Roger Penrose and Hannah Fry

[Music] well good evening ladies and gentlemen and welcome to the Science Museum I'm Roger Highfield I'm one of the directors of the Museum and we're thrilled to host this event for the University of Oxford's mathematical Institute it's a huge honor to welcome Sir Roger Penrose emeritus rouse ball professor of mathematics who's used a combination of maths art and best-selling books to reveal the unity between mathematics and the physical world sir Roger will be joined by Hanna Frey associate professor in the mathematics of cities at University College London who's actually best known as a broadcaster and writer and has just released her latest book hello world a good friend of the museum Hannah's also among our latest crop of trustees in fact she's been taking selfies in front of her name for half the evening mathematics provides the fabric of modern society and it's really important to the museum and appears in all sorts of guises we've got our pattern pod aimed at younger children which is inspired in part by Sir Rogers ideas the equations of aerodynamics were crystallized by Dame Zaha Hadid into the sensuous physical forms of our mathematics gallery we're doing a citizen science experiment with Reading University which aims to improve space weather predictions and that's for our new exhibition about the Sun and of course there are lots of events like this one and mathematics shows that we've developed for hundreds of thousands of school children each year so when it comes to our future projects you'll find mathematics in an exhibition that we're developing with GCHQ in all sorts of guises in our new or our forthcoming medicine galleries such as epidemiology and in a new gallery or a forthcoming gallery science city which is going to tell the story of how London became a global scientific and technological hub and now I'd like to introduce Mike Giles professor of scientific computing in the Oxford mathematical Institute over to you Mike Thank You Roger it's a real pleasure to introduce the second Oxford mathematics London public lecture following last year's successful lecture with Andrew Wiles I would like to thank the Science Museum for generously hosting the lecture and the special thanks to xdx markets sponsors of the oxford mathematics public lecture series and XTX markets are a leading quantitative driven electronic market maker with offices in London Singapore in New York and it's a real pleasure to have so many of their team here tonight it's very important for us in Oxford mathematics to get out of Oxford and spread the word about our subject to as wide an audience as possible and our public lectures are our flagship vehicle for doing this if for future events you're not able to come in person they are all broadcast live and they're also available subsequently on our YouTube channel and so to our speakers as Roger high field says Roger Penrose needs no introduction a true mathematical polymath but is he really a mathematician or a physicist tonight we'll find out and Hanna Frey also needs no introduction all I will add to what Roger has said is that her latest TV series magic numbers is also available on iPlayer and she will be signing copies of her book after the lecture so without more ado let me please present Sir Roger Penrose [Applause] well thank you very much for that introduction I suppose you want to know the answer to the question about whether I'm mathematician or physicists one of my physicist friends keeps worrying me about that and sometimes people ask me so I think the answer to it is that mathematics I found absolutely wonderful and a huge pleasure and that's what I do but it's the physics which drives what I do so I'm interested in physics as and what what are the answers to the way the world works and that sort of thing so I say the big drives come from physics but what I actually do in detail is usually mathematics so I'm both I suppose I hope I'm both anyway anyway I want to give a little talk which is to do with things I've been doing extremely recently in fact some of these things were only just about last week or so so it's really up to date so let me explain I'm going to talk about cosmology and code so perhaps we could have the first picture no that's just that's the first picture thank you now you see this I like when my mathematics I very much like geometry or I can do bit of algebra too but geometry and I like to draw pictures of things so these are pictures of mine which I'll show you I often show them on a an overhead projector or something but this is a nice way of doing it you get nice big pictures here and this is a picture of the universe I should explain various things about it time is going up so you think of any one moment if you like of the section through this and one thing I should point out if you look right at the top you will see it's a little bit strange and there's that frilly part of the back that's because I want not to be prejudiced as to whether the universe is spatially open or closed it might goes all the way around or it might decide to do something else in the very great distance so that's really what that's for so I have the frilly bit at the back so I don't care at least from the point of this talk whether the universe is spatially open or closed now right at the bottom you have this thing called the Big Bang and that expanded out the universe expanded out from that and this expansion I should say is very much in accordance with Einstein's general theory of relativity which he introduced in whatever it was 1915 and there is this exponential expansion that you see if you go up it's it's span expands out a bit slows down a bit and then starts to do this what's called an exponential or self-similar expansion which has been observed for looking at distant supernovae stars and so on but Einsteins equations require what's called a cosmological constant it's usually called lambda these days people call it dark energy I don't like the term very much because it's neither dark nor energy in the sense it's pushes rather than pulls Rose energy in gravity pulls things in so it's a little strange the terminology never mind anyway that's the dark energy and it causes the universe to expand and expand and expand and this behavior isn't all the cosmology books if you put in this lambda they cause a lot of a constant and when it's positive that's what it does so that's pretty well a picture of the universe as we now believe it to be except people usually think right at the beginning there is something called inflation and I might be asked why haven't I put inflation into picture well there are two reasons one is maybe I have because inflation would be right tucked in at the little black spot at the bottom you wouldn't even see it in the picture this inflation was supposed to have taken part in the universe's activities in the first about ten to the minus thirty two seconds so think of one followed by thirty two zeros one over that that fraction of a second in fact is supposed to have been within the time that the inflation took place now if you want to see what inflation is supposed to look like we need a pretty good magnifying look at that little point at the bottom so let's have the next slide please and there's the magnifying glass when I use overheads I put that one on top of the previous picture but I'm not doing that here what I'm going to do is show you what you would see with this very powerful magnifying glass can I have the next picture please and well the thing at the top I should say is just the handle of a magnifying glass so that's not something funny about the universe forget about that but the you see this expansion looks very much like what we see now as this exponential expansion of the universe which is observed now from the observationally nova stars and all sorts of other things which fit together to get the picture that that's probably what the universe is doing now but this view is that within these first 10 to the minus 32 seconds it did this other exponential expansion and expanded by some huge amount in that tiny little point now I never liked this partly because it didn't fit in with Einstein's equations very happily partly because well it didn't do half the things that it was supposed to do supposed to smooth out the universe and it doesn't do that however it does do something it does a couple of things which are important in cosmology I'm not going to say much about that except that they are important and that if we don't have inflation you've got to have something a bit like it so I'll come to that shortly before that let me describe something about infinity you see the universe does this expansion and then it's going to go in spending and expanding and expanding right out to infinity at least that's what Einstein equations tell us so infinity is a nice thing to talk about in mathematics and it's very important in mathematics people say you can't really understand infinity can you well you can in mathematics that's just what you can understand so let me have the next picture now that's a very nice illustration of infinity and it's also a very nice piece of geometry I am very attracted by this picture it's an Escher picture if he was told about this geometry by coxeter who is a very distinguished mathematical geometry and he said to Asher why don't you use this representation of what's called the hyperbolic geometry so you have to imagine that these fish I think their fish are all really the same size and shape but when you get around the edge they're squashed down and the way they're squashed down is according to what's called a conformal map conformal means where small shapes are Preserve they might be bigger or smaller but they're not squashed one way or the other if they squash this cost always in the same way to the same degree so it's what's called conformal that means angles so you take the angles on the fins or the wings or whatever they are these fish and those angles are exactly the same no matter how close to the edge you are so according to the universe that these fish inhabitant if she's called as I said hyperbolic geometry well this is what's called the it's called the Poincare a disc which is of course in mathematics you often find that the name attached to something is not always the first at the right one and it's really Beltrami who was an italian geometer who thought of this representation before on Kure well Frank were a male of very important use of it so it's alright to attach his name except Beltrami got about rather bad deal out of it there's another of about romney's representations called the Klein representation again he doesn't get the credit for it but it's very beautiful and the straight lines in this geometry are really circles well you they look like circles in the picture which meet the boundary at right angles and if you follow the the fish the noses of them and they go nose to tail all the way around you'll see your circles all over the place very nice representation now the point I really want to make about this is using this conformal idea so in the geometry we don't know about distances you just know about angles you can represent often if you're lucky infinity so this boundary around the edge you can look at it and you say well you could step outside that but these fish think that that's infinity as far as they're concerned so that's the kind of representation which I had been very keen on I've played around with these conformal geometries for a long time before I started doing research in mathematics or at least official research I was supposed to be doing and my interest in general relativity I found my interest in these things were important and I learnt how you could study things asymptotic things like radiation I mean what does if you have something radiating and the radiation goes way out to infinity and to describe it if you have infinity just sitting there it's very helpful so I was playing around with these things in the 1970s and so on okay now let's think about our cosmological picture I think I want the next slide please if I've got it right see here what I've done is the same trick as we have in the Escher picture applied to the remote future so the remote future goes on and on and on and on and one of my reasons for thinking about this in this conformal way was it seemed to me that the universe well I mean it gets pretty boring for a while when black holes have swallowed pretty well everything of interest I'll come to the black holes in a minute and then as we can see that's how go to the next picture of quickly and then I'll go back again if I can do that this is a picture of again a spacetime picture so time is going up and we have some collapsing material at the bottom and then we have the black hole you need a few more dimensions to picture it properly but the black hole is represented the horizon is where you see that line the singularities in the middle and the horizon is just outside that and then according to Stephen Hawking after a while these black holes disappear well I'm fooling with a pop because whatever kind of an explosion it is it's very very tiny on astrophysical by comparison with other kinds of Astrophysical events so this black hole it can be when you see our galaxy has a black hole which is about four million times the mass the Sun there are lots of smaller ones undoubtedly going around but the middle is extremely big and you can see it's quite amazing you can see pictures like a movie of these stars are going around this thing in the middle you can't see a thing in the middle because the black hole you can't see directly but you can see the stars going around it and this you can see in speeding it up a bit but it's quite impressive so it's there now what happens to the black hole's eventually well you see they evaporate away by Hawking evaporation and then when they've all gone how long does that take well for the really big ones you have to think of something like a google yes what's a Google well that's one followed by a hundred zeros not a very scientific term perhaps it was invented by the nephew of I think a mathematician and it's a nice name to say if you mean a really big number now Google if I say ten to the hundred years and that's the saddest time you're going to have to wait before all the black holes have gone the really big ones take the longest to go away and the smaller ones go in much more quickly but after they've all gone now thought it was pretty boring before sitting around watching for a black hole to evaporate away though that's dead boring when they're all gone that's very boring but then I began to think who's going to be bored by this well photons probably mainly photons and it's really hard to bore a photon it's hard probably for two reasons ones it probably doesn't experience anything but the other is from relativity effects photons if I could say experience don't experience time at all the time from creation of that photon or whatever happens to it is nothing to that photon so that it goes right out to infinity and it's as though this has just happened instantly so as far as the photons or other particles which have no mass are concerned infinity is right there so I'm going to show you in the next picture next one please no that's is that the next one I can't remember perhaps it was the next one little do these are the cones that you pet saw in the previous picture they're very important they're what I call light cones on now cones and they represent what light would do so think of the big picture at the bottom and here I've got a couple of clocks the histories of those clocks and they're supposed to be identical clocks and these perform whenever they are bowl shaped surfaces represent the first tick the second take the third tick but the light cone is there irrespective of the clocks and it's very important they're sort of sitting there at any point in space-time the main structure of that space-time is given by those cones it tells you what light would do if there were light there and you see the photon zipping along like that with the speed of light that means going along with its world line going along the cones and you can see if you look back at the previous picture with the black hole that the right on the horizon the cones are all tipped over so that the light rays are along the horizon but anyway I want to show you these pick this picture here because it illustrates something important about relativity the thing I want to illustrate is that you guys think all the metric now that defines the structure of space-time at every point there's what's called the metric now the metric is a thing which has ten numbers to describe it nine of those numbers really it's the ratio of the ten numbers nine of those numbers and that in that sense tell you where that light cone is so that's most of the information the one other bit of information are the ticking of the clocks now in relativity nowadays we have extremely good clocks very very very precise clocks they're so good for example but one of the effects that Einstein predicted about clocks is that if you had a clock down here and a clock way up there the clock down here would run just a little bit more slowly than one up there but nowadays if you had a clock sitting here and the clock ticking there we can now it measure the difference between the time rates very very precise now the fact that we have such precise measurements of time is one of the things that underlie is the very precision of Einstein's general relativity now the one important reason for that is the two formulae that I have at the top on the left-hand side these are the two most important formula of 20th century physics one of them of course is Einsteins e equals mc-squared which tells you roughly speaking that energy and mass are equivalent okay but C squared but that's just a constant energy and mass equivalent the other formula is max Planck's e equals H nu I think people call it F often these days that's the frequency he is again the energy and Planck tells us that energy and frequency are equivalent okay you've got another constant which is Planck's constant but that's a constant so we have these two formulae both telling you energy is something and one tells you it's equal to mass the other tells something even to frequency apart from constants so that tells you that mass and frequency are equivalent so if you have a stable massive particle that possible is a clock it's a clock of incredible precision it's not something that you could necessarily measure you couldn't use it on your wrist or something you have to have some way of scaling it down so you extremely high frequency but that's what these essentially these very very good clocks depend upon is this fundamental fact that energy and frequency are equivalent in physics now suppose you have no mass photons don't have mass they aren't any good at being clocks and they zip along the cone they never hit the first of these bowl shaped surfaces so that the first tick never happens those clocks don't experience time at all so suppose you had a situation in the universe where where there weren't any massive things around then it's really the geometry of the cones that you're interested in and that is in relativity in space-time structure the conformal structure I see angles that's the conformal structure well here it's the light cones and that's the same thing so if you only have the if you don't have any mass you've just got things without mass then they're not really interested in the metric they're only interested in the conformal structure so now you can apply the trick which are just illustrated in the ashmore issue illustrated in the picture I just showed you a moment ago with this infinity of that geometry been represented by a nice boundary a nice smooth boundary that trick can be used for the whole universe now can I have the next picture I hope it's the right one I think the pictures gone missing this fisherman can we go to back to back to back another one back another one that's it yes did we have that picture I can't remember anyway you'll see the tricks here right in the remote future that's the trick I'm talking about we've squashed down infinity then become a nice smooth future boundary and as far as the photons are concerned they zip along and they get to the boundary so if you had nothing left about things without mass those are the problem about electrons and so on you need to do have a scheme which gets rid of that problem which is probably the mass phase out in there very remote future but let's not go into that issue it is important for this scheme but let's suppose you have nothing left but photons then you can do that trick what about the other trick this is the opposite trick you see we have this nasty Big Bang in the beginning how do we talk about that well again you can try trick this is the other direction where you stretch it out now here the reason you can get away with that is because things get them hotter and hotter and hotter than in you get to the Big Bang then the nearer the higher the temperature gets and when the temperature is extremely high that means each particle has an extraordinary high energy far higher than the mass energy that according to the Einstein equals MC squared is so you get an energy which means that the mass becomes completely irrelevant the closer to the BIGBANG you get the more irrelevant the mass gets and so therefore this trick makes physical sense now I should say that the future one applies very very generally there's a theorem due to Helmut Friedrich which tells you that you can get away with this very big general case of irregular universes in the other direction it's completely the opposite it's a very very strong restriction on the world that the Big Bang can be treated in this way I kept worrying for a long time because we know there is a very big restriction it goes down to thing called the second law of thermodynamics I can't spend time talking about all these things then the colleague of mine poor Todd who was a student once of mine and he had a much way of better way of describing that the very very very strong restriction that the Big Bang had to satisfy is that you can stretch it out to make it something nice and smooth so here we have a nice representation nothing outrageous with regard to cosmology you can squash down infinity stretched up the Big Bang this squash down infinity looks like the same as to stretch that Big Bang you might say isn't the Big Bang very very hot yes it was but then you stretch it out it gets colder again and you squash down infinity it gets hotter so they look pretty much the same okay now let's have the picture with that we I think the last one if you rattle along to the last month great now this is what's outrageous the one I had before okay requests many people have to agree with me it's ok but now this is outrageous our Big Bang according to what I'm saying was the conformal continuation of somebody else's infinity now I'm calling these individual things on the left eons I looked up in my dictionary to see how long an eon was and I was glad to see there was no definite length of time so I'm gonna call it the entire history of the universe is 1 Eon now our remote future then because there's nothing left with any mass becomes equivalent to a Big Bang of the next Eon and it's nicely smooth out in just the way you want to have the second or thermodynamics and all that stuff in the right form so it really works very nicely of course not only be in the cosmology community like this idea because they've been brought up with inflation and where's inflation in this picture well actually you can see it because if you take the one in the middle to be ariane then the one before and rather than having to have a big magnifying glass to see that exponential expansion you can see it in the previous eon now this is an idea which is a bit like an idea that that was italian physicist called valenciano had its model was a bit different from mine but i'm not claiming originality for that particular concept because bennett co had it in his model but okay anyway that's that's the conception I have with consort conformal cyclic cosmology and I find it rather attractive it makes nice mathematical sense so that's why I like it if you like when I'm a mathematician does it make physical sense well I gave lectures about this for many years and I was quite happy to give the lectures because I thought nobody's in a good ever going to me overdoing observation which will prove it's wrong so I'm nice and happy then I started to think it's like maybe you can find an evidence for it and the thing I thought of was the collision between supermassive black holes which would produce a huge gravitational wave signal you see we have this four million solar mass black hole in our centre we are on a collision course with the Andromeda galaxy which has one inch about 30 times bigger than ours something about there and so there will be one walloping explosion when they hit each other and swallow each other up we won't be around to see that but people may be in the EON beyond ours might see the effects now what I'm saying is that we might see this kind of thing happening in the eon prior to us well I'm not going to talk about that because this is all very controversial do we see these things I think we do but we get into all sorts of trouble me and my colleagues my Armenian colleague and my polish colleagues who seem to ok I have some decent papers on this seems to giving good evidence for that but nobody's picked up on it more recently we had another idea this is very appropriate in a way because it has to do with Stephen Hawking now I showed you that evaporation of a black hole and Stephen was very wide that his prediction of black hole evaporation was never going to be seen he hoped it would be seen with little black holes in the in the Big Bang and but nobody saw it but what I'm claiming just think about it for a minute that black hole although the radiation coming from it is very very weak extremely low frequency all that energy in that black hole is finally dumped into this photon mainly photons so that by the time of the crossover let's talk about the previously on there the one below the one in the middle think of a black hole in there it's been sitting around and right tucked up I talked about the Google yes where is the Google years in this picture is you could hardly tell it from the crossover surface to the next one it's right tucked up there but all the energy in that black hole is contained in that and where does it go well it bursts through into the next Eon now my colleagues Christoph Meisner Polish colleague and Daniel Ann who is a Korean who works in New York have been analyzing the Cosmic Microwave Background that's the radiation coming from well is it the Big Bang well it's coming from about 380,000 years after the Big Bang but still it's pretty close to the Big Bang on a cosmological scale and what we claim is happening is that the energy from the black supermassive black hole in the previous Eon burst through to that crossover surface and in the 380,000 years it spreads out to a distance which is about eight times the diameter of the moon that front of cosmological scale is actually pretty small the moon looks quite big to us but that's first I don't know from home sky is really quite small and this is the what we call Hawking points now the evidence for these things the analysis not all of which has appeared yes we have an article on the on the archive but the new one we don't have on the archive yet the confidence that one give gives to the signal by the usual tests that people use in cosmology would be one part in the wealth in about some well of heart wonder than about 50,000 now 5,000 yeah because you do a lot of tests to see whether they random skies that you construct do you see this feature so the feature is about confidence level is about 99.98% confidence so it's it's a pretty impressive thing whether anybody is going to believe it after that I'm not sure but all they have to do is look so thank you very much [Applause] absolutely fascinating so okay I sort of want to make sure that I've understood this the the cyclic cosmology yes so is the idea for our current universe then is the idea that we'll get gobbled up by black holes oh no no we don't get gone like they sit there and the universe does what I showed in the picture it goes expanding out and out and out the black holes as a whole I mean that big but they're totally from the point of view of the universe as a whole so so they're very small in the picture if I drew a black hole in I think it would just be a line going up you wouldn't see the diameter of it store so how has this gone down in in the community how have cosmologists it's that very badly from my point of view very badly yes well you see the old idea about the big collision and then gravitational waves would cause a signal which to independent groups I have a person who collaborated with waha Gossage on who's who's an armenian and he initially did a bit of analysis which people were it was bit unconventional to people but the paper we finally published on this we have a way of showing that this is not random mainly because you see this set that you should see circles in the sky and these circles are very concentrated in certain regions it's clearly not random but nobody believes it because it goes against the conventional view and then Christoph Meisner and this the first paper they had was to two poles have only off skiing and and Daniel and finally get they published the paper published in the Monthly Notices of the Royal Astronomical Society after having many many referee killing bang say look this is no good you must do this test you must do this they did them all they did absolutely everything he asked and finally the editor wrote for them to say more or less well I suppose we're going to have to accept your paper it wasn't quite in those words but it was more or less less and they say we'll accept it on condition that in the first paragraph you say this might be a chance effect but it could be a chance event like anything and they give the chance the chance is about a hundred and twenty four to one that it's a real effect nobody pays any attention I asked Chris tough what responses you have zero and so we've had zero and I sue it's not like you know all sort of angry people saying done this wrong and that's wrong on how can you do this and it sure it contradicts this deathly silence that's what we've had and now we have a thing on the arca we had a paper rejected already big from somebody complaining that this thing says this this this result is unbelievable they haven't checked to see that it's really they're just unbelievable it is unbelievable if you believe these effects come in flip from inflation because for an inflation it would have to be at the very last point of inflation otherwise you shouldn't see anything like this and that's what they call graceful exit they have a problem of getting rid of Lee how do you turn it off you see how do you turn it off everywhere all at once pretty well all at once that's a big challenge that was one of the reasons I had trouble believing it from the start so it would contradict that view so that's why they say I suppose this is unbelievable it's unbelievable on the basis of cosmology but I guess picking up on that point more generally there are there have been times in the past where there was a sort of conventional wisdom in physics that eventually has overturned do you think more generally there are other areas of physics that are currently being misconceived yeah I would say the main one is quantum mechanics now quantum mechanics people say is the most well tested theory in physics I'm not sure if that's quite true you have to compare it with general relativity the two big revolutions of 20th century physics quantum mechanics general relativity they're both extremely precisely tested with you know let's not make a comparison it's a bit different in each case extremely well tested now people normally think I I'm just guessing but they think well quantum mechanics is the physics of the small big things are made of small things therefore the physics of the small rules and therefore if you have conflict between the two areas you've got to give in to quantum mechanics that would be fine if it weren't for the fact that quantum mechanics is self inconsistent now I'm putting this in a rather strong way I mean Einstein said it's incomplete that was he was much more polite I thought I was incomplete Schrodinger agreed with him people may be familiar with the Schrodinger cat Schrodinger's cat was given by running as a demonstration of what's wrong with quantum mechanics is more or less saying look an absurd thing like this is what my as Schrodinger's equation predicts his own equation predicts that you could have a dead and alive cat which is dead alive at the same time now you never see such things and people might say well it's hard to make new coherence and environmentally correct all that kind of stuff but it never really solves the problem so where people are led correctly is that - what these rather many worlds kind of interpretation ok the cat is the dead one and the live one coexists in two separate worlds and we are there to believe that that's what quantum mechanics tell us well it is what quantum mechanics tells us if you believe that this linear Schrodinger equation evolution or unitarity as people call it is absolutely universal now when I when I had my phase of going through many words myself but I I came to the conclusion that that's probably wrong and that the unitary evolution which says these super positions of quantum mechanics says that that you can have a particle which is here and here at the same time and you get that's true um you get two slits and it seems to go through words at once very strange and they say well what's the limit to that could cricket balls me here and here at the same time well according to quantum mechanics yes but you never see that so why don't you see that well there's all sorts of thing as well as decal messed up with the decoherence and their atmosphere and all sorts of stuff but that doesn't really explain it so I never was happy with that person never that's wrong because I did have one time in my life when I believe the other thing but the thing is that when you start thinking about general relativity you realize that there is a serious conflict between these super positions that there's a problem with the very fundamental basis of general relativity which is principle of equivalence the things that for you know a big big mass and a small mass fall together Galileo whoever it was the astronaut who dropped these things on on the moon fell together people expect that fundamental principle which drove Einstein who is amazing theory is inconsistent with quantum mechanics and so I was developing that idea and that gives you a limit to when these quantum superpositions will persist and these are experiments which are being trying well some of them have been going on for several decades I would say and not yet with an answer so they've kind of borderline what you one can actually do with current technology but I guess this is something that you have done quite a number of times in your career in terms of challenging conventional understanding of various areas of physics what sort of a frame of mind do you have to have to sort of the bravery to be able to do that because in this problem I don't know it's them partly I think not worrying about what people are going to think about it which is probably most and not realizing what people are going to think and thinking okay it's all right and not realizing what people's reactions are and I can feel a little bit of happy about this quantum mechanics one because Einstein yeah but I stand in my side well he was there long time before me and Schrodinger the boy a little more surprisingly Dirac it was to find a quote from Dirac and you say yes see if you find the right quote you could see he thought the same thing quantum mechanics is a provisional theory because of problems like this and other problems ok it works beautifully brilliantly it must be pretty correct you have these experiments now which it used to be that quantum entanglements this things happening here and here really know about each other in a sense and quantum entanglements were though I think the record a few years ago was a hundred and seventy three kilometers or something now it's I don't know thousands of kilometers these experiments with satellites and so on them so quantum effects stretch over those distances I'm surely glad they do because not that's not where I think think things go wrong if they went wrong there my ideas would be wrong too you see so it's it's it's got to be mass displacement you see when you have a bit of mass doesn't have to be much a bit of mass to space and it's here and here at the same time if there's too much mass doing that then you're in trouble with junior general relativity and so that's where I think you're liable to see a difference but people say Oh what quantum mechanics so beautifully tested but they've never tested it at this level but you asked me why do I I think it's because I didn't don't necessarily I don't know I think my father was a bit like that see he he certainly had it you know he just thought what he thought and if it was against the current beliefs that was all right so you sort of jokes there about being big-headed but you're not afraid to change your mind either I mean there's been several times where you've you've you've gone against what you've said in the past the big bang thing yeah no it was it was strange because I was quite early on Stephen Sacco got I don't know he got wind of it and some when I went it was interviewed by him and he this is hard talk BBC's HARDtalk that's right absolutely and so you know it has essentially an he went to the beginning he's always talked to me quality said look it's my job to be rude about people you see usually I talk to politicians but I'm afraid I'm gonna have to be a bit rude who's that alright success of us alright by me so at one point you see you said why did you change your mind see because I used to believe the Big Bang was the beginning and I'm saying it's not the beginning I had these theorems with Stephen Hawking these theorems about singularities and they had they could say very general circumstances if you believe in science theory you've got to run in these singular state where things things go wrong so that's the beginning so well you have to have your way around that and I thought the reasons against it were I mean against it just being the beginning we're much stronger and the previous reasons I had for believing in it so yes changing your mind is past I think I said in the interview well I I think being a scientist I'm allowed to change my mind if the evidence starts to point the other way very true I mean you do have these quite bold ideas I think is fair to say I mean I think you've described them as crazy I did especially also how can you tell the difference between a good crazy idea and just a crazy idea well it's true with the CCC's I think I was a conformal psychic cosmology I call it see see see that scheme when I talked about I used to call it outrageous or crazy mainly because I did I want to get in there first because before other people started saying it's crazy but it is a crazy idea but then so is inflation you see so so ok one crazy idea against another crazy idea but there's something pretty crazy about the Big Bang and Einstein already it rises the early stages he thought it was pretty crazy already he thought that all these people who will Lemaitre I guess and and other people who'd got solve the equations Friedman and Allah made sure solved Einstein's equation so look there's this singularity the mean and I said look that's bad physics then eventually he had to be convinced that this made sense in the equation so he had to change his mind there there's also a funny thing about being the lambda lambda cosmological constant you see because as I introduced it for the wrong reason he was a university rest' attact and just expand and then give us a bubble shows universe expanding whoops so Einstein retracted and said oh it's the worst mistake he'd ever made you say that cause well it turns out to be true you see sorry I'm yeah and no I think I think it partly was my father because he he he had the same sort of attitude and he didn't mind whether things were unconventional not what other people did as long as he had good reasons for thinking what he thought so do you think you can you can teach someone to challenge the status quo you have to be careful at the same time when there's a huge amount of evidence you say I get letters from people emails these days from all sorts of people who put forward other and they think you know I'd be very sympathetic with them because I've done this sort of things you say but I would be sympathetic with their ideas which are just about as crazy as mine but the trouble is that so often they come into conflict with well-established things and so it's alright to be crazy but you've got to be careful that they're not in conflict with well-established physical facts and I think that's a lot of people don't take that part of it into into consideration a difficult line to tread though it's it's a type yeah just now and we spoke and so far about mainly the your ideas in physics badly you've had quite big impact in a number of different fields I mean computer science artificial intelligence but also in the art world so tell us if you would a little bit about your your collaboration or your work with Asia yeah well this went back to I think in my second year as a graduate student when I was at Cambridge and the International Congress of mathematicians was being held in Amsterdam and so I decided with some friends of mine we would that be fun so I went to have some here the great Herrmann right figures they're talking about mathematics and I remember seeing getting onto a bus at the point where Sean Wiley who was a lecturer in topology to me when I was Cambridge and he holding in his hand was this catalog with this very strange-looking picture you opened it up and there were these it was Ashis night and day with the birds flying one way and foot and they become birds flying the other way in one it's night and the other day and you spaces between the birds become the birds go in the other way my god what's that and he said well there's this exhibition going on and in the fan core Museum and you I'm sure you'd be interested in that so I went to see this and I was absolutely blown off my feet there's amazing pictures particularly I remember the one called relativity with the people going the staircase is pointing at right angles to each other and so on well on the other side of the stairs and so I went away and I thought can I do something a little bit different when I've seen which is impossible so I started drawing pictures of bridges and rivers and all that which went over each other in the impossible way and finally came out with this try bar which is so I think we have a picture of this thing yeah no game this is your original drawing I think is it yes I think that's the one yes yes you see I showed that to my father and he showed it to all his colleagues and there are maybe people thought they made them feel you know it's interesting when the chimpanzees apparently showing this they also feel it really apparently yes I was told about this yes it's not just humans how can you tell if it's chimpanzee he feels it I'm not sure but I was told there were experiments that showed Wow yeah that's interesting apparently they felt very uncomfortable seeing these anyway you see so there my father started drawing buildings virtually impossible and and then he produced his staircase going round and round neither of us were aware of Oskar writers fard who played with these things earlier Oh in fact people different Bridal pictures and things which use these structures in fact a she knew about some of them too but we decided we'd write an article on this which we did with the triangle in the staircase and then we thought well what journal will accept this what's what's its subject so my father said well I happened to know the editor of the British Journal of Psychology and pretty so he would take it in so we decide it was Cosmo psychology so we decided it's quite psychology in fact he they did get it accepted for british journal psychology and it's become psychology I've seen some psychology books but we sent a copy to Escher and gave credit to the issue exhibition and then my father had a correspondence with Lesha and then somewhat later I actually visited Escher and he got I had some these puzzle pieces which I left with him and he gave me one of his prints which was a great honor to get one of these from him but he eventually started including the triangle in his own work yes well he from our article the first thing you put in was the staircase and he had this one called ascending and descending we've got that as well actually going round in two directions that's right now it's an amazing picture yeah and then this one came later the war so the waterfall came a bit later yes that's based on the triangle but he in the meantime had produced Belvedere II which uses the same type of idea so that he who goes was stimulated by these things and I got stimulated by him also with sort of some of his repeating pictures and so on mm-hmm and talking of repeating pattern yeah so this isn't a one-off you're sort of you know playing around with these kind of shakes because of course many people will know about Penrose tiling well I used to fiddle around with just periodic once a lot I actually have picture as well there oh this is yes this is the I've come to version mistake okay but the I just I used to draw in my notebooks little complicated ones we said more and more complicated ways of repeating but they were repeating and so these are shapes set of shapes that you're Tyler plane with yeah and you're trying to make it so that you never repeat yourself well that came yes you see yes that came a bit later you see unfortunately it came just after asha died and my father died both of them would be very fascinated by these things was a great shame I'm in Asia I was a bit slow alpha mark I'm afraid because she would have appreciated you see I first of all I don't know patterns I think it was I was trying to answer a letter and I couldn't bring myself to but there was a logo in the corner which was Pentagon with six Pentagon's inside and I thought well suppose you repeat that several times and I thought of a row rule for doing this and I made a big picture I sent that to a friend of mine who was in hospital just to cheer her up a bit and then a little bit later I looked at this thing and I thought is there some way of forcing this picture with a jigsaw puzzle arrangement I don't know why I had that thought but I suppose that's one of these things you might say a guess or something which I was giving it about 50% chance that that was and then I tried various things I surely you could so I needed about six different shapes and with four shapes and I needed three of the Pentagon's and one of the rhombus is maneuver other shapes and and then I stood could do it with six shapes and I had a conversation with with an American mathematician Simon Cochin who was his thing in Oxford and he was talking about Rafael Robinson had six shapes which would only tell the plain non-repeating way and he said Rafael Robinson somebody likes to get down to the smallest number possible so I said well I can do it with five because I knew I had the six and I could I knew there was a way I could glue two of the pieces together and I could do in the five so I can do it five so I went home and I started thinking about it for a bit that's up there good I got it done before that's nice no I feel a bit more and I thought oh I can do it with two and I tell you my reaction to that people asked me what was my relation I tell you what their reaction was disappointment because I this is just ridiculous it's it's soot it's so simple it must be you know the Islamic designs or something must have it I mean purely surely that's not new but apparently it was new I mean nobody is founded in Islamic designs so you can see here what you have to do is to have the two shapes I hope I don't if you can see they're both rhombuses rock diamond shapes and they're slightly different there's a dark one and the light one the light one is the thin rhombus and the fat rhombus is the dark one now each one has two stainless steel arcs on it and the thing is you have to match the arcs I'm it's done with the arcs that nobody else has done this yet anywhere else as far as I know but the originally I just put little arrows on the shape so you had to match the arrows and they would be non-periodic the only way you can tile the entire plane right out to infinity is with a non-repeating pattern and each of these that one nice feature about it is if you go out to infinity and you take any finite subset of it that appears infinitely many times in all the others so this is true here and instead of putting little arrows you have to match the arcs and I like that because it brings out these circular features and nice things to look at so we have this now in the front of our building and and people might say is this a special picture well anyway of tiling with these patterns right out to infinity will have that exact pattern in front of our building infinitely many times I quite like that you came up with this idea when you looking at a stamp on a letter were you essentially procrastinating so do you make a distinction then between the sort of the math that you do when you're playing around procrastinating and the math that you do very seriously no I mean that's a good question because they you share would be doing some problem like when I was doing my PhD and beating my head against the problem which are never properly solved and I'd keep coming back to that but then you know you go say well let's fiddle around with something else which is fun you see and then I go back to that problem so I give you like that's that's the difference between progress and anything and tell me what we're supposed to be doing and maybe the procrastinating was in some ways more fruitful I don't know that's an interesting question I'm not sure the answer to that but it certainly has been fruitful yes that's true I think I think it probably was more I don't know I'd have to go back through my old notebooks and see how many were the result of procrastination and how many were but I think you see you could think along the route you see you have a clear kind of route say well that's the obvious thing follows and that's the follow us and then you say back well let's try something else it's not something it's a comfort and it comes back into the same old thing that's trying before I put tried that already how about this then it comes back again for the same whole thing so it's not often you think something which is really different and that does usually require a bit of maybe not thinking deliberately about the problem something else which suggests a connection oh that's a little bit like that oh maybe it's something like that and it may be a little bit of thinking outside the box is that's what people stay play I guess as well just sort of playing with things yeah yeah okay I'm going to come to the audience in just a second and so if you have questions that you'd like to ask some Roger then and please do you think of them but I wanted to ask you just in the last couple of minutes I have with you I just wanted to ask you about your experience of maths at school because I heard that you were moved down a class Roger I was moved down a class yes I was a I think it's when I was eight years old I miss it a little while back this was a class in in Canada a school in Canada and they teach there was one teacher who had what was called high grade high grade two and low grade three I was in low grade three and she used to have us do sort of mental arithmetic you had to add multiply things and she was too quick for I just couldn't keep so I was considered to be pretty stupid I wasn't very good at arithmetic anyway I was very slow at it it's always got lost and I don't know if it was that or not but she considers I was too stupid and she moved me down to high grade too after a few days she thought maybe it was a little easy for me to so yeah she we never got all I may say at one point there was a moment much later when a number of people not just me got moved up to high grade 3 instead I think she's just getting rid of me I think she just thought I was too stupid to be able to be dealt with so she thought she'd get rid of me by moving in means a high grade 3 instead which I found that I got on with a teacher better but then there was a tea I think was a bit later there was a teacher who I thought was pretty insightful because I didn't do all that well in the math tests but he said look I'm going to let you have as long as you like there's it was supposed to take the period and at the end of a period people had the paper census taking songs you like don't consider that's the end of the test people go out and it was the play period after that look longingly out of the window to see them playing around but I would keep going and we keep going sometimes even the period after that I was still going strong then I do well I'd get into the high 90s you see 199 100 or something on on these tests so I thought that was pretty good of him because he realized I was just too slow and it was partly because I wasn't very good at remembering things you know my times tables maybe I couldn't had to work it out each time so that was pretty slow obviously I had the idea but I didn't know how to do it quickly and this this was with me for quite a long time i speeded up a bit after the years but that was always pretty slow yes so intensive if you could have a chat with your 17 year old self then well I guess maybe more a message to people who are 17 now and kind of coming through the school system yeah but they do have to sit these timed exams and more generally what advice would you would you give me it has to be now I think rather than me then other people at that time because maybe I've ever given the same advice I'm not sure what I've asked speeding off asking me down I really don't know what advice to get people I think it's much more difficult now because of a horrendously competitive the way that schools are and schools and universities tremendously competitive and you have this horrible conflict because on the one hand you've got to be objective and how do you how are you objective will you make a test which is objective and then people you know they learn they you know you can make up things which are new and people haven't seen before but that's pretty hard you stand to make up a test it's the right level and it's extremely hard to test without favoring those who've learned by rote and so I think that the rote learning as opposed to the free thinking unfortunately I don't know I said whether it necessarily wins out at the level of exams for university but it's it certainly gives people a great advantage so I think it's much harder now for people who just like to think on their own and not worry about exams too much and so on because it's become much more competitive I don't know how to do with that question so maybe the answer is just to procrastinate more yeah that's well there there's one they have them as people extra time and I may say my 18 year old son benefits he also suffer from her being a bit slow too but having a bit of extra time to do it was ok I think we'll come to the audience though we've got I'm gonna say about 10 minutes or so who would like to I've got a lot of hands going up straight wait we have microphones going round you may just have to oh there's what ok is one there to any other microphones oh that's the yeah I think so I call myself an atheist oh there's some people worried about that yes if you can find me okay let's say let's get a microphone is one just down here on the front row for kid we'll go one and then we'll come to you straight after and then we'll go over the other side afterwards go on shouts out for us we're hoes you mean I don't think wormholes are going to be any use I'm afraid despite the the film name what was it and it's a stellar yeah no I you see if you really think about general relativity and you try to me I think I'm partly responsible for wormholes I'm afraid so because I had a theorem which I proved that black holes produce singularities under very general circumstances and one of the conditions I had is that universe suddenly didn't do well it is that technically that you had what's called a Cosi surface and if you want to put that in the ordinary language you say somehow the universe doesn't joined onto another universe or something like that and so one had to send that Lew rather loose form and then some people picked up on that said Oh Penrose says you can might join unto another universe and that's the answer I disown it so I don't think it makes much sense these things are not stable and how on earth can you make a wormhole which is aimed where you want to go to I don't understand that at all but it's quantum entanglement no I don't think it there's some long locality no I'm it's fascinating feature of quantum mechanics that you have separated objects which somehow know something about each other not enough that they can communicate with each others it's a very subtle thing but more than them being independent it's between that sort of gap of being independent they're not independent they're slightly to do with each other but just not enough that they can send each other a signal which is a pretty subtle thing but quantum mechanics exhibits this phenomenon I think it tells you something quite different and that is that space-time structure there's something much deeper going on in the physics which is a long local description which gives you space-time as a sort of approximation it's a certain level but we don't have that yet okay we have a second question there hi so Parris I'm wondering if you know about Satya's recent work about fine structure coefficient and what do you think about it if you know fine structure constant and so recently has made Michael attea yeah yeah some doubt I prefer not to comment to that because I've never seen it I have hearsay I've heard I heard this because I wasn't sure that he wasn't making this as a claim that he didn't necessarily believe but he says he's an old man needs it allowed to do things like this right - he has done amazing things in his history and so he's allowed to play around with things which might be a bit controversial I don't know I've not seen it so I can't comment down there okay let's go over here wonder do we have any female questioners no even there we go okay perfectly can we go there and then I'll come over that side exactly good thank you the question was what would a model look like at infinite time well you see if it's my cosmic cosmology model essentially a time it's just this boundary I mean this is where you have to do the mathematics you see I've got this model with this it's you squash infinity down and then you stretch the Big Bang over the next day on out and it joins together now does that make sense you rather have equations which govern this transition from ones of the other so if you ask me that question what does it like well I got some crazy since we sell you what it looks like but I'm I'm not going to write I write them down I don't have a nice place to write them down but you can the point of view really is there's a way of looking at what happens in between which means different things are important it's hard to say but I used to worry about this you see suppose you had a time capsule and you had people they said this was so strong that people could keep in it and it would would survive right out to infinity or something like that but then in the model I have the trouble with that is that the matter in it would gradually lose its mass and it would start and whatever you made it off it would evaporate away and it wouldn't hold itself together so somehow everything in the limit becomes without mass and so it doesn't know what it feels like to be okay let's go over here so we could go well your nearest microphone this will go first to you and then we'll come to you after high Oh I've asked lots of people this question and no one seems to have to give me an answer say doing and do we know the answer is is gravity a force or in effect no one seems to know the answers no one's been able to answer that question to me and I'm I am NOT a scientist like I don't know what but what current view on that is partly depends on which community you're in it's a very ironic thing you see according to Einstein's general theory of relativity gravity is not a force it's the irony is you see how did the notion of force come back well Newton and you had these notions of force and all that's obvious second ball and whatever it was and all these things and the notion is force plays a role and the main candidate was gravity and you see look it works so beautifully you get these orbits and you get everything beautiful theory and then Newton also thought well they must be other forces with different laws maybe not inverse square law knows and he looked at this in spring keeper he'd studied different kinds of ways of different kinds of and now we have other kinds of forces in physics strong force the weak force and the electromagnetic force the charge electric force and all these things are what we now call forces but when you go back to gravity and you see well you just fall freely and you and it gone so it's not a force in the technical sense all these other things there is a difference which I can't go into there's a technical difference which means that gravity is something a bit different and in order for the principle of equivalence this is things falling together that the gravity Galilei a thing of a big mass and little mass falling together is something which holds only for gravity if you had an electric charge there are two electric charges and they had gravitation and say an electric charge at one end over the other they were fall completely differently it's only for gravity in which you have this principle equivalent so it's not a force in this refined way of looking however you can treat it as a force and often people do so the answer is a bit slippery out so yeah you treated as a force you do your Newtonian mechanics which is works extremely well and you often don't think it's in general relativity way and you of course just like every other force quantum mechanics you probably put a term in the Hamiltonian is do with any other force and you get away with it so you get away with it being a force but it's not in front of you you missed last time so if I gave you that and then I wrote I have I've got two questions everybody Joe on time because I think you all right you mentioned that you didn't like the term dark energy for cosmological constant if you had a free hand to put a new name out there a popular name what would it be the trouble with cosmological constants got all those syllables to it dark energy dark energy willis it's for cosmological constant mongrel lambda how about lambda lambda that's only two syllables call it lambda it's this capital I decide had a little lamb' them but the capital one is what they use now how about lambda is lambda yeah I think that's that's another bad name um dark energy just to get maybe it was this other question let me just answer you see they're too dark things this dark energy and this dark matter now I don't like either of those terms because they're not dark that's transparent you can see through them there is dust and that's dark and you can see pictures of a galaxies with a dark Street right across the middle that's dark but dark matter and dark energy no they're not dark the transparent but dark is our nice short word so that's why it is that how physicists pick words for things just a shortness of it's the shortness you had to say cosmological constant all the time from hearing it okay I think we have one question here and then I'm gonna ask one more so really we'll go we'll go t first and then you know the rest of you'll have to fight um can you tell us a little about what motivated you to come up with the very elegant ideas behind twister theory and are you still working in that area oh gosh I have the second question that was two questions I can ask to say the second is yes I am still working on it on that one but it's been stuck for about forty years and a certain problem but I think I know you see there's me being big-headed again I think we have the answer to that problem that's best sticking us live a thing called the googly problem which I think I know the way to do it but it's pretty difficult to do so I need some spare time or a good graduate student or about six graduate students actually they work on their elegance yes elegance was important in it but it's a complicated story I can't really go into this it wasn't just one thing you see there were if I could locate this page somewhere in one of my notebooks it I could remember what it is but I remember having a big page full of all sorts of connections between things which seem to me needed some unifying idea and that was what underlay Twista theory but that came about from [Music] okay the thing which really was the trigger was something very elegant in mathematics which I knew which was Clifford parallels people know about spheres they're not so familiar perhaps with spheres in four dimensions now in four dimensions you have the analog of sphere it's a three dimensional space it curves up and closes up on itself with a little practice you can get a feeling for this thing but Clifford described these things which people refer to as Clifford parallels so you have two things which are parallel well they're parallel they never meet you see but you can have kinds of geometries likely Beltrami picture I showed of hyperbolic geometry with a parallels don't meet they get further apart you can have of geometries where they come and they do meet so if you have a an ordinary spherical surface and you try to make two lines straight lines well you they have to be great circles they gradually come and meet now in the sphere in three a three sphere in four dimensions you could twist them a little bit so they don't meet they just first round each other and you can make them all circles and you fill the whole space with these circles and they twist around in this very very beautiful way which is known as Clifford para los and I known about these things for a long time in their very very elegant mathematical structure so when I realize that this thing in physics which to do with I can't go into it that there were C's solutions of the Maxwell's equations which also do the same thing and I realized that that was what I was looking for just work see see why they were that was why I was looking for I'd have to go into something too complicated to explain here but it was a revelation and I thought gosh and only because these are solutions of Maxwell's equations which I've already seen a colleague of mine had been studying and he knew these things now yeah that's it if I had to go back sit back home and and work it out and it was it was but then it took God the decades and decades to realize that did various things that it was supposed to do difficulty I'm still thinking on it now yes okay I realize I've gone horribly over time so that last one has to be a really quick question who's got a quick question okay let's go let's go for you there so if you could shout out just repeat the questions they people at the back there it was the half-life of a proton has been constrained to something like 10 to the 30 years and then the last bit was do you think that okay let me address that question the thing I need for this scheme is the 10 of the 30 years you must say okay that's nothing compared with ten to the hundred years which is what you need for black holes but the thing is where the protons protons go well they go if that's what happens to them they decay into into positrons and something the the electric charge has to be preserved so even if they decay into less massive particles which very possibly they do it depends on your particle physics theory I'm quite prepared to believe they do decay in terms of 30 years I don't know I don't have a view on that but they would decay because of an charge conservation into a charged particle so the problem I have is not so much with protons but with these charged smallest mass particles we have the electron and the positron and what about neutrinos well they don't have charged so I don't care too much about them they could they could be masses where they actually couldn't for a technical point but but it's really the in the positrons which is a problem now I'm not saying they decay because they know got nowhere to go what I am saying is that the very notion of mass fades out and that fade out comes about in this scheme it's not fully worked out but it comes about in this scheme because of lambda now you see in particle physics people one of the first things they do in particle physics is to classify particles according to what's called the Poincare a group and this has what's called two Casimir oh and I'm using technical jargon here but it has these two very important things called Casimir operators which commute well that's not a technical term with all the other operators of the group which means they have to be absolutely conserved what are they they're mass and spin now mass that means is a fundamental thing which mustn't if you have a stable particle it mustn't change but when you put lambda in it changes the game it introduces something a tiny little effect which means one of the Casimir operators where they're not mass and spin that suppose spin probably is not still but it's not mass you'll find it's corrected there's something I know know whether to make this into a good theory or not nobody's done it as far as I know but there's good reason to believe that when you put lambda in you're going to have a change and that mass is not completely absolutely constant and over time scales like when lambda starts to kick in as they say that's something like the current age of our universe from Big Bang to now which is what about four thousand million years that kind of time when is about the sort of scale when these kind of particles are going to start to lose a bit of their mass and then finally they would decay gradually and asymptotically become zero so that's that's the picture just to check when you say lambda there you do you're talking about dark energy yes absolutely general public yes they're ducking this okay unfortunately frankly I have to leave it there so a few of you I think have got VIP wristbands and are invited to a drink steps no in the mass gallery where Sir Roger will be the rest of you I'm afraid you're stuck with me but if you come don't stare as the gallery can come and say hi but I think all that remains I know I need to say it first we need to exit first if you give us a few seconds to leave before you ever until you follow us but all the remains really is to say an enormous thank you Roger for joining us I think we could have gone on all night it was absolutely fascinating thank you very much indeed [Applause] you

Channel: Oxford Mathematics

Views: 51,840

Rating: 4.9341383 out of 5

Keywords: Oxford Mathematics Public Lectures, Roger Penrose, Hannah Fry, Cosmology, Hawking Points, Maths Lecture, Physics Lecture

Id: 6BmWMm0Jtgk

Length: 81min 8sec (4868 seconds)

Published: Tue Nov 06 2018

Reddit Comments

[u/captainplanet171]

Then why is my phone's clock perpetually 5 minutes slow?

[u/Auricfire]

So, what I'm getting from this is that small ticks are just as important as big ticks, and no-one has any reason to be ashamed.

[u/[deleted]]

gif of head exploding

[u/highasakite91]

OK, OK, OK, there is a dick joke and a Yo Mama joke hiding in here. But I gonna let all you physicist dudes handle it. Cause daymn.

[u/chercheur17]

I'd say something like my balls are in their own space-time dimension, but that would be just puerile nonsense.