1 00:00:08,240 --> 00:00:11,519 Hello, and welcome to the first Physics World 2 00:00:11,519 --> 00:00:14,099 weekly podcast of 2026. 3 00:00:14,400 --> 00:00:15,699 I'm Hamish Johnston. 4 00:00:16,295 --> 00:00:19,595 In this episode, I'm in conversation with Alex 5 00:00:19,655 --> 00:00:20,155 May, 6 00:00:20,535 --> 00:00:22,315 who is the Murray Gautman 7 00:00:22,695 --> 00:00:24,954 Chair in Theoretical Physics 8 00:00:25,255 --> 00:00:26,795 at the Perimeter Institute 9 00:00:27,175 --> 00:00:28,635 in Waterloo, Canada. 10 00:00:29,359 --> 00:00:30,820 Much of Alex's research 11 00:00:31,199 --> 00:00:34,880 explores how quantum information theory can help us 12 00:00:34,880 --> 00:00:35,380 solve 13 00:00:35,840 --> 00:00:37,460 one of the most enduring 14 00:00:37,760 --> 00:00:39,140 mysteries in physics. 15 00:00:39,760 --> 00:00:40,899 How to reconcile 16 00:00:41,440 --> 00:00:42,420 quantum mechanics 17 00:00:42,855 --> 00:00:43,594 with Einstein's 18 00:00:44,135 --> 00:00:45,835 general theory of relativity 19 00:00:46,454 --> 00:00:50,635 to create a viable theory of quantum gravity. 20 00:00:51,575 --> 00:00:54,535 Our conversation is coming up after this message 21 00:00:54,535 --> 00:00:55,195 of support 22 00:00:55,509 --> 00:00:56,729 from the APS 23 00:00:57,269 --> 00:00:58,809 Global Physics Summit, 24 00:00:59,429 --> 00:01:02,879 which takes place on March 25 00:01:02,879 --> 00:01:04,969 2026 26 00:01:05,269 --> 00:01:06,650 in Denver, Colorado, 27 00:01:07,349 --> 00:01:08,409 and online. 28 00:01:09,185 --> 00:01:12,244 At the largest physics meeting in the world, 29 00:01:12,465 --> 00:01:14,564 you can join thousands of physicists, 30 00:01:15,024 --> 00:01:15,524 students, 31 00:01:15,905 --> 00:01:18,884 and policy leaders for a week of connection 32 00:01:19,185 --> 00:01:19,924 and collaboration. 33 00:01:21,040 --> 00:01:21,859 Immerse yourself 34 00:01:22,239 --> 00:01:25,599 in the cutting edge science that's shaping our 35 00:01:25,599 --> 00:01:26,659 shared future, 36 00:01:27,119 --> 00:01:29,060 and be part of the global 37 00:01:29,439 --> 00:01:30,420 physics community 38 00:01:30,959 --> 00:01:32,099 driving innovation 39 00:01:32,640 --> 00:01:33,140 forward. 40 00:01:33,935 --> 00:01:38,674 Explore the meeting at summit.aps.org. 41 00:01:47,350 --> 00:01:50,810 I'm at the Perimeter Institute in Waterloo, Ontario, 42 00:01:51,030 --> 00:01:53,189 and I'm very pleased to be joined by 43 00:01:53,189 --> 00:01:54,170 Alex May. 44 00:01:54,709 --> 00:01:56,490 Hi, Alex. Welcome to the podcast. 45 00:01:57,109 --> 00:01:59,109 Hey, Hamish. How are you doing? I'm fine. 46 00:01:59,109 --> 00:02:01,895 Thanks. And I'm very excited to chat with 47 00:02:01,895 --> 00:02:06,075 you about the intersection between quantum information theory 48 00:02:06,534 --> 00:02:08,075 and quantum gravity. 49 00:02:08,615 --> 00:02:10,775 So can we start off maybe with a 50 00:02:10,775 --> 00:02:11,754 few definitions? 51 00:02:12,455 --> 00:02:14,634 What is quantum information 52 00:02:15,175 --> 00:02:17,310 theory? Can you give us a a simple 53 00:02:17,310 --> 00:02:18,769 take on it if possible? 54 00:02:19,469 --> 00:02:20,370 Yeah. So, 55 00:02:20,669 --> 00:02:22,750 there's lots of context we're familiar with where 56 00:02:22,750 --> 00:02:23,969 we're interested in 57 00:02:24,349 --> 00:02:26,449 doing what we might call information processing. 58 00:02:27,069 --> 00:02:28,289 So when you, 59 00:02:28,830 --> 00:02:31,564 run a program on your computer, you're processing 60 00:02:31,625 --> 00:02:34,025 information in some way. When I send you 61 00:02:34,025 --> 00:02:35,865 a message over the Internet or over the 62 00:02:35,865 --> 00:02:36,365 phone, 63 00:02:37,465 --> 00:02:38,205 we are, 64 00:02:39,145 --> 00:02:41,145 yeah, again, processing information in a different way. 65 00:02:41,145 --> 00:02:43,564 In that case, we're communicating instead of computing. 66 00:02:44,185 --> 00:02:46,479 There's other aspects about, you know, how you 67 00:02:46,479 --> 00:02:47,699 keep information secure, 68 00:02:48,479 --> 00:02:49,620 so that's called cryptography. 69 00:02:50,639 --> 00:02:51,139 And 70 00:02:51,439 --> 00:02:54,800 what quantum information theory is, is you're taking 71 00:02:54,800 --> 00:02:56,500 the properties of quantum mechanics, 72 00:02:56,800 --> 00:02:58,319 all the things that are weird and and 73 00:02:58,319 --> 00:03:00,995 cool about it, and seeing how it changes 74 00:03:01,134 --> 00:03:02,814 what you can do when it comes to 75 00:03:02,814 --> 00:03:04,935 information processing. So how how does the strangeness 76 00:03:04,935 --> 00:03:06,034 of quantum mechanics 77 00:03:06,495 --> 00:03:09,055 help us compute better, help us open up 78 00:03:09,055 --> 00:03:11,215 new possibilities in how we communicate, in how 79 00:03:11,215 --> 00:03:13,770 we keep information secure, and and so on. 80 00:03:13,849 --> 00:03:15,930 I see. And and it can be very 81 00:03:15,930 --> 00:03:17,129 useful, can't it? 82 00:03:17,530 --> 00:03:19,710 Quantum well, the the quantum mechanics, 83 00:03:20,409 --> 00:03:20,909 itself, 84 00:03:21,290 --> 00:03:23,770 there are some benefits to to using it 85 00:03:23,770 --> 00:03:25,069 in a in an information 86 00:03:25,689 --> 00:03:28,335 paradigm, isn't there? Yeah. That's right. So the 87 00:03:28,335 --> 00:03:30,594 most famous example is with quantum computing. 88 00:03:30,974 --> 00:03:32,835 So there's lots of excitement about that. 89 00:03:33,215 --> 00:03:35,155 There are certain problems that, 90 00:03:36,014 --> 00:03:37,794 our understanding is that using, 91 00:03:38,735 --> 00:03:40,735 computers based on the principles of quantum mechanics, 92 00:03:40,735 --> 00:03:42,115 we can solve them quickly, 93 00:03:42,960 --> 00:03:43,780 even while 94 00:03:44,080 --> 00:03:46,580 a traditional computer, what's called a classical computer, 95 00:03:46,800 --> 00:03:48,240 would really struggle. It would take a long, 96 00:03:48,240 --> 00:03:50,480 long time. There's lots of other ways that 97 00:03:50,480 --> 00:03:52,719 we can get advantages out of using quantum 98 00:03:52,719 --> 00:03:55,439 mechanics, though, beyond computing, which is maybe what 99 00:03:55,439 --> 00:03:56,354 you hear about the most. 100 00:03:56,914 --> 00:03:57,394 So, 101 00:03:57,875 --> 00:04:00,294 another subject is what's called quantum key distribution. 102 00:04:00,995 --> 00:04:03,875 So that's where using properties of quantum mechanics 103 00:04:03,875 --> 00:04:04,694 to let you, 104 00:04:04,995 --> 00:04:07,155 communicate securely in a way that's that's not 105 00:04:07,155 --> 00:04:08,055 possible otherwise. 106 00:04:08,354 --> 00:04:09,479 I see. Right. 107 00:04:10,519 --> 00:04:12,199 And, Alex, you know, sort of, 108 00:04:13,159 --> 00:04:15,000 when you look at it, you know, maybe 109 00:04:15,000 --> 00:04:17,000 naively, that seems like a million miles away 110 00:04:17,000 --> 00:04:18,220 from quantum gravity, 111 00:04:18,680 --> 00:04:19,180 which, 112 00:04:19,560 --> 00:04:21,160 you know, it I mean, seems to be 113 00:04:21,160 --> 00:04:21,819 a very 114 00:04:22,439 --> 00:04:23,259 sort of esoteric 115 00:04:24,125 --> 00:04:24,625 field. 116 00:04:25,725 --> 00:04:27,725 And I I just wanted to to get 117 00:04:27,725 --> 00:04:30,625 started with quantum gravity by asking you, 118 00:04:31,245 --> 00:04:34,225 why why don't we have a a good 119 00:04:34,925 --> 00:04:35,425 understanding 120 00:04:35,725 --> 00:04:38,779 or theory of quantum gravity? What what is 121 00:04:38,779 --> 00:04:40,240 the what are the challenges 122 00:04:40,779 --> 00:04:43,979 that you and other physicists are encountering when 123 00:04:43,979 --> 00:04:45,919 you're trying to develop theories? 124 00:04:46,379 --> 00:04:47,740 Yeah. So I think I think there's lots 125 00:04:47,740 --> 00:04:50,294 of ways of understanding what goes wrong with 126 00:04:50,294 --> 00:04:52,615 our usual approach to to understanding, you know, 127 00:04:52,615 --> 00:04:54,074 a quantum theory with that 128 00:04:54,375 --> 00:04:55,814 or what goes wrong when you deal with 129 00:04:55,814 --> 00:04:56,794 gravity in particular. 130 00:04:57,814 --> 00:04:58,794 So one 131 00:04:59,254 --> 00:05:01,334 one way to understand this is in the 132 00:05:01,334 --> 00:05:03,035 language of field theory. So 133 00:05:03,479 --> 00:05:04,939 in quantum field theories, 134 00:05:06,199 --> 00:05:07,720 field theories are sort of come in two 135 00:05:07,720 --> 00:05:10,060 types. So there's renormalizable ones and nonrenormalizable 136 00:05:10,439 --> 00:05:10,939 ones. 137 00:05:11,479 --> 00:05:11,979 And, 138 00:05:12,759 --> 00:05:15,660 maybe without specifying exactly what that means, 139 00:05:16,305 --> 00:05:18,145 the the high the high level picture is 140 00:05:18,145 --> 00:05:19,444 that a renormalizable 141 00:05:19,824 --> 00:05:20,324 theory 142 00:05:20,705 --> 00:05:23,585 kind of makes sense at all energies. K. 143 00:05:23,585 --> 00:05:25,105 So it makes sense. We can make low 144 00:05:25,105 --> 00:05:27,264 energy predictions, but it continues to make sense 145 00:05:27,264 --> 00:05:28,004 at high energy. 146 00:05:28,410 --> 00:05:30,649 The theory might not be experimentally correct at 147 00:05:30,649 --> 00:05:32,410 high energy, but the theory itself is not 148 00:05:32,410 --> 00:05:34,569 telling you that there's something wrong at high 149 00:05:34,569 --> 00:05:35,069 energy. 150 00:05:35,930 --> 00:05:36,830 A non renormalizable 151 00:05:37,209 --> 00:05:37,709 theory, 152 00:05:38,009 --> 00:05:40,269 it's the other way. So it's 153 00:05:40,810 --> 00:05:42,810 it knows that something is wrong with it 154 00:05:42,810 --> 00:05:44,455 at high energies. You try and make a 155 00:05:44,455 --> 00:05:46,555 prediction of high energy, it gives you infinity, 156 00:05:46,615 --> 00:05:48,154 something something goes wrong. 157 00:05:48,855 --> 00:05:49,355 So 158 00:05:49,814 --> 00:05:50,314 gravity, 159 00:05:51,014 --> 00:05:52,455 you know, we have a theory of gravity. 160 00:05:52,455 --> 00:05:54,314 We have Einstein's general relativity. 161 00:05:54,774 --> 00:05:56,855 You can cast that as a as a 162 00:05:56,855 --> 00:05:57,675 field theory, 163 00:05:58,139 --> 00:06:00,379 as a quantum field theory, and it makes 164 00:06:00,379 --> 00:06:01,519 sense at lower energies. 165 00:06:01,819 --> 00:06:03,120 Right? So you can do, 166 00:06:04,060 --> 00:06:06,720 you know, the kind of physics relevant 167 00:06:07,180 --> 00:06:09,579 to maybe planets orbiting around stars or something 168 00:06:09,579 --> 00:06:11,740 like that using general relativity or or in 169 00:06:11,740 --> 00:06:13,985 this field theory framework, and and everything's okay. 170 00:06:14,605 --> 00:06:15,105 But 171 00:06:16,685 --> 00:06:17,185 the 172 00:06:17,645 --> 00:06:19,105 the fact that this theory is nonrenormalizable 173 00:06:19,564 --> 00:06:21,425 is telling you that if you try and 174 00:06:21,645 --> 00:06:23,404 use this at very high energy scales, if 175 00:06:23,404 --> 00:06:25,004 you try and use our understanding of gravity 176 00:06:25,004 --> 00:06:26,625 at high at high energies, 177 00:06:28,045 --> 00:06:29,720 things go wrong. Okay. 178 00:06:30,500 --> 00:06:32,819 That by itself is not so bad. Right? 179 00:06:32,819 --> 00:06:34,900 So there's lots of other field theories that 180 00:06:34,900 --> 00:06:37,560 had been written written down that were nonrenormalizable 181 00:06:38,660 --> 00:06:40,199 that we later figured out, 182 00:06:41,845 --> 00:06:44,004 you know, were just some other more detailed 183 00:06:44,004 --> 00:06:46,805 field theory at at high energies. So you 184 00:06:46,805 --> 00:06:48,585 can write down a field theory that describes 185 00:06:48,884 --> 00:06:49,384 neutrons, 186 00:06:49,925 --> 00:06:51,545 and it's not were normalizable. 187 00:06:53,285 --> 00:06:55,205 It's telling you that above some energy scale, 188 00:06:55,205 --> 00:06:56,964 there's some new physics that this theory doesn't 189 00:06:56,964 --> 00:06:57,420 know about. 190 00:06:57,900 --> 00:06:59,819 The new physics isn't that wild. It's just 191 00:06:59,819 --> 00:07:01,580 saying that, oh, actually, neutrons are made out 192 00:07:01,580 --> 00:07:02,160 of some 193 00:07:02,540 --> 00:07:04,220 constituent particles, and if you go to high 194 00:07:04,220 --> 00:07:06,060 energies, you're gonna see that. So your original 195 00:07:06,060 --> 00:07:07,980 theory didn't see that didn't didn't know about 196 00:07:07,980 --> 00:07:09,279 those particles. Right? 197 00:07:11,235 --> 00:07:13,415 We actually know that with gravity, 198 00:07:13,715 --> 00:07:14,935 the solution is not 199 00:07:15,715 --> 00:07:18,035 as simple as that. So there's a theorem 200 00:07:18,035 --> 00:07:19,495 called the Weinberg Witten theorem 201 00:07:19,875 --> 00:07:22,295 tells you that the graviton, like the basic 202 00:07:22,355 --> 00:07:24,455 excitation in your theory of gravity 203 00:07:25,089 --> 00:07:25,830 is not, 204 00:07:26,930 --> 00:07:28,689 it's not just some composite particle. It's not 205 00:07:28,689 --> 00:07:29,970 gonna break apart when you go up to 206 00:07:29,970 --> 00:07:30,870 go to high energies. 207 00:07:31,250 --> 00:07:32,850 That's not where the new physics is coming 208 00:07:32,850 --> 00:07:33,350 from. 209 00:07:34,930 --> 00:07:37,110 So instead, there has to be some 210 00:07:37,625 --> 00:07:38,285 more exotic, 211 00:07:39,625 --> 00:07:41,644 new physics that happens at high energies, 212 00:07:42,264 --> 00:07:44,824 and the challenge is in identifying what that 213 00:07:44,824 --> 00:07:45,324 is. 214 00:07:45,625 --> 00:07:48,685 I see. And and in your research, 215 00:07:49,544 --> 00:07:51,884 a a lot of your research focuses on 216 00:07:52,379 --> 00:07:53,439 non local 217 00:07:53,819 --> 00:07:55,040 quantum computation, 218 00:07:55,979 --> 00:07:58,959 I suppose, as applied to quantum gravity. 219 00:08:00,060 --> 00:08:01,199 What is NLQC, 220 00:08:01,899 --> 00:08:03,839 and why is it important 221 00:08:04,300 --> 00:08:07,039 to, study? Why are you interested in it? 222 00:08:07,285 --> 00:08:08,504 Yeah. Okay. So 223 00:08:09,285 --> 00:08:10,964 maybe we can we can sort of continue 224 00:08:10,964 --> 00:08:12,805 with with the story of that I was 225 00:08:12,805 --> 00:08:15,045 trying to describe in the last question where, 226 00:08:15,045 --> 00:08:16,584 you know, we know that there's some, 227 00:08:17,685 --> 00:08:20,165 maybe sort of exotic new physics coming in 228 00:08:20,165 --> 00:08:20,324 at 229 00:08:21,079 --> 00:08:22,540 that's relevant to high energies. 230 00:08:23,959 --> 00:08:27,000 One possibility that's been identified for a long 231 00:08:27,000 --> 00:08:27,500 time 232 00:08:28,360 --> 00:08:28,860 is, 233 00:08:29,160 --> 00:08:30,620 goes goes by the name of the holographic 234 00:08:30,680 --> 00:08:31,180 principle. 235 00:08:31,720 --> 00:08:33,799 Okay. And so this is this is the 236 00:08:33,799 --> 00:08:34,299 claim, 237 00:08:34,840 --> 00:08:35,340 that 238 00:08:36,875 --> 00:08:39,195 the reason this theory of gravity isn't working 239 00:08:39,195 --> 00:08:40,495 at high energies is that, 240 00:08:41,514 --> 00:08:43,034 or at least the way to get around 241 00:08:43,034 --> 00:08:44,254 this is to 242 00:08:44,634 --> 00:08:46,735 give some alternative description of gravity 243 00:08:47,995 --> 00:08:50,714 in one less dimension than we would usually 244 00:08:50,714 --> 00:08:52,235 think it would live in. So we live 245 00:08:52,235 --> 00:08:54,139 in a three plus one dimensional 246 00:08:54,600 --> 00:08:55,100 space, 247 00:08:56,919 --> 00:08:59,720 and the holographic principle suggests that there's some 248 00:08:59,720 --> 00:09:01,580 just two plus one dimensional description 249 00:09:02,120 --> 00:09:05,054 of this world. Okay? Or, you know, four 250 00:09:05,054 --> 00:09:07,294 dimensional gravity is described in terms of some 251 00:09:07,294 --> 00:09:07,794 three-dimensional 252 00:09:08,174 --> 00:09:11,154 non gravitating, just quantum mechanical theory. 253 00:09:12,975 --> 00:09:15,534 So this this sounds a little bit crazy. 254 00:09:15,534 --> 00:09:17,215 It's saying that we kind of live in 255 00:09:17,215 --> 00:09:18,995 some lower dimensional hologram, 256 00:09:20,410 --> 00:09:22,649 but it's well motivated. You know, one way 257 00:09:22,649 --> 00:09:24,090 to motivate it is from this kind of 258 00:09:24,090 --> 00:09:26,570 Weinberg Witten description or picture that I was 259 00:09:26,570 --> 00:09:29,129 that I was describing, but another comes from 260 00:09:29,129 --> 00:09:31,070 the physics of black holes. So 261 00:09:31,865 --> 00:09:33,004 with a black hole, 262 00:09:34,184 --> 00:09:37,225 we've identified that the entropy of the black 263 00:09:37,225 --> 00:09:39,725 hole seems to be given by the area 264 00:09:39,865 --> 00:09:40,684 of the hole. 265 00:09:41,065 --> 00:09:42,985 And so this is somehow saying that the 266 00:09:42,985 --> 00:09:44,745 amount of information in the black hole, the 267 00:09:44,745 --> 00:09:45,964 number of degrees of freedom, 268 00:09:46,584 --> 00:09:47,084 is 269 00:09:47,399 --> 00:09:49,720 not like the volume, like you would expect 270 00:09:49,720 --> 00:09:50,539 for an ordinary, 271 00:09:51,159 --> 00:09:53,339 an ordinary system, but somehow, 272 00:09:54,120 --> 00:09:55,879 there's fewer degrees of freedom and there's only 273 00:09:55,879 --> 00:09:57,500 an area's worth. Okay. 274 00:09:57,959 --> 00:09:59,879 And we think that not just black holes, 275 00:09:59,879 --> 00:10:00,620 but actually, 276 00:10:01,404 --> 00:10:03,644 everything sort of works like that. So, you 277 00:10:03,644 --> 00:10:05,024 know, we think we have sort 278 00:10:05,404 --> 00:10:07,745 of three dimensions worth of degrees of freedom, 279 00:10:07,804 --> 00:10:08,304 but, 280 00:10:09,804 --> 00:10:12,605 apparently, there's there's this lower dimensional description in 281 00:10:12,605 --> 00:10:13,424 terms of just 282 00:10:13,804 --> 00:10:15,745 two dimensions worth of degrees of freedom. 283 00:10:16,769 --> 00:10:19,009 Okay. So that that's part of the exotic 284 00:10:19,009 --> 00:10:20,610 physics that seems to take over at at 285 00:10:20,610 --> 00:10:22,449 high energies when you're trying to do quantum 286 00:10:22,449 --> 00:10:22,949 gravity. 287 00:10:24,929 --> 00:10:25,429 So 288 00:10:25,970 --> 00:10:26,949 okay. So 289 00:10:27,730 --> 00:10:28,049 now, 290 00:10:29,495 --> 00:10:32,235 what is the subject of nonlocal quantum computation, 291 00:10:32,294 --> 00:10:33,995 and and how is it related here? 292 00:10:35,254 --> 00:10:36,875 Well, to get to that, 293 00:10:37,735 --> 00:10:38,235 let's 294 00:10:38,695 --> 00:10:40,535 go to a very different setting for a 295 00:10:40,535 --> 00:10:42,934 second. So this is a setting in quantum 296 00:10:42,934 --> 00:10:43,914 information theory. 297 00:10:45,179 --> 00:10:47,439 In particular, it's a setting in, 298 00:10:47,740 --> 00:10:48,480 in cryptography. 299 00:10:49,500 --> 00:10:50,000 K? 300 00:10:50,459 --> 00:10:52,159 So cryptography is all about, 301 00:10:53,179 --> 00:10:55,120 establishing trust, keeping secrets, 302 00:10:55,500 --> 00:10:58,079 processing information securely, so on. 303 00:10:58,695 --> 00:10:59,175 And, 304 00:10:59,495 --> 00:11:01,095 one thing that you could be interested in 305 00:11:01,095 --> 00:11:02,394 doing in that context 306 00:11:03,095 --> 00:11:03,595 is, 307 00:11:04,134 --> 00:11:05,035 is in checking 308 00:11:05,415 --> 00:11:08,774 where physically in space somebody is. So you're 309 00:11:08,774 --> 00:11:10,455 talking to somebody, you're talking to them over 310 00:11:10,455 --> 00:11:11,274 the phone, say, 311 00:11:12,200 --> 00:11:13,960 but you wanna know that the person you're 312 00:11:13,960 --> 00:11:15,980 talking to is located in a certain spot. 313 00:11:16,279 --> 00:11:16,779 Right? 314 00:11:17,320 --> 00:11:18,600 You might wanna do that as a way 315 00:11:18,600 --> 00:11:20,840 of establishing trust. Right? We often trust people 316 00:11:20,840 --> 00:11:22,440 based on where they are. You know, you 317 00:11:22,440 --> 00:11:23,259 go to the bank, 318 00:11:23,985 --> 00:11:25,664 you go to the person behind the till, 319 00:11:25,664 --> 00:11:27,024 you take out your wallet, you give them 320 00:11:27,024 --> 00:11:29,105 your money, your information. You've never met this 321 00:11:29,105 --> 00:11:31,264 person. You didn't check their ID. You trust 322 00:11:31,264 --> 00:11:33,745 them because they're behind the till. Right? So 323 00:11:33,745 --> 00:11:35,345 you might use location as a sort of 324 00:11:35,345 --> 00:11:36,804 proxy for for trust. 325 00:11:38,464 --> 00:11:38,705 So 326 00:11:39,959 --> 00:11:40,459 okay. 327 00:11:41,000 --> 00:11:43,480 So starting with that idea, there's this subject 328 00:11:43,480 --> 00:11:44,459 in quantum cryptography 329 00:11:44,839 --> 00:11:45,339 around 330 00:11:46,120 --> 00:11:47,980 trying to check where somebody is. 331 00:11:48,759 --> 00:11:51,179 And what was realized by the cryptographers 332 00:11:51,815 --> 00:11:53,735 is that you could use this technique, which 333 00:11:53,735 --> 00:11:55,514 is this non local quantum computation, 334 00:11:56,454 --> 00:11:59,674 to always allow somebody to cheat in this, 335 00:12:00,214 --> 00:12:01,815 in this kind of scenario where you're trying 336 00:12:01,815 --> 00:12:03,834 to check where they are. And in particular, 337 00:12:04,134 --> 00:12:05,514 what they realized is 338 00:12:05,860 --> 00:12:06,360 if 339 00:12:06,820 --> 00:12:09,320 you think you're interacting with somebody sort of 340 00:12:09,379 --> 00:12:10,600 inside of some volume, 341 00:12:12,500 --> 00:12:15,299 the responses that that person gives you, right, 342 00:12:15,299 --> 00:12:16,660 I give you some inputs, they give you 343 00:12:16,660 --> 00:12:17,320 some outputs, 344 00:12:18,164 --> 00:12:20,884 Those responses can always be simulated by somebody 345 00:12:20,884 --> 00:12:22,424 who's hanging out near the boundary 346 00:12:23,284 --> 00:12:23,684 of, 347 00:12:24,644 --> 00:12:26,664 of that volume where you're supposed to be. 348 00:12:27,605 --> 00:12:31,000 So that's unfortunate for the for the for 349 00:12:31,000 --> 00:12:33,100 the cryptographic goal. Right? It's saying that there's, 350 00:12:33,480 --> 00:12:35,079 at least in a in a very general 351 00:12:35,079 --> 00:12:36,220 context, no way 352 00:12:37,079 --> 00:12:39,079 to to be sure about where the person 353 00:12:39,079 --> 00:12:40,220 you're talking to is, 354 00:12:40,600 --> 00:12:41,980 but it has this very 355 00:12:42,679 --> 00:12:44,459 interesting connection to this 356 00:12:45,274 --> 00:12:48,154 this holography idea from point of gravity, and 357 00:12:48,154 --> 00:12:49,054 that it's saying, 358 00:12:49,674 --> 00:12:52,414 you know, anything happening in this volume 359 00:12:53,035 --> 00:12:55,375 can be replaced by something happening 360 00:12:55,914 --> 00:12:57,375 at the boundary of that volume. 361 00:12:58,100 --> 00:12:59,940 And that sounds a lot like calligraphy where 362 00:12:59,940 --> 00:13:02,360 it's saying, oh, there's a three-dimensional script description, 363 00:13:02,659 --> 00:13:04,980 but there's some alternative, you know, two dimensional 364 00:13:04,980 --> 00:13:06,839 description or lower dimensional description. 365 00:13:09,299 --> 00:13:11,320 So, yeah, that's kind of the starting point. 366 00:13:11,699 --> 00:13:12,440 There's some 367 00:13:13,075 --> 00:13:14,774 similarity between these subjects. 368 00:13:15,554 --> 00:13:16,214 And then, 369 00:13:16,754 --> 00:13:18,355 you can start trying to make this connection 370 00:13:18,355 --> 00:13:18,855 precise. 371 00:13:20,115 --> 00:13:22,615 And, to do that, you need some precise, 372 00:13:23,875 --> 00:13:25,254 theory of quantum gravity. 373 00:13:26,309 --> 00:13:26,789 And, 374 00:13:27,350 --> 00:13:29,029 the way that that's the context in which 375 00:13:29,029 --> 00:13:30,389 this has all been made most precise is 376 00:13:30,389 --> 00:13:32,089 something called the AdS CFT correspondence. 377 00:13:33,350 --> 00:13:35,509 And there, we find that, you know, these 378 00:13:35,509 --> 00:13:37,529 results that cryptographers had proven 379 00:13:37,884 --> 00:13:38,704 years ago 380 00:13:39,245 --> 00:13:41,824 about nonlocal computation lead to very precise 381 00:13:42,284 --> 00:13:45,245 and new statements about gravity and ADS space 382 00:13:45,245 --> 00:13:48,384 times, and that's quite a, a surprising connection. 383 00:13:49,004 --> 00:13:50,865 I see. And and so 384 00:13:51,324 --> 00:13:53,959 how how do you so you've got this 385 00:13:53,959 --> 00:13:56,440 correspondence. You can show I'm guessing you can 386 00:13:56,440 --> 00:13:57,259 show mathematically 387 00:13:58,039 --> 00:14:01,419 that it's that there's a strong correspondence between 388 00:14:01,879 --> 00:14:02,700 these two, 389 00:14:03,720 --> 00:14:06,299 well, that sound very, very different Yeah. 390 00:14:06,839 --> 00:14:07,339 Concepts. 391 00:14:07,835 --> 00:14:10,014 How how does that help you 392 00:14:10,715 --> 00:14:11,855 come up with a theory 393 00:14:12,394 --> 00:14:16,235 of quantum gravity? Does that is that are 394 00:14:16,235 --> 00:14:17,695 these like building blocks 395 00:14:18,075 --> 00:14:19,134 that you can use? 396 00:14:19,595 --> 00:14:20,575 Yeah. So AdSCFT 397 00:14:20,955 --> 00:14:23,210 is, I mean, we can't prove it mathematically. 398 00:14:23,210 --> 00:14:25,370 It's a conjecture. There's lots of evidence for 399 00:14:25,370 --> 00:14:27,210 it. We can we can check many aspects 400 00:14:27,210 --> 00:14:28,750 of it, and it seems to work out. 401 00:14:29,610 --> 00:14:31,050 But well, maybe I should say first of 402 00:14:31,050 --> 00:14:32,490 all what it is. It's it's a claim 403 00:14:32,490 --> 00:14:32,990 that 404 00:14:33,924 --> 00:14:36,325 two very apparently very different looking theories are 405 00:14:36,325 --> 00:14:36,825 actually 406 00:14:37,205 --> 00:14:37,705 equivalent. 407 00:14:39,684 --> 00:14:42,085 So the two theories would be, a higher 408 00:14:42,085 --> 00:14:45,205 dimensional gravitating theory and then a lower dimensional 409 00:14:45,205 --> 00:14:47,465 just quantum mechanical theory, like like the holographic 410 00:14:47,524 --> 00:14:49,019 principle says we should have. 411 00:14:51,980 --> 00:14:52,480 It's 412 00:14:53,179 --> 00:14:55,899 within a certain context. So this doesn't apply 413 00:14:55,899 --> 00:14:59,660 to all theories of gravity. Right? It applies 414 00:14:59,660 --> 00:15:01,500 to theories of gravity that live in a 415 00:15:01,500 --> 00:15:03,259 special kind of a space time called the 416 00:15:03,259 --> 00:15:03,759 asymptotically 417 00:15:04,139 --> 00:15:05,625 ADF space. K. 418 00:15:06,085 --> 00:15:06,585 That's 419 00:15:07,205 --> 00:15:09,205 it's a little unfortunate that it only applies 420 00:15:09,205 --> 00:15:10,585 to that kind of space time, 421 00:15:12,165 --> 00:15:14,404 in that we don't think that we actually 422 00:15:14,404 --> 00:15:17,524 live in an asymptotically ADS space. We live 423 00:15:17,524 --> 00:15:18,245 in a, 424 00:15:19,045 --> 00:15:20,759 somewhat different looking space time. 425 00:15:21,399 --> 00:15:23,639 But, you know, nonetheless, this is some kind 426 00:15:23,639 --> 00:15:26,279 of working, at least toy model of quantum 427 00:15:26,279 --> 00:15:29,639 gravity. It's saying, here's this gravitational physics. It's 428 00:15:29,639 --> 00:15:32,700 recorded into just some quantum mechanical physics, 429 00:15:33,884 --> 00:15:35,964 and it's up to us to study how 430 00:15:35,964 --> 00:15:37,504 these things fit into each other, 431 00:15:38,125 --> 00:15:40,544 try and extract the key ideas there, 432 00:15:40,924 --> 00:15:42,464 and then from that, 433 00:15:43,245 --> 00:15:45,485 hopefully go and use those ideas to describe, 434 00:15:45,485 --> 00:15:47,904 you know, quantum gravity in the actual universe. 435 00:15:48,284 --> 00:15:51,289 I see. And the the this quantum cryptography 436 00:15:51,589 --> 00:15:52,730 system, does that, 437 00:15:53,750 --> 00:15:55,029 I mean, does that give you, 438 00:15:56,149 --> 00:15:57,129 an analog 439 00:15:57,509 --> 00:15:58,490 that you can, 440 00:15:58,950 --> 00:16:01,429 I don't know, manipulate and probe or, I 441 00:16:01,429 --> 00:16:02,730 mean, even do experiments 442 00:16:03,065 --> 00:16:05,245 in the lab that could inform 443 00:16:06,184 --> 00:16:08,605 your your understanding of quantum gravity? 444 00:16:09,304 --> 00:16:09,804 Yeah. 445 00:16:10,825 --> 00:16:12,605 I I would say, like, in 446 00:16:13,784 --> 00:16:15,910 in a certain sense, it's it's 447 00:16:16,290 --> 00:16:19,170 a totally quantum mechanical analog of of at 448 00:16:19,170 --> 00:16:21,330 least one aspect of what happens in ADS 449 00:16:21,330 --> 00:16:21,830 CFT. 450 00:16:22,210 --> 00:16:24,529 It's not like a full model or something 451 00:16:24,529 --> 00:16:25,490 like that, but I think it, 452 00:16:27,424 --> 00:16:30,544 it explains and captures, like, one aspect of 453 00:16:30,544 --> 00:16:31,924 the physics in ADS CFT. 454 00:16:34,464 --> 00:16:37,044 That, like, so far has just been used 455 00:16:38,384 --> 00:16:40,884 at the level of, like, here's some mathematical 456 00:16:41,024 --> 00:16:44,089 result around nonlocal computation, and then 457 00:16:44,710 --> 00:16:46,490 here's how we apply it to ADSCFT. 458 00:16:47,830 --> 00:16:50,070 And it leads to, you know, maybe some 459 00:16:50,070 --> 00:16:51,210 theorem about gravity, 460 00:16:51,589 --> 00:16:53,289 some precise consequence there. 461 00:16:54,549 --> 00:16:56,409 I think you could start thinking about 462 00:16:57,595 --> 00:16:59,995 things like, you know, how do I make 463 00:16:59,995 --> 00:17:00,975 a quantum system 464 00:17:01,754 --> 00:17:03,995 that is doing one of these nonlocal quantum 465 00:17:03,995 --> 00:17:04,494 computations 466 00:17:05,434 --> 00:17:06,794 and is doing it in a way that, 467 00:17:06,794 --> 00:17:09,294 like, looks more like a gravitating system? 468 00:17:09,994 --> 00:17:11,595 And then can I go and build that 469 00:17:11,595 --> 00:17:12,414 in my lab? 470 00:17:12,900 --> 00:17:13,400 And, 471 00:17:13,940 --> 00:17:16,119 yeah, that's a question that you could ask. 472 00:17:16,180 --> 00:17:17,400 I I guess I, 473 00:17:19,700 --> 00:17:20,600 I don't have 474 00:17:21,140 --> 00:17:22,279 a sharp question 475 00:17:23,940 --> 00:17:25,940 about ADS CFT that I want to try 476 00:17:25,940 --> 00:17:27,015 and answer that way, 477 00:17:28,055 --> 00:17:29,575 but I think it could be worth exploring. 478 00:17:29,575 --> 00:17:33,115 Yeah. I see. And before we started recording, 479 00:17:33,734 --> 00:17:35,815 we we were chatting a bit about the 480 00:17:35,815 --> 00:17:39,660 intersection of quantum gravity and quantum information. Yeah. 481 00:17:40,140 --> 00:17:41,980 I mean, I'm guessing that what we've just 482 00:17:41,980 --> 00:17:43,759 been talking about is probably 483 00:17:44,220 --> 00:17:46,700 just a small That's right. Aspect. Can can 484 00:17:46,700 --> 00:17:48,460 you talk a bit, you know, about the 485 00:17:48,460 --> 00:17:50,220 field in general? Is this sort of a 486 00:17:50,220 --> 00:17:51,580 growing field that, 487 00:17:52,460 --> 00:17:55,519 theorists are becoming more and more interested in? 488 00:17:56,035 --> 00:17:58,595 Yeah. So definitely yeah. I should emphasize the 489 00:17:58,595 --> 00:18:00,434 the the thing I was describing is one 490 00:18:00,434 --> 00:18:02,855 one aspect of this broader, 491 00:18:03,234 --> 00:18:04,775 deeper connection between, 492 00:18:06,035 --> 00:18:08,595 quantum information theory and and quantum gravity and 493 00:18:08,595 --> 00:18:11,490 and especially the ADFCFT correspondence, but but even 494 00:18:11,490 --> 00:18:13,509 more broadly in quantum gravity than that. 495 00:18:16,210 --> 00:18:16,710 And, 496 00:18:17,329 --> 00:18:19,009 yeah, I think one one question I get 497 00:18:19,009 --> 00:18:19,990 a lot about, 498 00:18:21,170 --> 00:18:23,029 you know, these two fields is, like, 499 00:18:23,455 --> 00:18:25,475 why is there any connection at all? 500 00:18:26,975 --> 00:18:28,914 I think there's different ways to understand that. 501 00:18:29,535 --> 00:18:31,475 One way to understand it is just that, 502 00:18:32,815 --> 00:18:35,215 in a sense, quantum information theory, you know, 503 00:18:35,215 --> 00:18:37,049 was built up to answer the kind of 504 00:18:37,130 --> 00:18:39,049 somewhat practical questions that I was describing. How 505 00:18:39,049 --> 00:18:40,809 do we compute better? How do we communicate 506 00:18:40,809 --> 00:18:41,309 better? 507 00:18:41,930 --> 00:18:43,289 You know, this is about stuff we want 508 00:18:43,289 --> 00:18:44,910 to do, stuff we want to build. 509 00:18:45,769 --> 00:18:47,610 But when you try and answer those questions, 510 00:18:47,610 --> 00:18:48,890 one thing that you end up doing is 511 00:18:48,890 --> 00:18:51,049 just end up developing a whole new way 512 00:18:51,049 --> 00:18:52,430 to understand quantum mechanics. 513 00:18:53,345 --> 00:18:53,845 And, 514 00:18:55,345 --> 00:18:57,765 you know, powerful tools for for, 515 00:18:58,065 --> 00:19:00,305 you know, just understanding interesting properties of quantum 516 00:19:00,305 --> 00:19:01,285 mechanics. Right? 517 00:19:01,825 --> 00:19:03,825 And so much of the physics that we 518 00:19:03,825 --> 00:19:04,325 do, 519 00:19:04,865 --> 00:19:07,500 right, is in that quantum mechanic is in 520 00:19:07,500 --> 00:19:09,419 the framework of quantum mechanics. Most of physics 521 00:19:09,419 --> 00:19:10,779 is in the, you know, except for gravity 522 00:19:10,779 --> 00:19:12,220 at this point, in the framework of quantum 523 00:19:12,220 --> 00:19:12,720 mechanics. 524 00:19:13,579 --> 00:19:15,419 And and that opens up the possibility that 525 00:19:15,419 --> 00:19:17,740 these same tools that we use to understand 526 00:19:17,740 --> 00:19:19,119 these kind of practical questions, 527 00:19:20,085 --> 00:19:23,105 can be reused in other contexts, right? And 528 00:19:23,125 --> 00:19:26,085 quantum gravity is one context in which we're 529 00:19:26,085 --> 00:19:28,484 seeing that, but there's others too, right? Like 530 00:19:28,484 --> 00:19:30,904 in condensed matter physics, in quantum matter, 531 00:19:31,924 --> 00:19:33,065 we're also seeing, 532 00:19:34,005 --> 00:19:36,500 a lot of these tools from quantum information 533 00:19:36,720 --> 00:19:37,460 being applied, 534 00:19:38,400 --> 00:19:40,420 to to to understand those kind of systems. 535 00:19:41,039 --> 00:19:42,480 And and do you think I mean, has 536 00:19:42,480 --> 00:19:43,700 it, you know, the 537 00:19:44,080 --> 00:19:46,580 boom, well, for lack of a better word, 538 00:19:46,960 --> 00:19:47,860 in in 539 00:19:48,174 --> 00:19:50,654 quantum information research and, you know, the real 540 00:19:50,654 --> 00:19:52,815 depth of understanding that physicists are 541 00:19:53,454 --> 00:19:54,815 have developed. Is that, 542 00:19:55,934 --> 00:19:58,654 I mean, is that something that's, I suppose, 543 00:19:58,654 --> 00:20:00,414 moving outside? I mean, it sounds like it's 544 00:20:00,414 --> 00:20:03,214 moving outside of the quantum information community and 545 00:20:03,214 --> 00:20:03,714 benefiting, 546 00:20:04,390 --> 00:20:06,230 well, you know, people like yourself who are 547 00:20:06,230 --> 00:20:08,549 interested in gravity and people who are interested 548 00:20:08,549 --> 00:20:11,509 in lots of other different kinds of physics. 549 00:20:11,509 --> 00:20:13,190 I'm has it been a I mean, it 550 00:20:13,190 --> 00:20:14,970 sounds like it's been a really positive, 551 00:20:15,349 --> 00:20:17,429 or it's had a very positive impact on 552 00:20:17,429 --> 00:20:19,825 the physics community over the last, I don't 553 00:20:19,825 --> 00:20:22,225 know, twenty, twenty five years. Yeah. I I 554 00:20:22,225 --> 00:20:23,985 certainly think so, and it's certainly up something 555 00:20:23,985 --> 00:20:24,945 I'm excited about. 556 00:20:25,505 --> 00:20:26,805 You know, I think that 557 00:20:27,424 --> 00:20:29,045 to to me, it's a whole different 558 00:20:29,585 --> 00:20:32,099 starting point for understanding quantum mechanics. Like, 559 00:20:32,660 --> 00:20:35,000 when we teach quantum mechanics in undergrad, 560 00:20:36,099 --> 00:20:37,799 we teach it in the context, 561 00:20:38,179 --> 00:20:39,460 at least traditionally, we teach it in the 562 00:20:39,460 --> 00:20:41,140 context that it was developed, which is in 563 00:20:41,140 --> 00:20:43,319 the context of, like, atomic physics. 564 00:20:43,700 --> 00:20:45,859 But quantum mechanics is something much, much more 565 00:20:45,859 --> 00:20:47,799 general than atomic physics, 566 00:20:48,595 --> 00:20:49,095 And 567 00:20:49,875 --> 00:20:51,654 quantum information gives you, 568 00:20:52,115 --> 00:20:53,794 you know, a different lens, a different set 569 00:20:53,794 --> 00:20:56,434 of examples and starting points for thinking about 570 00:20:56,434 --> 00:20:57,255 quantum mechanics. 571 00:20:57,954 --> 00:20:58,434 And, 572 00:20:59,634 --> 00:21:01,554 it also gives you a lot simpler context 573 00:21:01,554 --> 00:21:02,294 for understanding 574 00:21:02,799 --> 00:21:04,339 quantum mechanics. Like I think that, 575 00:21:04,720 --> 00:21:06,400 you know, when you solve the hydrogen atom, 576 00:21:06,400 --> 00:21:08,420 that's an excellent thing that everybody should do. 577 00:21:10,320 --> 00:21:11,940 But if you just want to understand 578 00:21:12,720 --> 00:21:14,880 what are the core features of quantum mechanics 579 00:21:14,880 --> 00:21:16,799 that I need to conceptually get my head 580 00:21:16,799 --> 00:21:17,299 around 581 00:21:17,835 --> 00:21:20,634 something like the quantum teleportation protocol. Some of 582 00:21:20,634 --> 00:21:23,194 the basic aspects of quantum information theory can 583 00:21:23,194 --> 00:21:25,194 be a quicker route to to to getting 584 00:21:25,194 --> 00:21:26,815 that understanding, I think. So, 585 00:21:27,835 --> 00:21:29,194 yeah, it's just a really clean way to 586 00:21:29,194 --> 00:21:30,894 understand quantum mechanics, and that 587 00:21:31,549 --> 00:21:33,230 has this knock on effect of of, 588 00:21:33,630 --> 00:21:35,970 coming into all these other areas. I see. 589 00:21:36,190 --> 00:21:38,509 And, you know, just sort of thinking back 590 00:21:38,509 --> 00:21:41,230 to my education in physics, I mean, I'm 591 00:21:41,230 --> 00:21:43,009 guessing, you know, the last time I 592 00:21:43,390 --> 00:21:44,769 took a course in quantum 593 00:21:45,315 --> 00:21:47,494 mechanics would have been sometime in the nineties. 594 00:21:47,714 --> 00:21:49,554 And, you know, it was very much, you 595 00:21:49,554 --> 00:21:51,815 know, the simple harmonic oscillator. 596 00:21:52,194 --> 00:21:54,434 Yep. The hydrogen atom and all that sort 597 00:21:54,434 --> 00:21:55,095 of stuff. 598 00:21:55,875 --> 00:21:56,934 I mean, is 599 00:21:57,679 --> 00:21:58,339 is it 600 00:21:58,720 --> 00:22:01,039 is quantum information taught now? I mean, I 601 00:22:01,039 --> 00:22:03,539 know that I don't think you you teach, 602 00:22:03,919 --> 00:22:05,599 do you? Or maybe maybe you do teach. 603 00:22:05,599 --> 00:22:06,740 I I do. You do Waterloo. 604 00:22:07,119 --> 00:22:08,640 I actually, I teach in the the master's 605 00:22:08,640 --> 00:22:10,565 program that we have here at Perimeter. So 606 00:22:10,565 --> 00:22:12,845 we have the Psi one year master's program. 607 00:22:12,845 --> 00:22:14,845 Right. And do do you teach Yeah. I 608 00:22:14,845 --> 00:22:17,325 teach quantum information there, actually. Right. I see. 609 00:22:17,325 --> 00:22:19,265 Yeah. Okay. And is it, 610 00:22:20,924 --> 00:22:22,845 I mean, do or, you know, sort of 611 00:22:22,845 --> 00:22:25,890 early career well, master's students, so they do 612 00:22:25,890 --> 00:22:27,349 they find it really fascinating? 613 00:22:27,730 --> 00:22:29,650 I mean, more fascinating than this than the 614 00:22:29,650 --> 00:22:31,029 simple harmonic oscillator. 615 00:22:31,490 --> 00:22:33,910 Yeah. I mean, I think it's it's a 616 00:22:34,849 --> 00:22:37,190 it's a quick route to getting people excited 617 00:22:37,250 --> 00:22:37,664 about 618 00:22:38,225 --> 00:22:40,325 physics and about quantum mechanics. And, 619 00:22:41,345 --> 00:22:42,945 I definitely see a lot of excitement from 620 00:22:42,945 --> 00:22:44,705 my students and a lot of a lot 621 00:22:44,705 --> 00:22:47,345 of interest, like, from multiple different fields. You 622 00:22:47,345 --> 00:22:49,345 know? I don't know. They're interested in gravity. 623 00:22:49,345 --> 00:22:51,279 They're interested in condensed matter, but they wanna 624 00:22:51,279 --> 00:22:53,039 learn a little bit of quantum information as 625 00:22:53,039 --> 00:22:55,059 well. They've heard that it's that it's useful. 626 00:22:56,640 --> 00:22:57,839 Yeah. So you're starting to see a lot 627 00:22:57,839 --> 00:22:59,680 of that. And then there's kind of a 628 00:22:59,680 --> 00:23:01,359 whole other set of people that are interest 629 00:23:01,440 --> 00:23:04,079 interested in or excited about quantum information because 630 00:23:04,079 --> 00:23:06,714 of its applications. Right? Because they're excited about 631 00:23:06,714 --> 00:23:10,634 quantum computing or quantum communication or these sort 632 00:23:10,634 --> 00:23:12,954 of practical things that could happen down the 633 00:23:12,954 --> 00:23:13,454 road. 634 00:23:14,474 --> 00:23:16,714 Yeah. I mean, I I've I've I've just 635 00:23:16,714 --> 00:23:17,695 amazed that 636 00:23:18,240 --> 00:23:21,299 quantum well, I suppose quantum computation, technology, 637 00:23:22,079 --> 00:23:24,799 information, you know, the, it it seems like 638 00:23:24,799 --> 00:23:25,700 it's it's a 639 00:23:26,400 --> 00:23:27,839 I don't think it's wrong to call it 640 00:23:27,839 --> 00:23:30,079 a revolution really in in sort of our 641 00:23:30,079 --> 00:23:30,579 understanding 642 00:23:30,880 --> 00:23:33,414 of of the quantum world. It's, you know, 643 00:23:33,414 --> 00:23:34,855 I think it's a really good time to 644 00:23:34,855 --> 00:23:35,595 be a physicist. 645 00:23:36,535 --> 00:23:37,734 I I think so. I think it's a 646 00:23:37,734 --> 00:23:40,474 very exciting field right now. Well, that's great, 647 00:23:40,855 --> 00:23:42,615 Alex. Thanks so much for coming on the 648 00:23:42,615 --> 00:23:44,394 podcast, and hopefully we've encouraged 649 00:23:44,775 --> 00:23:48,000 some listeners to perhaps look into the intersection 650 00:23:48,000 --> 00:23:50,740 between quantum gravity and, quantum information. 651 00:23:51,359 --> 00:23:52,820 Great. Well, thanks for having me. 652 00:24:00,434 --> 00:24:03,234 That was Alex May in a conversation I 653 00:24:03,234 --> 00:24:07,014 recorded at the Perimeter Institute for Theoretical Physics. 654 00:24:07,554 --> 00:24:10,994 Thanks to Alex for a fascinating chat about 655 00:24:10,994 --> 00:24:12,054 all things quantum, 656 00:24:12,755 --> 00:24:14,774 and thanks to you for listening. 657 00:24:15,640 --> 00:24:18,359 We'll be back again next week. I'm Hamish 658 00:24:18,359 --> 00:24:18,859 Johnston, 659 00:24:19,160 --> 00:24:21,740 and our producer is Fred Isles.