Well thank you for the very generous introduction this lecture is I actually gave something similar to this in Shanghai a few years ago and for the purpose of the Shanghai audience I had some Chinese characters and I thought that. Well first of all so you probably don't Chinese characters so why should I take a vowel. And secondly so you don't know Chinese characters and I want to remind you that. Science is a cultural force is global and international So either you know these characters and you can enjoy them or you don't know them and I hope you enjoy them also. But anyway I want to explain a story which is new but old and it is deep. So. I want to give an example of the history of mathematics and its uses. So main ideas. This is really the centerpiece of what I want to discuss. Because otherwise we have examples and sort of gee whiz Isn't it nice. We did this we did that but I tried to stand back a little bit and say how is it. How is it that we did this and this and this and this and this and why does it actually happen. And so there are some organizing principles or sort of a rash and now. At least that's you know my effort to be a historian or something. Whatever. So you can take that as you wish but I think that the that will be the centerpiece of this talk is the ideas of linked together and show you where these examples. Come about. So first of all I want to make the point is that there's nothing very new about mathematics having applications and just to make that point I go back to Archimedes so that you know far enough back but Isaac Newton on. So now what did Isaac Newton teach us. A teaches us that the laws of physics are written as mathematical equations and he is better at calculus in order to do that and that's new mathematics to write down the laws of physics and of course have been new laws of physics and new things. Since then but basically that was a watershed. From that point forward. Any problem that was properly understood in physics was understood by means of a mathematical equation. Now questions and solutions are quite a different story. And we struggle along for several centuries doing what we could basically the linear things somehow could be done one way or another and the nonlinear things were hopeless. John von Neumann who is also noted for foundations of quantum mechanics. But I want to emphasize here is role in the development of the computer and of computational science and his deep contribution to this collection of problems is that he can solve non-linear equations of physics the nonlinear equations can be solved effectively Here's an effective method for solving even the nonlinear equations. So. Newton says we have equations one Norman says we can solve nonlinear equations. Now you might think that that was the end of it and after nine hundred sixty and so on. It was all ancient history. Well that isn't quite the case. So he wrote a story in one thousand nine hundred sixty about. Can you imagine people are still doing weather forecasting while the old fashioned method like looking out the window and saying whether it's cloudy words you could do it all on computers and there's a long way from ninety six you today. But we still have. Observation is still as vital a part of weather forecasting as computer simulation. And. Even today climate forecasts are limited in their ability to use computers. So this is an evolving. Revolution which is taking so for half a century and isn't finished. And I have more to say about that. Why is it that he was so wrong. He would both profoundly right. But also profoundly wrong and being a little but personally I will tell you why he was wrong and he was profoundly wrong because the computers can handle basically one like scale and maybe if you're lucky one and a half just if you know it just marginally on the next one cannot handle mall the scale problems. And many of the problems are not only non-linear but there are multi scale. So I have more to say on that tomorrow but. There is there is a there is work for us even after a Von Neumann when he didn't finish everything. So let me continue with some overall ideas. So. The first thing is that the applications are not narrow they're not specifically physics. Physics engineering climate and weather forecasting geology chemistry. And those are sort of the line of work of solving the partial differential equations that define physics based problems in science or science and engineering but there's another set of ideas involving geometry and symmetry. Crystallography and Stein and general relativity. Who he started with some equations and he said Well that should be invariant under coordinate transformation and that's a symmetry principle and out of that principle came general relativity. So he derived by pure. Thought. The equations in general relativity now usually equations in physics a long slog with a lot of data and all that and general relativity there isn't a lot of data so it had to be done by pure thought. And that was basically mathematics although I think everyone would say he was a physicist but we might as well claim him as a mathematician. The same story with regard to young males and gauge theory. Discovered independently by Yang who didn't realize that the mathematician had already done all this stuff and that was also a matter of exercises symmetry giving rise to the derivation the biological sciences. Have a huge number of scales and you can go anywhere from population dynamics and the epidemiology of say the AIDS epidemic it's a very macro scale down to the molecules the HIV virus and the individual atoms that make that viruses do what it does and everything in between chemical pathways and fluids and electrical signals and so on and then there's management science and we have economics and we have finance but beyond that we have in fact Georgia Tech is a center for operations research. So this is one of your one of the stars in your firmament is. Decision making optimization and so on planning schedules. They are aligned breeze diet and live and die on their ability to have good schedules and when something goes wrong like this under storm and they have to risk Rampal all the schedules. Somehow get you there with minimum hassle. And so they re re re optimize there's a perfect schedule. There was perfect at eight am in the morning but it's not perfect by three in the afternoon. Computer science says. A huge number of mathematical issues which are quite distinct from the ones about network security and things like that linguistics. There is a large government agency that deals with mathematics and linguistics I don't know what his name is that has no such name in fact. And sociology which is maybe the newer treatment to this list with but people do highway traffic patterns and decide what is a disruption due to putting in say a repair at certain times of day you close down the traffic and what will the consequences be. And there is agent based models that do that you can have mathematical theories of voting behavior there is something called the mark of process for the. For those mathematicians among you for those who are not mathematicians it's a law of probability whereby if you did something rather today how likely are you to do something either the same or different tomorrow. And so you can do not only the voting with the opinion. But as to who you're going to vote for today but if you look at the rate of change you can say well somebody is moving up or moving down and you have so many days the election and so. Try to make a prediction with some time variable in addition to the. Instantaneous statistics. And so on social networks which have gotten a lot of prominence recently that's of interest to add to advertisers. Also interest to people who are concerned with terrorists. So there's many many of these applications. So in one nine hundred sixty. Eugene Whitner wrote a paper which is probably the most famous for its title I'm not sure how many people read the paper but the title has been very widely quoted and I think it says it all. So I give you the title there and you can go back and look at the paper if you want to but. Whitner was certainly possible but why this all happens. So what is the Edel actual force that is driving these events. So I already went through an outline form there are equations and with computers even non-linear equations you can not always but often solve them as symmetries. And then there is this business of models that transcend scales. Combining the large in the small That's I would say. As much for the future is that as the present that one. Pattern recognition and the meeting hidden in data. So these are some of the intellectual forces. And one of the technological forces. Well the computing power to solve the equations has been one of the great achievements of. The last century and probably will be for the next the. At least the first half of the century also. But it isn't to solving the equations. The same technology is used in data acquisition. So you have sensors and automated data collection so people say that for every. Computational grid cell in the weather forecasting or climate. Calculation. There is there is one data measurement. There's about as many data measurements as you have grid cells so you have grid cells. Roughly in the order of a thousand cubes. For your large calculation so that's a thousand million a billion you have a billion data cells and so the. The assertion which I can't independently verify but people claim that there's also a billion. Units of data acquisition. So there's a huge explosion of data acquisition all over the place. And then you need mathematical methods both for solving the equations and for the data analysis and for the integration of the two. And you need to understand it all and those are basically mathematical theories sometimes not done by a professional mathematician in the sense that they may get their paycheck by working in some other department where we know they're mathematicians anyway. So what are the technological forces now there's something called Moore's Law. And I think more is a very lucky fellow because he stated a rather. Circumspect version of this law but it turns out that it was so powerful that people called Moore's Law anything that looks at all like it. And so he gets credit for something that goes way beyond what he originally claimed. But that's fine that's. You know we sometimes I think a lot. It's fair to have luck in life so I don't I don't I don't argue with that interpretation. And I will take the strong view of Moore's Law. And that strong view says that the computer power doubles every one point two years. And that's about roughly two thousand and eight when I gave this talk in Shanghai but now it's two thousand and ten. So that's fifty years fifty years of doubling. So. Two point four So more than a factor of forty. Now I would say that there is absolutely nothing in the history of civilization that has doubled in its power by a factor of two to the fortieth power. Is not a factor of forty. I'm not talking about forty times I'm talking about two to the power forty every one point two years you double. That is just an unprecedented event. In the history of civilization. And I think we all sort of recognize even the nontechnical among us that something's going on out there that we don't quite understand but there's some force that's driving driving change in this world that we don't know quite where it's coming from. And this isn't the only thing but this is right at the heart of everything else that happens. And the data acquisition has on a similar trajectory and it's in fact very similar hardware because there's a lot of silicon in the. In the in the sensors. And then as mathematicians we like to remember that the methods are making all this work has also moved forward just about as fast and so the methodology for using these these tools progresses you also and so all in all this is something that. I think has no parallel and civilization in the history of civilization. It is a unique event in the history of civilization. So if you think about something like the Iron age. And that was certainly very profound when you move from Stone the iron from stone to copper to iron. And you look at the timeline for the Iron Age and it probably came in over. I don't know what a couple centuries or something like that it didn't. Double every year one point two years. Now maybe if you believe in going from walking on foot to taking a space shuttle. There is a big factor there and that that might be roughly in that ballpark. But. It just basically it doesn't happen so word. I want to put this in a context and let's pretend that you're Charles Darwin and you're on the big hole and so you write down all this former you know jihad today I saw this little flower and it looked like this and tomorrow I saw this little bug going to look like that and. So the. The descriptive stage of human understanding and botany for years was. A little but in a Project Argus sense was considered to be a descriptive science that's really not true today. But he wasn't satisfied with that. And he wanted to organize his description. And so out came the origin of the species. One of the most profound pieces of science in that era. And in which he explained all of the descriptive things that he saw in terms of certain patterns of evolution and that is what I would call a qualitative understanding. Now and then we will. Fast forward and people write down a creation for the. Way in which the genome when it does different things. When it combines it not only has Point insertions but you have whole the whole lump of genome gets disconnected and reconnected over there and so you can do rather large jumps as well as small ones. And so there are mathematical formulas that tell you what is the probability for such an event to happen. Now then you take something that very practical and this is an engineering college so you forgive me for being practical I assume and look at the HIV virus and that is known to evolve very rapidly and that's why. Treatments are not so good because you have a good treatment and then the virus evolves and goes around your treatment and goes forward and infects people anyway. So a little bit later on about the. Methods for understanding the virus in terms of finding out where it is points of high rates of you Taishan where it has points of low rates of mutation and numerical methods for targeting drugs that will block. Versions of the virus with lower rates of mutation. So those are numerical and algorithmic advances which then all of it lead lead to you would say engineering success. So this is the progressive stages of human understanding and this happens not just for our G. and not just for AIDS It happens across the whole spectrum of human experience. And so it is really transforming our life practically everywhere we look. So you might have if you were my age. You might remember being taught and driving learning driving to pump your brakes. So you don't skid but the younger people probably never got that lesson. Why don't you get that lesson because there's something smart put into your break it's called an add a lock for a mechanism and it does it automatically for you. And it was first put in these large tractor trailers but eventually got down to ordinary automobiles and I believe that's probably why you never got that piece in your education about pumping your brakes if you don't have to. So the forces that are driving these changes or advances in hardware and as I say that's unprecedented advances in the algorithms the software the use of the hardware equally important and Moore's Law Well I already went over this and this is the one of the main points no technology in human history. In my belief has ever achieved anything near like this rate of progress over such a period of time. So here's the proof. And this is starts in two thousand and eight but if I had two more years of data that would look just the same. And the. These are the top five hundred computers and the top line is the total of the top five hundred and the bottom is the bottom of the top five hundred. And the middle line which is a little more drag it is the individual computer which it has received the fastest performance for that particular year so it's the one computer top five hundred and you can see that's a little bit and the reason is giant it is very important. And that is that progress is sort of level and people say well Moore's Law is dead. So. Here you can if you go back and look in the literature at this point I'll say Moore's Law is dead computing is at the end. We've had it. We've had a road block a stone wall and that's the end of it and what happens when it hits a stone wall is that something new comes up a new a new technology or disruptive technology and jumps up again and then it hits a stone wall and so on and to stonewall for quite a while. So that's a little the top computer is a little noisier but all in all. That's a story Moore's law is very. It's still still alive in spite of periodically being. We've been informed that it had a. Hit a brick wall. So here's The New York blew it. Brookhaven jointly by Brookhaven a story broken wide a lot of the work of present tomorrow will have been done on this computer. So what are the human forces that are driving these events. Well first of all any time you do something. Well sure enough people come back and say What have you done for us recently. You know that's yesterday Now how about tomorrow and then but in addition there's a whole new set of issues that are coming up. So we used to think we're pretty good if we got the answer. Well now that people actually want to build. I can use it. The answer isn't good enough. You need the answer was an error or so are there any experimentalist in the audience. Maybe not but if there are there. You certainly know what an error war is probably everybody knows what an error war is it's an error of ours is a noose that you voluntarily put put around your neck. And then you wait three years and see what happens. That's what an air of war is so you can go at this was a little bit of caution. And once you decide what the error bar is in this is an enduring University. You need safety margins that if you're going to find designed something on the computer and you don't even have a mock up or anything. You still need safety margin so you need a computational basis for engineering safety margins that cetera and for instance take the same thing and apply it to the automobile industry. And the auto billings are used to that four or five years between models and they always got creamed because they did take them four or five years to build those model every two years people wanted a different car. And they're always going to cream. But they went on the computer and it wasn't just that they could do it with fewer engineers. It wasn't just that they could build a better car but they could build it in a bad eighteen months they could get the car onto the showroom floor. And that way they could get it while build it while people still want the car they were building. So it was a huge advantage and the companies they couldn't make it are just not with us anymore. And this happens across all kinds of technologies. So every technology is investing in this kind of transformation because they can do something better than their competitors or else they fear their competitors will do something better than them. But one way or the other this just is has a life of its own. So this is not the conclusion of the talk but it's a conclusion of the. The Ideas section of the talk. So mathematics. Is not the only force here but it is has a strong. Role in this larger enterprise and it is aiding in human understanding it is vital central mainstream and growing. So that's good news for mathematics lots of other people win too we are not unique and in fact we succeed by cooperating and collaborating. So as we win a lot of other people when also. So now I want to give some examples. And I will take them from biology engineering and physics and management science and these are basically pretty much examples taken from my own experience so they have a strong. Stony Brook centric. Flavor to them but I'm not. There's nothing special these things exist all over the world they must exist in Georgia Tech and they exist everywhere else but I'll just give examples that I know about personally so that's the basis for the selection. Now the first example was done by Sony Sonic and she did this actually in the universe if used and but she was a student of ours at Stony Brook So I feel that it's OK to include her within this and she did a study in the blood vessels. And. I will give you a discussion of how you how she improved the design of a stent which is something you insert into a weakened blood vessel we can block the vessels called an Ism and if you're an Is if it bursts. The chances are you're going to be dead in about ten minutes so if you're not in a hospital. Chances are you're going to be done. So a naturism isn't a small issue. And so people put in stents where they disc discover an aneurism it's a kind of. Liner like a little plastic thing that. Strengthens the blood vessel where it was weak and so it gives it a normal. And sort of bulging out of this on a resume. And that will do some drug design. So the question is how to repair weaken blood vessels so this was being done all along and. Sunny sonic worked in direct collaboration with doctors and medical school. She would never have done this without without them. And I believe they I'm sure they would not have done this without her. So it was a very good collaboration. So the bad old stance and the good new stance or what I want to describe. And the battle stance. Were a piece of plastic constant strength and it just ended and where it ended there was a discontinuity because you strengthened it and then you stop the strengthening and so you have a normal blood vessels so a stress at the end of the stent and that led to a lot of wear and tear and damage to the blood vessel and loss of strength and eventually the stent stopped working. And furthermore they had the branching ratios wrong. I don't know how they did that I think you do and they could have done that correctly but you have a certain diameter tube and it splits. So common sense says that the diameter of the two tubes it splits into should total the diameter of the one going in. I mean that's sort of you know I don't think you have to be a engineer or Hydra dam assess the figure that out. If you have a pipe and you have a big pipe and it splits into two little pipes you want the total diameter of the two little pipes to equal the diameter of the big pipe. But yes. The area. In fact you probably want a little more than thank you for correcting me you want the area to be the same roughly speaking but there's probably more drag on the little ones in the big so maybe the area should be slightly bigger than double. So on. The way that's what she dealt with and these are some pictures that. Part of she was kind enough to share her presentations with me and these are pictures from from her. I won't go through a lot of detail but I think I've explained the ideas. And so what this involved was first of all experimental measurements of the stand and its mechanical properties both the bad one and when they replace and got a new once they could measure the new one. Then they did mathematical modeling of that and to see what was going on and computer simulations and they came up with a new stat and then they had to put it in I hope they put in a peg or something like that to begin with but they put it in something and it worked. And so now it be has become actually standard for this is now the standard step for for repair of a of an aneurism. So this is has to do with the ratios splitting and. So those are the two main ideas and. I'll go on now to a problem in drug design. And so this is the first stage in drug design you start with a library of possible chemicals and you see if they do anything. And so normally you have this warehouse full of rats and some kind of automated thing that will put different things in their feed and you look and see what happens to the rats and it's a sort of an ugly way to do science but that. That's the that's the old fashioned method and still. Still quite a lot of that around. But this is the computer based so you have these computer things that are replacing the rats at least for a portion of the step. It is not correct that you can replace rats or animals in. Medical Discovery but you can reduce their use and the point of this. Is that you can cut years. In years off the development time and cut way down on the budget. You can explore a larger search space. So I don't think they ever do these million libraries with rats I think they have a much smaller number of trial chemicals. And the idea is just to try all these chemicals and see which one binds you have a an idea where you want to bind on the HIV virus. If you bind there or you disrupt the virus and it doesn't reproduce and so it's a good thing to do and. Let's see how my doing on time when I start. Twenty minutes OK good. So you it's a Sest the binding energies of the lake and on to this part of the wire. If you're trying to get it to disrupt and you can take a million or whatever number you can afford with your computation which is surely a much bigger amount than you would afford if you're doing it with experimental. And typically drug discoveries ten to fifteen years in the initial stages then can be replaced by computational modeling we are plying this at Stony Brook to H. I.V. and also to. Flu. And in addition you can target drug resistance by finding. Target portions of the virus which are evolving more slowly so that there are drugs that are blind zero have a bigger be more had less drug resistance buildup. So this is just some schematics of the. Of this thing this red thing is a leg and then it sticks into the green thing. And you can see the way it's the picture suggests that it was really happy to be in there so that gives you a good binding energy and so that would be a good link in the family according to the qualitative picture. They're the suggested picture. And at the bottom on the right there is an actual picture of the of the simulations with a lake and then there. So the search. Has sort of hierarchical and you start with a large number and you have to have a very approximate energy function. And you get rid of all the stuff that doesn't do very well. And you get things that work more or less and then you have a more accurate energy function you redo a more accurate calculation you could do this hierarchically. And. Then you need to decide where you set your threshold which which. Which chemicals you throw out which ones you keep and so there's a probability involved there because there's a type one type two errors you can keep too many bad things or you can throw out of the small number of good things and never find the answer. So you have can make a probability a model that tells you how to get through all of that. And I think I will skip over the I have a section on fruit flies. I will skip over most of that but I want to show you one. This is a gene network for regulation of genes and a fruit fly skipping over most of this. With a lot of mathematical equations and some green went between equations in the data so that's nice. And with this explained something called canalization. Me coming from the word can now. The idea is that. In evolution or in rather than in not in evolution but in. Morphogenesis in the in the maturing of an immature organizations. You have a lot of errors and many of the errors are corrected. So you have sort of. The genetic code you might say is this. Correct in code. So you have a lot of things that go wrong but they don't go wrong. Seriously. And then you end up end up in the right story ending spot no matter that you didn't start in the right. Perfect starting spot and it's called channelization. And it's a well accepted principle in biology in the biology. I would say the foggiest idea of where it came from. So here is some more pictures now I want to emphasize the lower right hand corner. Which is a set of trajectories of the solution of these differential equations. And you can see that purple trajectory or and you can see the blue the green trajectories the green trajectories and the point is that you can start out wherever you want and the solution of these equations flows up to a fixed point. Now that's a very simple principle and I think that probably most of the graduate school students. Might have learned that within one or two years of your graduate studies so differential equations. Sometimes have fixed points and if they have a fixed point that means that point as a solution the equation doesn't change in time. But furthermore it could and often does have a neighborhood. And in that neighborhood things flow into the fixed point. So there's a loss of information. Sometimes they just go around in circles. You know like the solar system. It just goes around in circles and it doesn't get anywhere but sometimes if there's a little dissipation in the system things sort of wind downhill and they fall into the fixed point. And the fixed point then is an attractor and it tracks. A big area of the initial condition there is a call this the domain of attraction as a technical term. If you're in the. Domain of attraction of the fixed point. You're going to end up with a fixed point no matter what a very simple mathematical principle. And that principle connected through these equations that. My colleague John Ryan it's discovered and validated against experiment through those equations. If you start at of sort of a random location of it's not too bad you're going to end up at the same spot and that's canalization So he explained. A biological principle. Why a mathematical fact and the mathematical fact is so simple that I believe. Probably most of the graduate students in this room understand. Understand that idea. So anyway that was I think a big triumph in that work and he's continuing with that. And now I'm going to get into physics and engineering applications and. Use comparable processing I think I will skip over that set of issues this is a schematic of how you make a parallel computer how you make a modern computer it has many Basically many pieces together with a switch and they all do a little piece of a big problem and this. This is supposed to explain that. But I'm not going to go into details but here is just an example of a design of a high energy accelerator and you deposited a huge amount of energy in the center of a tube of mercury and it sort of flying apart and you can see that thing in the center looks worse flying apart. And this is part of the design process for building a new high energy accelerators So that is an example of sort of an engineering or applied physics calculation using fluid dynamics. And we are also involved in the nuclear fusion there's an eater tokamak experiment being conducted in France. It's an international thing with the U.S. supplying the computation. And so my colleague Roman Samuel yok has been involved in the fueling of this. The fueling is by deuterium power to tear him as heavy water or as sea hide its heavy hydrogen that would then if it had oxygen would be heavy water so they do. Terry must have a high view that has has double the number of nuclei as a regular hydrogen and it is very reactive from the point of view a fusion. So you can get a lot of energy by combining deuterium. Into Turkey and I don't know what you get you probably get helium or something. So they have these do Terry in college so they put it into this very hot plasma and. So the idea is to figure out where that pellets going to end up and shoot it out of a gun and if it doesn't get very far. It won't get heated up and won't do anything and if it goes too far. It hits the other wall and it doesn't do anything so you want to get sort of right in the middle of the hot plasma and. Very complicated physics I'm not going to go into that but this involves a lot of simulation. And this is some of the details which I'm not going into over this is I'm just trying to convince you that there was a lot going on in this prediction. So many issues involving computation modeling physics mathematics and so on. And then something I'm working on myself is a design of a scramjet a scramjet is a mock seven aircraft is experimental it's been flown about three times and. It's a little bit mysterious how you aren't sure you're not going to carry passengers when they get through having a work. I wouldn't really want to be one of them. But anyway it flies up and it runs for a little bit and then crashes and our job was not to design it was already designed but we're working for the Department of Energy and they were curious how you can do error margins for calculation. So we're doing the error margins for this. Calculation and it has a way of stopping it. They called on START. I don't know why they call it and start when they should call it stop with anyway that's the terminology. So I'm starts and it doesn't start because it burns too much and it pushes everything upstream instead of going downstream and trucks off the oxygen and so on. So anyway we're trying to model the top is an experiment and the bottom is a simulation. And we were sort of happy about that we didn't put in any combustion yet where if the bottom of the top has compression so it. It's not an A B. comparison but it looked pretty reasonable and here is the simulation that we did and this is still without the combustion. And this is we will use them to study the on start phenomenon and this is a matter of trying to understand the calculations so we change the grid and we change the some of the turbulence models we change the new Basically the algorithm and so on. We get different answers. And the final step is to get our engineering safety margins and that is the project of the whole team not just of what I'm doing. So that's an ongoing effort. And this is the schematic of the picture the orange stuff is words burning the burning hydrogen is the fuel. Has a lot of shock waves bouncing back and forth in fairly complicated flow. So I think I went through this. I want to. So the. Quantified margins of uncertainty this is the safety margin you have to take the distance the distance is the distance to the bad stuff. If you're in a good spot and you want to make sure you're in a good spot you're not sure you take the distance for the bad stuff and you said practice off the uncertainties and that's for sure. For sure. Honest. You know put up your hand in the distance you have your safety margin but that has units and you want to be sort of dimensional So you divide by the uncertainty and that's a measure of of your safety margin and then depending how important it is you want to say positive or you want to be one hundred ten or something. Whatever your management decision what they need for a safety margin. And then I would say a little bit about the electric power grid is something we're getting into now I guess everybody is. So we're studying resource requirements. How many units are needed to meet expected demand. If you have solar panels or when there's a lot of randomness in the electricity. So we need a random source term and then you do a simulation basically that's the Monte Carlo It means you're doing something random like the Monte Carlo gambling the Monte Carlo is a famous gambling center. And this is the same thing you do a lot of trials and see what happens. So that's how we're doing a simulation. And this is a map of all the different generating units in New York City New York State. Something we're targeting We have several different aspects of this smart grid business. And then we have just for fun some logos from our simulation package. So this is to remind you that the talk is now over. And I will just say thank you. So. Just seems like you feel that the truck was given in China. And I found a Chinese mathematician and I would have to go back and look at the name right because it doesn't stick in my mind that's a very good question. In fact I had to stretch to do that. It's hard to write all the Chinese Europe with that was I couldn't find someone I couldn't find a familiar name familiar in the West and the ancient Chinese mathematics as well yes I think we're all right so well it's not entirely true because the general relativity the general to the lot of the young males was dissipated by the mathematicians about maybe twenty years before the physicists discovered it. So in fact it goes back and forth I think crystallography is I'm not sure of the first quarter crystallographer as were were physicists are mathematicians but certainly the a lot of that was curiosity driven research. So if I gave that impression. I want to correct it and I thank you for giving me the chance to do that it was a pretty.