse transcribe to DNA. CY has helped tremendously in understanding these processes. Some Nobel prizes from the endpoints of these processes, the DNA and proteins. With proteins there was another Nobel for Linus Paulin, a CYer in the 1930s. Starting with salts and minerals and then to biological materials. Francis Crick and James Watson and Maurice Wilkins doing the structure of DNA. These go back to photographic images produced by Dorothy Hodgkins, she never got a Nobel prize for this. Paulin also at the time tried to solve the structure of DNA but his proposed model was completely wrong. He did not have access to Hodgkins Xray images. Max Perutz? and John Kendal determined the structure of blood myoglobin and later haemoglobin. This was a time when biology intensley used CY to its best and the first images for bio-molecules using crystals to look at things. We do this because we cannot see the atoms of individual molecules . tHe Nobel prize for Dorothy Hodgkins was for anti-biotics, she discovered the structure of penicilin. In the 1950s a number of things were happening. People who would grow crystals for instance from viruses . Bacterio-phages , plant viruses . Not only CY to view them but then also electron microscopy. A lot of structural knowledge of biological molecules , like viruses. The next Nobel prize winner in this area was Aaron Fluke? . That virus has a genome that is inside like a big staircase and otside are the proteins. It does have a very defined length, a virus that affects plants, tobacco mosaic virus. A numbe rof other viruses we know today the structure of through evolving methods of CY. Since the 80s we now have the methods to do this. Beautiful structures of Polio , plant and avian viruses and a cancer producing virus. A step up now in compexity, recent break throughs . A virus is always a repeat of the same protein and we are now addressing transcription and translation. A very complex process, a number of differenrt proteins put together, very difficult to do. But you can put all this in a single crystal. A picture of the ribosome , the molecule in your cells that make proteins. Molecules coming in at one end , Ductor ? molecules and proteins out at the other side. Remarkable achievements through CY , tells us the inner workings of these bio-molecules. 4 more Nobel prizes , recently awarded. The first in 1988 and the last in 2012. We now look into membranes, the boundaries of the cells. And look at how wwe cross the boundary. The photo-synthetic reaction centre , the information in this molecule shows how to take light and convert to chemical energy. It tells you by yhe location of the chlorophyl molecules , a cascade of these molecules and you have to know the exact spatial arrangement of them to understand how the chemistry works. That is why CY is so important. John Walker of Cambridge, the molcule that produces energy in your cells , the molecule in your mitochondria . We have fantastic machinery that sits in a membrane , with a spinning disc, so always some motion in your cells. Frightening, because it spins quite fast. It spins because you have protein gradients. A difference in charges across the membrane that drives it and produces ATP, the universal currency of energy. So we know how this works. Then in 2003 Peter Ager ? and Bob McKinnon? explained how water crosses cells in a directed way. How we can regulate this in membrane proteins and how ions cross . A student of his , Deklan Doyle? is now at Southampton as a lecturer. The final piece in the jigsaw is the GPCR which is the most important thing, Lekowitz and Kobilka ? looked at these and are pharmatological targets for nearly half of all our medicines. They tell you how a signal is received on the outside , changes the cell inside. So plenty of progress in structural biology . We have other techniques as well, including spectroscopy and other ways of looking. Its so visual, to finally see a molecule and what it does via this technoque of CY. For a while now we've had the human genome, a milestone as well. Structural biologists dream of not only knowing all the genes but all the proteins in cells. That's called structural genomics. Now looking at every dsingle protein. The cell, the genome of that cell, then select a number of molecules , some already in a database , put them together and make the circle, adding to the database. Finally you will be able to explain how the cell works and how all the molecules work together because you know their structure. A flavour of what I'm doing to get data like this. First we purify bio-molecules like proteins or DNA or whatever and we make crystals. Crystals in little drops. The next thing we need , about 2 weeks for them to develop, we have to take them into tiny little loops. About 0.1 micron in length, requiring a very steady hand to do this, a manual operation. I get the crystals out of solution and mount them on an Xray generator. In front of the tube where the Xrays emerge. An image plate or a detector where we take the data. The crystal is frozen in a cryo-stream . You can turn the mount around and do the Xray difraction. Usually this takes overnight , something like 20 hours or so, to se from all different angles. But we have more intense radiation sources these days, and much smaller samples , something like 0.1 micron droplets, tiny crystals of the size 2 microns that cannot be mounted manually. This is where we push the boundaries. We also need a big machine that produces Xrays . The Diamond Synchrotron in Oxfordshire, light source of intense Xrays. We use this quite often. The power consumed is that of a 50,000 inhabitant city. Particles accelerated in an electron gun , run them around a ring requiring bending them. Every time you bend them you get Xrays from them, called Remstrada? . There are 2 ways of producing this A magnet and a beam of particles, perhaps electrons , travel as bunches , bend them from their path and off comes Xrays. synchrotron radiation. You can build dipoles of different magnets and even more intense radiation. Whether at Soton uni or at the synchrotron we have a crystal , shine in Xrays, they get difracted , collect the image. Then the structure is determined by some computing , from this image you can compute that. The maths just works. Very fast detector , chilled down , a robotic unit with 50 crystals sitting in there and mounted in the cold air stram. Once happy with the setup , you leave the room , seal it the lead doors and control everything from the outside. There is the European synchrotron in France , same design, in Grenoble. The new kid on the block is the free-electron laser , the one in Hamberg, costing 1 billion , Soton uni is part of the consortium that runs one of the stations for the UK. If you put ever more intensity of Xrays you will simply destroy matter. You cannot deposit that much light into a bio-molecule . 2 femtoseconds , 2x 10^-15 seconds , 5, 10,20 and after 50 femtoseconds the whole sample explodes. But if you can collect data quicker than it explodes then you can still use it. But you have to be very quick, seconds,millis, micros, nanosec, picosec, femtoseconds. We have technolgy that does that. The amount of data out of such a detector is gigantic, imagine the frame-rate. Some real problems in computing for this, but we can . The proposal in 2000 , being built now and we will operate our station in 2017 . In 2012 a paper came out showing the feasibility of this. For this we will be using a stram of nano-crystals , ever smaller samples and we blast them to bits. So a lot going on in this field. Why the picture of a kindergarten. Kindergarten building blocks and crystals are similar. Go back in history to the 19C and Froegal ? born 1872 a polymath "I could perceive unity and diversity and interconnections in all living things and matter and the principles of physics and biology" This is the age of enlightenment , greatly influenced by Prof Lotze a Swiss educator of the time, Rosseau the philosopher, and Weiss who was a CYer. Rousseau in Emile, how you grow up and look at nature and what you learn from nature . A hypothetical book, but the idea comes from it that everything in nature is good and everything that man touches goes bad. Everything degrades in the hand of man. He tried to learn from nature. He was a CYer , studying with Weiss, at Berlin University. He was given a collection of crystals , at the time of the Prussian kings, they had 75% of all known minerals. Given the task of go and sort it. What system to use to make sense and sort the different shapes and morphologies . Weiss developed what we still use today with our biological crystals , the goniometer ? . Place the crystal on it, and view with a microscope , the shape. The shape on the outside is very much telling you what the shape is on the inside. So classify what they look like, then what is in there , how they could grow and exist in nature . They can make planes inside the crystal and describe what it is built from. Weiss was translating a book from France , CY theory . Froegal then developed these and a book the Crystallography Kindergarten. He made gifts like little balls for entertaining children . These gifts 3,4,5,6 are the building blocks to make crystals with . The idea that a child could discover things was a new concept at that time. The child learnt by experiment. A grat gift that he has given us , the 20 gifts. They don't really exist these days . A number of influential people have been through this kindergarten. Kandinski , you can deconstruct one of his painting sby Froegal gifts. Influential in modern art and architecture. Geodesic domes , Buckminster Fuller went to a Froegal kindergarten. Frank Loyd Wright went to a Froegal Kindergarten, organic abstract geometries in his plans. The Prairie House style in the States, each brick in the wall he drew in the plans. Q&A The mechanics of the freezing. The beam comes in , the beam goes out , manipulating the crystal around, the environment its in , is it an aqueous environment.? You've seen pictures of crystals in solution. We take a solution of a protein or DNA , concentrate it up until it can no longer stay in solution,. So 2 possibilities , it crashes out and destroys itself which happens in about 99% of the cases or it forms a crystal inside the solution. So a crystal is the lower energy state of that molecule . If the concentration is too high , it has to come out of solution but if it preferentially goes to a crystaline state rathe rthan just drying out and destruction. This crystal from a protein is not like you are are familiar with in NaCl , points and atoms and all neat and tidy. It has huge channels and pores in there . Half of the crysatal is water. If you touch it you will destroy it. Movie of droplet with a crtstal in solution , ad a little bit of liquid to make it happier, then a little loop to fish for the crystal that does not really want to go in. Requires manipulation and this particular one has a crack in the middle of it. With luck and skill the crystal hops into the loop. Then you have less than a second to freeze it. With the crystal in the loop it will otherwise dry out very quickly. Vapour pressure from the outside will destroy it. So drop it into liquid H , very quickly, frozen and solid. If you freeze water you will get water crystals and ice crystals will interfere with our experiment. We put a little bit of sugar solution or similar as a cryo-protectant. Freezing human bodies, you can conserve yourself if you have shedloads of money. Put yourself in a liquid N tank and hopefully someone in the future will find a way to revive you. With the sugar it doesn't form ice crystals because the sugar is in the way and it helps the target crystal to freeze in situ. Its amorphous like a glass , glass is a state of molecules that is not really a crystal , you can see through them. Actually forming a glas. So crystals in proteins have to be made, they don't just happen in nature? Many of the things we do in CY goes back to discoveries of crystals. Whales have myoglobin that is crytalline. Open up a whale, take the crystals from the blood , known fo ra long time. Catalase? is another and in your cells you have compartments the so-called peroxysomes? to detox your body. In the peroxysomes there are crystals of proteins , know for 100 years. We could never analyse them but since the arrival of these technologies we can. Some of these are natural. Even membrane proteins , some bacteria at the outside of the membrane , purple patches and they can do photosynthesis and these are crystals, not 3D but 2D in a membrane a regular organised molecule. Actually we use them in electron-microscopy , using electrons rather than Xrays but the same principle. These membrane crystals, can you crush them like copper sulphate crystals and they will crack.? Yes and you can take a piece, and if still ok , you can still use it but you'd rather take the whole crystal. Cracking and mechanical shearing changes the structure , a protein cryatal may not survive. The buffer solution to assist the freezing has to be fine tuned to the conditions, and if not right the crystal explodes, shatters into pieces. Thry're very sensitive. When you produce Xrays from bending particles , what angle do you have to bend to? Not much , forming an end-station as we call it, for the detector as you have to be away from the curve . The lines ar e30 to 50m long and then the hatch/hutch? the lead casement for the experiment. In Diamond has 30 segments . If you change the angle do you get a more intense Xray or less intense? The way we do this is by using mor ethan 1 magnet , a number of dipoles about 50. The intensity now is so much greater that instead of the 20 hours for a data collection now about 20 seconds. The partices are going on a wiggley path and one such manipulator is called a wiggler producing the Xrays. Every time they wiggle back and forth intensifies them. The Diamond is now so intense that we can collect data in less than 1 second. We usually attenuate the beam and use 20 seconds. The upgrade for the new French one in 2018 will produce 3 orders of magnitude more Xrays. We had a meeting in February 2013 where the designer stood up and asked what we can do with these 1000 fold increased intensity Xrays and we do not really know. We will destroy matter very quickly , so will we be attenuating that beram to the level we already have, we don't know yet. The matter wil lbe destroyed, is that because the atoms are ionised? In electron microscopy you can do much the same thing. You can do difraction . What do you think is more damaging to do the experiment with electrons or Xray beam. Photons are the most intense particles , they hit an electron and the electron goes off . There are 2 events really primary and secondary damage. Primary in terms of chemistry creates a radical which can now go on and make reactions inside the crystal. Radical reactions are fast and dangerousRadical chemistry happoens at 10^-10 sec, nothing survives a radical reaction, they attack near enough everything around. These radicals travel and destroy the molecule . We freeze them down to cryogenic temps , 100 deg K, because we don't want these molecules travelling that fast. We want the radicals to stay where they are. It helps us a bit to prevent the secondary damage. But the primary damage to the atoms we can never prevent, the photons will alwys damage matter. Why do you hav ethe blast of very cold air going over the crystals rather than thermally connected via the mount. To construct a way of cooling like this is very difficult. The cold stream instrument costs 60,000 . It vaporizes liquid N, blows it across and blows another stream outside of it that is just slightly faster of completely dry air . What would happen if you just cooled something you would just get condensation and ice which is not what we want in our experiments. You always do these experiments in a linear way? Jus tone end station is 10 million in cost. The designers of these are physicists and machinery engineers. To get your crystals , what we want is the structure we expect to se in a cell. We assume it will have lots of water around it . Your crystals will have some water there and ions . But to get a crystal to form we have to drive the water away. Will that structure going to be really the same as you'd expect in a cell.? A question that is often asked. How realistic is what we actually observe . We are making something that is in your body , taking out of your body and making a crystal. I've givenm 3 examples where we observe crystals in real life. But the molecules we are looking at don't look like that. We have to take the steps through the crystal to analyse the atoms tha tmake the structure. If you look into a cell you have so much liquid . True for a jellyfish with something like 99% water but not true for humans. We use the terminology molecular crowding , thick matter inside the cells. Very little water that is just floating about. Inside the cells there are high consentrations of proteins and diferent molecules , the concentration is near enough the same as we have in one of our crystals. We are doing the process of only taking the same molecules. Can you give us an insight into how the pharmaceutical companies are using this knowledge to make medicines. ? We go back to GPCR , of the Nobel prize last year. 30 or 40 % of all drugs target GPCR. Always this molecule and its elluded structural analysis for so long. For decades people are interested in this. You have molecules flying in, binding and then change the molecule . The drug coes from the outside , in your blood say, and it has to go through the membrane. So it signals a change insid ethe cell, to understand that you need to see how it binds , and different states to the response. Then insid ethe cell there is a change. With the structural knowledge of the atoms , we look at the drugs , change a methyl group here or a sulphur or something and look to se ewhether it can still bind or provoke a different change. A Nobel prize fo rthis as nature has engineered this to be s flexible tha tthis is quite opposit eto what we want to do in CY, something that is always the same. Its elluded us a very long time, and now it is possible. ???, if you can get results in solution ??? ? CY is not a technique that stands on its own. If I take a result from a protein structure it doen't help me a great deal. As a scientist I would not be able to publish the data on their own. I can deposit this into a public depository on a database but this does not tell me the story. What I have to do is describe the reactions within the cell. You put things in solution and other techniques like spectroscopy greatly helping in understanding these results. And using ??? how molecules interact . Without that knowledge the structural work is kind of shakey. If you turn the molecule does the pattern change? Why do we get these spots on the film is the underlying question. The molecules are repeating inside the crystal. We look a tthe crystal in 3D ,get the difraction pattern and the diffraction pattern is in 3D , from this rotation. The difference that is appreciable and that we have to work with . From say an original Bragg picture. If you look carefully the degree of blackness of the dots varies and that is where the information sits. If you turn it , one gets more black and another gets less black. Can impurities in the crstal mislead you? Impurities are a great problem. We try to work as pure as possible. For a chemist you know you can recrystalise substances and that is a purification process. We take out only the things that fit into our crystal. Inside a crystal we think we have a pure substance, even if the original sample is not pure. Sometimes the molecules themselves have different conformations , they change and that is a problem. Some molecules can not be interpreted from the data . Conformational Heterogeneity , if you have 2 types of the same molecule in a crystal then it doesn't work. Some of those early iconic images . I thought Rosalind Franklyn was the uncredited person behing the DNA Xray images but you mentioned a Dorothy Hodgkins in that role. What is the connection there? No it was Rosalind Franklyn, i meant, in that role With the new very high power free-electron laser generators and images in a couple of femptoseconds , can you do it while in solution , without crystalising? I appreciate you would have no choice about the orientation, but could catch it before it had moved. ? The dream of the original proposal is that you could see a single molecule , that was exactly what they proposed , to observe single molecules in solution. Technically not possible, why they use crstals. These crystals are pretty small . Calculations now show a limit of 5x5x5 molecules is sufficient for a crystal So how do you define a crystal? A crystal is a lattice which has a repeating unit . Is there a minimum number that you can still say it is a crystal? I suppose 4 repeats in X,Y and Z then you could call it a crystal, 2 is too few.

Monday, 08 July, 2013, Gary Morse, of the Russell Society - Geological Time: The discovery of geological time, how it is divided up and how the times are worked out. 3/4hr talk, 3/4 hr Q&A, 29 people. I.m not a geologist, I'm a chemist by profession with a long standing interest in mineralogy. To understand minerals you have to understand minerals and rocks and theire place inthe great sequance of time and the history of our planet. I will talk about the deep history of our planet. We now know the age of the planet is about 4.5 billion years old. The best the USGS has for it now is 4.54 +/-0.05 billion years . Its hard to comprehent this huge abys of time. The standard model is the 24 hour clock , Earth was created at midnight , life appeared at about 6 o'clock in the morning , life came to the surface of the planet at about 10pm and we appeared at just after 1 minute to midnight. The talk is divided into 3, the age of Earth and how people tried to determine its age, the history of the earth and how they sequenced things , how they related what they were seeing to other events, and then how they put dates and years to those events, using radio-isotopes to date old rocks. The age of the Earth meant nothing to classical Greeks. A lot of religions like Hindu thought time and the Earth were eternal. To them a concept of a beginning was abnormal, it was always there. With the ascent of Judaism and belief in a god that created the Earth that people started to think about a point zero when creation started/ . This started the great minds of the time to work out whan was that. Many people had a gp. There was Theophious of Antioch in AD169. Isaac Newton also made a serious attempt, going back through the masonic records going back to ? ante-diluvian , through middle eastern literature and the bible. The bible is a chronography , people are named by generation and could work back to Adam and the creation. They all came up with a remarkably similar age. Archbishop Usher of the Church of Ireland at Armagh, he calculated it was created in 4004 BC. The date became so popular , a number they could work with, it was included in the marginalia of the King James bible. He stated that creation was the nightfall preceeding Sunday 23rd of October , 4004 BC, of the Julian callender , precisely. Good science of its time, using records and calculation . Now considered bad science. Just today on the news evolution is back into school curriculum for 2014. But the creationists still believe in 4004BC. Along comes the reformation, the renaissance, the birth of modern science and the scientists now start to get involved. The Compte de Buffon , George Lewis de Clerk? , he thought that the Earth cooled from a hot molten mass . He heated up iron balls , different sizes some huge, allowing to cool slowly , calculated scaling to the Earth size and he determined the Earth took about 75,000 years to cool. Good science but based on some bad assumptions, the main one being that the Earth does not generate its own heat. Helmholtz , he thought about the Sun condensing from a gas nebula, he got a figure of 20 million years. Along comes William Thompson, Lord Kelvin , he knew of temperature gradients , starting with a starting temperature of 7000 deg Fahrenheit , knowing the geothermal gradient was about 1 deg F per 70 feet in depth. As you go further into the Earth it gets hotter and hotter. The gradient had been measured in mines . Again he got a cooling age of about 20 million years which tied up with Helmholtz , 2 different approaches, 2 different methods giving the same answer and people were comorted by this at the time. But again the assumption had been made that all the heat that is in the Earth was heat from the creation. No knowledge of radiation and radio=active decay generating heat, and heat was still moving out from the planet. Again good science for its time. Geologists got involved . Charles Lisle a great geologist of his time thought the key to aging the Earth was the rate at which sediments formed. He said errosion was constant , so is sedimentation constant . So if you knew the rate of errosion, then rate of sedimentation he could calculate back knowing the depths of sedimentary rocks and get a date. Difficult as rates of sedimentation vary from a few mm per year of ocean beds to metres per hour in river beds in flash flood situations. He was going back 100s of millions of years, pushing this earth-age back , further and further. Then we come to Darwin and evolution. He required evolution to take place through small incremental changes over a very long time. The time to go from primitive single cell lifeforms to the complex was much more than the 20 million years or so of Kelvin etc. Kelvin was a staunch opponent of Darwin's theories on evolution. He said there simply was not enough time . From Alfred Wallace , "Kelvin's views on the recent age of the world have been one of my soreist troubles". He had doublts as well as if Kelvin was right and 20 m he could not see evolution bringing us to where we are today. Very controvertial in the 19C and the arguments raged on. John Jolie a physicist, he used Edmund Halley of Hally's Comet and his thoughts on the salinity of the oceans. If he knew how much salt was going into the oceans , carried in from rivers that he measured and determined . If the salt continued to accumulate in the seas , work backwards to no salt in the sea and he got 80 to 150 m years . Again good science , poor assumptions, assuming salt remained constant but now known that geological processes and submarine events that remove salt , sometimes rapidly, so a steady state situation, an equilibrium. If Jolie had known about that , he would have got a longer age. So all estimates based on assumptions, they did not no about radio-activity and internal heat generation in the Earth. They were pushing in the right direction. We now move on to geology and Danish priest Nicholas Stanhoe , 1638 to 1686 who came up with the 3 main principles of geology still applied today. He understood how the planet was evolving and moving , sediments build up from the sea floor , laterally , horizontally and continuously over large areas. Sediments at the bottom will be the oldest, much as the pages of a book , you can read from front to back you can read earth history from botom to top through the beds of sedimentation. This is the Principle of Horizontality, Principle of lateral continuity and the Principle of superposition, younger layers are on the top of older layers. Abraham Verner ? he proposed that all rocks had een deposited i na wold-wide ocean, Noah's Flood ,religion still rife. Every single rock on the planet had been formed in an ocean, even granite. He divided the geological record into 4 main divisions. Primary, Secondary, Tertiary and Quarternery . We still keep the Tertiary and Quarternery in our geological series. His theory of all rocks being deposited i nseas is called Neptunism. This did not explain the gaps, people noticing gaps in the strata. Strata had been moved and new rocks laid on top. Many places around the country where continuous horizontal layers of rocks were discontinuous, there were gaps. The person who thought these through was Hutton. From his colleague John Playfair commenting on seeing this unconformity at Siccar Point, Berwickshire"the mind seemed to grow giddy by looking so far back into the abys of time" We have here older Silerian greywackye deposits, sedimentary rocks, they/ve been uplifted and folded from the horizontal, formed horizontal, and forced upward by tectonic forces/ earth forces and they are vertical. On top of these are old Devonian red sandstones Siccar Point is a Mecca for geologists. Hutton called these unconformities, he knew there were gaps in processes of time. There are pages missing from the books , but you can find the pages elsewhere. This is where we go to maps. Hutton is credited with creating uniformitarianism, a fundamental principle of geology. It explains the features of the Earth, the crust and the rocks by natural processes in geological time. Given enough time, things will happen, you will erode mountains and build up huge layers of sediment. He;s often called the father of modern geology. So we started mapping these rocks. And it is William (Strata) Smith , a hero of mine, he worked at Bath and the Somerset coalfields. While he was down Meons Pits , as a surveyor and engineer i nthe coal mine that he noticed rocks that he'd seen carrying similar fossils he'd seen in work being done on the Somerset Coal Canal, also a surveyor on there. He started putting 2 and 2 together and they must be the same rock, but at different levels below the ground. He could then start mapping. He lost his job , he died a pauper , spent time in deptors prison . Read Simon Winchester's book it is a sad tsale, he was robbed of all of his works, which were plaguerised , he lost his intellectual rights to his maps. You can download his map off the internet in pdf sections and you can piece together to make your own full size map of strasis ? . It is amazingly accurate, even comparying to modern day geological maps of the UK. It has the Liass going from the South Coast up to the north Yorkshire coast , the limestones of the Mendips , the chalk downlands, the Cambrian rocks , the Silurian rocks . We did not have names for these rocks . Smith did not give them names , nor sequences . Just saying , I've been there, I know what rocks are there , and drew and extrapolated, via the fossils, from one area to another. His fossil collection was quite extensive, some believed to be in the Rotunda at Scarborough where he spent the last of his days . He had helped to build the rotunda. Although he used the fossiles to identify the strata, he did not understand where they came from. Fossils were always thought to be there from Noah's Flood , the creation , not realising they were extinct animals. It took Puvier? and Lisle to show that fossils were the remains of extinct animals. Puviere studied the remains of modern elephants and mamoths and he concluded that mammoths were extinct versions of elephants. A huge shock to modern society, because they still had the notioon that god created all around us and why should things be allowed to become extinct. What we have on the planet has always been there, nothing ever different. Lisle did work in the French Tertiary deposits, and found that as he went down through the strata , that the fossils in the lower beds , the Eocene beds , more of those were extinct than in upper Pliosene levels. The upper fossils he could equatre to modern day living animals and shells. Going deeper , more and more could not be recognised in modern creatures. There was a succession of life as well, fossils and evolution. Lisle split these tertiary rocks into 3 areas , oldest to youngest, eoilisene from eos meaning dawn , the miocene the less recent and the pliocene the more recent. We still use those terms now. The race was on , stratigraphy was born. And everyone wanted to get there terminolgioes in there for naming a bit of the geological timescale, the successions of rocks. What they are looking for is boundaries in the rocks , where 1 fossil completely disappears , one rock type changes to another rock type , different banding or structure. There was no bigger war than between Sedgewick and Merkeson. Sedgewick , geologist, museum at Cambridge named after him, his collection is in there. Merkison was the first head of the British Geological Survey, Merkeson House is in Edinburgh. They never spoke to each othe r for years because of this war. Sedgewick mapped the rocks in Wales, some of the oldest rocks in the country, containing the oldest known lifeforms in the form of fossils. Sedgewick wanted to cal it all Cambrian , the latin for Wales but Merchentson proposed the Silurian after Silurs an old Celtic tribe. the 2 were continuously at loggerheads. There was not much difference between the 2 ages , the differentiation between the 2 strata, to split them into 2. Along came Blackworth , he found a middle bed that split the 2. The oldest was Cambrian, in between he put the Ordavisian from Ordavicis another Celtic tribe, then above that the Silurian. Cambrian going back to a time when there was very little primitive life and no life at all. We have relative aging here, we know one band is older than another, the science of stratigraphy. We move to geological periods of time, carboniferous after the carbon coal bearing rocks of Yorkshire, Cambrian, Ordavician , Silurian, Devonian from the red sandstones in Devon, the Quaternary and Tertiary have all been split into other groups now. The Tertiary is now down to paleocene . Triassic comes from the Trias area, Permean from Perm on the outer edges of the Urals, Jura for Jurassic . The largest divisions are called eons , divided into eras periods and epochs . So Lisles oldest rocks the Eocene in middle France belong to the Eocene epoch, the paleogene period of ?zoic era of the phanerozoic eon. We still have no dates for any of them . We cannot say how old they are. Continuially being updated by the International Commission on Stratigraphy, of today the last update with them was Jan 2013. Continually changing the dates and events . We kow something happened between the Cretaceous and the Paleocene. A mass extinction of life , beleived to be from a meteor impact in the Yucatan peninsular, wiping out 90% of the life on the planet, not just the dinosaurs. What used to be called the K-T boundary , we don't use the word Tertiary any more, now called paleocene there was high levels of Iridium identified at this same timepoint around the planet. Iridium is found in meteors, but when was this. This is where radio-metric dating comes in. Henri Bequerel discovered radio-activity providing the way for precise dating. Depends on radioactive decay . Start with a parent isotope like Uranium238 , will decay to a daughter isotope Lead206 giving off an alpha particle, alpha decay , loosing particles, loosing mass, changing from one element to another. The rate of change is the half-life , the time taken for an element for half the atoms to change from the parent isotope to change to the daughter isotope. Leading to an exponential decay curve on a graph plot. We can weork out , if you know the half life , and count the ratio, you can then backtrack from the graph to find when it was 100% parent isotope. Determining the half-lives is fundamental. Because the curve is exponential it just continues decaying and decaying . We have various long half-life elements, from Potassium 40 to Argon 40 , 1250 million years. Samarium to Neodimium 1060 million years, Uranium isotopes to Lead 704 million /4500 million. The Carbon14 decay is only 5300 years , no good for geological time , by a few thousand half lives its all gone , not enough to detect. C14 is used ffor archaeological dating of bones, seeds and wood and charcoal. Like an hourglass of U235 and U238 and run them , they run down at different rates , so by looking at the ratios we can calculate . The pioneers were Rutherford and Holmes and yusing U235/U238/Lead daughter products assuming the parent was 100% . Holmes dated rocks in Ceylon back to 1600 million years, suddenly pushing geological time , way back, when others were saying the Earth age was just a few million years old - a revelation. His work could not be faulted . So the race was on to find older rock. The oldest suite of rocks on the planet are now determined to be the Acasta Gneiss in northern Canada near Alaska. The Gneiss are metamorphosed rocks , old sediments that have been put under pressure , contorted and recrystalise out . So contain rocks that have been eroded and recycled. They contain Zircons , grains that are extrememly durable , recycled, don't wear. They come down rivers in sediments, deposited in the oceans , turned into rock , heat and pressure contorted and driven up into mountain systems again and the crystals still remain. Find those and you can date the rocks. The Acasta Gneisses are dated at just over 4000 million years old, nearly back to the age of the Earth of 4.5 billion years. There is a company selling samples of this rock, they claim to have the sole rights , a licence to take so much rock and sell it every year. Selling it for phenominal prices. Its been around a lot longer than we have so ownership? The oldest rocks, found in Australia , again recycled zircon grains , when they date the radioctive ratios in those , it comes out at 4.4 billion years old. For U235 and U238 if say 2 half lives for one and 8 half lives fo rthe other , from that ratio of the 2 clocks , you can work backwards. From coalescing from the dust and particulates floating around in the early solar system. Zircons are a lot more valuable than we give them credit. Tough , durable, same refractiv eindex as diamond, almost the same hardness. We have stuff from outer space, that has arrived on the planet as meteorites, this is the Kenyan Diabolo? meteorite , we can use those to date the Solar system , and 4.5 billion years. The human has been around for about 2 million years but it has had such an impact on the planet that they are now proposing that the new geological age should be called the anthropocene, the age of men. We've had more impact , in our short 2million years than any other lifeforms Q&A Ratiometric data ...?,,, started as pure uranium235 say.? We know from the isotopes, what we get the atomic weights from. Carbon is not 12 exactly because its C12 and C14 . We know isotopic ratios when they form in the Earth's crust. There are hundreds of isotopes of some things, some are stable, some are not. Also on that topic, I'm aware that in archaeological terms , for radio-carbon dating that they can only sensibly use between 10 times the half life and 1/10 of a half-life , 50,000 years to 500 years, for any statistical significance. But going the other way foir an isotope with a half-life up in the millions of years how do they determine that in the lab with any reasonable statistical reliability? That worries me as well. If you have to wait 4.5 million years for U238 to decay to as half , how do you know that. This is where the estimates are coming in , they are always redefining and refining these times. Its not like radon and measure over 3 days and count the numbers of atoms decayed. But when you see the half-lives quoted to 3 or 4 figures it suggests to me that there is a very precise mechanism behind there somewhere . With the archaelogists with all the academic clout behind them, are restricted to the 10 to 1/10th range, I just don't see how it can be scaled up by a factor of 1000 with any precision? You can look at the decay rate in as much as the rate of evolution of neutrons or the evolution of helium nuclei , the alpha particles. You can say how many are decaying in that period of time , there are ways of doing it , with the new mass spectrometers, finding individual single atoms. I think now they cam almost watch single atoms decay. I do wonder if it becomes temperature sensitive over time or other variables that come in ? That is the thing. We are assuming the decay rates have never changed and do they change. They are proposing that protons have half-lives but we have not been around long enough for a proton to reach its half-life. Somewhere along the line between Bishop Usher and Lord Rutherford , was there anyone who predicted the age of the Earth to be in the billions of years? No. Quite a dramatic change, wasn't it? It was a large culture shock. Always underlying it was the religious thing. If something went in conflict with your findings or theories , well that is the will of god, they went off and did something else, they didn't question why. Just god set it that way, god creates the world and makes it the way it is. Always there was the fear of upsetting the church. The church loved Bishop Usher because he used the Bible. Anyone else tryoing to push it back further, and all they had to say yheere has not been enough people to fill the Bible, not enough begatings. Or they had to live a lot longer than we thought they did. To understand what has happened to this planet I do believe you have to have an understanding of how it has evolved and its deep history , what has changed. Because we can't look to the present without knowing what has happened geologically i nthe past. It is continuous. I work with stone, so I understand quite a lot about the stratas and the like. Most of us ingest things that are around us as part of our diet. There is a lot of work going on with DNA , migration and identification of people's migration patterns through time around the world. The age of the rocks in Australia and age of the rocks in Canada. There is a theory that man evolved in one place and spread to different areas of the world. Is it worth questioning, going back through the DNA record for all the people of those areas to determine whether they evolved at different times? You cannot go back to organic remains , which is the problem. Geological time relies on things that are unchanged over millions of years. Rocks are not created or made, they are just changed. The calcium of living organisms has come from somewhere else and you can work out . They are taking the calcium of shells under antarctic lakes , drilling down through the ice, pristine, unexposed to atmospheric CO2 for thousands of years and looking at the C ratios in there and they can say what the C ratios were in the atmosphere then, as not adulterated. When life stops the C ratios are fixed. While you are alive you are taking in C and giving out C ,the ratios are being adjusted continually. When you die , that stops, C14 continues to decay , how much C14 left in you tels them how old you are. They are doing the same with Lead now. Remains on Salisbury Plain , lead i nthe bones , from the ratios can say where they were living predominately. The lead-ratios there may correspond to the Mendips . For N Yorkshire , would be coming from the lead in that area with different isotope ratios. Across the world you could possibly track back isotope tatios in bones and teeth , the things that are preserved and relate those to the ratios found in different areas. The Russel Society as amateur minerologists and geologists have been asked to supply small samples of Galena , a common lead ore, found extensively around the country. In limestone deposits, a low temperature ore deposit. Exactly where and when it was found , send it of to the BGEST ? , they work out the lead isotope ratios and they can relate that back to the local population. So whether the people in those areas of Canada or Australia had evolved there or they had travelled there? The rocks in Canada were not up near the Arctic when they were formed . They've been around for 4.5 billion years, part of a super-land mass, split apart , migrated from one side of the planet to the othe rwith tectonic activity and continental drift. Mankind almost certainly evolved in th eGreat Rift valley of africa. For ages the Chinese tried to prove that their original men came from China, but the DNA record showed very clearly that they too came from Africa The detection systems are moving forwards rapidly, they can detect individual isotopes by a few atoms, the time of flight mass spectrometers. They are roaming around Mars now, measuring the isotope ratios on Mars and finding they are different to Earth. But the ratios are similar to the meteorites found on Earth Can ratios of 3 or more isotopes be used? The more you get, the better, Potassium is one that works quite well because it decays down to Argon . All the Argon in our atmosphere is derrived from Potassium decay. It is potassium decay that is driving the energy within the Earth. A mass of radioactive potassium in the Earth that is heating up the Earth, confounding the LeClerk, Buffon cooling of iron balls age-determination. There is a mine on the N Yorkshire coast , Balby , they take out potash for Miracle-Grow, also a lot of kaolite, salt. The Havensite? in the rock . To find the highest ore content they drill in witrh a boring machine , working at temperatures of 50 to 55 degress down there a 1.5 km down there. They use a Geiger counter on the front of the boring maschine and from the highest readings they can say it is the purest ore, to target . The same beds carry across the country , to Cheshire , it is all salt . The valuable stuff is not there, it is only at N Yorks. They are now talking of drilling under the N York moors to win this mineral, again to exploit these potash beds. It has a long half-life . I can look up the number of ratios. Potassium - 3 isotopes, potassium 39 stable 93%,40 is 0.0117% of all potassium and 41. With the naming of geological periods , epochs or whatever the term is, it seems very Eurocentric , from the Jura , Devon etc . Has South Africa got its oar in or others? The Americans have taken to reclassifying things like Mississipian and I think we've lost the German West Phalian has been split up. Americans tend to use different terms for the same period. Unfortunately the Inernational Commission on Stratigraphy is in America, with a lot more Americans and Canadians than Europeans sitting on it. Life appeared at 6 o'clock in the morning of the Earth "clock" , is that the mono-cellular life or is that earlier. Mono-cellular life, the simplest forms that can reproduce themselves. Its possibly been pushed a bit further back. I've heard 500 million years.? Bacteria and things like that, identifiable organic life-forms , capable of breeding and interacting with their surroundings. We will never know for sure as these things are so poorly preserved . What the origin was is still speculation. I do wonder about the science sometimes when they find a piece of bone just mm long . A quarry in Chichester , they can firstly identify it as part of a shin bone and then draw a complete man out of it complete with facial features, Boxgrove Man. And on the Isle of Wight every new piece of bone is a new dinosaur. As the newest piece of bone does not look exactly like all the previous but if you take human bone , dig up a few human femurs from a cemetary, lain side by side, they will all be slightly different shapes but they are not different species. Just different forms of the same thing. The other one that worries me in the fossil record is where are the babies. A small amonite is just a baby one of the adults, its not a new species, where is the sequence of growth. Things don't appear that big, there must have been little ones. As there was predation, there must have been many more little ones until we get to the big ones. The K-T boundary layer, I assume it is thickest around meso-Americas. How thin is it still observable around the world , far from there.? They found it in a place in Denmark called something like Stephan's Clint , the discontinuity had been known to be there a long time. It is a beach exposure . It was samples from there that were first identified and poo-pooed out . The first explanation was that it was due to the woman grinding the samples was wearing a wedding ring and contaminated with iridium. Then they looked at the K-T around the world and they found much higher levels. What is the thinest that anyone has managed to find? Can you see it by unaided eye? No , there is no discernable layer that you can say is meteoric dust . Its within the sediment that has fallen that created the rock. Taking samples in a vertical line , the quantiity of iridium increases and then decreases. The iridium has not leached down or worm activity? Iridium is amazingly insoluble , it will stay where placed, that is the beauty of it. The isotopic ratios are matched to certain types of asteroids . Is the K-T boundary exposed in this country? I think those rocks tend to have disappeared in this country. We miss out that junction, to the Tertiary. I'm not too sure on that. Its still called the K-T from the german cretacious K but we don't use the tertiary term now, the paliocene. When was the K-T dicovered? About the 1960s Dartmoor and Radon gas. I understand that volcanic activity created the granite could you tell me about that process? Thorium in those rocks gives rise to radon. From the granite of Dartmoor and other areas, radon is a problem. When the granite was emplaced, there was a lot of radioactive minerals in there. Uranium was one, Dartmoor has a lot of uranium minerals. Radon, thorium , pitchblende and the like down there. Monozite as thorium oxide . Therer was radon build up in the mines . Radon is a gas with a half life of about 3 days , quite a dense gas , a noble gas that does not react with anything . So you breathe it in , it decays, but it decays into plutonium. That is a solid that stays within your # lungs and then lung cancer. It will always sink to the bottom part of the house and so you put a sump in there and a fan. And periodically you have a man come round to do a radon survey. Its not just a scare story then? No its very real. Going down old mines in Cornwall they will always check for radon. I used to live in an old stone cottage on Dartmoor and was involved in dry stone wall building? It was Kilas ? the shales and bedded slates used for walling because they cleaved easily. Granite was used for commercial applications. Merivale, the big hole on Dartmoor where a lot of ornamental granite came out of , some beautiful uranium minerals came out of there, yellow alternites? very highly radioctive. The problem these days , with old houses, they put in double glazing and block up chimneys and no through ventilation. The stones for dry stone walling came from rocks laying around, so no radon from those . There is a lot of radioactive piles in Cornwall . Go to West Wealales? by St Juste on the SW coast , all National Trust now . You can sit on these lovely grassy tussocks and have a picnic. But those tussocks are mine waste dumps that have grown over but are full of pitchblende, a Geiger counter goes off the scale and people are sitting there having a picnic. What about water travelling through the rock , will that carry radon? It will take up a small amout yes. We have to be exposed to some of these things , its part of ape evolution. The amounts are so miniscule that they won't do you any harm. You are probably exposed to more radiation in an airdcraft flight from UK to USA than sitting on a tor in Cornwall for 6 months. Courtesy of one of the talks in the earlier incarnation of these science cafes , in the Soul Cellar. A speaker from believed UCL, the technical term is Hormesis which I'd never come across before or since. The concept that a little bit of what does you harm, does you good. He was a government advisor on radiation policy, involved in thePolonium Litvinenko poisoning etc. TheWHO guidelines for radiation is - No Radiation, there is no such thing as safe radiation but there are acceptable limits. New York Central rail station has highly radioactive granite in its construction, but it won't be pulled down because no one spends enough time in there to be unhealthy. Do you believe that crystals emanate energy? No Do you have a good collection? I do, takes over the house/ Could you explain what the Russel Society is? It was born 40 years ago last year, in Leicestershire as the result of an evening class run by a prof Bob King, a lecturer on mineralogy. They started a minerology society that grew to a large membership . Its aoms are to study , preserve, curate and understand geology and mineralogy of the UK, both amateurs and professionals . Its now grown that we have 7 branches membership down from 700 to about 400 which we are aiming to remain stable at. I'm chairman of the southern branch. We hold talks in the winter months , huge range of field trips , around the UK in the summer around mines , quarries and geological sites. We also do a lot of work with museums and people with old collections. Noteably the Chatsworth collection, a collection made by George Yarner? , the largest Colombian emerald ever identified , Colesburg ? silvers native silvers . Our past president Roy Starkey has just been to Braemar House and uncovered a large collection of agates and Scottish minerals. Carhayes ? House in Cornwall , th eWiliams collection early 17C who sold minerals from their mines in Cornwall. Bournemouth natual science society asked us to look at their collection as they did not have a mineralogist in their membership. Large Platinum nuggets in that collection, they did not know they had. You made it sound as though Zircons were mor evaluable than diamonds.? Zircons are because they have been around a lot longer. I thought they were the bane of diamond dealers lives as they were difficult to distinguish. You can't date the planet from a diamond. Its pure carbon. The generation process for a diamond just needs a volcano, not necessarily very old? Yes at very high pressure If I go to a cliff and see 5 layers will it aleways be 5 layers or will there be other periodicities? Yhere are seasonal changes , called Varve ? layers , thin /thick due to seasonal changes. Summer deposistion rates are lower and evaporation rates higher so more salts , more evaporite? minerals. These will weather at different rates so banding. Some may have more iron in , and more oxidised and different colours. In the winter with more material piled in due to more rainfall so seasonal differences can be worked out. They can see flash floods , uneven layers called turbidites where there has been turbidity. Periods of dessication when nothing is happening. Varve layers are usually found inlakes . You can see them in the clay layers of the Mendips quarries, oolitics, in the clays between the utrites?, different coloured bands . I have trays of little calcite crystals , sieved out of the muds. During summer and shallow lakes, evaporitive deposits , the salt levels have risen to the point of crystalising out. Like the scale inside your kettle, it is formed inside the clays, then another layer forms ove rthe top and then the same thing happens again. Take the thin layers and wash them through . In some areas the calcites can be 2 or 3 cm long, beautiful, perfectly formed without a mark on them, without any hindrance on their growth within the sediments. If you had a bit of tree in one of those layers, carbon date the bit of tree , you can then see the year distinctions and give dates for the layers. Very fine layers, you wouldn't giove eacj layer a name though. Its major changes of species in the fossil record to another species or a major change i nthe rock type , leading to the naming of layers, layers a good few feet thick, thousands of years. We don't go down to hundreds of years as our scalings are only quoted to plus or minus 1000 years. The radioactive dating is good but not that good. The 1% error of 4.5 billion years is still big. Its not Bishop Usher's 23 March 4004 BC, we'll never get to that accuracy. They must have come across contradictions within the bible, how did they deal wwith that? Within the bible and contradiction with other records. He used the masonic registers, the antediluvian records, suposedly more cronological accounts. What stonemasonry records is built up on. Masons is a sect , with a written history, throughout Europe and the middle east , going right back into time, apparently. Theosyphilus of Antioch used the bible and scriptures only. They all came out abou the same, some ages of kings difeered but balanced out in the sum . All about 4000 BC, which you will do if working from the same data. I happpen to know a few master masons , do their records , of the types of stone used etc,go back beyond this eon? Back to Nebukadnezar or someone like that . I'm not a mason, I don't know. There are these chronological records in libraries and institutons about the world. Those records then cros-tie with events refered to in the bible like the Exodus, Israelites coming out of Egypt. Those stonemasonry records go back before the time of Christ. The AnteDiluvian records, going back before Noah's Flood. THe biggest loss was probably the library in Alexandria.

Third monday of the month, 19 Aug, 2013, The aging process with emphasis on the aging of the brain and the eyes. Two person presentation by Salome Murinello and Ben Malcahy of Southampton University, Medical Sciences 1 1/2 hours, 46 people Ben Mulcahy Why do we age. As we age we change quite a lot. Going from baby to adult we go through developement , a san adult we are in our prime . As we get older we get grey hair, wrinkles , start to have impairment in oour memory and our learning ability. As we get even older we get frail and become vulnerable to diseases such as Alzeimer's etc. There isn't a definition of aging. People have looked at aging from a philosophical point of view for thousands of years and fo r a scientific view , for hndreds of years and we still don't actually know what happens. The best definition so far is that over time there is a decline in the function of our body systems. We call it dirrerently from disease. We get wrinkles because the collagen in our skin starts to break down. We get things like bad memory and weak bones. Whilst grey hair and wrinkles are acceptable , you can get along with them, when your memory goes and your bones start to become weak , its not optimal. And an increased general vulnerability to disease. The best answer as to why we age is from an evolutionary perspective. The only point to us having these bodies is for us to replicate our DNA and pass it on to a next generation. So basically we live to reproduce - that's the meaning of life. After generating the next generation, most organisms are biologically useless, there is then no meaning to life. Thankfully for humans we have a rearing period where there is parenthood and a continuing use for grandparents. An introduction to evolution. It works by natural selection. For thousands of years mutations build up in our systems and they result in different phenotypes . If you're a mouse and you're living in a forest and let say at one stage mice were bright pink it would be picked off by predators very easily, against the green of the forest. If a mutation arose that led to it being grey it would be much harder to see the mouse, an advantageous mutation. It increases the number of progeny that can be created and increases the liklihood of progeny to survive long enough to create their own progeny. So a numbers game. So why don't we last for ever and reproduce for ever also. As we evolved most of our evolutionary history has been in the wild where there are limited resources. We only have a certain amount of energy that we can distribute to our different processes, eg growth, mainainence , repair and reproduction. The priority is to get to reproductive age as fast as you can and reproduce as much as you can before there is a high likelihood of you dying. Initially it depends entirely on environmental circumstances. I've introduced extrinsic mortality and intrinsic mortality. Mortality is just dying , extrinsic is dying from external circumstances such as predation or disease and intrinsic is from internal circumstances eg aging or age-related disease. Throughout evolutionary history, the extrinsic mortality has controlled the timing of the intrinsic mortality. An example of a mouse in the wild. About 90% of them die within their first year although their lifespan is about 3 years. Mainly due to predation or disease. Evolution favours the majority of mice that manage to reproduce before 1 year and it doesn't matter what happens to the mice after that phase as they are not likely to be alive anyway. The soma or body of the mouse is disposable , it exists purely to reproduce and replicate DNA , before they die. The disposable theory of aging. Under this theory there are 2 partly complementary , partly competing theories, how aging happens, in a very broad mechanistic sense, Antigonistic ?trophy that mutations that give advantage in their early part of the lifespan are selected for by evolution even if they result in a disadvantageous phenotype later in life. An example of this is a gene involver in Alzheimer's disease . The other is mutation accumulation where theoughout evolutionary history , random mutations have built up in our genome and because they only result in disadvantageious pheonotypes later on in life , they haven't been selected out by natural selection. As always in biology, there are exceptions to the laws. A jellyfish species that is immortal organism , an adult stage reproduces or injured it goes through a series of stages back to its larval form and completely rejuvenates. Obviously if it is eaten be a predatior it wouldn't be immortal. Aging leads to a decline in function. Its because of the environment we are exposed to through developement. And the major pillar of aging is that the germ-line or DNA that matters and not our body. Different organisms age at different rates. C-elegans the 1mm long worms live 2 to 3 weeks. Drusophilar , fruit fly, 4 weeks, mouse 3 years , chimp 30 years, humans 100 and there are trees that live to 80,000 years, the oldest known organism. What is the difference in these species, its genetics. There may be a genetic component to aging. Some people age better than others. People of the same age, say 80 could be healthy or not healthy at all. We can take advantage of this and look the genome of the healthy and the unhealthy old people. And pull out differences that may give us an insight into what makes some age better than others. There are 4 genes that have been reliably implicatesd in this. One set of genes is involved in the insulin pathway , but difficult to see what role this has in aging, its involved in metabolism. HAPPA-E ? protein that is involved in Alzeimers and its involved in clearance of ?s from the brain and helps keep the brain healthy. A gene involved in fat metabolism and another gene that is involved in telomeres. We don't understand how it works. In the 1990s someone did a review of all the literature and he found over 300 theories of aging. A theory , at least in popular culture, is oxydative stress theory, you have all these supplements that are anti-oxident , anti-wrinkle creams etc. Evidence suggests that oxidative stress doesn't actually cause normal aging. If you expose organisms to high levels of oxidative stress it will be bad for them but if you then expose them to acid , then that too is bad for them but it does not mean that acid causes aging. The evidence so far is that oxidative stress is not the cause of aging. Telomeres - part of the chromosomes, generally held together tightly by proteins in the X shape and at the ends of the arms there are the telomeres . As our DNA divides and replicates , it can't copy all the way to the ends of the chromosome arms , so on each replication you lose a tiny bit each time. The telomeres is DNA that is not used for encoding proteins or anything , just there to act as a buffer and they get eroded with time. Recently this theory of aging has gained a lot of popularity, ? drift that is closely linked with antagonistic theory of aging. Pathways that are involved ion the developement of organisms , go awry later on in aging after they've passed their reproductive stage. Biology is a mess , in comparison to a car say. One component connects to another, and simple functions. Differnet proteins working to different pathways , they all speak to each other and they speak to other proteins and back again. So a massive web of complexity so its possible that a lot of different things contribute to aging , to different degrees at differnet times. There is also chance events and the theory of developement pathways go via aging. How to age slower. A recent one is dietary restriction where you eat very little food , using mice and litter-mates , one a small amount of food and one can eat whatever it wants, and a much shorter lifespan and much less healthy in old age. The same for monkeys. It is still not certain that dietary restriction affects aging. I'd rather die quickly and have a happy life rather than eat a couple of carrots a day. We can eat healthily , which is not as bad as dietary restriction and exercise . Still not much fun . What if we can find the signalling pathways involved in dietary restriction. The signalling paths inside the cells that make us healthier and design drugs to act on those same pathways. A lot of money in this. There are 2 drugs that have come to the forefront one is rapamycin ? discovered on Easter Island acts on the pathway that senses the nutritional status of a cell and it extends lifespan in vertebrates and they are looking at it in mice. Metformin? which is a diabetic drug , acting on the insulin signalling pathway. Shown to extend lifespan and healthspan in vertebrates and mice. So interesting to see over the next couple of years to see how this goes in humans. What I work on in Southampton is the aging brain. As we age , our memories get worse , we are not good at learning new things. Our motor control becomes impaired . Not everything declines with age, our knowledge of a subject , say science, we seem to retain that quite well. We also get an increase ? to disease . Initially wiht the aging brain , the nerve cells might die, but this is not the case during normal aging. Unlike in Alzeimers , age related disease , you do get huge neurone loss. But they don't comunicate very well any more. A nerve cell receives and transmits signals to other nerve cells. They are not lioke continuous wires, lots of wires together but they are not in contact Threre are gaps between nerve cells where chemicals are released from the pre-synapse? and they act on receptors at the post-synapse and if enough receptors are activated , ions going into the cell, results in an electrical signal, basically a current. I'm interested in the aynapses and how they age. Synapse is derived from synaptin? which means to clasp in Greek as under high magnification they look like they are clasping. We get a decrease in the number of our synapses as we age and there is less communication points between the cells. They also work less well but it is difficult to know what is going on. Synaptic plasticity is where different bits of a synapse get increase or decrease in their strength. That forms a sort of code that can encode memories for example. It doesn't work so well in aged mice but we don't know what goes wrong with it. We use the very simple 1mm long nematode worm C-Elegens. Its nervous system works exactly the same as ours, same pathways. In the wild you find it in rotten fruit but in the lab we keep them on agar plates. The major advantage of C-elegens is its genetics and we can poke a flourescent gene into its nervous system and take images. The neuro-muscular junction, motor neve cord and the synapse between neuron and muscles. As they age they exhibit behavioral secline , they can't swim as well in a liquid . If we look at measures of synaptic strength , the strength of communication between different nerve cells , they increase during early age and then decrease. They increase in strength when there is a decrease in behaviour , suggesting that stronger synapses don't necessarily mean better behaviour. There maybe a co-ordination aspect there. In very aged C-Elegens , the synapses are acting at a strength similar to that of young ones, they are completely immobile. We have some ideas as to why that is. The language of the nerve cells, the electric signals that go through the synapse. The evidence so far suggests that C-elegens aging brain, is that communication at single synapses in very aged ones, is not so bad and seems to be an effect of the network and the co-ordination between all the different nerve cells that together act to regulate behaviours. Its possible that as we go from synapse to synapse we get some little erors that over time build up to create a large enough error to give behavioural impairment. More work onm this is required. Break Salome Murinello Recording failed , probably due to aging brain. A message from the talk is generally, that most damage to the eyes is due to ultra-violet , so wear UV blocking sunglasses. Q&A On the clear structures of the eye. ... an additional specific structure that renders it , rather than changing the cellular constituents ? The cloudy patches in your vitreous, most of us are born with it. Sometimes whan you press your eye you can see something floating . They are called floaters and your brain learns to ignore them. With aging you get more floaters. They are eventually not a problem , despite casting a shadow on your retina, the brain ignores them . Can you say a bit more about smoking and AMD, I don't smoke. ? A complicated question and I think different people will have different opinions. Personally I think the blood vessels that supply the retina are very important . The photo-receptors are very fussy cells , they need everything to be perfect. The blood vessels , behind the retina, that supply them with oxygen and nutrients they need to be in perfect condition. There is a lot of evidence that smoking changes your blood vessels , become more stiff and more inflamed and I think there is some connection there. I believe there is some damage to those blood vessels. I was hoping you would talk about the oxidents, you pointed a lot to oxidants and from my memory , smoking activates oxidant pathways , more than the inflammatory pathways? The oxidative stress theiry, there are a lot of supporters for it but I don't think it is that clear. One specialisation that you have on the macular is the blood vessels that you have in front of the retina , in all the rest of the retina, are not there. In that area the photo-receptors are solely dependent on the blood vessels behind the retina. It is also in that area that you usde consantly everyday to read etc. It is a very active area , it is always working , so there is a lot of oxidative stress , so it is possible that smoking tips the balance and the retina can no longer cope with. I think that if these questions were easy to answer then we'd have a cure for the disease. People who don't smoke can get AMD, people who take anti-oxidents can still progress to have AMD. Its probably a combination of these factors and then depending on some of your genes, some we know of and some we don't , some behaviour that you don't tell your doctor when they are taking these data, there are probably a lot of interacting effects. Would you say there was more prevalence now than say 150 years ago? These days we have easy communication with other labs , the data taken now is much more thorough than 100 years ago. So the answer is , yes, a lot more now and it is predicted to increase, because the population is aging more, so more AMD. In fact increasing by 50% by 2020. I was thinking about the war and the chemicals that we ingest in the way of preservatives etc? So is it changiong faster than the changing age demographic? I don't think so , its a difficult question. When your doctor is taking data on you , it is too easy to not be truthful. Degree of smoking, do you eat horse lasagna or beef lasagna? A lot of these things are hard to track back. Certainly a healthy lifestyle has been associated with better outcomes. Eating more fruit and veg , better outcomes for AMD. In evolutionary terms I can see that fast reaction times is useful to get away from a predator . But it seems that having synapses must slow down the transfer mechanisms, why are they there, what is their function? It happens surprisingly fast . For a given run, does that gap slow down the transfer of information? The gap is about 30nm , very small. There are 2 types, chemical synapses, that I showed, and the other are electrical synapses which are pores? between different cells where the electricity can pass straight through. The chemical synapses are fast enough for us to react and co-ordinate behaviours. There is a belief that if you take octeobite ? or vitamins in green vegetables , that will slow down the developement of AMD, true? There is evidence for it , again, people go to their doctor , fill in questionaires, I eat a lot of veg or I don't , and through that there is an association , oily fish as well. Every now and then there is a different hospital that publishes something that says our cohort of patients don't show improvement if they eat oily fish. With vitamins and antioxidants it is more or less established , the oily fish , omega3 , there is a lot of difference between different cohort studies. About 2 years ago they were doing stemcell research in Kings college , have you had any results from that? Doing quite well. They have successfully cured blindness on a mouse which is very promising. Its more than anyone else has managed to do with stemcells. The eye is the first place, even with an animal , to cure with stem cells. I think they just got approval to start studying how they could do that in humans. They still need to get stem cells from humans , to differentiate them . A stem cell is a sort of generic cell that can become anything. You have to program it to become a retinal cell. Because such cells are highly specialised it is very complicated . They've done it for a mouse but now they have to go through the whole process of first diferentiating the cells and when converted they don't go back to becoming something else, once they are placed in the eye. I know they have ethics approval, so they are moving on. So they have not done any research on humans at all? I'm not sure , to be fair, but I don't think so. They've done research with human samples , but whether they've moved to transplantation part of it, placing in humans , I don't think so. They would place directly in the eye? Yes . When they inject somethin into the eye , as the front pasrt is transparent, you can see where you are injecting it, as compared to in the brain say, where you cannot see it. They have made an chip that acts like photoreceptors and that they have implanted in humans - fantastic work. They have restorted vision to people who are completely blind. A tiny chip fitted at the back of the eye . They can see shape and form well enough , such as a door , which would make a massive difference for someone who can see nothing at all. What is the relation betwee naging of the brain and stimuli, like braintraining ? Some studies suggest that brain-training retains brain function with age . Some studies argue against it , so not clear. There is no harm in doing them. No evidence that it makes your brain worse. There is a chance of making your brain better. What are your results on nematodes? We have done exercise and that works. It was said that some diseases of old age is the result of genes and they were evolutionary selected because they confered ? at earlier age , do we have examples of such genes isolated , along with knowing the evolutionary advantage of them? Yes, in a vague sense. There is a gene called afolypoproteinE4? and there are different variants of this gene. You may have one variant and your neighbour another variant. There is an epsilon4 variant , if you have this and you start to age , your brain ages faster than people with other variants of this gene and you have a hugely increased chance of getting Alzeimers disease. Its the biggest risk factor that isn't age. It has advantages, people in Brazil with severe diarrhoea do better with AE4 allele but I don't know the mechanism of that. It helps them develop in unsanitary conditions as you would be in the wilds. Doing better meaning that they survive better. A higher chance to reproduce . I'm sure there must be other examples out there . Your netweorks that you talked about, I picture them like the tube in London, Circle Line , Central Line etc . There must be a controller somewhere for the underground, do you have a control centre in your networks? So Does it go wrong with aging? There is the network like the Tube, the main interchange stations , that have a higher input into the network than othe rneurons. Then the people say going into the network equating to sensory inputs. Some neurons are more important than others, the hubs. They help to maintain the network i na particular state . For nematodes , for forwards locomotion there is one particular neuron that wil lbe more active than one other neuron , a balance. When the balance switches , the worm goes backwards. The input to these neurons is sensory so if you tap them on the head the backwards one becomes more activated and it goes backwards. Does aging affect this? Har to tell. As they become aged, they become paralysed . THere are mechanisms being inferred, for example voltage imaging and calcium imaging, plenty of stuff to do. Isaac Newton famously grabbed a bodkin , I think is a blunt needle and placed it between the skull and his eye, what was he trying to do then? I've no idea. Is there any evidence tyhat different tissues in the body age at different rates? is there cross-body co-ordination of aging? even from an evolutionary sense. Certainly within the brain yes. Different areas age at different rates. Your brain is split up into different areas according to the tasks that they do, and those functions deteriorate faster in some areas. In terms of tissues, yes. One example is Sarcopenia? which is where your muscles start to degenerate , one oof the major causes of frailty. In recent years that has been shown to be more complicated because the nervous system , changes i nthe nervous sytem are responsible for the inititiation of that. Eyes can often go . Some parts of the body can be more sensitive to aging than others. Is the nervous system, in general, thought to be more sensitive to aging. ? I don't think its been researched enough. With patients with several conditions , they report changes in their sensory system, say with Alzheimers . The way they perceive things , the way they hear things , the way they see things. I think some of these more basic things have been ignored . A patient with Alzeimers has more pressing problems than not being able to hear properly. Its possible that your nervous system does start to degenerate at different rates . Do you know what is going on with brain aging whwere they remember exactly what they were doing as a kid but remembering of when they were 40 or 50 years old its just a murky mist? retrieving far back memories in preference to more recent? I'm not sure we completely understand it yet. Hazarding a guess that would be a plausible one. As we form memories in a certain region of our brain they are initially formed as short term memory and then they are moved into a different area of the brain, somehow, we don't know how. Its possible that the mechanisms responsible for generating short term memories and storing them , are differnt to storing memories that are further away in a differnt area of the brain. All very strange.

Monday, 09 Sep, 2013, Matthew Reynolds of the ISVR, Active Noise Cancellation - How to solve noise problems by adding more noise 31 people, 1.5 hours I'm a member of something called n-cubed , the idea is to get engineers and scientists communicating their work to the public. Some acoustical admin firstly. Some basic acoustic concepts. Passive noise control that has been around for years and the limitations of that and then the history and developement of active control. Then detail of one technique called Harmonic Feed Forward Control. Then some applications. Acoustics is about waves . Pressure fluctuations within air . They are tiny fluctuations. The atmospheric pressure at ground level is about 100,000 Pascals. A typical acoustic perterbation on top of that , say loud shouting achieving 94 dB that would be a pressure variation of around 1 Pa so 1/100000 of the ambient air pressure. The smallest noise that a healthy young person can hear is around 20 uPa. They are longitudinal waves back and forth , pressure waves of compression and rarification flowing through the air. There is another sort of wave, the transverse wave , go up and down like light. Some vibrations are transverse waves. Longitudinal waves are harf to draw so we tend to draw them as transverse waves, they behave in the same way, just different types of motion. In both cases it is tyhe energy that moves along. The particles themselves, don't, if you follow one particle just goes up and down, it stays in its own bit of space. Some ways of describing waves. The heigth of the wave, called the amplitude. Its frequency , the number of times it goes up and down in a second. 1 a second is a 1 Hertz wave. The lowest any human can hear is 20 Hz. We also use wavelength , the distance between 2 peaks and is the inverse of frequency. As the frequency increases, more up and downs in the 1 second and the gaps between get smaller and smaller. Also the term phase which isa fancy word for delay. Looking at 2 waves that peaks a small amount of time after the first one , its delayed , and the gap we call the phase. With these 3 terms we can describe any acoustic wave we want. The other concept is linearity. Generally, acoustic waves are linear , if you have waves of different frequencies they don't interfere with each other. So a high f wave going into something , a room , a tube, an amplifier or anything, it comes out the other side , its amplitude will change, its phase can change but it will remain at the same frequency. Add a lower f in , go in and come out the othe rend ,amplitude and phase changed but no effect on its f. Whether a f is there on its own or with another , makes no difference, each f is independent. That idea of linearity allows us to exploit something called superposistion. Because waves are linear, they just add together. Animation of small wave from left and big wave from right, when they meet they add together and drops down again. This is the key to active control, the idea of superposistion. When there is 2 waves and their peaks are together then they are in phase , where one is peaking and one is troughing they are in anti-phase, low pressure and high pressure, the net result is zero pressure. This is the key to active control, we call it destructive interference. If we can get 2 waves of the same f and same amplitude , but in antiphase, the resulting pressure is zero. A big if. Why do we need active control. What is so bad about noise. Noise is defined as any unwanted sound. If you have a garden party and you open a window and turn your stereo up, to you its music not noise but to a neighbour having a nap , its noise, he doesn't want to hear it. Noise is annoying but also has health implications. Excessive exposure can lead to hearing impairment, noise induced hgearing loss. A problem in many industries, people work 10 or 15 years in some industries , they come out and their hearing is damaged. Can also lead to stress, sleep disturbance , can affect learning in a classroom environment. Can reduce performance, say a pilot on an aircraft . It can also lead to hypertension and heart disease. The WHO estimate that 3% of excaemic heart disease deaths in Europe are due to long term exposure to noise. We want to control this noise. It suffers a decibel problem. We measure sound in decibels. We do that because human hearing is not linear , We measure things like weight or distance we use linear scales. So 20 Kg , double it and you get 40 Kg. On dB scalse, if you have a certain pressure , say 0.1 Pa of acoustic pressure and you double it , it goes up by 6 dB. If I shout really loud and manage to achieve 94 dB , the acoustic pressure will be 1 Pa, if I double that , it wil lgo up by 6 dB. So 94 to 100 dB . In the quieter situation I was adding .1 Pa of pressure in doubling , but in the louder situation I'm adding 1 Pa , 10 times as much pressure but the dB change is the same. dB scales are all relative to where you start. When doing noise control, we have a problem because the first 6dB we only have to halve the amount of acoustic energy. If you want to reduce by 12 dB you have to quarter the pressure, 18dB then an eighth. It gets progressively harder to make noises quieter. Its difficult to make loud things quiet. The dB scale semi-mirrors how humans hear. Humans have a ridiculous range of hearing from 0.0002 mPa up to 200 Pa a massive range and we hear in relative steps. A small change at a low level you will hear but a small change at a loud level, you will not hear the change. For traditional passive noise control. There are 2 ways. Isolation by putting a barrier between you and the sound or use absorption - you could add foam everywhere to reduce echos in a hall say. If there is a noise outside and you don't want it to come into the hall , you put a big heavy wall between you and the noise. For isolation , the heavier the barrier the better , the mass-law. Say a brick wall gives 10dB of reduction , if you double the mass of the wall you get 16dB reduction. It is also f dependent , low f sound , long wavelength and a high f short wavelength , when the low f sound sees a wall it looks quite thin compared to its wavelength and barely sees it and goes through. For a high f it is a thick partition so works better at high f. Its much the same with absorption, with fibreglass or foam i nthe space. You need thicker foam if you want more absorption and also works better at high f as nearer the wavelength dimensions. They are limited at low f and need a lot of materials , lots of mass which can be troublesome. So active control , acoustic cancellation. Comparing the 2, passive is purely dissipative, it takes energy out of the system, converts it to heat or reflects it away. Activ econtrol is additive , you are aadding more energy into the system , but in such a way as to reduce the overall nnoise level. It turns out that activ enoise control works best at low f so if you use both you get a broasd range of noise control. Active destructive noise control is not a new idea. When first thought of, the technology was not there to implement it. Recently it is in headphones, aircraft and cars. Paul Lueg , filed a patent in 1936 , for controlling noise in ducts. Place a microphonme, to measure the noise in a duct , pass the signal through a system , to a loudspeaker and at the loudspeaker produce the same sound but in antiphase. This is a feed-forward strategy , measuring the sound upstream and feeding it forward to your control and applying a control at that point. Active control sat in the doldrums for lack of the technology to accom[lish it. A few more people put out some more patents but not much else happened. In about 1956 William Conover published a paper , Fighting Noise with Noise. He was interested in controlling transformer noise , the buzz from electricity cycling at 50 or 60 Hz and the harmonics of that f. If he put a loudspeaker in front of the transformer and he connected it to a harmonic source of the same f he could play with the amplitude and pahase of the control sound from the speaker , monitor with a microphone with its signal passed through a sound analyser and adjust the control until the analyser needle was as low as possible adjusting the pahase and amplitude until the peaks of one source line up with the troughs of the other source. An adaptive strategy, albeit manually fo rthe optimum result. He implemented it , out in the field, it worked, but only worked loacally. The sound was quitened in one spot but elesewhere it could be louder. We are no longer dealing with sound in a duct, not just 1 degree of propogation. Unless you can get the transformer and speaker to occupy the exact same bit of space you will never get perfect cancellation. You can get local cancellation and you can steer that cancellation wherever you want but it will be worse in other locations. So introducing the concept of monopoles. The simplest sound source you could imagine , a pulsating small sphere, sound propogating in all directions equally. At low f where the waveforms are larger than our noise source like a transformer or speakers, they pretty much act as monopoles. A demo via small closely spaced pc speakers. One a noise source , turn on the control source and the control system initially about in-phase. Tweak the control to antiphase and the sound gets quieter, but not equally so around the room, especially when separating the speakers a bit more. We got cancellation. We can achieve local control using this single channel approach of one loudspeaker, but we make it worse in other areas. For wider control we can try more control sources. It sort of works but it all gets very complicated quite quickly . Achieving multi-channel control is too much for a human to achieve on his own. Much better if we get a computer to do the control . Defining the algorithm, we want to minimise the noise at the microphone, we call tha tthe error signal. Call it error simply because if its big then there is something really wrong with what we are doing. The size of the error signal depends on the 2 adjustable parameters . A maths expression with a power law of 2 in it , being the most important part. A quadratic equation , when you square them and plot out you have a U shaped plot. Our error signal is U-shaped . We turn on out control and we still have some sort of error at some sort of level, we adjust the phase the error gets smaller until we hit some minimum , if we carry on it gets bigger again and a U shape. As with the transformer example we were not just adjusting the phase angle but also the amplitude , our error curve becomes 2 dimensional and we end up with a 3 dimensional error surface of a kind of bowl. 3 axes of phase, amplitude and error. If we had multiple loudspeakers , the error surface then becomes a multidimensional error surface so if 10 speakers then a 20D error surface. Impossible to draw but it exists mathematically. We will stick with 2D for now. A human would not take the best route down the error surface. Pretty quiet, but not the best spot and not got there very quickly. We want a computer to take the gradient of steepest descent. You are looking from the edge of the bowl and deciding which way is the steepest, the quickest way to the bottom. The algorithm is called the filtered X, FxLMS, filtered least mean square, a popular algorithm for active control , in many scenarios. Imagine a car with a noisy engine. Some engines are boomy a lot of low f tonal noise. The noise is propogating through the car , through the engine mounts, through the shell of the car and into the cabin. As the noise propogates it is changed in some ways . Each f of our noise the amplitude will change and its phase will change. We can describe how the amp and phase of each f is changed , put it all together and it is called a transfer function. We want to measure the noise at the engine , feed it forward , through a filter that does something to the noise and plays it out the loudspeaker sounding the opposite of that transfer function . When the 2 sounds meet they will cancel out. We can do that and press play and probably get some cancellation but for how long. The transfer function is a fundctiuon of the complex structure of that car. The engine wil lget older , the engine mountings will change, what happens when there are 2 people in the car, or someone opens the window. In all those circumstances the transfer function will change, so we need some way of adapting it. Like Wm Conover, we stick a microphone in the car , feed it back , tweak our contro lfilter until we reach the bottom of that error surface. If something changes in the car, thats ok, because of the feedback loop doing some tweaking , we get the best control we can. We take a reference that we also measure at the engine and hope the transfer functions work well and cancel out the noise. If they don't , we feed that error signal back , via our microphone and we feed the reference signal forward , combine them , and use that to control our filter. When we do this we happen to follow the gradient of steepest descent. The aviation industry was one of the first areas to exploit active control. The aviation industry is more willing to spend a bit more money to achieve things, compared to car manufacturers. Tell a plane operator that they can remove some of their noise absorption linings , save 20Kg and put in this other thing that is just 1Kg , tell them it will cost X and evert year you will save X in fuel, and they will willing go that way. Fly out of Southampton airport with FlyBe in the Bombardier Q2400 , poropellor planes , they have activ enoise control onboard, the Q stands for quiet. Short haul, prop planes don't get very high and at low altitudes jets are inefficient. But prop planes are pretty noisy. A noise system by Ultra Electronics , was originally developed here at the ISVR with British Aerospace/ BA Systems. On a prop plane, every time one of the blades passes the fuselage you get a big pressure wave. The blade-pass frequency which is say 88Hz for example so a boomy tone. You can't stick a big heavy wall between you and the prop , because its a plane and you want it to take off. They apply this feed forward algorithm , take the prop tachometer signal , an engine mounted sensor telling the rotation speed of the engine, put it into the controller that creates the control signal and feed that out to actuators within the fuselage. When they first developed this there were loudspeakers in the plane, cancelling out the noise . The noise is a function of the fuselage itself vibrating , so now they just put shakers on the fuselage and cancel out the vibration at source so you don't get the noise inside the cabin. They have little microphones in the trim? panels . Next time you're on a plane look for holes in the trim panels , little eyelets are where the microphones are. They provide our feedback system. If you ask the flight attendant , there is a switch, and they can turn it off , whether they would or not , but if they do you can hear the difference. Go the the Ultra Electronics website and there is a couple of videos demonstrating this, getting rid of the low f boom. Without it , you probably would not want to sit in it. Its in the crew compartment of Hercules aircraft, reducing crew fatigue and few other commercial aircraft. Automobiles. Lotus engineering was about the first company to exploit this. They designed the systrem in early 1990s to reduce engine noise in the cabin and then they decided that a/ it was a bit too expensive and b/ Lotus engines sound quite good and didn't want to get rid of the noise. Lotus Engineering still have the system and have implimented it is a few other cars. Simailar system, tacho on the engine, feed tit to a controller, loudspeaker system in the car already there for personal audio and eror microphones i nthe roof. There are other systems to reduce road noise. Instead of taking your feference from the engine you can have accelerometers on the suspension and measure the vibration of the suspension and use that as the reference signal to cancel out road noise in the car. Being developed in luxury vehicles, also in light weight vehicles. As fuel gets more expensive, it becomes a bigger issue and so lighter vehicles. But light weight means rubbish noise reduction. So take out the noise absorbers, make a light vehicle and put in active noise control to reduce the engine noise. A novel use in the automotive field is something called cylinder de-activation. I think an Audi has it . At low speeds they turn off one of the cylinders, from 4 to 3 cylinders, but people don't like the sound of 3 cylinder engines, a clunky sound. If you pay 40K for it you want it to sound good. They impliment noise control , cancel out the 3 cylinder noise and add engine sound synthsis , a sound that sounds better. You could put it any engine you like, so a 2CV with the sound of an Aston Martin perhaps. There is also a push for engine down-speeding . You can design engines that work at much lower speed ,work just as well and use less fuel but people don't like the sound of them so people would not buy them . So again cancel out the sound of the low rev engine and put in a more normal; sound. In developement are new generations of hybrids , some purely off the battery power and then have a petrol engine just ot work as a generator. You can then run the engine at its best possible operation conditions , high loads, but you have a disconnect between the throttle and the noise you hear. The noise is constant or turns on or off , not related to you and throttle use, which is unnerving. So cancel out that noise and supplant with a more reactive noise through the speakers so you feel as though you are driving the car. Noise cancelling headphones. Especially for commutors and travellers. Headphones plugged into ypour personal audio player . A little microphone feeds the sound forward and cancel out the noise from outside. They are mostly analogue at the moment. Most of the previous has involved computer type digital processing. Because you are cancelling in only a very small sound field , very locally you can get away with just some analogue electronics doing the inversion. You can make it a bit adaptive but not as complex as the digital systems. Some work through feed forward with the microphone on the outside , some are feedback with a microphone inside and a feedback loop. I've not touched the feedback systems , requiring a whole presentation for that. Q&A, 30 minutes The noise cancellation stuff works well for people i nthe car or plane , but presumably outside for other people it could be worse? It can but its not that big a deal, because the noise just outside the car is quite loud anyway. And the same with the plane as the propellors are so loud, the difference is minimal. A few years ago I flew on a Cuban Airlines Ileutian plane and I noticed these little things that looked like miniature microphones on the backs of the seats and I thought they were there for a sinister purpose, recording all that was said. But it was by far the quitest airplane I've ever flown on. Jet powered plane. ? If mics were in the headrest then likely there was loudspeakers in the headrest as well. With turbo-jet the noise is quite broadband and that is quite hard to control pver a large area, because you cannot predict it. Tonal noise repeats itself over and over , so you can predict it. To cancel out that source of noise then the canceller has to be close to you and you can only control in that small area. I don't know the system but each seat could well have had individual control. When you were talking about using the fuselage itself to casncel vibration , is there a knock-on benefit that you are reducing stress fatigue as well ? Potentially., The system isn't optimised to do that , you maybe making it worse. Ina vibrating system you get various different modes , which are types of vibration. At a certain f it may vibrate one way and anoth f ,then another mode. Some of those modes radiate better than others. In a mode where one wave is moving forwards and a high pressure at one point and another mode is going backwards and a low pressure you get self-cancellation . Some modes don't propogate into the environment , so the control system isn't aware of them , it can't hear them. so there can be a scenario where you are controlling the radiator modes and you get an effect called spill-over and make other modes work. Such as Ultra Electronics, whatever you put on a plane has to have done thousands of flight hours and I believe they would have tested for that. I've heard that on some modern trains , that they add a system to make the train noise louder for safety reasons , approaching stations they make the exterior noise louder. So if on the platform , you can hear the train coming.? May well be true. It would not be a system like this , you are just projecting noise regardless of the existing noise. It is a problem on electric vehicles. A lot of work to create warning sounds for electric vehicles , so people can hear them coming ,as they are very quiet. Having a befdroom window less than 3 metres from buses that go by, I'm having some secondary double glazing fitted. I've heard that the optimum gap is 4 inches, but when I tried speaking to the bloke trying to sell the stuff, he didn't have a clue, do you? My work when in Melborne , I did a lot of work on glazing and traffic noise. 100mm sounds about right. When you have regular double glazing with a 6mm gap , for sound purposes you may as well not bother. That gap will have a resonance and the sound performance with the f that coincides with that gap will be worse. You make the gap bigger, push the resonance down into the low f where you don't care about so much. Is there much difference between a gap of 75mm or 100mm? At 75mm you may be bringing the resonance up into the range you can hear. Above 100mm is not going to help? Go to 150mm you will probably get a bit better pperformance . Is it possible to have noise cancelling in a mechanical device , like a motor car silencer? THe silencer would make the noise less but an all mechanical device? So a feedback loop with a different propogation path. You might be able to do it if you were only interersted in one f. You will be feeding back all the frequencies and 1 will cancel. As you get further away in f you end up making those f louder. You would need to change the length to change the f . The Bose white cube audio units they have an internal tube that exis at the rear of the speaker and part of that is trying to create reinforcement at certain frequencies to improve the bass. Car silencers , they seem to have done a very good job over the years. A car running around without its silencer , having dropped off, its a horendous noise . Imagine all cars going around without silencers, so those baffle systems do a good job at attenuating multiple explosions. You could not do that amopint of silencing actively, for the price of a bit of metsal tube. On the noise cancelling headphones, is there any chance that a person could have the level up so high that they could do hearing damage, with the added power of the cancellation signal? No because you are cancelling out the pressure, the amount of acoustic energy that reaches your ear, is smaller. Also because you are making the ambient noise quieter , you can have your music quieter and still apprecieate irt. On the headphones I work in a noisey environment, a data-hall, which ids a mixture of white noise and ventillation noise and I find Bose noise cancelling phones are brilliant. They claim that it allows you to understsand speech and they seem to do that. Is that a notch that they are less effective at or is there something more behind it? Without knowing exactly the technology I would imagine its because with the adaption process of the feed forward , that filter will adapt and perform as best as it can. With nice steady noise like data-centres or jet engines , it adapts and sits there . When someone talks it does not have a chance to adapt quick enough so that talk sound does not get cancelled out. Industrial ear defenders work well at killing loud motor noise etc but you can still hear human speech with them on. But they don't compare to active noise cancelling headphones. Your hearing is quite well tuned to hearing human speech, it is much better at picking up noises that change. When wil lthere be a system that could accommodate the sort of intrusive noise from the likes of downstairs, during these talks up here? Noise that is not repetitive, noise you cannot predict , there is a physical limiut to the level you can control it , and the amount of space you can control over. A tonal noise is the same repeated, no prediction required. There are equations for this and the higher the f and greater the space then less resulting cancellation. If the source of non-repeating noise is further away, does it make it easier, more processing time available? Not for that reason but if the source is further away , it tends to mould into one and tend towards a steady burble, you don't hear particular noise events , and approaches the sort of noise of a jetengine or datacentre. How can you reduce the noise in a flat where an upstairs toilet flushes ? (Reference in the speaker's preamble/biog) To achieve the Australian building standard you have acoustic lagging , heavy lead sheet with foam on one side and you wrap it around the pipe. So pipe then fibreglass/foam material , then lead layer, that is all in an air gap with fibreglass in that as well. Then plasterboard over all that. Whast was the difference for that technique between lagged and unlagged in dB? I don't know off hand , depends what your flushing ;-) If we move the Australian building standards to large old English houses with noisey plumbing systemms , would it be affordable? Probably not , your pipes will not be isolated it the right way. You have an acoustic path where noise from the pipe travels through a wall , the pipe is clamped in lots of places. You can deal with the acoustic path but the hard clamps to the wall is a problem. You also will have brick walls and not a stud wall with cavity that you can put things in. Will I notice any difference from your great works going about my general life? How different will things be in 10 years time? a nice quiet world? Yes. Especially if airplane noise annoys you . Rolls Royce have a technology centre at the ISVR , spending a lot on making their jet engines quieter, because it is such a big issue. The way noise contours are measured around airfields is problematic. If you make the engines half as loud you can double the number of flights and still meet the standards. Then is it the frquency of flights that annoys you or the level of one flight. If you heard an engine of 30 years ago , you would certainly notice the difference. Do you know what the technology is of noise cancellation in planes where it is cancellation everywhere not just the cabin? They don't use noise cancellation , just noise absorbtion. Changing the shape of different parts to change the flow. With a jet engine you get tonal noise from the rotating fans , and when rotor ppasses stator there is a pressure wave and tonal noise . There is also jet noise which is due to the cold air and the hot air mixing and that does not come from the engine . So for a high-bypass turbo engine onan Airbus or whatever a lot of the noise is coming from 70 metres from behind the plane where the mixing causes turbulence and then noise. Is there systems that can reduce that noise? Not active systems, they try to regulate the mixing , less mixing , there is less turbulence Currently 7am planes from Southamptonm Airport have to observe noise abatement procedures, do you happen to know what physically that is? No. (From the room) Its the route they are forced to take There is a new sytem of open rotors that they are developing , two contra-rotating propellers , driven by a jet mechanism , very fuel efficient but they are really loud . Until they work out a way of making them meet noise regulations they can't use them . A lot of older planes have been banned from flying in UK airspace unless they have hush-kits fitted. They are always changing the regulations, fix a problem to meet the regulations and then 10 years later there is a new regulation to be met. (notes Matlab used for the ppt animations but freeware Scilab and Octave probably similar)

From Fermat's last theorem to a million dollars (and many other places besides) Jim Anderson, Mathematical Sciences, University of Southampton Science Cafe, 14 October 2013 3/4 hr talk, 3/4 hr Q&A, 34 people (in the below, as ASCII, ^ means raised to the power of, and * is times by, / is divide by) Normally no questions during the talk but this is a maths talk As I tell my class, if you through soft things at me , you'll get my attention. Through hard things, you'll just hurt me A quote from one of the better American expositers of maths Paul Helmers? who when talking to a group of mathematicians about giving talks to mathematicians " It is impossible to say too little in a math talk" No matter what you say there are people who will not keep up with you. i will try to not violate tyhat this evening but if I do, let me know and I will be happy to explain everything. I will start with something I think we all know, taking one step back from Fermat's last theorem (FLT) and go to beyond the boundaries of human knowledge at least twice over the next 3/4 hour. Take you from what you were comfortable with as school and saw and know to the realm of the unknown and talk a bit about what is going on. Beginning with hte Plimpton 322 a Babylonian clay tablet roughly 4,000 years old , although my Babylonian numerology is non-existant , it is listing triples of numbers that are 3 sides of right triangles. So back 4000 years to the The Pythagorean theorem, the theorem as we know it is only about 2,500 years old and lots of proofs . As far as I can tell it is the oldest significant fact that we have. A right triangle , with a 90 degree right angle to it The lengths A, B that abut the right angle and C the hypotenuse of thesides of a right-angled triangle satisfy A^2 + B^2 = C^2 This relationship holds for EVERY right-angled triangle, whether the As,Bs are integres or not , most of the time we wil lbe talking about wwhen A,D and C are integres but towards the end of the talk we will allow ourselves to drift beyond that realm. I was talking to my colleague coming here this evening about how mathematicians think about things. They like to have ?, they like to take observations that we know , look around, take things that we see , abstract away everything practical, recognisable and concrete about them nd see what we are left with. This relationship holds for every rt tringle. A priori, if we didn't know anything there is no reason to believe that there is a single relation that the 3 sides of a rt angle triangle satisfy regardless of the triangle and yet we have one. I won't proove the PT , I hate to say this but Wikipedia tends to be pretty good abouyt maths , there ar ehundreds of of PT. A lot involve taking a shape whose area we can calculate easily , breaking it into pieces where the pieces are either triangles all of the same size or things we can calculate the areas easily and then a bit of addition. There are 2 proofs due to James Garfield , the 20th president of the USA, usually only heard of because he was assisinated 7 months into his term of office. And sadly we lost his mathematical genius, he came up with one of his proofs while in discussion in Congress which is a far cry from the sort of political debate we have in the States these days. The first formal PT proofs given about 2500 years agoby Euclid. I give myself license to do 2 things , license to lie to you , not about big things, just about little things and I give myself license to tell you things that you already know but giving a talk to an audience where I know nothing about them other than they go to a pub , makes it difficult to plan too far in advance. Back to the triangle and 3 side lengths , called a Pythagorian triple because they satisfy the PT. As with proofs of the PT there are gazillions of facts. We can figure out what they all are, which in itself is a remarkable fact. We can figure out every Pythagorian triple that exists . So hand me 2 numbers u and v for integers u > v > 0 and A,B, C triangle Take A to be u^2 - v^2 and take B to be 2uv and take C to be u^2+v^2 then that is always a pythagorian triple . Do the math , square A, square B and squre C a Pythagorean triple, and every Pythagorean triple arises in this way. S o a complete list, and mathematicians love complete lists. 3, 4 , 5 is a primitive P triple, I can multiply everything by 2 and another triple , or by 3 etc but 3,4,5 is primitive , with no common factor. The primitive one are what we are interested in . It does not matter how big you make them , primitive ones. Picking u and v without common factor , get a primitive P triple . The largest number that always divides the product ABC of the elements of a primitive (no common factors) Pythagorean triple (A; B; C ) is 60. We don't know how much the Babylonians knew about the PT, we know they had examples including one that is a mistake , be generous and asume it is just sa transcription error on someone's part . They had a number system based on 60 , 60 seconds in a minute and 60 minutes to an hour , that goes all the way back to the Babylonians . Here we have anoher example of 60, did they like 60, rather than knowing of Pythagoras , not pulling it out of a hat. 60 divides a lot of ways and you can do lots with it. I can fix the lenghth C and ask how many triangles I can draw where I have that same hypotenuse. Some long and thin , some fat and find as many of those that I want, different slopiness. For each positive integer n, there exist at least n different Pythagorean triples (A; B; C ) with the same hypotenuse C So give me n=1000 and asked me to find 1000 P triples I don't know how big that hypotenuse would have to be, I suspect it would not be enormously huge, but I can't figure it out on the fly. There exist infinitely many Pythagorean triples (A; B; C ) in which the two legs A and B differ by exactly one; 3,4,5 is one , 5/12/13 is the second P triple does not count because I'm not using the 2 legs A and B but I can stil lfind infinitely many as in 20/21/29 , the A abd B differ by 1 . If they differ by 1 then they cannot have a common factor, they must be primitive. Plenty of nods around, have I taken anyone out of their comfort zone? OK. I probably won't with hte next slide either. So as a mathematician , we take something we know plenty of primitives, know how to prove it, life is good, we know all we want to know, or at least an enormous amount of what we want to know. How can we twist the question to get something else . What is special about the 2. We can change the exponent in the Pythagorean theorem, but preserve the fact that the exponent is the same in each term. For an integer n = 3, there are no solutions in positive integers A, B and C to the equation A or n=4 This leads us to Fermat's last theorem stated 1637, as most of you probably know, in the margin of one of his books , a translation fronm a Greek mathematician Thiaphantis? made the statement that there are no solutions for any integre exponent of 3 or bigger and that he had a truly marvelous proof of this fact but the margin was too small to contain it. For 350 years since then , mathematicianms speculated on what that truly marvelous proof was. I was one of the editors of a math journal a few years ago , and what you get with some regularity are people who claim to have found this truly marvellous proof. There was another journal where they had preprinted cards saying thank you for your proof of FLT , your first mistake occurs on line (blank) of page (blank) and send it back. There is some speculation that we think we know what proof that F had. It is a truly marvelous proof but it doesn't actually work , it is wrong. It makes an assumption that turns out not to be true. Make that assumption and you get a proof in 3 or 4 pages. We also know that he did not care an enormous amount about this quaetion , because he lived for another 15 years after this marginalia and never wrote another word to himseldf or anyone else about this question . But we as mathematicians took it seriously , because although F was a lawyer and not a professional mathematician , was working at a time when there were no pro mathematicians , just amateurs. He was part of a group of talented amateurs , who wrote to one another . Saying such as here is something I know how to do , can you figure out how to do it yourself. they would tease each other in their circle. This is not one he ever sent around. Everythng that he sent to the others or he wrote in the margins where he said he knew how to do it, then within 10 or 20 years someone figured out how to do it and he was right every single tiome . Where he said, maybe , hedged, he was right about 50/50. After 20 years this was the only question left. Its spawned at least 2 fields of maths , destroyed the careers of hundreds of potential mathematicians because they'd get sucked into it and never come out . But eventuallly resolved 1995 by Andrew Wiles ,originally 1994 Brittish mathematician (M) working at Princeton, announced a proof, people then found a gap in the proof. With , I think, Richard Taylor they fixed the gap and in 1995 it was accepted that Wiles had prooved FLT. But he had not proved it directly, there is no way to call his proof short , because in mathematical terms his proof is equivalent to going from here to London via Moscow. In the 80s there was a group of M such as Gerard Fry and Ken Rivet? who had made connections between a much bigger harder and less solvable question , the Shimura Tanyiara Vey ? conjecture STVC , if I explained it , it wouild be a lie . It was a massive question. If you had a counter question to F , if you had a solution an A,B, C and positive integre n for A^n+B^n=C^n then you could construct a counter to the STVC. Wiles proved enough of the STVC to show that that could not be done. You could not have a counter example to F, so FLT had to be true. But its not really slick. If you want to find more on F eithe rfind on utube the Horizon doc with Simon Singh or read Simon Singh's book on FLT because it is one of the best books on math for a general audience that I've efer seen - a superbly good book. In the doc, that came before the book, Simon Singh is a particle physicist who understsnds math enough to know how to explain it to non-M. One thing that STVC involves is modular functions and there is a beautiful moment in the doc whee they go to the greatst Ms alive today , and asked them if they could explain in one sentence, for sa genertal audience, what one of these functions is and they just go , no. Then you get an explanation that doesn't really help and not much sense so not where we will go. Now we have gor to F , I want to go 1 step beyond. There is another way of generalising beyond letting the exponent get bigger than 2 but keeping all the exponents the same , is letting them get big but letting them be different. So what if we loosened the restriction of the exponent of each term having to be the same, where do we end up. We end up at the milliuon dollars . There are 7 problems worth a million dollars each 6 current ones, offered by the Clay Mathematical Institute which was funded by a rich amateur M , named Clay, businessman who liked his math . Gathered a scientific committee and picked 7 questions in the year 2000 and these are questions he wanted to give people an incentive to solve , so each is worth a million dollars. One of the 7 has been resolved , the Poincare was resolved a few years ago by a Russian M called Pearlman finishing what was started by M named Hamilton in San Diego in the 80s Pearlman refused the prize and refused the Fields medal which is the highest award a M can get. He did not want to get political, doing math for the love of math Clay Millenium Prize Problems 1. Poincare conjecture - resolved and awarded 2. Birch and Swinnerton-Dyer conjecture (where you would go after F in a different direction , again difficult to explain other that it is number theory, but not numbers as we know them) 3. Hodge conjecture (geometry of how things are put together ) 4. P versus NP (a question about complexity , basically the difference between how hard is it to solve a problem , to build a black box to solve every example of a certain sort of problem versus how hard is it to check whether what I have given you is actually a solution. There is a difference and the question is how far apart are those) 5. Riemann hypothesis (again about number theory, around for 150 years . If this hypothesis is true then half of current number theory is true , if it is false then the other half of number theory is true, but we can't have both) 6. Navier-Stokes equations ( what we believe govern fluid flow , how water flows through a pipe , what happens in a river . In 3D we do not know wheter the equations we have writen down , formally have a solution. So say something about that, its worth a million dollars) The hourly rate on each of these questions will be low , way below minmum wage low 7. Yang-Mills theory ( a M physics thing that is unrelated to the Higgs Boson , tharts as much as I know) The money is waiting , all we need is volunteers to solve the 6 of them There is a seventh, due to Andy Beal . He is from Texas , he's a poker player . At one point he challenged the best players in the world to play for stakes that made the pros turn white. Thet were playing for 100,000 and 200,000 dollar blinds , each person sitting down with a 10 million dollar stack and he beat most of the pros that he faced. He is also an amateur M and in 1993 befor eWiles announced his FLT proof , Beal came up with a conjecture that is a sort of far reaching generalisation of F. If the exponent is 2 we have infinite many solutions. Make it 3 and suddenly we have none. That is a big gap from infinitely many to none. Even for a M going from plenty to scarseness , is there a middle ground. If we let the exponents be different and must be at least 3 . I f I don't then we have lots of examples If we drop the requirement in Fermat's last theorem that the exponents all remain the same, then what happens? Beal's conjecture (stated 1993 by Andy Beal, still unresolved): If there exist integers A, B, C , x, y, and z >1 with A, B, C >3 so that A^x +B^y = C^z similar to what we've been dealing with but now loosened restriction , we get lots of solutions to this equation. They all have the same basic property in common then A, B, and C have a common prime factor. For instance, we have that 240936^7+ 401560^7= 80312^8 The exponents are all at least 3 but the 3 numbers are all even so they all have 2 as common factor. In fact they have 2^7 as a common factor. We need the condition on the exponents, because we also have 7^3+13^2= 2^9 We have a situation laying between the infinite and none of FLT. They obey some sort of rule, we need some sort of rule , because we can have solutions to this equation that don't obey any rule if we allow the exponent to be 2 in one case. If you solve this problem , there is a million dollars, not a hypothetical million dollars. The prize originally in 1993 was 10,000 dollars , then upped to 200,000 and this year on the 20th anniversary he upped it to 1 million dollars. The American Mathematical Society has it , holding it in trust. He's paid out the money, he is just after someone to claim it. Again the per hourly rate is really going to suck. This , already, is something we don't know. We have ventured into the unknown, we have passed beyond the bounds of what we as a species have figured out how to do. We need the condition on the exponents, because we also have. If Beal's conjecture is true then Fs is true trivially . In F the x,y and z are the same and if I have a primitive to FLT it will be a counter example to Beal's conjecture. The A,B,C have no common factor , the exponents are all the samne that would be a counter example to Beal's Conjecture. So Beal implies F. F took us more than 350 years to do and its a tiny piece of the bigger conjecture by Beale. We also have this other conjecture that took a mere 150 years to resolve , almost but not quite contained within Beal's Conjecture, mostly except for 2s. 8 and 9 have a beautiful property beyond one is 2 cubed and the other is 3 squared. It is that 8 and 9 are powers of different things AND 8 and 9 differ by 1. 8 being a power, 9 being a power and 8 and 9 differ by 1. Catalan's conjecture (stated 1844, resolved 2002 by Preda Mihailescu). I have to exclude the power to the 1 otherwise something to the 1 and add is not really interesting question. Even if one exponent is 1 then again most of us could get through that one. The only two proper powers of integers that differ by 1 are 8 = 2^3 and 9 = 3^2 Let the exponents be at least 2 is what I mean by a proper power, then the only 2 powers that sit next to one another on the number line are 8 and 9. They are the ones we see almost right away and we never see anothe rone however far we look. Proving that something never happens is rather difficult . Proving sonmething does happen is easy , just find an instance where it happens and you are done. You have to check everything . I have to have a way of checking everything, a systematic argument to check every single possibility. So I cannot just list everything , I have to do more, must have an argument that works. For Proof, Ms talk about persuading a sceplical audience and I will try and do that at the end of the talk. I won't give you the proof of Catalan's Conjecture because I have no idea why it is actually true. Number theoory that is harder than I can deal with, because I'm not a number theorist, I just love these sorts of questions. Al lthe questions so far have a common theme to them. The Pythagorean theorem, Fermat's last theorem, Beal's conjecture, and Catalan's conjecture are all examples of Diophantine equations. Does a polynomial equation have a solution in integres. Something to a power plus something to a power plus 3 times somethingto power equals something else to another power . Add them all up and ask when is all that zero. Could be susbtracting , like rephrasing Pythagoras as C^2 - A^2 - B^2 = 0 Hilbert's tenth problem (stated 1900 at the seconfd international congress of M), (resolved in 1970 by the combined efforts of primarily Martin Davis, Yuri Matiyasevich, Hilary Putnam and Julia Robinson) . Hilbert wanted to give some direction to these undisciplined cats that were wandering around everywhere. Given a Diophantine equation with any number of unknown quantities and with rational integral numerical coeficients. To devise a process, a systematic procedure, an algorythm according to which it can be determined in a finite number of operations whether the equation is solvable in rational integers. A yes or no , even if it gives no way of finding them. Had to wait to 1970 until that collection of M. Alas, no single such black box exists, and so we have to approach each such question on its own terms. Here is a polynomial , does this thing have solutions . Either we relate it to one we've aleady resolved , piggy-backing or we might be venturing into the wilderness, like Beale's Conjecture. I will throw in another one , no prize for this one Personal favorite Diophantine problem, it is really simple , it doesn't involve Xs, Ys and big exponents Markov conjecture: A solution in positive integers to the equation A^2 + B^2 + C^2 = 3ABC [as easy as ABC ;-), there are no good math jokes ] The question is not are there solutions because we know there are solutions . If I give you 2 solutions and I just order them so A > B > C , if I flip A and B, and A and B on the other side I get the same equation, I have symmetry, change either 2 variables and I don't change anything. Then I give you another solution with the same value of A so A , B', C', where A>B'>C', then as the As are the same , B=B' and C=C' So not is there a solution but rather , if I know the biggest of the triple, that determines completely what the other two have to be. And we do not know. People smarter than me have thought a lot about this question but cannot figure it out. This turns out to be a question of types of curves on particular sorts of surfaces and how many there are of the same length. And the fact that there are at most 6 of the same length. And this is encoding the question in geometry. Here is a question about numbers , should be easy as we've only got squares, how hard can it be, Pythagoras was easy and yet. How can I rephrase my question to make it almost completely different . Graphic of completing a Pythagoran triangle out to a rectangle and a diagonal of the rectangle . Pythagoras is telling me I can build as many rectangles as I want , the lengths of the sides of opposite corners and the diagonal are all integres. What is special about 2, rectangles live in 2D so crank up the dimensions to 3D. What do I get interpreting PT and go up to 3D . Take a shoe box . Does there exist , I only need one example to answer this quaetion. Does a regular , non-slanting shoe box exist wher the length of the 3 sides to be all integres and the diagonals that go across the 3 sides (top = bottom , L=R, back = front)to all have integre length. And I want the diagonal that cuts through the middle of the box to also have an integre length. So all 7 lengths are all integres, no one knows. Like Beales' , Google has some spare computer power , have determined that if there is a box , it is big. If there is a counter example to Beales , it is big, numbers too big to hold in ones head big. 8,9,12, 20 digit big sor tof size. There is a chance that making one dimension 1, the box would not fit in the univdrse. It might be that big, how can we tell. How can we determine if something wil lfit in the universe. Even if we can do it for a 3D box , I can ask about a 4D box , 6C, I can keep cranking up the dimensions with my ADD1 top my dimension handle . Make it as trans-dimensional as I want and each time I go up a dimension , the question gets way harder. Until we can work out for 3D , its not worth asking about 4D etc A different direction entirely The existence of uncomfortably poorly behaved numbers. Up to this point we've been taling about integres , from integres we can get rational numbers or fractions . The Greeks considered, are there numbers that are not fractions, no matter how big the numbers are. Out of PT we get the answer yes. but the Greeks did not like this . They did not want to admit that what we now call irrational numbers can exist. The legend goes that the guy who was to let out the secret got taken out to the Mediterranean and drowned for intending to or actually speaking out. I want to end with a proof I want to persuade you of something that you may or may not want to believe and I don't care if you want to believe it or not , tsake you through, step by step and at each point you will say yes.yes I see how to get from here to there . In the end I want you to say I don't like where you've taken me. Thats what I do to all my students, taking them to places that they don't necessarily want to go, but is ultimately good for them I want to show that the square root of 2 that is the length of the hypotenuse of a 1,1 side length right triangle , whatever we call it is a geometric thing , we can see it , we can draw it, we cannot deny it exists but it's not a fraction of integres. I'm going to get a contradiction and that wil ldemonstrate that I could not have done it in the first place. I make an assumption, then I follow , step by step , making simple steps of logic , leading me to a point which I canot deal , which means my stsrting point had to be false. The beginning is that I can write the square root of 2 as the quotient of two integers. Where the 2 integres do not have a common factor , if they do I just cancel it out. Repeat until there is no common factors. 2^(.5)= p/q or square root of 2 = p/q square both sides 2=p^2/q^2 Move over sides by multiplying by q^2 p^2= 2x q^2 p squared is twice something so it is even and if I have a square that is even then I have a square that is a multiple of 4, because if p^2 is even , that tells me that p has to be even and whan i square an even number , that is a multiple of 4 so cancel the 2 as they are both twice something we can write p = 2P Our equation then becomes 4*P^2 = 2* q^2 divide by 2 each side 2*P^2 = q^2 However, this tells us that q is even, which violates our initial step that p and q have no common factors. But I got rid of all the common factors to start with so that cannot be, it violates what I started with. Which means that the only assumption that I made, the writing of the square root of 2 as a fraction has to be false. Because if its true it leads me into a logical cul-de-sac from which I will never excape. Which means we cannot write the square root of 2 as a fraction. Doesn't matter how hard you try , doesn't matter how big the numbers are that you use , you cannot write 2^(0.5) as a fraction. Ever. You cannot write Pi as a fraction either. I hope I have not violated , too badly, Halmer's Edict , of never say too little Q&A Obviously you are a pure M can you give me examples of where somebody with an application has thought ah yes that is just what I need too. Among Ms we have a canonical example of that . G H Hardy was one of the most prominet Brittish Ms of the 20C , he worked in number theory , which is the larger area that contains FLT etc, the properties of integres. He explicitly stated that one of the reasons he loved working with number theory was that there would never be any practical application for anything that he ever did over the course of his entire professional life. And yet we now live in an age where the underlying math for every way of encoding things , every cryptographic system we have comes back to number theory things. So in effect not only diod Hardy help give birth to the mathematical foundation to encryption , and have his spinning in his grave, but how it is used by governments etc. Not many examples that are as good as that. I ended up in a project a few years ago where a biologist asked a question, about is it possible to construct , if I look at a piece of DNA that is say 5 base pairs long and I want to build a big piece of DNA that contains every piece that is 5 long and I'm allowing them to overlap , what is the shortest possible string and how can I build it. That is something that can be answered using somrthing called graph theory. You can construct one efficiently for all lenghts 5 and much less efficiently if it is of length 6. Just because of how things are built. Experimentall y they could find of length 5 , but not able to do it for 6 . We were able to say exactly why and give an explicit way of building them. A bit of math that is not immediatley relevant to that bit of math. Its a really stupid question There are none . Can computers solve algebra and geometry and are there any constraints as to how far they can go with it? Computers can write down mathematically correct statements, most of which are rather uninteresting. If I was to take a proof such as Wiles proof of STVC , we use an enormous amount of shorthand because we say , since we know this , we know that. The this to that could be what someone else did over the course of their entire life. If I tried to reduce everything back the basic symbology of logic the bumber of things you have to write massively explodes. Computer ones tend to be very short relative to the things we want to do. What computers are doing is they are fornalising ways of checking whetgher proofs are correct. Proof Theory - you can take some of htese complicated results , encode them in a way that the computer can check that you have a correct proof. A third way - example is the 4 colour theorem . Take a map , you can ask the question is it possible to colour each country with a colour so no 2 countries with a common border, are the same colour. And what is the smallest number of colours that you need. Mapmakers knew that it was 4 , known for centuries , but not till the 1970s could Ms prove it. It was the first major computer assisted proof. If we knew it was true for say 10,000 small examples then we would know it was true in general. If we had a big counter example we could build a small counter example and they got a computer to list and check all of those 10,0000 cases . Then our big theorem is known to be true. A lot of Ms really hate this , because it gives us no reason as to why it should be true. If I knew that my answer was true for this 1 million set of examples then I would know it was true in general. We don't have autonomous proof constructing computers out thrre yet. There is a 1950s SF novel called Collosus by D F Jones where that happens. They build a computer to control the defenses of the country , it becomes self aware, realises the Russians have one, they start talking to each other and start talking in math . In a few hours they have gone beyond what humans know and then they take over the world to protect us from the Matians. We don't have that sort of computer yet. Not impossible that in 30 years we may see that sort of thing happen. Computers can check , do enormously complicated calculations and simulations , do the case-checking that we don't have the time or ability to do by hand , to assist us but they're not yet leading us. As far as I can see with FLT there are 3 possibilities , 1/ he had a very neat proof and it was correct 2/ he had a neat proof that had an error in it 3/ or he left a joke for posterity Which do you think is likely? I personally think he had a neat proof with a mistake in it. Because after some of the smartest people on the planet , poring over this qiuestion , for almost 380 years . If there were a slick proof someone might have found it by now . Also he wasn't the sort to tell a joke , he was a lawyer. We have a plausible scenario where he thought his proof works , where we know it has a hole , we at least have the possibility of believing that he could do it, he didn't , he realised late rit didn't work . Or maybe he just completely forgot about it. Its not that interesting a question, except for the fact that he said "I can do it , ah , ah , can you" and his laugh echoed through several centuries of history. I think he had an idea that was wrong. Are still people trying to do it? Oh yes. There are even some serious peoiple trying to do it. There are several questions. FLT and The Goldbach conjecture which says that every even number bigger than 2 is the sum of two primes . People keep submitting proofs to journals . You start to read them and you realise the author is using a definition with which tou are not familiar and it gets more complicated from there . Or tri-secting an angle with straight-edge and compass that we've known for several centuries to be impossible but people still submit proofs of how they can do it. Its hard to know what to do other than "your manuscript is not quite right for this journal at this time" we wish you hope in submitting it somewhere else , perhaps this place ( that we don't really like) I think Newton invented Calculus because he needed it , Georges Boule invented his Boulean maths, when wa sthe last complete area of maths that was invented and how many more do you think in the futuire to be invented? Most Ms would say that calculus is not yet complete because in effect the Navier-Stokes equations is really just very complicated calculus. There are no areas that are complete I would say. There are areas where the questions have become incredibly complicatred, technical and uninteresting but they are still there. Group theory was invented in the 1820s out of the study of symmetry . An area called Algebraic Topology was born in the 1950s and still much a subject of interest . A lot of the mathematical physics like string theory and super-symmetry are of the 1970s and 80s and those are having a fruitful conversation between the Ms and physicists. We keep coming up with new areas because people keep coming up with questions beyond the bounds of what we know. Like parks in a city we always have semi-wild area to explore , where we haven't quite filled everyrhing in. So no new branch of maths since the 1970s? I suspect I know people who would take issue with that , but I canot come up with an example off the top of my head. But a lot of the current things that are being developed are not new fields on their own but connections between 2 areas that we didn't think were connected and we've brought them together and that has moved to a fruitful branch of research. So geometry and algebra , start treating algebraic objects as geometric objects and bounce them back and forth and learn a lot about each from the other. We have a question hard in one and easy in the other and vice versa and that is what a lot of people in the pure maths do , the bouncing back and forth. Any branch of maths, you look back and someone has been there but not dealt with it in a systematic way. Like the Babylonians and there list of Pythagorian triples we don't know what methosd they used to generate them Or even why they were doing it? We think we know why , as they are useful in surveying of buildings but we don't know if they had a very general formula for doing it or finding them in an ad hoc way. They only wrotre down the tables that work if you happen to need them Its entirely possible that there is an ex[lanation in some box in the basement of the Brittish Museum not catalogued yet. Going back to the A cubed + B cubed plus C cubed = 3ABC and you said there was a geometric connection, could you go into more detail? The Markhoff conjecture . There are 3 basic shapes of surfaces. One is flat, one is round like a sphere and the third is a saddle, bending up in one direction and down in the other. These aere surfaces where at every point I have a saddle geometry, bending in 2 opposite directions. On surfaces like that , we have a lovely property , take a piece of string and loop it around and knot it. I can shorten it until I cannot make it any shorter, can't shrink it to a point . For any curve I can find a representative curve which is shortest, a geodesic . I can also ask for the geodesic to be simple so no figure 8s, no crossings. What the Markoff C is sayiong , that on a very particular surface known as the modular-taurus ? which looks like an American dough-nut with a single point removed, there are at most 6 simple closed geodesics of any given length. There is a much more general C that says there is a number, which we do not know, that if I take any one of these surfaces and i look at the simple closed geodesic of a given length there are at most that many of them. No one has any clue hows to do that. I think that is getting too technical than a pub warrants. I'm not a M , there seems to be a great focus in all these of involving integres, and positive integres. You said about abstracting further, what about non integres ? The reason we stick to integres is if I look at non-integres I can always find solutions. To look at non-integre solutions we tend to look at the solutions as a whole and try to understand the shape of the set of all solutions. A field known as algebraic geometry , where polynomials ? and algebraic geometry is actually very hard because weird things happen . For example if I look at the equation x^2 = 1it behaves very differently to the equation x^2= -1, over the real numbers. One has 2 solutions and one has no solutions. But from a M point of view I just have x^2 = number and I have to start understanding the eqution in terms of the specics of the numbers I'm using to define the equation. And that gets complicated . So we restrict ourselves to integres it makes our life a lot easier. Even for the questions where we don't know how to do , it restricts us to a few possibilities rather than looking at these very complicated shapes that arise when looking in more generality. Which we can do , but looking at integres it is called number theory and the more general case it becomes algebraic geometry , the two camps talk to one another but they say they are doing very different things. A difference of degree than of kind -ish , maybe. Its the room next door . The equation with 3ABC on the right I could not read the slide? I have numbers A, B, C where all squred and added = 3ABC , and I've ranked them so a is the biggest . If I know A then I know what B and C have to be. Compared to PT, for some values of C , I could find lots of values for A abd B that give the same C. THe Markhoff C says this doesn't happen for the sightly different equation. The biggest one there determines the othe r2 , with PT the biggest no way determines the other 2 I could not read the heading? The Markoff conjecture, the same Markhoff as Markhoff Changes? he was a busy guy, I think it was the same guy Probably a stupid question There are none , just ones that are unasked. Why 3ABC, not 4ABC? Its what came out of the geometry. Translatred into number theory because the thinking was , it must be easy to solve this number question. It turned out we couldn't . We as me and my colleagues care about the geometry. If I write down a random polynomial and ask are there solutions , it will in general be a hard question. The bit about Hilbert's tenth problem , there is no general way of attacking these questions . Each one we have to start at the beginning , is it something, is it not , we have to throw everything at it. We were thinking of the geometry and that is the numbers we ended up with. Your 3D box, were you not interested in the face-plate?, the 3 sides and the non-diagonals,. a squared plus B squared plus C squared, does that have solutions? Yes. If you look at the 3 side lengths and the diagonal through the middle or if you look at the 3 side lengths and the 3 face diagonals you can find solutions. Its just when you put them all together its that one constraint we have not figured out how to resole yet. The numbers are bigger than googleplexes? you mentioned Google as using some of their computer power I don't know if we've got as big as googleplexes yet. A google is 10 to the hundred and a googlplex is 10 to the google. The last I heard there was only 10^80 particles in the known universe. There is an article I read a few years ago where I read there are questions where we know the answer is no, statements we can make that we know to be false, but what if the smallest counter example is so big that it won't fit in the known universe. If we couldn't express the counter example through any known notation. Can we work with a logic that is locally right even if globally its wrong. It gave me a headache. When you start talking about practicalities you run into that question. If the counter examples are so big as to be meaningless , does it matter. There have been counter examples that have come out of computing power? They're massive. Its between 3 and whatever number of particles in the known universe. Its somewhere in there . To me that is a copout. There were loads of proofs of Pythagoras .. elegant .. that is the absolute proof even i n another universe . In a bigger universe where they had room, a lot of my colleagues would agree. ... ? If I make an assumption that is false, I can prove anything. If you have an impractical example ? I',m not saying it doesn't matter to me as I tend to be a purist about these sorts of things. True is true, false is false and the size of the universe is irrelevant. There are logicians who specylate about can we deal with local logic .Its not something I'm going to enter into other than to speculate in a pub. I never hear of the phrase reduccio ab absurdam , is it because I live in the wrong circles . In 40 years I don't think I've heard that term? We tend not to use the term any more because people don't know Latin these days. Its called Infinite Descent? often I've never heard of that term Or just Proof by Contradiction, or contra-positive or that sort of thing , depending on the specifics of the case. I did once have a student come to me and ask what a priori was, he wanted to know what (single) priori was. Thats in all those CSI programmes In regards to the 4 colour map colouring. You mentioned this was proved by a thousand test cases. The test cases were to represent all possible maps because otherwise it was just a probality.? They said if we have a big counter example , we could prove that our counter example has to have a size and found how big the counter example would be. Then all they had to do was test all the counter examples of that size. Do it for all those and none were counter examples . We can't have a big counter example because if we had a big couner example it would give us one of this bounded size. It did take a long time for a lot of people to accept it because you had to assume they had listed all the cases correctly , generated in the computer correctly and what the computer had done, was actually right. So you are asking the computer if its right and you've told the computer what to say , round and round, the checking of that was very important. That basic method has been used for other things. The Kepler Conjecture that globally the best way of packing cannon balls is one of 2 standard packings and again the proof of that is computer checked and works in the large. That is still somrhing that a lot of people are unhappy with. So the reducing is the clever bit and the rest is saving yourself legwork? Sometimes if there is enough legwork, its not clear that we can actually pull it off unless we had a lot of grad students. You have to prove the bounds of your problem and then reduction to the appropriate point ? Before you can do anything else . That is going to become a more common method now. We are getting more sophisticated computing power and more sophisticated ways of using it. That argument that I can reduce it to so and so and then fit it in a computer is going to become a much more powerful style of argument but it wil lrely on us trusting what the computer is doing, is complete and correct. So verifying that will become much more important. Which means the formal business of using one computer to check what the othe rciomp=uter is doing what it says will become much more important Do you feel that ....? I like to be able to have one sentence or a paragraph giving me a reason to believe it is true. And because the computer says so , is not yet sufficient for me. Because we've reduced it to this gruesomely large number of cases that we then checked one at a time , its not elegant. Its not aesthetically pleasing , I like elegance , I like the very beautiful proofs . I think that the proof of the fact root 2 is not a fraction is a beautiful proof, you need every bit in it , jus t a beautiful little proof. So do you believe there is a more elegant solution to the map problem? There is a very elegant solution to the 5 colour theorem . Its something we teach in graph thewory to undergraduates. When you have the notation you can do it in a single lecture. Beautiful proof that does not work for 4 , it cannot be made to work for 4 . You can't take the proof for 5 and make it a proof for 4. So you need to do something different . And we have not been clever enough to figure a way of doing it differently other than reduce it to a number of counter examples and check them all. Maybe someone will come up with an elegant proof. Maybe its just a problem that does not havre an elegant proof , maybe looking in the wrong place. Maybe the elegant proof comes out of physics , you never know. Thinking of elegant proofs , elegant relations and that, do you know anyone who could give a talk on what I consider the most beautifu lrelation, e to the i Pi +1 = 0 ? The one that uses all those fundamental constants. I can find someone to give a talk on that beatiful relation. Someone who can relate the element of beauty to it, the compactness, the tidyness? That would be interesting. Explaining i is interesting, e to anything is interesting , e to the i something is interesting , its a challenge. Was it a monk who spent most of his life determining the value of Pi to some large number of places but after a few years he made a mistake and because it is a summation he wasted the rest of his life? They use calculations of ddigits of Pi to clock computer chip speeds because they have standard ways of doing it , how long to get a billiuon digits . Going back to the history of maths. When did most of modern mathematical X,Y,Zs ans sines and coses etc come about.? Most of the notation we use goes back to Euler late 1700s early 1800s. Some goes to Gauss around the same time. A lot of the formalisation of how we do things was the first part of the 19 century. Go back far enough everyone was doing things as word problems, not writing a + or = anywhere. So the Greeks did not have any symbols , did it all with words. Its hard for us with a lifetime of using symbolic way of doing things, to treat everything as a paragraph. So late 1700s and early 1800s most of the notations. Just sine as a function , put in a number and you get out a number, that was that time. Its surprising that it ever got started , with the Greeks thinking terminologically in words, the Romans with their horrendous arithmetic , the arabs got it going but came to a grinding halt . ? Archimedes who was Greek, sometime BC, they speculated that if he had had modern symbols , he would have invented calculus . Because basically he had every other idea except for one, but no good way of righting it down. They keep finding palimpsests of Archimedian manuscripts that had been scrapped and re=written with something else and we now have the rtechnology to read what is under the current document , and he knew a lot more than what we previously knew he knew. So he is probably the greatest M who ever lived. That is just from knowing now of what he did , and then all the stuff that must have been lost , better than Newton, Gauss or anyone else. You said that some of these problems may not have a solution , how do you go about trying to convince someone to give you money to try and find one .? Typically they only give you money if you do. You have to construct an argument which demonstrates beyond a reasonable doubt that therre are none in order to collect. So for say to prove Beals C , you have 2 choices, 1 , you write down a counter example which we can easily check 2, an argument that is sufficiently robust that you can publish it in a better M publication , given the status of the problem, that persuades a sceptical audience that your argument is correct. There must be people working on these problems every day , presumably they are paid professional Ms? We spend a lot of time teaching undergrads, sitting on committees and we still have to publish. Gone are the days where a M can sit in his attic for 7 years , do nothing else but work on 1 question and then one paper be the result of 7 years. Once its proved , does that change anything? It depends, eg the 4 colour theorem thdre is no really new idea. We reduce it to a number of cases for a computer to check but no new mathematical idea. Others like Wiles proof via the STVC , and the techniques introduced to prove it , gave us a new set of tools to then attack the next set of questions in that area. Often its not the proof that matters , but these new tools . If we think of math as a toolbox , ways of doing things , the really good Ms not only solve the questions we are interested in , they give us new tools that we can use on other questions. So the ideas in the proof , more than the result that is important. That is the joy for people like me. Show your workings please Thats right and make sure you cite whoever you use. What is the state of research into whether such problems are solveable? We know there is no algorythm for deciding Diophantine problems in general , we may be able to show there are algorythms to solve particualr cases or classes of problems. But unsolvability results tend to be rare. People speculate , after generations have passed , it is possible to prove it is undecidable. Cannoot prove it one way or another, but tht is very rare. Usually its just that we haven't figured out a way to prove it yet. Can you explain to me why it is math for yankees and maths for limees ? Not a clue . I've not the feintest of ideas. When we abbreviate we just remove the whole end of the word rather than almost all of it and leave this s hanging there for no reason and bring it back in and awkwardly glue it back on You mentioned 60 as being a wonderful number. There seems to be a number of things in maths were something wonderful falls out like that and eveyone accepts it . As an engineer I go why is that? Some of thosae interesting results in maths come from people puzzling over why did this thing show up , why is 60 turning up , why is Pi in so many things. those questions are very hard difficult to get a handle on . Hard to frame a clear mathematical question . Why does 60 turn up everywhere is not really a mathematical question. What is the math behind that question. Sometmes people ponder that sort of question and get to something interesting , showing why this thing turned up rather than anything else. We have numbers like Pi and e , are there any othe rnumbers like that ? The golden mean , Euler's constant which is harder to define but shows up in weird places . There are lots and lots of less well known math constants that do just show up in weird places. What is interesting is you get a constant, define it ove rhere and it shows up over there and you ask yourself, are these two things connected or is it just a coincidence. If ythey are connected what is the connecttion . Agaiu a hard question to answer because maybe it is just a coincidence. Or maybe what you are seing is 2 completely different pictures of some common process that underlies both of these things that look unrelated . Those are exciting things to bring together , the 2 unrelated things are actually the same. Thats what makes people go ooh!. We have to work with our target audience.

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Plain text only (see below)

Please make emails plain text only , no more than 5KByte or 500 words. Anyone sending larger texts or attachments such as digital signatures, pictures etc will have them automatically deleted on the server. I will be totally unaware of this, all your email will be deleted - sorry, again blame the spammers. If you suspect problems emailing me then please try using my fastmail or my account. If this email address fails then replace with or replace with part of the address and remove the 9 (fsnet one as a last resort, as only checked weekly)
keyword for searchengines , scicafshadow, scicafsoton, Southampton Science Café, Café Scientifique, scicaf, scicaf1, scicaf2 , free talks, open talks, free lectures, open lectures , , , , , , , , , , , , , , , , , , , , , , , , , , , keyword for searchengines , scicafshadow, scicafsoton, Southampton Science Café, Café Scientifique, scicaf, scicaf1, scicaf2 , free talks, open talks, free lectures, open lectures , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,