1 00:00:02,190 --> 00:00:29,690 As. Well, Roger, 2 00:00:29,690 --> 00:00:35,599 we've talked about how in the early days you started thinking about cosmology when people really knew absolutely nothing about cosmology at all. 3 00:00:35,600 --> 00:00:40,110 There was hardly anything about the stars that people would see. No, it's completely different. 4 00:00:40,130 --> 00:00:46,130 There's absolutely, absolutely gigantic amounts of data and huge numbers of people poring over them in every way. 5 00:00:47,080 --> 00:00:54,230 Uh, how? But you, I think, would feel that some quite fundamental things haven't really been answered at all. 6 00:00:54,260 --> 00:00:58,610 I mean, the role of the cosmological constant and then the origin of the. 7 00:01:00,600 --> 00:01:04,770 Well, yes. Tell me how you think things stand at the moment. 8 00:01:04,800 --> 00:01:15,690 Well, I do. I suppose I must think about things somewhat differently because the problems that I have regarded as important over the years at a time, 9 00:01:15,690 --> 00:01:25,020 scant attention these days. Well, I've always been very puzzled by the second law of thermodynamics and the direction of time and all that. 10 00:01:26,710 --> 00:01:37,450 And with the various things it has to do with which maybe are offshoots in one way or another, like how one conscious perception relates to it. 11 00:01:37,450 --> 00:01:45,400 But let's leave that aside for the moment. The main thing, which is a pretty obvious thing in a way, but which is almost totally ignored. 12 00:01:45,940 --> 00:01:50,170 Now, you see, we're supposed to have this big bang origin of the universe. 13 00:01:51,080 --> 00:02:00,840 And. If entropy, which is this measure of disorder, is increasing with time, it is what the second law tells us that means. 14 00:02:00,850 --> 00:02:06,569 Well, okay. It's understandable if I have a. Glass of water and a splash as it goes on the ground. 15 00:02:06,570 --> 00:02:11,340 And you don't see the opposite. That's entropy increasing. You don't see the entropy decreasing, but. 16 00:02:12,470 --> 00:02:17,300 If you state this the other way around, it's the same statement but just phrased in the opposite direction. 17 00:02:17,660 --> 00:02:21,650 It means as you go back in time, things get more and more and more ordered. 18 00:02:22,460 --> 00:02:27,680 Entropy goes down and down and down. And where do you get where you get to this thing called the Big Bang? 19 00:02:28,370 --> 00:02:31,460 And what's the best piece of evidence for the Big Bang? 20 00:02:31,820 --> 00:02:36,230 Well, it's this microwave background. You see this radiation coming from all directions. 21 00:02:36,830 --> 00:02:40,990 And this microwave background has one very important characteristic features. 22 00:02:41,450 --> 00:02:49,000 Very early on by Kobe. A mission that you see firm equilibrium. 23 00:02:49,010 --> 00:02:51,230 You see this beautiful spectrum, the Planck spectrum, 24 00:02:51,800 --> 00:02:57,860 which indicates that what you're looking at was in thermal equilibrium was not equilibrium really, because it was expanding. 25 00:02:58,220 --> 00:03:03,890 But taking that into account, that expansion is not an entropy increasing expansion. 26 00:03:03,890 --> 00:03:05,750 It's a diabetic expansion. 27 00:03:06,500 --> 00:03:16,130 And Tolman, the American cosmologist and physicists, fully appreciated that you were looking at something which was, in effect, thermal equilibrium. 28 00:03:17,120 --> 00:03:23,059 Now that is, on the face of it, a paradox, because surely when you go back in time, 29 00:03:23,060 --> 00:03:26,090 if the entropy is going down and down and down, it ought to be pretty small. 30 00:03:26,580 --> 00:03:29,930 Yet what you see is something telling you that entropy was at its maximum. 31 00:03:31,340 --> 00:03:35,570 Now it's never been said. You know, this is the great puzzle. Who says that? 32 00:03:35,720 --> 00:03:39,200 Well, I've been saying it, but hardly anybody else. 33 00:03:39,590 --> 00:03:45,950 Not only that, they don't say that, but they said this is what you expect in these standard cosmological models. 34 00:03:46,640 --> 00:03:52,250 If you take completely random initial set, you that's what you get and that's what you expect. 35 00:03:52,260 --> 00:03:57,470 And yeah, sure. And that's when they saw when Penzias and Wilson saw this thing. 36 00:03:58,010 --> 00:04:01,950 And Dickie. And people would say, yeah, well, that's what we expected to see. 37 00:04:03,680 --> 00:04:08,750 It's just the flash of the big bang you're seeing. Well, what about the entropy? 38 00:04:08,820 --> 00:04:14,510 How can that be? Well, I think there's some irony here because people. 39 00:04:15,580 --> 00:04:19,350 Tried to solve the Einstein equations for cosmology. And how do you solve them? 40 00:04:19,360 --> 00:04:23,920 Well, you assume symmetry, because otherwise the equations are just too hard to solve. 41 00:04:24,340 --> 00:04:29,590 And Friedman did this. He just assumed you have a very homogeneous, isotropic universe. 42 00:04:29,920 --> 00:04:38,380 And now he was able to solve the equations. Einstein was rather unhappy with his creations initially, but nevertheless he did it right. 43 00:04:38,950 --> 00:04:42,400 I certainly agree with his mathematics, but he thought he thought there must be something wrong somewhere. 44 00:04:42,730 --> 00:04:52,060 But it's curious that that it's these models which have been what people have used ever since and since they use them. 45 00:04:52,300 --> 00:05:01,630 It's just this is cosmology. And the fact that this is such an incredible assumption doesn't hit people. 46 00:05:01,960 --> 00:05:09,580 And this is where the entropy is low. It's because all the ripples in the spacetime that could have been there weren't there, 47 00:05:10,390 --> 00:05:14,260 and they were initially assumed not to be there because it's the only way they could solve the equations. 48 00:05:15,100 --> 00:05:19,570 But then you get used to the idea they're not there because those are the models. But why weren't they there? 49 00:05:20,410 --> 00:05:24,880 All these degrees of freedom in the gravitational free field could have been there. 50 00:05:25,420 --> 00:05:30,340 And to see how extraordinary this assumption is, 51 00:05:30,580 --> 00:05:35,950 you think of a collapsing universe which has all the irregularities, which might be there forms, black holes. 52 00:05:35,950 --> 00:05:45,790 These black holes congeal, the entropy goes soaring up incredibly now that we have this constant hawking formula for the entropy in a black hole. 53 00:05:46,210 --> 00:05:53,890 We now can make an estimate for how big that entropy is and how improbable the universe that we actually find ourselves to be in. 54 00:05:55,140 --> 00:06:01,770 See, you might have had that that puzzle even before the big and microwave background was discovered because 55 00:06:01,860 --> 00:06:06,840 that was attracted you to the to the Hoyle steady state model as a way of getting out of the Freedman. 56 00:06:06,900 --> 00:06:16,110 It's true that I thought about the you see, I did think about the second law issue very much in connection with the the steady state model. 57 00:06:16,620 --> 00:06:19,680 But there yeah, it was something that I worried about. 58 00:06:19,830 --> 00:06:27,600 But then it seemed that the problem could be solved with the picture that they have with the hydrogen being uniformly distributed. 59 00:06:27,960 --> 00:06:33,870 And then as it clump clumps into stars, that gives you an increase in the edge. 60 00:06:34,140 --> 00:06:37,650 It's a bright idea because that is with the wrong model. 61 00:06:37,680 --> 00:06:44,910 You see, you have a model with the hydrogen produced uniformly and as it clumps, it produces these hotspots. 62 00:06:45,450 --> 00:06:51,300 It's the action of gravity, and gravity produces hotspots, and the sun is a hotspot in the dark sky. 63 00:06:51,690 --> 00:06:57,509 And it's not that the sun is is hot, the sun is bright, gives us a life on the earth, 64 00:06:57,510 --> 00:07:01,710 because if so whole sky was the same temperature of the sun, it'd be utterly useless. 65 00:07:01,980 --> 00:07:07,860 It's the combination of the hot sun and the dark sky, and that's where the low entropy resides. 66 00:07:07,860 --> 00:07:14,810 And that comes about through gravity. So it was this crucial thing, which yeah, already when I was thinking about Steady State, 67 00:07:14,820 --> 00:07:18,090 I must have been thinking about that, although I can't quite pinpoint that. 68 00:07:18,690 --> 00:07:21,809 But that's true. I did. I did worry about second law then. 69 00:07:21,810 --> 00:07:29,040 But the fact that the hydrogen was dead is. Sharma Think about that too, because that's the sort of thing which I don't remember. 70 00:07:29,670 --> 00:07:40,300 Yes, you should have. But while I wrote this article for the day, Hawking and Hawking Israel with the Editors, The Einstein Centenary Volume. 71 00:07:41,020 --> 00:07:46,540 And this was I put this long article on about the study about the second law of thermodynamics. 72 00:07:48,850 --> 00:07:56,480 I don't think I had discussed all those things with Dennis beforehand. But I did not have the particular idea that I had subsequently that. 73 00:07:56,560 --> 00:08:03,680 Yes, yes. I didn't know how to characterise the particular way in which the Big Bang was special. 74 00:08:04,010 --> 00:08:08,360 And that really comes out of studying the conformal structure. I mean, that's that's one thing. 75 00:08:08,390 --> 00:08:15,650 Yes. Yes. In the earlier days, you wouldn't have, I think, had as much importance to you as you were in subsequent days. 76 00:08:17,040 --> 00:08:24,120 Well, there are a number of things I noticed very early on which played very important roles later on, but I couldn't figure out early. 77 00:08:24,510 --> 00:08:27,770 So one of them. Is this fact. 78 00:08:29,380 --> 00:08:37,690 Just just a curious fact in mathematics. We're talking about four dimensions and we're talking about space time for one time, three space, 79 00:08:38,170 --> 00:08:42,729 and we're talking about the vital curvature of our captures, the conformal curvature. 80 00:08:42,730 --> 00:08:49,020 So if you have a metric, you don't know what the scale of things is, but you know what angles are or if you know what the light codes are. 81 00:08:49,020 --> 00:08:54,640 That's another way of saying the same thing. That conformal structure tells you where the light comes out, but you don't know big from small. 82 00:08:55,420 --> 00:09:05,560 Then the characterisation of the curvature is in this lower curvature w e while the curvature is a measure of the conformal curvature, 83 00:09:05,920 --> 00:09:09,430 but it's also, in a sense, a measure of the gravitational degrees of freedom. 84 00:09:10,510 --> 00:09:16,649 Now. In connection with twisters, but not specifically twisters. 85 00:09:16,650 --> 00:09:20,520 I think it's thinking about it before that because I was looking at how you write in Spinners, 86 00:09:21,120 --> 00:09:24,810 the zero mass field equations for all the different spins. 87 00:09:25,260 --> 00:09:27,389 It was basically Dirac and though I had it, 88 00:09:27,390 --> 00:09:31,770 although when he did the zero maths case for some reason he did it a different way, which I never fully understood. 89 00:09:31,980 --> 00:09:35,400 But if you followed up Dirac's earlier paper and did it for zero maths, that's what you get. 90 00:09:35,820 --> 00:09:41,250 You have this particular way of writing the different spins and the Maxwell equations. 91 00:09:41,250 --> 00:09:46,549 You've just got to indices that and then use the. The graviton equation, if you like. 92 00:09:46,550 --> 00:09:52,130 You've got four indices. It's just the same equation. Neutrino equation is just one if you consider it massless. 93 00:09:52,640 --> 00:09:58,220 And so the the gravitational field is propagates and there's this wave equation. 94 00:09:58,670 --> 00:10:02,540 I had this interesting talk about slightly anecdotal things. 95 00:10:02,990 --> 00:10:08,990 Dirac never talked much, but I was a fellow at St John's College at the same time as director and a member at one 96 00:10:08,990 --> 00:10:13,970 point asking him whether I could have a chat with him about some of the stuff you see, 97 00:10:14,210 --> 00:10:19,490 because I knew he was interested in quantisation and relativity and so he agreed. 98 00:10:19,490 --> 00:10:23,750 And so he went off and had this and I started describing this spin of stuff to him. 99 00:10:24,840 --> 00:10:30,719 And I had this equation, this wave equation for me, for the for the spin to feel, you see. 100 00:10:30,720 --> 00:10:35,580 And I said, I wondered if this might have anything to do with Quantisation using the two spinners, which he had. 101 00:10:35,870 --> 00:10:39,839 It just absolutely does. But he didn't introduce the I don't know. 102 00:10:39,840 --> 00:10:46,979 Nobody even to me. Yeah, absolutely. That's right. And so what he said is this in the use of qualities, I don't know. 103 00:10:46,980 --> 00:10:50,550 You have to have a Hamiltonian, which is confidence so slightly. 104 00:10:50,700 --> 00:10:56,490 But then the other thing yes, the other thing about this credit is the words that he said to me, where does that equation come from? 105 00:10:57,150 --> 00:11:01,740 I said, Well, it comes from the bank identities. And he said, What are the banking identities? 106 00:11:02,490 --> 00:11:06,120 And I thought, what? You don't know what they're being. You see, I'm here. 107 00:11:06,120 --> 00:11:11,360 [INAUDIBLE] be doing all this quantisation. He obviously knew them. He just didn't know they were called the bank identities. 108 00:11:11,910 --> 00:11:15,950 He knew the contract, the contracted words. Because of all that. 109 00:11:16,090 --> 00:11:21,560 It was curious that I mean, I guess he he somebody who worked very much on his own, too. 110 00:11:21,570 --> 00:11:26,460 So he knew all these equations, but he had no idea that those were called the banking identities. 111 00:11:26,850 --> 00:11:29,910 That's a slight extra story. 112 00:11:30,150 --> 00:11:33,570 But the point was this came later. 113 00:11:33,810 --> 00:11:42,450 But the realisation that you had this propagation equation which made the gravitational equations look just like maximal equations, 114 00:11:42,450 --> 00:11:48,870 but first it's been to that's been one. I mean, this was done already by Pauli in physics or something, but they didn't do it this way. 115 00:11:49,170 --> 00:11:54,240 That is a much more complicated looking way. If you write in two spinners, it becomes completely obvious. 116 00:11:55,350 --> 00:11:59,610 But then I started worrying about the conformal invariants, these equations. 117 00:12:00,450 --> 00:12:08,609 And I was just struck by this curious fact that that equation is conformal, invariant with a particular weighting. 118 00:12:08,610 --> 00:12:14,630 Conformal, waiting for the spinner. And we already have the interpretation of the. 119 00:12:16,620 --> 00:12:22,710 Five curvature as being the conformal curvature, and therefore it has another conformal interpretation. 120 00:12:23,580 --> 00:12:26,220 So it's a conformal object, but the weighting is different. 121 00:12:26,760 --> 00:12:34,680 You have two different conformal weightings and it just strikes me, struck me there's something important here and I had no idea what it was. 122 00:12:35,760 --> 00:12:43,200 Well, so very much, much later when I realise it is absolutely crucial in a certain way. 123 00:12:44,370 --> 00:12:48,890 Which comes to this leap ahead. Yes. Because no, I will say yes. 124 00:12:48,900 --> 00:12:55,650 Those reasons. Well, you are asking me about about the what about second law and what I thought was important. 125 00:12:55,650 --> 00:12:58,900 And this big problem you see for a long, long time. 126 00:12:58,920 --> 00:13:03,910 I just thought, like everybody else, that the big bang. 127 00:13:03,930 --> 00:13:09,210 To understand it, we need quantum gravity. I mean, that's the that's the conventional view. 128 00:13:09,630 --> 00:13:13,950 We need quantum gravity. Maybe it's string theory. Quantum gravity. Maybe it's loop quantum gravity. 129 00:13:13,950 --> 00:13:18,120 Maybe it's this kind of going to gravity or the other kind of gravity or twist of quantum gravity. 130 00:13:18,600 --> 00:13:24,690 But it's quantum gravity. Now, that means to me what it meant to me. 131 00:13:25,050 --> 00:13:33,540 Quantum gravity must be a jolly funny theory, because the singularity is one of the reasons you're studying quantum gravity is to explain 132 00:13:33,540 --> 00:13:40,319 the Big Bang Singularity radius or see other singularities black holes that are utterly, 133 00:13:40,320 --> 00:13:41,340 completely different. 134 00:13:41,910 --> 00:13:48,120 People used to say, Well, you know, you've got singularities in the black holes that tell you got the singularities and the Big Bang singularity, 135 00:13:48,120 --> 00:13:52,110 the big bang F4 in the black holes, just the same thing. Times are going the other way around. 136 00:13:52,830 --> 00:13:56,700 But it's not that utterly different. But it's this entropy thing. 137 00:13:57,180 --> 00:14:04,650 The singularity is in black holes. Absolutely. While the curvature, while curvature goes completely dominates, Wales oscillates all over the place. 138 00:14:05,040 --> 00:14:08,330 Complete, complete madness. In the Big Bang. 139 00:14:10,460 --> 00:14:14,600 Com, as you could imagine. Think of the big bang as a great violent thing. 140 00:14:14,870 --> 00:14:21,730 But it's but it's utterly regular. Gravitation, degrees of freedom, simply not activated. 141 00:14:22,420 --> 00:14:28,870 Now, what kind of quantum gravity is going to give you these two utterly different extremes in the black hole? 142 00:14:29,530 --> 00:14:32,710 Complete domination by the vial. Curvature in the. 143 00:14:33,710 --> 00:14:38,930 Big Bang, while curvature seems to be zero, or at least very, very suppressed. 144 00:14:41,270 --> 00:14:48,709 Okay. My view then was to say, oh, a quantum gravity must be a jolly funny theory with the time, not time asymmetric. 145 00:14:48,710 --> 00:14:53,690 And if we're going to find quantum gravity here, you've got to put in time asymmetry somewhere else. 146 00:14:54,680 --> 00:15:02,300 So that was my view until, well, I guess about eight or nine. 147 00:15:02,390 --> 00:15:06,320 I forget how ago now it was that nine years ago. 148 00:15:07,790 --> 00:15:16,270 I just had this idea I was thinking about. But it took me a long time to be persuaded when I said a long time, maybe about three years, 149 00:15:16,510 --> 00:15:23,260 to be persuaded that the observations of these distant supernovae made by Perlmutter, 150 00:15:23,260 --> 00:15:32,770 Perlmutter and Schmidt and RIESS had and convincingly showed that the universe is accelerating in its expansion. 151 00:15:33,340 --> 00:15:38,410 And they it was all sort of touted as being this totally mysterious thing that nobody could understand. 152 00:15:38,440 --> 00:15:44,590 Totally unexpected. And I should say, we're going to look at the whole cosmology book's cosmological constant. 153 00:15:44,710 --> 00:15:48,160 Yeah, it's in all the cosmology books. I don't know why they thought it was. 154 00:15:48,640 --> 00:15:55,360 Why it should. I think we should explain. We're talking about dark energy, which is neither dark. 155 00:15:55,510 --> 00:15:58,930 No, no, no. It's a very bad name. Very bad name. 156 00:15:59,620 --> 00:16:08,770 But nevertheless, that's what people call it. And it's it's there apparently fits in absolutely perfectly as far as we know now 157 00:16:09,250 --> 00:16:14,890 with what the term ironsi introduced in 1917 for admittedly the wrong reason. 158 00:16:15,340 --> 00:16:21,490 And he wanted to start at Universe. Well, half of his right and that's the only the only modification you can make that generally. 159 00:16:22,000 --> 00:16:25,989 Absolutely. Yes. It's not just a term. It's not just a term. 160 00:16:25,990 --> 00:16:29,800 It is the one thing you can do to general relativity without wrecking it, basically. 161 00:16:29,890 --> 00:16:33,100 Yes. Without changing it in a radical way. 162 00:16:33,250 --> 00:16:37,890 That's right. And so often I would take into consideration. That's some tactics. 163 00:16:38,040 --> 00:16:45,030 The work I did in trying to look at squashing infinity down and making infinity look like a finite boundary, 164 00:16:45,420 --> 00:16:52,770 and you can use the conformal invariants in max with equations or of of this equation that you get for the propagation of gravitons. 165 00:16:52,770 --> 00:16:59,030 For that, it tells you what? How to study radiation feels by looking at infinity. 166 00:16:59,420 --> 00:17:06,920 And I also knew that if there was a cosmological constant which was positive, the surface would be space like it would be now. 167 00:17:07,040 --> 00:17:12,830 If it's not a zero cosmological constant time light, if it's negative, cosmological, constant. 168 00:17:13,370 --> 00:17:17,810 Fortunately, it's not negative because that causes all sorts of problems. 169 00:17:18,980 --> 00:17:24,350 Even though the string theorists seem to like it, a positive cosmological constant. 170 00:17:25,290 --> 00:17:29,760 Is a completely different class of problems. I used to think it had bad features. 171 00:17:30,510 --> 00:17:33,600 On reflection, it seemed to me there were just unusual features. 172 00:17:34,720 --> 00:17:41,560 But now it was absolutely crucial because I was thinking about the very remote future and how boring it was going to be in the 173 00:17:41,560 --> 00:17:47,510 very remote future where the black holes eventually disappear by hawking evaporation and there's nothing left of any interest. 174 00:17:47,530 --> 00:17:57,500 And this goes on to eternity. But to me, eternity is not such a long time because I'm thinking of compressing it down by this conformal scaling. 175 00:17:57,610 --> 00:18:01,480 This is what I mean by defeating time and go away. 176 00:18:02,740 --> 00:18:09,550 Yes. Well, the argument was basically I mean, I tend to use this in lectures as a sort of joke, but it's the real argument. 177 00:18:09,910 --> 00:18:16,239 You know, the universe gets so incredibly boring, but there won't be anybody of us, any of us around to be bored. 178 00:18:16,240 --> 00:18:21,160 But mainly it's photons and you can't verbal photons very easily. 179 00:18:22,000 --> 00:18:25,630 And so photons just go straight into this boundary. 180 00:18:26,770 --> 00:18:30,700 And the picture I was having and getting very used to it was the idea of a boundary, 181 00:18:30,970 --> 00:18:34,570 which if you've just got massive things, that boundary is like anywhere else. 182 00:18:35,860 --> 00:18:40,060 And then the thought occurred to me, Well, you've got the space like boundary for the big bang. 183 00:18:41,420 --> 00:18:45,230 My agent. You put them together. So it's an outrageous thought. 184 00:18:45,650 --> 00:18:53,450 And I gave lectures on this, usually being careful to call it an outrageous idea before anybody else said it was outrageous. 185 00:18:54,680 --> 00:18:58,970 But. As the years went by, I began to think more. 186 00:18:59,040 --> 00:19:04,500 But I think originally I would have given it a reasonable chance of being right. 187 00:19:05,550 --> 00:19:08,560 Reasonable chance. Maybe not 50%. There's no substance. 188 00:19:08,580 --> 00:19:12,030 Isn't that true? Paul Todd's work and the way you see Paul Todd? 189 00:19:12,030 --> 00:19:21,750 Yes. See, Paul Todd, I had the thing I called the vial curvature hypothesis, which was to say that the vial curvature as just a hypothesis, 190 00:19:22,770 --> 00:19:30,510 a way of characterising the big bang, that as you have an initial type singularity like the big bang, the vial curvature should be zero. 191 00:19:31,700 --> 00:19:36,680 But that's awkward to say because it's a singular state. What do you mean by tensor when it's singular and so on? 192 00:19:37,370 --> 00:19:42,530 So Paul had a much neater way of expressing it, which was to say, you stretch it out, 193 00:19:43,310 --> 00:19:48,050 stretch out the big bang mark and form a factor, which is something we did all the time for. 194 00:19:48,470 --> 00:19:56,450 Yeah, the Friedman models, that was quite a standard thing. But to make that the conditioned on the Big Bang I think is an important step. 195 00:19:57,750 --> 00:20:02,760 As Paul has originally, it only makes the vital curvature finite and doesn't necessarily zero. 196 00:20:03,420 --> 00:20:09,540 But as I already knew the infinity of outcomes, you must be zero because of the way these things scale. 197 00:20:09,620 --> 00:20:14,820 I said before that because there's a conformal factor in the scale, it must scale biochemistry to zero. 198 00:20:15,150 --> 00:20:20,790 So if you stick them together, the zero of curvature must propagate through to be zero on the next. 199 00:20:21,030 --> 00:20:25,770 Ian. So I started playing around with these ideas. 200 00:20:27,060 --> 00:20:30,480 Half thinking it was completely crazy. I suppose enough thinking it's probably right. 201 00:20:32,700 --> 00:20:36,170 And we end up with looking for circles in the sky. 202 00:20:36,180 --> 00:20:39,990 Yes, yes, absolutely. Actually, something we can actually see. 203 00:20:40,560 --> 00:20:43,950 Something to do with the mobius transformations of the sphere. 204 00:20:44,230 --> 00:20:47,550 Oh, well, that's what could be more beautiful. Is this prediction. 205 00:20:47,730 --> 00:20:51,150 It's. Well, you see, I was beginning. This didn't care. 206 00:20:51,150 --> 00:20:55,620 Immediately, I got people to ask me about, you know, how could you tell if this is right? 207 00:20:55,620 --> 00:20:59,970 And I thought sort of rather wrongly about gravitational radiation or something, 208 00:21:00,930 --> 00:21:05,910 but it was later that it occurred to me, what's the most violent thing that could happen? 209 00:21:06,450 --> 00:21:13,620 That might be a signal getting through. And so I was thinking of these collisions between supermassive black holes. 210 00:21:13,650 --> 00:21:21,450 You see, we're on a collision course with Andromeda, the Andromeda nebula, and it has a black hole, which is, I forget, 20, 50 times bigger than us. 211 00:21:22,170 --> 00:21:28,770 And we have a 4 million solar mass black hole and it's got a big one. 212 00:21:28,770 --> 00:21:31,620 And they could be on a collision course. 213 00:21:31,830 --> 00:21:41,010 They might well capture each other, spiral round boom when they swallow each other up, there will be one huge explosion in the form. 214 00:21:41,980 --> 00:21:44,680 Almost entirely of gravitational waves. 215 00:21:45,280 --> 00:21:51,190 And these gravitational waves, as I'm used to you at the boundary, they will come and they'll hit the boundary in a definite place. 216 00:21:52,030 --> 00:21:58,810 What will they do when they get through? Well, because of the scaling, they can't exist as gravitational waves on the other side. 217 00:21:59,350 --> 00:22:02,590 They have to scale down into another form. 218 00:22:03,310 --> 00:22:07,720 And the equations tell us that you have to have a new duck. 219 00:22:08,490 --> 00:22:16,660 Now, again, the word duck is a good one. But I think on the conformal cyclic cosmology scheme, which is what I'm talking about here. 220 00:22:17,700 --> 00:22:26,580 Simply acronym or what you see is the scheme tells us that the gravitation, the information, 221 00:22:26,610 --> 00:22:34,800 the gravitational waves propagates across but in the form of disturbances in this initial dark matter. 222 00:22:35,520 --> 00:22:41,340 So you have dark material created and it will be given the kick by this rotational wave impulse. 223 00:22:41,670 --> 00:22:43,290 They actually have another prediction, 224 00:22:43,290 --> 00:22:52,850 apart from the circular features corresponding to the outgoing gravitational wave of the gravitational radiation. 225 00:22:52,890 --> 00:22:56,520 You have a prediction for what dark matter will turn out. Yes. Is quite different. 226 00:22:56,550 --> 00:23:03,600 That is true. People who describe themselves and I haven't shouted about that because I mean, 227 00:23:03,610 --> 00:23:08,820 it's what I call the initial form of dark matter because it's massless originally it has to be massless. 228 00:23:09,090 --> 00:23:14,550 But the equations also tell you that you have to grow mass so that you can't keep massless. 229 00:23:14,560 --> 00:23:18,150 That's just an inconsistency. So the mass has to occur. 230 00:23:18,480 --> 00:23:21,900 It must be tied in with Higgs mechanisms and so on. 231 00:23:22,620 --> 00:23:28,450 It hasn't been as yet properly, but I think one has to understand more about particle physics. 232 00:23:29,040 --> 00:23:35,700 How does the Higgs mechanism new the creation of mass in the early universe relate to the appearance of mass, 233 00:23:36,330 --> 00:23:38,940 which comes in from the equations that you have here? 234 00:23:39,640 --> 00:23:46,379 And this is another huge area of your thought really is how conformal symmetry is broken in different ways and which is broken, 235 00:23:46,380 --> 00:23:50,390 which we see much more clearly by expressing things in twisted geometric terms. 236 00:23:50,460 --> 00:23:54,930 You see that breaking explicitly, but there are all these different aspects too. 237 00:23:55,410 --> 00:23:57,930 I've always been in two minds about that, yes. 238 00:23:58,470 --> 00:24:04,440 I suppose the cosmological constant has changed a bit because I used to think one of my minds was that you have the. 239 00:24:05,410 --> 00:24:12,069 If there's no cosmological constant, you have these Poincaré group twisters and that's you have a sort of exact sequence and 240 00:24:12,070 --> 00:24:17,110 exact sequences play a big role in a lot of cosmology and twisted theory and so on. 241 00:24:17,830 --> 00:24:26,660 But if you have a cosmological constant, you don't quite have an exact sequence, you have something which is inevitable and it changes one's attitude. 242 00:24:26,680 --> 00:24:34,690 So I think that was a shift. The cosmological constant took me a little while to get used to, but with the cosmology, it becomes absolutely crucial. 243 00:24:34,700 --> 00:24:38,210 You can't you can't do this cosmology without a cosmological constant. 244 00:24:38,690 --> 00:24:47,780 So you must have dark energy, as it's called, and you must have dark matter, as it's called, because that has to be a new created scaling material. 245 00:24:48,050 --> 00:24:55,580 Every time you go from one end to the next. And so therefore, in order that is not to pile up, it's got to decay away, too. 246 00:24:55,940 --> 00:25:04,940 So it must, throughout the history of energy on the dark matter decays away, which I believe there is some rather feeble evidence for. 247 00:25:05,330 --> 00:25:09,080 I don't know how much to trust it. I see most decay rather than clump together, which. 248 00:25:09,350 --> 00:25:13,579 Yes, well, it was a black hole for a bit, but then it must eventually decay. 249 00:25:13,580 --> 00:25:16,460 It must decay. Yeah. Otherwise it would build up. Yes. 250 00:25:16,520 --> 00:25:20,660 And then just build that for me on the end and then you won't have to have a way of propagating. 251 00:25:21,230 --> 00:25:27,020 So I think it's got to decay. But there are some it's not the evidence is not very strong. 252 00:25:27,020 --> 00:25:34,130 But I heard two bits of evidence. One was from a lecture given by Stephen Weinberg when he seemed to suggest that the density, 253 00:25:34,430 --> 00:25:39,260 the proportion of dark matter was larger in the very early universe than it is now. 254 00:25:40,130 --> 00:25:42,950 The other thing I picked up on are none of these. 255 00:25:43,100 --> 00:25:48,110 Neither these things may be right, but just picked up from because they sort of fit in with what I was thinking. 256 00:25:48,470 --> 00:25:56,030 The other one was there are observations of of paranoia and I think in the region near the centre well of positrons, 257 00:25:56,030 --> 00:26:01,940 I think that suggests that you see positrons or something in the region near the centre and they were these are co-products. 258 00:26:02,510 --> 00:26:09,380 I think there is, as you may know, there may be lots of use that it may be a decay product of dark matter. 259 00:26:10,430 --> 00:26:14,210 I had no idea then that no. Directly into photons they would go through. 260 00:26:14,270 --> 00:26:17,360 They go through. Yeah. Not photons but some. Yeah. 261 00:26:18,170 --> 00:26:22,520 I don't have strong views on that but it but it would, it would have to go eventually. 262 00:26:22,790 --> 00:26:29,910 Yeah. So dark matter. Yes. But then the other thing, there's a more recent thing to it. 263 00:26:30,390 --> 00:26:35,910 It may explain a lot of things you see, of course. And that's all the better, because there may be things that could contradict his. 264 00:26:35,910 --> 00:26:39,870 And if there are things that can contradicted, as Bondy used to say, with a steady state model, 265 00:26:40,230 --> 00:26:43,950 usually the steady state model is that it could be contradicted, and of course it was. 266 00:26:45,780 --> 00:26:58,110 So one has to look out for these things. But there is this information which was released in March of. 267 00:26:59,010 --> 00:27:14,010 This year, 2014 about these were called bicep2 observations where the claim is or was has been that this is the smoking gun of inflation. 268 00:27:14,490 --> 00:27:23,430 I haven't said anything about inflation, but I should say that in this model of nine, key inflation can't be there. 269 00:27:23,820 --> 00:27:25,710 It would spoil things. 270 00:27:26,460 --> 00:27:32,790 Inflation is supposed to have been this exponential expansion, which is supposed to have taken place in the very, very early stages of the universe. 271 00:27:34,330 --> 00:27:42,160 Initially the reasons put forward were ones that I always thought were just incorrect, having to do with the uniformity of the universe. 272 00:27:42,970 --> 00:27:46,780 And that only works if you've got a uniformity there. Originally it doesn't. 273 00:27:47,020 --> 00:27:50,410 You can see from general arguments that can't be an argument. 274 00:27:50,530 --> 00:27:53,890 There are good reasons, though, that kept inflation going. 275 00:27:54,280 --> 00:28:00,250 One of them being the scale invariance of the fluctuations in temperatures that you see in the microwave background. 276 00:28:01,060 --> 00:28:03,610 And if you don't have inflation, need another explanation. 277 00:28:04,150 --> 00:28:09,970 So to me, in a sense, there was inflation that was the exponential expansion of the Aeon prior to ours, 278 00:28:10,450 --> 00:28:15,430 which is similar to an idea that Veneziano put forward some years before the scheme of mind. 279 00:28:16,060 --> 00:28:22,720 So it's not a bad idea, but there are now much stronger constraints on what the inflationary I mean for people who 280 00:28:23,350 --> 00:28:29,580 mean for inflation is somewhat they can viably well it's the modes that they claim to see. 281 00:28:29,590 --> 00:28:38,950 There's a polarisation of photon polarisations that are seen probably are correctly seen in in the early universe. 282 00:28:39,430 --> 00:28:47,080 But the conclusion that is made is that you see these things which couldn't arise from purely magnetic features. 283 00:28:47,320 --> 00:28:50,620 They have to be so purely electric. They have to be magnetic. 284 00:28:52,200 --> 00:28:55,890 They Yukos, which they couldn't have. It was purely electric. 285 00:28:57,390 --> 00:29:02,760 Now, Paul Todd was talking to me earlier this year about. 286 00:29:05,380 --> 00:29:09,670 Problems that there were about the creation of primordial magnetic fields. 287 00:29:09,760 --> 00:29:13,120 And there are difficulties in ordinary cosmology about where they come from. 288 00:29:13,990 --> 00:29:18,970 You partly see them in magnetic fields in these voids, regions where there are no galaxies. 289 00:29:19,420 --> 00:29:21,640 Well, how on earth did the magnetic fields come about? 290 00:29:22,210 --> 00:29:27,550 And the view seems to be that they must have been there right from the Big Bang and those who produce beamers. 291 00:29:28,060 --> 00:29:33,219 So the idea is not just that the beam modes that claim are claim to be the 292 00:29:33,220 --> 00:29:38,620 smoking gun of inflation and nothing of the sort but primordial magnetic fields. 293 00:29:39,250 --> 00:29:47,350 And that those magnetic fields, according to the suggestion that Paul made to me, is that maybe they came through from the previous year, which. 294 00:29:48,350 --> 00:29:55,250 They would on this scheme because they'd be attached to galactic clusters and those little places where the galactic cluster. 295 00:29:56,210 --> 00:29:59,870 Impinges on the crossover surface. You have magnetic fields. 296 00:30:00,910 --> 00:30:03,220 And then there was just very recently. 297 00:30:06,630 --> 00:30:14,130 I was hearing about these things you said and was very rather alarmed by the Beamers and the fact that they seem to be proving inflation. 298 00:30:14,130 --> 00:30:21,870 So everybody said since that would disprove. You see, inflation can't coexist with it for various reasons. 299 00:30:22,710 --> 00:30:28,380 So I began thinking, well, maybe these are the things policy claiming should be there. 300 00:30:29,370 --> 00:30:32,979 And then I. Emails. 301 00:30:32,980 --> 00:30:42,340 My colleague by Gosden, who had met the person initially who had seen the evidence of these circular features, concentric circular features, 302 00:30:42,340 --> 00:30:49,840 because these would be each time there's a black hole collision in the galactic cluster, there would be, boom, you see, that's one ring. 303 00:30:50,410 --> 00:30:52,720 A little bit later, another one, boom. There's another ring. 304 00:30:53,080 --> 00:30:57,160 And these would always be concentric because the central point is where that galactic cluster ends up. 305 00:30:58,300 --> 00:31:03,910 So he was looking for looking at least three rings where the variance, 306 00:31:03,910 --> 00:31:09,190 the variation of temperature around the ring is lower by a certain amount than the average. 307 00:31:09,850 --> 00:31:19,270 And this was the test we were using for these things. And he claims to see lots of indications of these things, very non isotropic over the sky, 308 00:31:19,600 --> 00:31:23,590 certain regions where huge numbers of them, other regions are practically nothing. 309 00:31:24,340 --> 00:31:29,889 So when I heard about the beam, I said, well, I emailed this, you know, where is this region? 310 00:31:29,890 --> 00:31:34,650 They're saying these things. Can you pinpointed on the sky? So he put a little ring. 311 00:31:34,660 --> 00:31:40,110 So it's in here. And this was in in his Planck map. 312 00:31:40,320 --> 00:31:47,880 So this was the recent more recently old ones with the W Matt when he looked at the plank map once and I looked at this picture. 313 00:31:48,060 --> 00:31:51,540 Nothing whatsoever in that set up. Oh, dear. 314 00:31:52,110 --> 00:31:58,560 So I look back at the old w matt ones, same place and bang there was a triple of rings right in the middle. 315 00:31:59,850 --> 00:32:06,450 So then I emailed back and I said, well. Why don't I see them in the blank data? 316 00:32:06,720 --> 00:32:11,760 So they said, Oh, well, I'll turn up the volume a bit. Didn't say quite like that. Looking at slightly lower signals. 317 00:32:12,060 --> 00:32:17,090 And there there they are, absolutely right in the middle. More over. 318 00:32:17,340 --> 00:32:21,360 Moreover, if these are pulled towards. 319 00:32:21,680 --> 00:32:30,450 Well, if the beamers really are magnetic fields and if these rings are really from that galactic cluster in the previous aeon, 320 00:32:31,050 --> 00:32:34,920 it's only just on the edge. Just from the geometry, it has to be where our past. 321 00:32:34,920 --> 00:32:38,700 Like it's where the galactic cluster ends up. 322 00:32:39,540 --> 00:32:43,350 And therefore, the temperature of these rings must be average. 323 00:32:44,010 --> 00:32:48,060 See, the the distant ones, that signal is coming towards us and therefore warmer. 324 00:32:48,600 --> 00:32:52,050 The close ones signal is going away faster and therefore cooler. 325 00:32:52,440 --> 00:32:56,460 The ones which are just on the edge would be of average temperature. 326 00:32:56,560 --> 00:33:00,840 I look at these rings, they're right. The colour coding is green, which means right in the middle. 327 00:33:01,710 --> 00:33:08,610 So this is sort of exciting. Yes, it is. If this is right, when we can make prediction, well, we make the predictions anyway. 328 00:33:08,610 --> 00:33:14,160 But we see because the Planck data hasn't come out yet on this. 329 00:33:14,730 --> 00:33:20,970 And so it looks as though we might make a prediction of the sorts of places to look for where you should see birds. 330 00:33:21,870 --> 00:33:26,400 Because those and if that's right see this is a second observational. 331 00:33:28,020 --> 00:33:32,740 Feature of the scheme. But nobody pays any attention to the first one yet. 332 00:33:33,790 --> 00:33:40,390 It's been almost completely ignored. I mean, there were exciting verifications of this. 333 00:33:40,410 --> 00:33:43,620 We had last September. 334 00:33:43,860 --> 00:33:53,310 Yes. Yeah. Well, Christoph Meissner gave a very nice talk where he explained his analysis, which is quite different from from Vargas John's analysis. 335 00:33:53,970 --> 00:33:57,520 And he also saw significant evidence for these rings. 336 00:33:57,560 --> 00:34:01,530 Yes. I guess looked at in a different way. But yes, it's the same the same feature. 337 00:34:03,060 --> 00:34:06,960 But again. Oh, no, no attention paid. 338 00:34:09,660 --> 00:34:13,830 Uh, on some different subject predictions. 339 00:34:14,040 --> 00:34:18,030 How do you think things stand on the evidence of quantum mechanical? 340 00:34:18,980 --> 00:34:22,640 Dependence, the biological structure of the brain. 341 00:34:22,820 --> 00:34:27,000 And this is also you. There have been some interesting things in recent years. 342 00:34:27,020 --> 00:34:33,980 Yes. Well, you see, first I should explain that I wrote my book, The Emperor's New Mind, 343 00:34:35,060 --> 00:34:42,110 hoping that by the time I got to the end of the book, I would have some inkling of quantum effects could be relevant to the brain. 344 00:34:42,110 --> 00:34:48,170 And I couldn't. There was it wasn't it kind of petered out there, but it did have the advantage. 345 00:34:48,210 --> 00:34:51,440 I mean, I thought maybe I would inspire young people to do physics or something. 346 00:34:52,550 --> 00:34:58,850 It was more rather ancient retired people who wrote to me or else it was somebody of a scientific subject. 347 00:34:58,850 --> 00:35:06,610 And one of these was Stuart Harmer, who did read my book and he said, Well look, you may not know about these things called microtubules. 348 00:35:06,620 --> 00:35:09,800 It's just, say, migrants. I never heard of them at that time. 349 00:35:11,010 --> 00:35:13,979 These are the things that in mitosis, when the cell divides, 350 00:35:13,980 --> 00:35:18,900 you'll see the chromosomes being pulled apart and these microtubules are dragging them apart. 351 00:35:19,230 --> 00:35:24,870 They play all sorts of roles in cells generally, but they seem to have a particular role, according to Stewart anyway. 352 00:35:24,870 --> 00:35:31,229 Stuart Nemeroff that they play a particular role in consciousness in the brain and his 353 00:35:31,230 --> 00:35:37,260 business professional activity is putting people to sleep as an anaesthesiologist. 354 00:35:38,460 --> 00:35:44,400 Arizona. And so unlike maybe many of his colleagues who are just interested in putting people to sleep, 355 00:35:44,820 --> 00:35:48,000 he's sort of interested in actually what he's doing when he's putting people to sleep. 356 00:35:48,600 --> 00:35:54,060 So and his idea has been and he tells me that there is now some good evidence that this is the case, 357 00:35:54,540 --> 00:35:58,200 that general anaesthetics do act on directly on microtubules. 358 00:35:58,740 --> 00:36:09,020 So these are little nanoscale tubes which are in all sorts of almost all cells in the body and in neurones. 359 00:36:09,030 --> 00:36:14,850 But the argument is that they have a different role in neurones and that they play a central role in consciousness. 360 00:36:15,030 --> 00:36:17,850 Something very interesting has come up on several things. 361 00:36:18,300 --> 00:36:26,700 One is some observation about where you can track where the consciousness kind of appears, what part of the brain is involved. 362 00:36:27,390 --> 00:36:34,410 And one thing that always worried me for a long time about most explanations of consciousness in terms of computation or something, 363 00:36:34,980 --> 00:36:39,970 is why is the cerebellum not conscious? It seems to be entirely unconscious. 364 00:36:40,270 --> 00:36:47,380 Yet there are about half as many neurones in the brain and far more connections between neurones in the cerebellum and in the cerebrum. 365 00:36:47,680 --> 00:36:51,550 Yet the cerebrum seems to be where consciousness comes about. 366 00:36:52,660 --> 00:36:58,060 Well, these new observations have to do with these things called pyramidal cells. 367 00:36:59,080 --> 00:37:06,670 There are six parameter cells, which are the sort of cells which look like pyramids, I suppose. 368 00:37:07,540 --> 00:37:09,430 But they don't occur in the cerebellum at all. 369 00:37:09,760 --> 00:37:17,050 They occur in certain parts of the brain, which is now identified as the major part where consciousness does come about. 370 00:37:17,560 --> 00:37:23,060 And they are absolutely packed with microtubules, apparently. So this is one interesting development. 371 00:37:23,270 --> 00:37:25,310 It sort of alters the picture somewhat. 372 00:37:25,670 --> 00:37:31,100 But I've always been worried by why the cerebellum, with all these connections and so on, why isn't that indicate? 373 00:37:31,340 --> 00:37:38,390 Why is that unconscious? But it seems to be it doesn't have these particular types of cells, and that may be a crucial thing. 374 00:37:38,660 --> 00:37:43,910 But the other important development has to do with the experimental findings of. 375 00:37:45,810 --> 00:37:51,570 And have been. Bandyopadhyay, who has been doing experiments largely in Japan with colleagues, 376 00:37:51,570 --> 00:37:59,640 is an Indian doing experiments there and on individual microtubules where they measure the resistance with particular frequencies. 377 00:37:59,880 --> 00:38:07,620 He finds that they're very particular frequencies where thing becomes extremely conductive in ways which are quite unlike classical conduction. 378 00:38:09,930 --> 00:38:17,040 You see, I had the this complicated, roundabout route for thinking that quantum mechanics has to be playing a role, 379 00:38:17,040 --> 00:38:20,400 and not just quantum mechanics, but beyond quantum mechanics. 380 00:38:21,080 --> 00:38:24,389 So it's not just outrageous because people used to think, oh, well, 381 00:38:24,390 --> 00:38:29,130 brain is all wet and messy, and how can you have coherent quantum mechanics going on there? 382 00:38:30,090 --> 00:38:33,330 But I'm saying not only that, it's got to be at the level. 383 00:38:34,560 --> 00:38:39,510 Extend it to the level where you start to see divergence from standard quantum mechanics. 384 00:38:39,540 --> 00:38:45,480 Now, that's totally outrageous, you see. But my reasoning came from the girl things and saying, Well, 385 00:38:46,440 --> 00:38:54,810 really seems that our understanding cannot be something of a purely computational character. 386 00:38:55,410 --> 00:38:59,969 And it's very interesting because, of course, with Turing saved in his early years, 387 00:38:59,970 --> 00:39:05,150 he was very I think he would been very alive to these questions much more than people who follow. 388 00:39:05,170 --> 00:39:10,110 I can I can't imagine his computational model as a dog and as a because he 389 00:39:10,110 --> 00:39:16,259 wrote this paper on Ordinal Logics and which was trying to go beyond systems. 390 00:39:16,260 --> 00:39:22,589 And yeah, I mean, it's very difficult to tell. I mean, I think the success of computational methods during the war really got him going. 391 00:39:22,590 --> 00:39:25,739 I think explore how much you could go in that direction. 392 00:39:25,740 --> 00:39:30,330 But he was certainly worried about the fact that quantum physics is actually quantum mechanical. 393 00:39:30,360 --> 00:39:34,410 Yeah, yeah. No, he's alive to that in a way that other people not exposed to. 394 00:39:34,920 --> 00:39:41,100 But then you see, normally one would think you could you could compute this to any degree of accuracy as a sort of argument. 395 00:39:41,100 --> 00:39:44,400 Maturing himself would make that what have what the Schrodinger equation does. 396 00:39:45,090 --> 00:39:52,319 But then the standard quantum mechanics you then have to use the Schrodinger equation only is probabilistic, but then you have to have a measurement. 397 00:39:52,320 --> 00:39:55,770 Well, he was very aware of the reductionist. Yes, that's right. They've been real too. 398 00:39:55,800 --> 00:39:59,060 Yeah. Because I mean, you got that directly from von Neumann. That's right. That's it. 399 00:39:59,070 --> 00:40:02,260 Which is probably also how you would. Yes. Yes, that's right. 400 00:40:02,430 --> 00:40:05,690 That's my was the first professor of that very much. Yes. Yes. 401 00:40:06,390 --> 00:40:12,650 So. But what's interesting is that now in biology, 402 00:40:12,650 --> 00:40:17,660 it's not just in these microtubules because that's Bandyopadhyay has observations 403 00:40:17,660 --> 00:40:21,620 which do seem to indicate something very strange is going on in microtubules, 404 00:40:22,130 --> 00:40:26,000 which certainly is not classical. And how you explain it quantum mechanically. 405 00:40:26,000 --> 00:40:30,320 Well, that's people don't even know how to explain high temperature superconductivity properly yet. 406 00:40:30,770 --> 00:40:33,080 So this there are lots of things to understand there. 407 00:40:33,530 --> 00:40:43,489 But now we know photosynthesis involves entanglements, essentially quantum mechanical effects, some things about nothing but bird navigation. 408 00:40:43,490 --> 00:40:45,050 Is it? I think it is something. 409 00:40:46,380 --> 00:40:53,820 Sensitivity to magnetic fields or some of these these things do seem to tell us that there is a lot more going on in biology, 410 00:40:53,820 --> 00:41:00,150 which you simply can't explain purely classically perfume, apart from chemistry, which is already quantum mechanical. 411 00:41:01,140 --> 00:41:02,520 But you see, 412 00:41:02,520 --> 00:41:14,669 I'm saying you've got to have enough quantum mechanics that it's coherent across many neurones in a way which allows sufficient displacement of mass. 413 00:41:14,670 --> 00:41:23,220 According to the scheme that I tried to develop with Doshi originally had a scheme like this and then for different with different motivations i. 414 00:41:24,660 --> 00:41:28,770 Picked up on that idea, very similar, which is that when in severe variations, 415 00:41:28,770 --> 00:41:35,070 if there's a mass enough mass displacement, then it goes over into classical alternatives. 416 00:41:35,760 --> 00:41:42,630 But this is very frowned upon by most quantum mechanics people, because they think that quantum mechanics has to hold. 417 00:41:43,650 --> 00:41:50,850 Invariably at all levels. But all experiments to date have only been at a level where you don't probe this area. 418 00:41:51,970 --> 00:41:55,270 So there's experiments hiding in the wings there, too. 419 00:41:57,160 --> 00:42:02,590 Well, thank you very much, Roger, for giving this talk. Well, time again, time is dominating. 420 00:42:02,800 --> 00:42:04,210 Well, it's been a great pleasure for me. 421 00:42:04,390 --> 00:42:14,260 It's always a pleasure to talk about these things and try to rake up as I maybe inspire someone who's watching this, to think it would be nice. 422 00:42:14,260 --> 00:42:17,060 Who really knows? Who knows, right? Okay.