Quarks and qubits: how quantum computing could transform particle physics

WEBVTT
1
00:00:07.679 --> 00:00:10.880
- Hello, and welcome to the Physics World weekly
2
00:00:10.880 --> 00:00:11.380
- podcast,
3
00:00:11.839 --> 00:00:14.740
- which is supported by American Elements.
4
00:00:15.824 --> 00:00:20.244
- Simulating quantum systems is something that classical computers
5
00:00:20.785 --> 00:00:21.765
- struggle with.
6
00:00:22.464 --> 00:00:23.204
- Not surprisingly,
7
00:00:23.984 --> 00:00:26.864
- quantum computers are expected to do a much
8
00:00:26.864 --> 00:00:27.765
- better job,
9
00:00:28.289 --> 00:00:30.629
- particularly when a quantum computer's
10
00:00:30.929 --> 00:00:31.429
- architecture
11
00:00:31.809 --> 00:00:35.170
- is designed to solve a specific type of
12
00:00:35.170 --> 00:00:36.070
- physics problem.
13
00:00:37.250 --> 00:00:39.829
- My guest in this episode of the Physics
14
00:00:39.890 --> 00:00:41.189
- World Weekly podcast
15
00:00:41.649 --> 00:00:42.869
- is Ross Jenkinson
16
00:00:43.505 --> 00:00:44.405
- of The UK's
17
00:00:44.864 --> 00:00:46.164
- University of Manchester.
18
00:00:46.945 --> 00:00:49.604
- He talks about the challenges and rewards
19
00:00:50.064 --> 00:00:51.844
- of using quantum computers
20
00:00:52.225 --> 00:00:53.604
- in particle physics,
21
00:00:54.384 --> 00:00:56.164
- a field where classical
22
00:00:56.545 --> 00:00:57.045
- supercomputers
23
00:00:57.920 --> 00:00:58.579
- can struggle
24
00:00:58.960 --> 00:01:01.059
- to simulate simple systems.
25
00:01:02.159 --> 00:01:02.979
- That conversation
26
00:01:03.439 --> 00:01:07.219
- is coming up after this message from American
27
00:01:07.439 --> 00:01:07.939
- Elements.
28
00:01:09.854 --> 00:01:12.515
- This podcast is brought to you by American
29
00:01:12.814 --> 00:01:13.314
- Elements,
30
00:01:13.935 --> 00:01:14.994
- the world's leading
31
00:01:15.454 --> 00:01:15.954
- manufacturer
32
00:01:16.494 --> 00:01:18.354
- of engineered and advanced
33
00:01:18.655 --> 00:01:19.155
- materials.
34
00:01:19.935 --> 00:01:23.155
- With a catalog of over 35,000
35
00:01:23.454 --> 00:01:23.954
- products
36
00:01:24.480 --> 00:01:28.260
- available in both industrial bulk and laboratory
37
00:01:28.719 --> 00:01:29.219
- quantities,
38
00:01:29.920 --> 00:01:33.280
- American Elements is the largest supplier of its
39
00:01:33.280 --> 00:01:33.780
- kind.
40
00:01:34.560 --> 00:01:37.534
- For more than twenty five years, its research
41
00:01:37.594 --> 00:01:38.334
- and development
42
00:01:38.715 --> 00:01:39.215
- programs
43
00:01:39.515 --> 00:01:41.055
- have been a vital resource
44
00:01:41.355 --> 00:01:42.174
- for innovation
45
00:01:42.715 --> 00:01:43.694
- across corporate,
46
00:01:44.155 --> 00:01:44.655
- government,
47
00:01:45.034 --> 00:01:46.655
- and academic sectors.
48
00:01:47.435 --> 00:01:50.174
- The company's ability to scale laboratory
49
00:01:50.635 --> 00:01:51.135
- breakthroughs
50
00:01:51.609 --> 00:01:53.149
- to industrial production
51
00:01:53.530 --> 00:01:56.109
- has contributed to many of the most significant
52
00:01:56.729 --> 00:01:57.229
- technological
53
00:01:57.689 --> 00:01:58.189
- advancements
54
00:01:58.649 --> 00:02:00.189
- since 1990,
55
00:02:00.810 --> 00:02:02.509
- including LED lighting,
56
00:02:02.890 --> 00:02:03.390
- smartphones,
57
00:02:03.929 --> 00:02:05.310
- and electric vehicles.
58
00:02:06.045 --> 00:02:10.384
- To learn more, visit americanelements.com.
59
00:02:11.085 --> 00:02:12.305
- American Elements,
60
00:02:12.925 --> 00:02:14.064
- now invent.
61
00:02:22.610 --> 00:02:24.550
- Hi, Ross. Welcome to the podcast.
62
00:02:25.409 --> 00:02:26.849
- Hi, Hamish. Thank you very much for having
63
00:02:26.849 --> 00:02:27.349
- me.
64
00:02:27.730 --> 00:02:30.290
- Yeah. I'm really looking forward to talking about,
65
00:02:30.610 --> 00:02:32.550
- applications for quantum computing
66
00:02:33.090 --> 00:02:35.990
- in particle physics and, beyond.
67
00:02:36.305 --> 00:02:36.805
- So
68
00:02:37.105 --> 00:02:39.344
- maybe we could start off with, sort of
69
00:02:39.344 --> 00:02:40.485
- a basic question.
70
00:02:41.025 --> 00:02:43.525
- Why are quantum computers useful
71
00:02:43.905 --> 00:02:44.724
- for simulating
72
00:02:45.025 --> 00:02:46.805
- particle physics collisions?
73
00:02:47.264 --> 00:02:49.205
- And, you know, in comparison to
74
00:02:49.504 --> 00:02:50.004
- conventional
75
00:02:50.385 --> 00:02:50.885
- supercomputers.
76
00:02:52.330 --> 00:02:54.490
- Yeah. It's it's a great question. So but
77
00:02:54.490 --> 00:02:56.509
- first of all, how are quantum computers different?
78
00:02:56.889 --> 00:02:58.889
- So classical computers are kind of written in
79
00:02:58.889 --> 00:03:02.169
- this language of of binary bits. So zeros
80
00:03:02.169 --> 00:03:03.449
- and ones you might have seen in the
81
00:03:03.449 --> 00:03:05.530
- movies. Lots of zeros, lots of ones. But
82
00:03:05.530 --> 00:03:06.030
- crucially,
83
00:03:06.344 --> 00:03:08.905
- it's a zero or a one for any
84
00:03:08.905 --> 00:03:12.185
- given bit. Whereas a quantum computer, because of
85
00:03:12.185 --> 00:03:13.485
- the principle of superposition,
86
00:03:14.425 --> 00:03:16.745
- a quantum bit or a qubit as we
87
00:03:16.745 --> 00:03:18.985
- call it, can be in zero and one
88
00:03:18.985 --> 00:03:20.610
- at the same time. So what that means
89
00:03:20.610 --> 00:03:22.550
- is that we can evolve two possibilities
90
00:03:23.009 --> 00:03:25.889
- at once. And if you have two qubits,
91
00:03:25.889 --> 00:03:28.870
- then there's four possibilities. You have zero zero,
92
00:03:28.930 --> 00:03:31.409
- one one, zero one, and one zero. So
93
00:03:31.409 --> 00:03:32.469
- you have four possibilities
94
00:03:32.930 --> 00:03:34.229
- that you can evolve simultaneously.
95
00:03:34.844 --> 00:03:37.085
- And, actually, as you keep growing this number
96
00:03:37.085 --> 00:03:39.185
- of qubits, so you have n qubits,
97
00:03:39.965 --> 00:03:42.044
- then that scales as two to the power
98
00:03:42.044 --> 00:03:45.264
- of n. So that's mathematically, that's an exponential.
99
00:03:45.564 --> 00:03:47.324
- So when we say it grows exponentially, we
100
00:03:47.324 --> 00:03:49.610
- really we're not saying that colloquially. We mean
101
00:03:49.610 --> 00:03:52.030
- it really does mathematically grow exponentially.
102
00:03:52.569 --> 00:03:54.909
- The number of possibilities that you can simulate
103
00:03:55.290 --> 00:03:57.450
- and evolve at the same time. So this
104
00:03:57.450 --> 00:03:59.129
- is where a lot of the power of
105
00:03:59.129 --> 00:04:00.830
- quantum computing comes from.
106
00:04:01.129 --> 00:04:03.465
- And the reason why it's particularly good
107
00:04:03.864 --> 00:04:04.444
- at simulating
108
00:04:05.064 --> 00:04:07.724
- quantum field theories or or quantum mechanical systems
109
00:04:08.264 --> 00:04:09.004
- is because
110
00:04:09.384 --> 00:04:12.185
- when you have some quantum mechanical system, you
111
00:04:12.185 --> 00:04:14.205
- may have heard that things can happen simultaneously
112
00:04:14.504 --> 00:04:16.120
- to a particle. If it wants to go
113
00:04:16.120 --> 00:04:18.199
- from a to b, it might take one
114
00:04:18.199 --> 00:04:19.479
- path, but it might take a different one
115
00:04:19.479 --> 00:04:21.560
- and a different one. And actually what quantum
116
00:04:21.560 --> 00:04:23.079
- mechanics says is that it takes all of
117
00:04:23.079 --> 00:04:24.459
- these paths simultaneously.
118
00:04:25.240 --> 00:04:27.639
- And if something has a certain energy level,
119
00:04:27.639 --> 00:04:29.319
- it can be in multiple energy levels at
120
00:04:29.319 --> 00:04:31.125
- the same time. So when we start doing
121
00:04:31.125 --> 00:04:32.504
- quantum mechanics calculations,
122
00:04:33.365 --> 00:04:36.404
- you very quickly realize that this system size
123
00:04:36.404 --> 00:04:37.705
- called the Hilbert space
124
00:04:38.085 --> 00:04:41.285
- grows exponentially as well. So it's really, really
125
00:04:41.285 --> 00:04:43.064
- difficult for a classical computer
126
00:04:43.444 --> 00:04:46.459
- to simulate these things. Whereas, as I was
127
00:04:46.459 --> 00:04:48.539
- just saying, this is the natural language of
128
00:04:48.539 --> 00:04:50.539
- a quantum computer. It can simulate these things
129
00:04:50.539 --> 00:04:52.800
- in exactly the same way, also grows exponentially.
130
00:04:53.180 --> 00:04:54.699
- So they're really good. They're kind of a
131
00:04:54.699 --> 00:04:57.579
- natural way to simulate quantum mechanics. Perhaps that's
132
00:04:57.579 --> 00:05:00.394
- unsurprising that a quantum computer is really good
133
00:05:00.394 --> 00:05:01.134
- at simulating
134
00:05:01.754 --> 00:05:02.735
- quantum physics.
135
00:05:03.194 --> 00:05:05.355
- So that's the goal. That's what we're trying
136
00:05:05.355 --> 00:05:08.074
- to we're trying to do with using quantum
137
00:05:08.074 --> 00:05:09.134
- computers. Yeah.
138
00:05:10.074 --> 00:05:12.475
- And and what's the the the state of
139
00:05:12.475 --> 00:05:14.394
- the art at the moment? So, you know,
140
00:05:14.394 --> 00:05:16.550
- quantum computing is a fairly
141
00:05:17.330 --> 00:05:17.990
- new technology.
142
00:05:18.689 --> 00:05:21.350
- Are the the quantum processors that are available
143
00:05:21.490 --> 00:05:21.990
- today,
144
00:05:22.770 --> 00:05:24.689
- are they up for the job? Are they
145
00:05:24.689 --> 00:05:25.589
- able to,
146
00:05:26.610 --> 00:05:28.870
- to sim to simulate meaningful
147
00:05:29.595 --> 00:05:32.314
- particle physics systems, or do we still have
148
00:05:32.314 --> 00:05:33.295
- a way to go,
149
00:05:34.074 --> 00:05:35.194
- in terms of getting,
150
00:05:35.675 --> 00:05:36.814
- practical results
151
00:05:37.194 --> 00:05:39.194
- out of a quantum computer when it comes
152
00:05:39.194 --> 00:05:40.254
- to particle physics?
153
00:05:41.675 --> 00:05:43.595
- Yeah. So there's kind of a few different
154
00:05:43.595 --> 00:05:44.639
- things there. I mean, so
155
00:05:45.199 --> 00:05:46.720
- the current state of the art will depend
156
00:05:46.720 --> 00:05:49.040
- who you ask. Specifically, it depends which company
157
00:05:49.040 --> 00:05:51.040
- you ask. But if you wanted just to
158
00:05:51.040 --> 00:05:52.960
- get a large array of cubits, I think
159
00:05:52.960 --> 00:05:55.280
- there's a a company that has done 6,000
160
00:05:55.280 --> 00:05:56.800
- cubits all in a all in a large
161
00:05:56.800 --> 00:05:58.584
- collection, and that's all well and good, but
162
00:05:58.584 --> 00:06:00.345
- they're not interacting. You can't use them to
163
00:06:00.345 --> 00:06:02.845
- calculate. In terms of a benchmark calculation,
164
00:06:03.944 --> 00:06:06.264
- so, yeah, chips are already being developed. You
165
00:06:06.264 --> 00:06:08.264
- have Google who have developed a chip that
166
00:06:08.264 --> 00:06:11.004
- they've called Willow, which is a 105
167
00:06:11.064 --> 00:06:11.564
- qubits.
168
00:06:12.600 --> 00:06:14.439
- So that's pretty powerful. I mean, if you
169
00:06:14.439 --> 00:06:16.520
- think about that in terms of classical bits,
170
00:06:16.520 --> 00:06:18.360
- that's not very lot at all. A 105
171
00:06:18.360 --> 00:06:18.860
- bits
172
00:06:19.240 --> 00:06:21.240
- of information isn't a lot. But when you
173
00:06:21.240 --> 00:06:23.080
- do two to the power of a 105
174
00:06:23.080 --> 00:06:24.620
- and think about the kind of possibilities
175
00:06:25.175 --> 00:06:27.495
- there, that is actually really powerful. In fact,
176
00:06:27.495 --> 00:06:28.555
- they did a calculation,
177
00:06:29.095 --> 00:06:30.455
- and this is kind of cheating a little
178
00:06:30.455 --> 00:06:32.375
- bit because they deliberately built the chip to
179
00:06:32.375 --> 00:06:34.455
- do the specific calculation. So I don't want
180
00:06:34.455 --> 00:06:36.375
- to oversell it, but it was built to
181
00:06:36.375 --> 00:06:38.055
- do a calculation, and it did it in
182
00:06:38.055 --> 00:06:40.910
- five minutes. And they calculated that the world's
183
00:06:40.910 --> 00:06:43.970
- largest, most powerful classical computer
184
00:06:44.590 --> 00:06:46.529
- would have done it in ten septillion
185
00:06:46.830 --> 00:06:47.330
- years.
186
00:06:47.790 --> 00:06:49.949
- So it would have taken a a huge
187
00:06:49.949 --> 00:06:52.185
- amount of time for a normal computer to
188
00:06:52.185 --> 00:06:53.165
- do the same calculation.
189
00:06:53.544 --> 00:06:56.824
- So they are already doing really powerful, interesting
190
00:06:56.824 --> 00:06:57.324
- calculations
191
00:06:58.024 --> 00:07:00.365
- using quantum computing chips. But how
192
00:07:00.904 --> 00:07:03.870
- relevant is that for the particle physics stuff?
193
00:07:04.269 --> 00:07:05.629
- Well, we're still a while off. I I
194
00:07:05.629 --> 00:07:07.790
- would say from both a theoretical and an
195
00:07:07.790 --> 00:07:09.470
- engineering point of view, we're kind of in
196
00:07:09.470 --> 00:07:12.449
- the foothills of this really exciting journey.
197
00:07:13.069 --> 00:07:14.449
- We're we're starting to do
198
00:07:14.750 --> 00:07:15.250
- benchmark
199
00:07:15.870 --> 00:07:17.009
- example calculations,
200
00:07:17.794 --> 00:07:19.074
- But in order to actually get them to
201
00:07:19.074 --> 00:07:21.254
- simulate real particle interactions,
202
00:07:21.714 --> 00:07:23.495
- that's quite difficult. And, actually,
203
00:07:24.514 --> 00:07:26.834
- the classical methods we have are really powerful.
204
00:07:26.834 --> 00:07:29.154
- We've been we've been developing them for for
205
00:07:29.154 --> 00:07:31.154
- decades. I say we have been in development
206
00:07:31.154 --> 00:07:32.399
- since before I was born.
207
00:07:33.360 --> 00:07:35.620
- So really, really well tested stuff. In fact,
208
00:07:36.160 --> 00:07:37.060
- quantum electrodynamics,
209
00:07:37.519 --> 00:07:38.819
- which is one of the
210
00:07:39.360 --> 00:07:42.240
- basically applications of our of our quantum mechanical
211
00:07:42.240 --> 00:07:42.740
- methods
212
00:07:43.279 --> 00:07:45.539
- is one of the most well experimentally
213
00:07:45.919 --> 00:07:46.979
- verified methods
214
00:07:47.345 --> 00:07:50.564
- in all of science. It's it's experimentally verified
215
00:07:50.865 --> 00:07:53.185
- at the Large Hadron Collider to about one
216
00:07:53.185 --> 00:07:54.725
- part in 1,000,000,000,000.
217
00:07:55.024 --> 00:07:56.944
- So that's I mean, just to give some
218
00:07:56.944 --> 00:07:58.004
- scale as to how
219
00:07:58.464 --> 00:08:01.169
- unbelievably accurate that is. That's like measuring the
220
00:08:01.169 --> 00:08:03.649
- length of The United Kingdom from from Lands'
221
00:08:03.649 --> 00:08:04.949
- End, Saviano Groats,
222
00:08:05.329 --> 00:08:07.250
- down to the width of a red blood
223
00:08:07.250 --> 00:08:09.649
- cell. In fact, it's more accurate than that.
224
00:08:09.649 --> 00:08:11.430
- So one part in a 1,000,000,000,000.
225
00:08:11.729 --> 00:08:13.705
- So really, really good methods. And so we
226
00:08:13.705 --> 00:08:15.625
- don't have to just get quantum computing to
227
00:08:15.625 --> 00:08:17.064
- work. We have to get it to be
228
00:08:17.064 --> 00:08:18.685
- even better than that, basically.
229
00:08:19.465 --> 00:08:20.824
- And so this is where that kind of
230
00:08:20.824 --> 00:08:22.045
- power of this simultaneously
231
00:08:22.824 --> 00:08:25.944
- evolving things. And, actually, what classical methods do
232
00:08:25.944 --> 00:08:27.944
- is they kind of do slight approximations because
233
00:08:27.944 --> 00:08:30.420
- they they can't do that. So there's certain
234
00:08:30.420 --> 00:08:32.919
- regimes where they can do calculations very well.
235
00:08:33.059 --> 00:08:35.620
- But to actually evolve a quantum system in
236
00:08:35.620 --> 00:08:37.620
- real time and kind of, like, press play,
237
00:08:37.620 --> 00:08:40.419
- press pause, inspect it, we can't do that.
238
00:08:40.419 --> 00:08:42.360
- Whereas a quantum computer perhaps could.
239
00:08:43.644 --> 00:08:45.184
- And and Ross, you mentioned,
240
00:08:46.524 --> 00:08:48.605
- a a quantum computer that was created to
241
00:08:48.605 --> 00:08:50.304
- solve a specific problem,
242
00:08:50.924 --> 00:08:53.644
- and it did so very well. Is that
243
00:08:53.644 --> 00:08:55.024
- is that sort of the idea
244
00:08:55.404 --> 00:08:58.850
- in how quantum computers would be used, at
245
00:08:58.850 --> 00:09:02.710
- least initially, to to solve particle physics problems?
246
00:09:03.170 --> 00:09:04.230
- The the architecture
247
00:09:04.610 --> 00:09:06.790
- of the quantum computer would be designed
248
00:09:07.250 --> 00:09:08.550
- such that it was
249
00:09:08.930 --> 00:09:10.070
- somehow similar
250
00:09:10.370 --> 00:09:10.870
- to
251
00:09:11.490 --> 00:09:12.629
- a particle collision
252
00:09:13.044 --> 00:09:15.125
- that you were interested in? Is is is
253
00:09:15.125 --> 00:09:17.125
- that one way of, you know, sort of
254
00:09:17.125 --> 00:09:17.625
- accelerating
255
00:09:18.004 --> 00:09:19.845
- the use of of,
256
00:09:20.325 --> 00:09:22.184
- of quantum computers? Actually,
257
00:09:22.565 --> 00:09:23.544
- making the architecture
258
00:09:24.245 --> 00:09:25.384
- fit the problem.
259
00:09:25.850 --> 00:09:27.370
- Yeah. I mean, that's a really, really good
260
00:09:27.370 --> 00:09:28.830
- point. And that that is exactly
261
00:09:29.370 --> 00:09:31.450
- the the way forward, I think. So the
262
00:09:31.450 --> 00:09:32.809
- era that we're in at the moment is
263
00:09:32.809 --> 00:09:35.129
- called the NISQ era, n I s q,
264
00:09:35.129 --> 00:09:38.750
- stands for noisy intermediate scale quantum era.
265
00:09:39.095 --> 00:09:41.254
- So the noisy is really the the the
266
00:09:41.254 --> 00:09:42.695
- main part about that. And what that means
267
00:09:42.695 --> 00:09:44.855
- is that we can't error correct. So we
268
00:09:44.855 --> 00:09:46.535
- can't we take a bunch of qubits and
269
00:09:46.535 --> 00:09:48.315
- they're really susceptible to
270
00:09:48.855 --> 00:09:51.434
- changes because of their interaction with the environment.
271
00:09:51.495 --> 00:09:52.955
- They're really hard to isolate.
272
00:09:53.330 --> 00:09:54.450
- So what we have to do is we
273
00:09:54.450 --> 00:09:55.649
- have to kind of get a group of
274
00:09:55.649 --> 00:09:57.990
- qubits to all fact check each other constantly.
275
00:09:58.450 --> 00:10:00.450
- That's how we do quantum error correction, but
276
00:10:00.450 --> 00:10:02.690
- that is currently the engineering challenge that everyone
277
00:10:02.690 --> 00:10:03.990
- is trying to to overcome.
278
00:10:04.450 --> 00:10:06.049
- So we're kind of in that era at
279
00:10:06.049 --> 00:10:07.794
- the moment, and what that means is that
280
00:10:07.794 --> 00:10:10.595
- we don't have fault tolerant quantum computing, but
281
00:10:10.595 --> 00:10:12.914
- we also don't have we're not really close
282
00:10:12.914 --> 00:10:15.394
- to. We're probably twenty, thirty years away from
283
00:10:15.394 --> 00:10:17.794
- a fully programmable quantum computer. So if you
284
00:10:17.794 --> 00:10:19.519
- think about your laptop, you can do all
285
00:10:19.519 --> 00:10:22.259
- sorts on your laptop. It's it's very programmable.
286
00:10:22.639 --> 00:10:23.139
- Right?
287
00:10:23.679 --> 00:10:26.159
- So because that's so far away, you're exactly
288
00:10:26.159 --> 00:10:28.159
- right. We can instead build devices that are
289
00:10:28.159 --> 00:10:29.699
- kind of purpose built. Imagine
290
00:10:30.000 --> 00:10:32.079
- like a calculator. A calculator is a really
291
00:10:32.079 --> 00:10:34.735
- useful device. A calculator is really good at
292
00:10:34.735 --> 00:10:36.415
- maths, but it's not gonna tell you the
293
00:10:36.415 --> 00:10:38.654
- weather. You know? So if you wanted to
294
00:10:38.654 --> 00:10:40.894
- have a purpose built device, you can exactly
295
00:10:40.894 --> 00:10:43.535
- do that. Firstly, with the architecture, so, yeah,
296
00:10:43.535 --> 00:10:45.054
- so you can you can design it in
297
00:10:45.054 --> 00:10:45.870
- such a way
298
00:10:46.350 --> 00:10:48.750
- using a certain medium that it might be
299
00:10:48.750 --> 00:10:49.809
- specifically good
300
00:10:50.190 --> 00:10:51.629
- at. So, for example, when I talk about
301
00:10:51.629 --> 00:10:53.789
- these qubits, they seem like quite abstract ideas,
302
00:10:53.789 --> 00:10:55.950
- but the actual candidates for qubits are things
303
00:10:55.950 --> 00:10:57.250
- like cold atoms,
304
00:10:57.789 --> 00:10:58.690
- trapped ions,
305
00:10:59.309 --> 00:10:59.809
- photons.
306
00:11:00.355 --> 00:11:02.674
- Each one of them has pros and cons.
307
00:11:02.674 --> 00:11:05.075
- And so for specific calculations, you might want
308
00:11:05.075 --> 00:11:06.215
- to use different ones.
309
00:11:06.595 --> 00:11:08.835
- So there's lots of investment in which one's
310
00:11:08.835 --> 00:11:11.254
- gonna be the best for a fully programmable
311
00:11:11.554 --> 00:11:13.394
- quantum computer, but actually they all have their
312
00:11:13.394 --> 00:11:14.134
- own advantages.
313
00:11:15.300 --> 00:11:16.660
- So yeah. And and one of the things
314
00:11:16.660 --> 00:11:18.519
- that I do in my research is
315
00:11:19.059 --> 00:11:20.660
- I say, well, it's all well and good
316
00:11:20.660 --> 00:11:22.660
- trying to build a quantum computer, but if
317
00:11:22.660 --> 00:11:24.340
- you put one in front of me, the
318
00:11:24.340 --> 00:11:24.840
- world
319
00:11:25.379 --> 00:11:27.884
- at the moment doesn't have a set of
320
00:11:27.884 --> 00:11:29.725
- algorithms to run on it, to actually do
321
00:11:29.725 --> 00:11:31.565
- the stuff that we want to do. So
322
00:11:31.565 --> 00:11:32.784
- I'm coming up with
323
00:11:33.164 --> 00:11:35.644
- architecture in the theoretical sense. I'm coming up
324
00:11:35.644 --> 00:11:38.684
- with circuits and algorithms that we could actually
325
00:11:38.684 --> 00:11:41.230
- put onto a quantum computer to get it
326
00:11:41.230 --> 00:11:42.830
- to do the stuff we want to do.
327
00:11:42.830 --> 00:11:44.590
- And so that's the kind of stuff that
328
00:11:44.590 --> 00:11:45.410
- we have to build
329
00:11:46.110 --> 00:11:49.230
- kind of in parallel to the engineering challenges
330
00:11:49.230 --> 00:11:51.009
- for lots of companies are trying to overcome.
331
00:11:52.190 --> 00:11:54.565
- And and what about the idea of, you
332
00:11:54.565 --> 00:11:56.985
- know, you mentioned that conventional supercomputing
333
00:11:57.365 --> 00:11:58.425
- is very advanced
334
00:11:58.965 --> 00:12:00.985
- when it comes to, understanding
335
00:12:01.445 --> 00:12:04.884
- particle physics or doing simulations on particle physics.
336
00:12:04.884 --> 00:12:06.644
- Is I mean, is part of the way
337
00:12:06.644 --> 00:12:10.090
- forward to to only use the quantum processor
338
00:12:10.790 --> 00:12:12.809
- to do a specific calculation
339
00:12:13.110 --> 00:12:15.930
- that would take ages on the supercomputer,
340
00:12:16.550 --> 00:12:19.190
- and then sort of feed that information back
341
00:12:19.190 --> 00:12:21.590
- into the supercomputer, and back and forth, and
342
00:12:21.590 --> 00:12:23.745
- back and forth. So you would use the
343
00:12:23.745 --> 00:12:24.725
- quantum computer
344
00:12:25.184 --> 00:12:27.684
- as a sort of, well, auxiliary
345
00:12:28.865 --> 00:12:31.664
- processor or something that can do one thing
346
00:12:31.664 --> 00:12:32.404
- very well.
347
00:12:34.225 --> 00:12:36.245
- Yeah. Is that a way forward?
348
00:12:36.669 --> 00:12:38.669
- Yeah. 100%. So it's kind of a hybrid
349
00:12:38.669 --> 00:12:42.210
- computing, part quantum, part classical. That's really important.
350
00:12:42.350 --> 00:12:43.870
- Firstly, because there's a bunch of stuff that
351
00:12:43.870 --> 00:12:45.549
- classical computers are very good at, and we've
352
00:12:45.549 --> 00:12:47.549
- already got them to do. And, actually, the
353
00:12:47.549 --> 00:12:49.149
- quantum computer, we don't need it to do
354
00:12:49.149 --> 00:12:50.904
- and it and actually quite difficult. So for
355
00:12:50.904 --> 00:12:51.965
- example, readout,
356
00:12:52.424 --> 00:12:54.424
- reading out a measurement, we know how to
357
00:12:54.424 --> 00:12:56.345
- do that classically. It might be quite hard
358
00:12:56.345 --> 00:12:58.345
- to do quantum mechanically. So as long as
359
00:12:58.345 --> 00:12:59.945
- we get the kind of hard part of
360
00:12:59.945 --> 00:13:00.605
- the calculation
361
00:13:01.544 --> 00:13:02.365
- kind of bootstrapped
362
00:13:02.709 --> 00:13:04.789
- onto a quantum computer, then that's where the
363
00:13:04.789 --> 00:13:07.830
- real advantage lies. It's also worth saying, again,
364
00:13:07.830 --> 00:13:09.509
- there's a lot of hype and and rightly
365
00:13:09.509 --> 00:13:11.029
- so, and I'm very excited about it. It's
366
00:13:11.029 --> 00:13:12.709
- why I've chosen to research it for my
367
00:13:12.709 --> 00:13:15.909
- my job. Right? But it's important not to
368
00:13:15.909 --> 00:13:16.815
- overstate that
369
00:13:17.294 --> 00:13:21.154
- quantum computers will never completely replace classical computers.
370
00:13:21.615 --> 00:13:22.894
- I don't think we will ever live in
371
00:13:22.894 --> 00:13:25.774
- a world where no one has phones, laptops,
372
00:13:25.774 --> 00:13:28.254
- whatever equivalent there is that's running on this
373
00:13:28.254 --> 00:13:30.914
- kind of classical baseline of digital bits,
374
00:13:31.490 --> 00:13:33.169
- and everything is quantum. I don't think that
375
00:13:33.169 --> 00:13:35.089
- would be the case. I think the most
376
00:13:35.089 --> 00:13:37.169
- optimal way will be a hybrid of the
377
00:13:37.169 --> 00:13:38.549
- two, exactly like you say.
378
00:13:39.490 --> 00:13:41.750
- And and what in terms of,
379
00:13:42.450 --> 00:13:45.169
- sort of general areas of particle physics that
380
00:13:45.169 --> 00:13:48.495
- could benefit from quantum computing. You you mentioned
381
00:13:48.554 --> 00:13:49.054
- quantum
382
00:13:49.595 --> 00:13:50.095
- electrodynamics,
383
00:13:51.595 --> 00:13:53.134
- but then there's quantum chromodynamics,
384
00:13:53.675 --> 00:13:54.415
- which is
385
00:13:54.875 --> 00:13:55.375
- extraordinarily
386
00:13:56.075 --> 00:13:56.575
- difficult
387
00:13:57.115 --> 00:13:59.774
- to to do any calculations, really.
388
00:14:00.419 --> 00:14:02.340
- You know, this is the the the physics
389
00:14:02.340 --> 00:14:03.159
- that describes,
390
00:14:04.019 --> 00:14:07.399
- how quarks behave inside protons and neutrons.
391
00:14:09.339 --> 00:14:12.200
- It that is a very difficult problem, computationally.
392
00:14:13.434 --> 00:14:13.934
- Will
393
00:14:14.394 --> 00:14:16.894
- quantum computing help with that?
394
00:14:17.674 --> 00:14:19.774
- Is it is that sort of a quantum
395
00:14:20.315 --> 00:14:23.995
- computing friendly problem where lots of progress could
396
00:14:23.995 --> 00:14:24.654
- be made?
397
00:14:25.720 --> 00:14:28.300
- Yeah. Absolutely. So for a few different reasons.
398
00:14:28.360 --> 00:14:29.580
- So so firstly,
399
00:14:30.040 --> 00:14:30.540
- quantum
400
00:14:30.920 --> 00:14:31.420
- chromodynamics
401
00:14:32.200 --> 00:14:33.980
- quite often in certain energy limits
402
00:14:34.440 --> 00:14:36.600
- doesn't play well with perturbation theory, which is
403
00:14:36.600 --> 00:14:39.240
- our usual toolbox for quantum mechanics, which basically
404
00:14:39.240 --> 00:14:40.634
- just means that if you have a small
405
00:14:40.634 --> 00:14:42.654
- enough coupling constant, you can
406
00:14:44.554 --> 00:14:48.235
- expand your maths in different terms that are
407
00:14:48.235 --> 00:14:49.615
- in less and less important.
408
00:14:50.074 --> 00:14:52.074
- Whereas in quantum chromodynamics, that's often not the
409
00:14:52.074 --> 00:14:53.274
- case, and so what they do is they
410
00:14:53.274 --> 00:14:55.375
- call they do something called lattice QCD,
411
00:14:56.370 --> 00:14:58.210
- which is really interesting in and of its
412
00:14:58.210 --> 00:15:00.769
- own right and very, very well experimentally tested,
413
00:15:00.769 --> 00:15:01.269
- and
414
00:15:01.649 --> 00:15:03.190
- the theory there is really good.
415
00:15:03.570 --> 00:15:05.090
- But wouldn't it be great if we could
416
00:15:05.090 --> 00:15:07.330
- real time evolve of these these quarks and
417
00:15:07.330 --> 00:15:09.269
- these quantum chromodynamic particles
418
00:15:09.774 --> 00:15:12.414
- and actually inspect it in real time, real
419
00:15:12.414 --> 00:15:14.414
- time quantum field theory. That's the kind of
420
00:15:14.414 --> 00:15:16.254
- the stuff that I'm interested in. And it's
421
00:15:16.254 --> 00:15:18.014
- also worth saying that there's lots of other
422
00:15:18.014 --> 00:15:20.434
- things in quantum chromodynamics that expand
423
00:15:21.054 --> 00:15:22.740
- massively. So, for example, color
424
00:15:23.539 --> 00:15:25.459
- color flow. So color, this red, green, or
425
00:15:25.459 --> 00:15:27.459
- blue, is how we label quarks. Each one
426
00:15:27.459 --> 00:15:29.379
- of them has their own color. It's the
427
00:15:29.379 --> 00:15:30.519
- charge of QCD,
428
00:15:31.139 --> 00:15:32.899
- kind of like how electric charge is the
429
00:15:32.899 --> 00:15:35.299
- charge of QED. Right? So you have this
430
00:15:35.299 --> 00:15:36.039
- this color,
431
00:15:36.375 --> 00:15:37.975
- And the number of color states as as
432
00:15:37.975 --> 00:15:40.934
- as your your your gluons and your quarks
433
00:15:40.934 --> 00:15:43.174
- and all of these, they explode in these
434
00:15:43.174 --> 00:15:43.674
- jets.
435
00:15:44.134 --> 00:15:46.695
- That grows factorially. So it's actually even worse
436
00:15:46.695 --> 00:15:49.195
- than exponentially. So it's it's impossible
437
00:15:49.575 --> 00:15:50.879
- impossible to do
438
00:15:51.679 --> 00:15:53.220
- on a classical computer
439
00:15:53.600 --> 00:15:56.080
- a 100% accurately. Again, there's a lot of
440
00:15:56.080 --> 00:15:58.240
- really good work that's being done to try
441
00:15:58.240 --> 00:16:01.039
- and model these parton showers. But if we
442
00:16:01.039 --> 00:16:03.759
- can get a a quantum computer to attack
443
00:16:03.759 --> 00:16:05.279
- this problem, I think it would be really,
444
00:16:05.279 --> 00:16:06.225
- really useful. Yeah?
445
00:16:07.504 --> 00:16:11.105
- And and another, sort of computational technique that,
446
00:16:12.144 --> 00:16:14.704
- I suppose is of great interest to,
447
00:16:15.105 --> 00:16:16.884
- particle physicists is
448
00:16:17.264 --> 00:16:19.250
- artificial intelligence. Can
449
00:16:20.350 --> 00:16:22.289
- you talk a bit about how,
450
00:16:22.669 --> 00:16:23.889
- artificial intelligence
451
00:16:24.990 --> 00:16:26.990
- is is being used and could be used
452
00:16:26.990 --> 00:16:27.490
- by,
453
00:16:28.190 --> 00:16:29.169
- particle physicists,
454
00:16:29.629 --> 00:16:31.730
- you know, maybe in the context of quantum
455
00:16:31.789 --> 00:16:32.289
- computing?
456
00:16:33.195 --> 00:16:35.995
- Yeah. Absolutely. I mean, firstly, just at the
457
00:16:35.995 --> 00:16:37.915
- the kind of easy level of, like, how
458
00:16:37.915 --> 00:16:39.355
- do I use AI on a day to
459
00:16:39.355 --> 00:16:41.055
- day basis and the way that it's transformed
460
00:16:41.115 --> 00:16:43.355
- my life. I mean, throughout my PhD, I
461
00:16:43.355 --> 00:16:45.675
- didn't have access to AI. And so when
462
00:16:45.675 --> 00:16:48.095
- I coded something that would be time consuming
463
00:16:48.440 --> 00:16:50.440
- or doing a literature review, obviously, I still
464
00:16:50.440 --> 00:16:51.959
- go away and read lots of papers. But
465
00:16:51.959 --> 00:16:54.220
- finding papers, I would essentially just be using
466
00:16:54.279 --> 00:16:55.980
- Google or looking in journals.
467
00:16:56.519 --> 00:16:58.519
- AI right now is really useful for physicists
468
00:16:58.519 --> 00:17:01.720
- across the world for accelerating the coding process.
469
00:17:01.720 --> 00:17:03.399
- You still have to double check it because
470
00:17:03.399 --> 00:17:06.274
- it can often be be incorrect, but also
471
00:17:06.654 --> 00:17:08.174
- giving you a group of papers to go
472
00:17:08.174 --> 00:17:09.855
- away and read, and you can decide whether
473
00:17:09.855 --> 00:17:11.694
- they're relevant. And often, it does a pretty
474
00:17:11.694 --> 00:17:13.454
- good job of giving you a batch of
475
00:17:13.454 --> 00:17:16.335
- papers to familiarize yourself with the field. So
476
00:17:16.335 --> 00:17:19.049
- that's kind of the the low entry level
477
00:17:19.049 --> 00:17:20.970
- way that AIB is used by me at
478
00:17:20.970 --> 00:17:22.809
- least on a day to day basis. They're
479
00:17:22.809 --> 00:17:24.809
- kind of like blue skies idea, the stuff
480
00:17:24.809 --> 00:17:27.609
- that I'm also working on in terms of
481
00:17:27.609 --> 00:17:29.150
- AI and machine learning.
482
00:17:29.734 --> 00:17:32.234
- Is can we apply these to kind
483
00:17:33.575 --> 00:17:35.894
- of fit quantum algorithms in a way that
484
00:17:35.894 --> 00:17:38.234
- often quantum mechanics is is really counterintuitive.
485
00:17:39.174 --> 00:17:41.654
- So maybe we're thinking about it in the
486
00:17:41.654 --> 00:17:43.529
- wrong way when we try and come up
487
00:17:43.529 --> 00:17:46.269
- with quantum circuits. In fact, it is very
488
00:17:46.730 --> 00:17:49.049
- common that someone comes up with a quantum
489
00:17:49.049 --> 00:17:51.869
- algorithm that is essentially just a classical algorithm,
490
00:17:52.170 --> 00:17:54.090
- but written in the language of qubits and
491
00:17:54.090 --> 00:17:54.990
- actually isn't
492
00:17:55.304 --> 00:17:58.504
- using things like superposition and entanglement to actually
493
00:17:58.504 --> 00:18:00.125
- gain any kind of advantage.
494
00:18:00.504 --> 00:18:03.404
- And so that circuit is never gonna actually
495
00:18:03.704 --> 00:18:05.565
- be better than a classical computer.
496
00:18:05.865 --> 00:18:06.365
- So
497
00:18:06.744 --> 00:18:07.884
- maybe AI
498
00:18:08.440 --> 00:18:10.200
- can work to kind of come up with
499
00:18:10.200 --> 00:18:12.119
- new quantum circuits. And in fact, that is
500
00:18:12.119 --> 00:18:14.200
- being done. There are research groups around the
501
00:18:14.200 --> 00:18:16.119
- world that are kind of trying to come
502
00:18:16.119 --> 00:18:18.359
- up with almost a large language model, but
503
00:18:18.359 --> 00:18:19.740
- for quantum algorithms.
504
00:18:20.085 --> 00:18:22.404
- So that's a really interesting and a niche
505
00:18:22.404 --> 00:18:23.704
- area that that
506
00:18:24.085 --> 00:18:26.804
- excites me a lot. But also machine learning
507
00:18:26.804 --> 00:18:28.005
- says something that I want to try and
508
00:18:28.005 --> 00:18:28.744
- do is
509
00:18:29.125 --> 00:18:31.284
- when we evolve these quantum systems and there's
510
00:18:31.284 --> 00:18:33.065
- there's infinite number of possibilities,
511
00:18:34.085 --> 00:18:35.784
- and formally, you have to
512
00:18:36.140 --> 00:18:38.460
- sum up every single possibility. So how do
513
00:18:38.460 --> 00:18:39.980
- you do an infinite sum? Well, it's very
514
00:18:39.980 --> 00:18:40.480
- difficult.
515
00:18:40.940 --> 00:18:42.080
- And so often,
516
00:18:42.460 --> 00:18:45.259
- computationally, that's impossible. So you have to come
517
00:18:45.259 --> 00:18:47.900
- up with tricks and you have to think,
518
00:18:47.900 --> 00:18:50.140
- okay. Well, which paths are actually important and
519
00:18:50.140 --> 00:18:51.440
- which ones aren't important?
520
00:18:51.904 --> 00:18:53.664
- Or maybe a machine learning model could learn
521
00:18:53.664 --> 00:18:55.585
- that for us. And maybe in the process
522
00:18:55.585 --> 00:18:57.825
- of doing that, it will reveal something about
523
00:18:57.825 --> 00:19:00.544
- quantum mechanics that we don't yet know. So
524
00:19:00.544 --> 00:19:01.904
- these are the kind of ways I want
525
00:19:01.904 --> 00:19:04.164
- to apply AI and machine learning.
526
00:19:05.230 --> 00:19:07.089
- And what what about your colleagues,
527
00:19:07.549 --> 00:19:10.429
- you know, who run particle physics experiments? I
528
00:19:10.429 --> 00:19:11.569
- would imagine that
529
00:19:12.029 --> 00:19:13.490
- AI and machine learning
530
00:19:14.109 --> 00:19:15.889
- is becoming really important
531
00:19:16.349 --> 00:19:19.125
- in in helping them deal with the the
532
00:19:19.125 --> 00:19:21.605
- sort of deluge of data that comes out
533
00:19:21.605 --> 00:19:21.845
- of,
534
00:19:22.724 --> 00:19:25.684
- an experiment on the Large Hadron Collider, for
535
00:19:25.684 --> 00:19:26.184
- example?
536
00:19:26.884 --> 00:19:29.125
- Yeah. I mean, this is, again, great question,
537
00:19:29.125 --> 00:19:31.525
- brilliant point, and and actually quite relevant to
538
00:19:31.525 --> 00:19:33.900
- another thing that I'm working on, actually. So,
539
00:19:34.279 --> 00:19:34.779
- basically,
540
00:19:35.799 --> 00:19:37.559
- Abelard, Hadron Collider, for those who don't know,
541
00:19:37.559 --> 00:19:40.759
- it it's billions of particle interactions per second
542
00:19:40.759 --> 00:19:43.079
- when it when it's running. So these datasets
543
00:19:43.079 --> 00:19:44.920
- are some of the biggest datasets in the
544
00:19:44.920 --> 00:19:47.465
- world, and it's not just one bit of
545
00:19:47.465 --> 00:19:49.945
- data for each particle. You you get its
546
00:19:49.945 --> 00:19:51.705
- momentum. You can get scattering angles. You get
547
00:19:51.705 --> 00:19:53.865
- all all sorts of things. So this dataset
548
00:19:53.865 --> 00:19:55.404
- is really massive. And so
549
00:19:55.865 --> 00:19:58.365
- scouring through it and trying to find interesting
550
00:19:58.585 --> 00:20:00.765
- bumps in the data that you weren't predicting
551
00:20:00.825 --> 00:20:02.160
- that might reveal new physics,
552
00:20:02.720 --> 00:20:04.640
- That's a really difficult thing. Again, it has
553
00:20:04.640 --> 00:20:06.080
- been done very well. I mean, the Higgs
554
00:20:06.080 --> 00:20:09.539
- particle in 2012 was discovered using classical techniques.
555
00:20:10.000 --> 00:20:10.500
- So
556
00:20:11.039 --> 00:20:11.539
- it's
557
00:20:11.840 --> 00:20:12.740
- doing really well,
558
00:20:13.119 --> 00:20:15.855
- but machine learning absolutely is being used
559
00:20:16.815 --> 00:20:18.595
- to essentially try and spot patterns
560
00:20:18.974 --> 00:20:20.275
- in the data
561
00:20:20.654 --> 00:20:22.894
- in a much quicker, much more efficient way,
562
00:20:22.894 --> 00:20:24.755
- and perhaps in a in a novel way
563
00:20:24.815 --> 00:20:27.134
- using techniques that we might not have thought
564
00:20:27.134 --> 00:20:27.634
- of
565
00:20:27.980 --> 00:20:28.720
- in order
566
00:20:29.019 --> 00:20:29.680
- to discover
567
00:20:30.140 --> 00:20:32.000
- new particles or new structures
568
00:20:32.380 --> 00:20:34.700
- in the standard model. So, for example, something
569
00:20:34.700 --> 00:20:36.859
- I'm working on is, can we map this
570
00:20:36.859 --> 00:20:38.859
- to a quantum computer? So can we take
571
00:20:38.859 --> 00:20:39.519
- the final
572
00:20:39.900 --> 00:20:41.184
- state particles,
573
00:20:41.484 --> 00:20:42.545
- take their momenta,
574
00:20:43.404 --> 00:20:45.105
- map it onto a bunch of qubits,
575
00:20:45.724 --> 00:20:47.884
- and then entangle those qubits in such a
576
00:20:47.884 --> 00:20:50.684
- way that we try to mirror some of
577
00:20:50.684 --> 00:20:53.325
- the correlations that you might expect between these
578
00:20:53.325 --> 00:20:54.384
- final state particles.
579
00:20:55.250 --> 00:20:56.309
- So we entangle
580
00:20:57.089 --> 00:20:59.809
- pairwise entangle the final state particles, and then
581
00:20:59.809 --> 00:21:02.529
- we run a machine learning code on this
582
00:21:02.529 --> 00:21:03.589
- network of qubits.
583
00:21:03.970 --> 00:21:04.470
- And
584
00:21:04.849 --> 00:21:07.809
- can this quantum computing and machine learning work
585
00:21:07.809 --> 00:21:10.595
- together to potentially give us an advantage over
586
00:21:10.595 --> 00:21:12.535
- traditional machine learning methods.
587
00:21:12.994 --> 00:21:15.554
- So some really exciting stuff there, but absolutely
588
00:21:15.554 --> 00:21:17.494
- machine learning and AI is being used
589
00:21:17.954 --> 00:21:21.234
- and being used increasingly more in particle physics
590
00:21:21.234 --> 00:21:22.595
- and a lot of my colleagues at the
591
00:21:22.595 --> 00:21:23.095
- LHC.
592
00:21:24.710 --> 00:21:25.909
- So it sounds like,
593
00:21:26.389 --> 00:21:28.549
- so so the LHC at the moment, I'm
594
00:21:28.549 --> 00:21:30.710
- I'm not sure if it's is it shut
595
00:21:30.710 --> 00:21:33.049
- down for the high luminosity
596
00:21:33.509 --> 00:21:35.529
- upgrade or is it Yeah. It's about to.
597
00:21:35.589 --> 00:21:38.815
- About to. Right. So, you know, that's going
598
00:21:38.815 --> 00:21:41.294
- to take a few years. And, I mean,
599
00:21:41.294 --> 00:21:43.934
- I would imagine that when the LHC is
600
00:21:43.934 --> 00:21:45.554
- back and up and running,
601
00:21:46.894 --> 00:21:48.174
- I mean, is it going to be a
602
00:21:48.174 --> 00:21:51.214
- different world for particle physicists? Because all these
603
00:21:51.214 --> 00:21:53.400
- machine learning and AI techniques
604
00:21:53.940 --> 00:21:54.839
- will have been
605
00:21:55.220 --> 00:21:55.720
- developed
606
00:21:56.179 --> 00:21:56.679
- and,
607
00:21:57.140 --> 00:21:57.640
- matured.
608
00:21:58.339 --> 00:22:01.079
- And also, you know, we we've got another
609
00:22:01.140 --> 00:22:02.839
- few years of quantum computing
610
00:22:03.380 --> 00:22:05.380
- progress to be made. I mean, you I
611
00:22:05.380 --> 00:22:07.214
- I mean, it sounds to me like you,
612
00:22:07.694 --> 00:22:10.115
- and your colleagues should be very excited
613
00:22:11.054 --> 00:22:11.554
- about,
614
00:22:12.095 --> 00:22:14.894
- a new sort of paradigm in how you
615
00:22:14.894 --> 00:22:15.375
- can,
616
00:22:15.855 --> 00:22:18.894
- interpret data from the LHC, and lots more
617
00:22:18.894 --> 00:22:19.394
- data,
618
00:22:20.490 --> 00:22:22.250
- that that is a result of the of
619
00:22:22.250 --> 00:22:24.250
- the upgrade. I mean, it it must be
620
00:22:24.250 --> 00:22:25.070
- very exciting.
621
00:22:25.609 --> 00:22:27.769
- Yeah. Well, exactly. And that point, if I
622
00:22:27.769 --> 00:22:28.970
- made it there at the end, is is
623
00:22:28.970 --> 00:22:30.330
- the crucial one. I mean, it's coming at
624
00:22:30.330 --> 00:22:32.170
- the right time. There's this high luminosity upgrade
625
00:22:32.170 --> 00:22:34.164
- is gonna give even more data. So that
626
00:22:34.164 --> 00:22:36.085
- would almost be quite scary if we weren't
627
00:22:36.085 --> 00:22:38.404
- equipped with the right tools to combat that,
628
00:22:38.404 --> 00:22:40.404
- and that's exactly what AI and machine learning
629
00:22:40.404 --> 00:22:42.404
- give us access to. And also, it's worth
630
00:22:42.404 --> 00:22:43.525
- saying that, I mean, a lot of my
631
00:22:43.525 --> 00:22:46.210
- work, I don't work directly with datasets of
632
00:22:46.210 --> 00:22:47.970
- a large Hadron Collider often, and the kind
633
00:22:47.970 --> 00:22:49.190
- of stuff that interests me
634
00:22:49.650 --> 00:22:53.430
- in parallel is this simulation using quantum computers
635
00:22:53.730 --> 00:22:54.309
- to simulate
636
00:22:54.690 --> 00:22:55.670
- particle interactions.
637
00:22:56.210 --> 00:22:57.730
- So we can build that on a a
638
00:22:57.730 --> 00:22:58.789
- tabletop experiment.
639
00:22:59.794 --> 00:23:02.434
- Obviously, we need probably thousands and thousands at
640
00:23:02.434 --> 00:23:03.815
- least of qubits.
641
00:23:04.275 --> 00:23:05.634
- So that might be a little while away,
642
00:23:05.634 --> 00:23:07.474
- but I can think of the algorithms now
643
00:23:07.474 --> 00:23:09.075
- and say one day when you give me
644
00:23:09.075 --> 00:23:11.154
- a tabletop of qubits, this is what I'm
645
00:23:11.154 --> 00:23:12.775
- gonna run and I'm gonna simulate
646
00:23:13.079 --> 00:23:15.079
- a particle interaction. And so we can kind
647
00:23:15.079 --> 00:23:17.339
- of attack it from two angles, top down
648
00:23:17.400 --> 00:23:19.400
- at the LHC. Look at all this data.
649
00:23:19.400 --> 00:23:21.880
- Let's go deep diving into it. And bottom
650
00:23:21.880 --> 00:23:24.539
- up from tabletop quantum computing experiments.
651
00:23:24.839 --> 00:23:27.400
- Let's try and build a simulation of these
652
00:23:27.400 --> 00:23:28.804
- and see if we can expect it from
653
00:23:28.804 --> 00:23:31.065
- below. So we can kind of pincer movement,
654
00:23:31.444 --> 00:23:33.605
- the the standard model of the universe, and
655
00:23:33.605 --> 00:23:35.384
- try and understand more about it.
656
00:23:36.724 --> 00:23:39.125
- And, Ross, I wanted to to shift gears
657
00:23:39.125 --> 00:23:41.224
- a bit and and talk about
658
00:23:41.529 --> 00:23:44.829
- how quantum computers could be used to
659
00:23:45.609 --> 00:23:48.190
- to, I suppose, solve one of the the
660
00:23:48.410 --> 00:23:49.470
- the biggest challenges
661
00:23:49.769 --> 00:23:52.750
- facing physicists at the moment, and that is
662
00:23:52.890 --> 00:23:53.390
- developing
663
00:23:53.769 --> 00:23:54.589
- a viable
664
00:23:55.454 --> 00:23:55.954
- quantum
665
00:23:56.255 --> 00:23:58.815
- theory of gravity. You know, at the moment,
666
00:23:58.815 --> 00:24:00.194
- quantum mechanics is
667
00:24:00.494 --> 00:24:01.234
- an extraordinarily
668
00:24:02.494 --> 00:24:03.714
- successful theory.
669
00:24:04.174 --> 00:24:05.394
- And, Einstein's
670
00:24:05.934 --> 00:24:08.755
- general theory of relativity does a great job
671
00:24:09.259 --> 00:24:10.559
- at describing gravity.
672
00:24:10.940 --> 00:24:14.159
- But, it has proven very difficult to bring
673
00:24:14.619 --> 00:24:17.259
- those two things together in a in a
674
00:24:17.259 --> 00:24:20.960
- theory that works. So how could quantum computers
675
00:24:21.099 --> 00:24:21.599
- help,
676
00:24:22.139 --> 00:24:23.119
- with that challenge?
677
00:24:24.015 --> 00:24:25.775
- Yeah. I mean, exactly like you say that
678
00:24:25.775 --> 00:24:28.815
- they're kind of fundamentally incompatible despite being two
679
00:24:28.815 --> 00:24:31.295
- of the most well verified theories in all
680
00:24:31.295 --> 00:24:34.174
- science. It is quite counterintuitive, but general relativity
681
00:24:34.174 --> 00:24:36.734
- speaks in this language of continuous space and
682
00:24:36.734 --> 00:24:38.355
- time and deterministic
683
00:24:38.734 --> 00:24:39.234
- results.
684
00:24:39.750 --> 00:24:42.070
- And quantum mechanics speaks in this language of
685
00:24:42.070 --> 00:24:43.769
- discretized space, quantized
686
00:24:44.070 --> 00:24:46.890
- space, and energy levels, and and not deterministic
687
00:24:46.950 --> 00:24:49.349
- at all. It's it's inherently probabilistic, and so
688
00:24:49.349 --> 00:24:52.150
- they're completely different languages. The mathematical toolbox that
689
00:24:52.150 --> 00:24:54.009
- you use for them both are completely different.
690
00:24:54.285 --> 00:24:55.965
- So for that reason, they're incompatible, but they're
691
00:24:55.965 --> 00:24:57.884
- also if you try and quantize gravity or
692
00:24:57.884 --> 00:24:59.965
- gravitize quantum, you end up with a bunch
693
00:24:59.965 --> 00:25:00.625
- of divergences,
694
00:25:00.924 --> 00:25:02.144
- so infinite terms.
695
00:25:02.525 --> 00:25:03.025
- So
696
00:25:03.325 --> 00:25:06.285
- for example, if you try to quantize gravity
697
00:25:06.285 --> 00:25:07.884
- and think of a particle, call it the
698
00:25:07.884 --> 00:25:08.384
- graviton,
699
00:25:08.799 --> 00:25:10.259
- it's infamously unrenormalizable.
700
00:25:10.960 --> 00:25:12.240
- I know there are some people who might
701
00:25:12.240 --> 00:25:13.440
- take issue with that, but that's kind of
702
00:25:13.440 --> 00:25:16.500
- general consensus. Right? So it's it's really difficult.
703
00:25:16.799 --> 00:25:18.640
- So this is where I'm gonna come back
704
00:25:18.640 --> 00:25:20.500
- to trying to do the bottom up approach
705
00:25:20.960 --> 00:25:21.460
- because
706
00:25:22.125 --> 00:25:23.265
- there are some theories
707
00:25:23.644 --> 00:25:26.525
- that are dual theories of quantum and gravity.
708
00:25:26.525 --> 00:25:28.684
- Now they're not theories of our universe. They're
709
00:25:28.684 --> 00:25:30.464
- theories of kind of toy models,
710
00:25:31.005 --> 00:25:32.065
- but it's this idea
711
00:25:32.445 --> 00:25:33.265
- called the holographic
712
00:25:33.565 --> 00:25:34.065
- principle.
713
00:25:34.605 --> 00:25:36.285
- And the idea is if you come up
714
00:25:36.285 --> 00:25:36.900
- with some
715
00:25:37.460 --> 00:25:39.700
- quantum theory and you calculate a bunch of
716
00:25:39.700 --> 00:25:41.880
- quantities in this quantum theory,
717
00:25:42.980 --> 00:25:44.200
- it's actually equivalent
718
00:25:44.820 --> 00:25:48.279
- to a gravitational theory that's not quantum whatsoever
719
00:25:48.900 --> 00:25:50.599
- in one dimension higher,
720
00:25:50.974 --> 00:25:52.755
- so an extra space time dimension,
721
00:25:53.695 --> 00:25:55.535
- and you calculate the same quantities, you get
722
00:25:55.535 --> 00:25:56.515
- the same results.
723
00:25:57.134 --> 00:25:59.855
- So, again, one is not contingent on the
724
00:25:59.855 --> 00:26:02.575
- other, but two different theories give the same
725
00:26:02.575 --> 00:26:04.195
- results, almost to imply
726
00:26:04.700 --> 00:26:06.640
- that if you have a gravitational theory,
727
00:26:07.180 --> 00:26:10.299
- the more fundamental version is this quantum mechanical
728
00:26:10.299 --> 00:26:12.240
- theory that exists in fewer dimensions.
729
00:26:12.619 --> 00:26:14.460
- So, for example, something you could do on
730
00:26:14.460 --> 00:26:16.875
- a tabletop is something called the SYK model,
731
00:26:17.035 --> 00:26:18.894
- the SAC devier Kitaev model.
732
00:26:19.275 --> 00:26:21.775
- And that's actually a zero plus one dimensional
733
00:26:21.835 --> 00:26:24.335
- theory, which means a zero space dimensions
734
00:26:24.875 --> 00:26:27.035
- and one time dimension. So it starts to
735
00:26:27.035 --> 00:26:29.289
- get very wacky, very hard to picture. It
736
00:26:29.289 --> 00:26:31.130
- says, imagine you have a bunch of particles,
737
00:26:31.130 --> 00:26:33.150
- essentially. They're called Majorana fermions.
738
00:26:33.849 --> 00:26:35.230
- You have a bunch of these particles.
739
00:26:35.769 --> 00:26:37.849
- They don't exist in space because space doesn't
740
00:26:37.849 --> 00:26:39.769
- exist, but we can still label them in
741
00:26:39.769 --> 00:26:40.829
- the kind of abstract,
742
00:26:41.625 --> 00:26:42.445
- and they do
743
00:26:42.984 --> 00:26:45.545
- change with time and their correlation has changed
744
00:26:45.545 --> 00:26:46.664
- with time. And all you do is you
745
00:26:46.664 --> 00:26:48.845
- randomly couple different groups of these particles.
746
00:26:49.144 --> 00:26:50.984
- And then there's your quantum theory and you
747
00:26:50.984 --> 00:26:52.664
- calculate a few things and it's quite a
748
00:26:52.664 --> 00:26:53.404
- simple theory,
749
00:26:53.865 --> 00:26:56.345
- something that we could try and build using
750
00:26:56.345 --> 00:26:57.669
- qubits in a lab.
751
00:26:58.690 --> 00:27:01.089
- What actually happens is really interesting is that
752
00:27:01.089 --> 00:27:03.029
- the results you get are equivalent
753
00:27:03.410 --> 00:27:06.130
- to something called j t gravity. So this
754
00:27:06.130 --> 00:27:07.910
- is this is a one plus one dimensional
755
00:27:08.450 --> 00:27:11.305
- theory. So one dimension of space, so it
756
00:27:11.305 --> 00:27:12.924
- exists on a line basically
757
00:27:13.305 --> 00:27:14.605
- and varies in time.
758
00:27:15.144 --> 00:27:16.205
- So you have this
759
00:27:16.585 --> 00:27:19.164
- baseline quantum model, this SYK model,
760
00:27:19.945 --> 00:27:22.744
- almost giving rise to gravity and giving rise
761
00:27:22.744 --> 00:27:24.424
- to a dimension of space because the two
762
00:27:24.424 --> 00:27:25.724
- theories give the same results.
763
00:27:26.570 --> 00:27:28.410
- So this is really interesting. Obviously, we don't
764
00:27:28.410 --> 00:27:30.089
- live on a line. We don't live in
765
00:27:30.089 --> 00:27:32.170
- a one plus one dimensional universe, so it's
766
00:27:32.170 --> 00:27:34.329
- not useful for us in our understanding of
767
00:27:34.329 --> 00:27:36.490
- our universe. But if we can build a
768
00:27:36.490 --> 00:27:37.470
- tabletop experiment
769
00:27:38.009 --> 00:27:39.769
- that doesn't have gravity in it at all,
770
00:27:39.769 --> 00:27:41.595
- just has entanglement and cubits,
771
00:27:41.994 --> 00:27:45.454
- and from that get results that mimic gravity,
772
00:27:46.154 --> 00:27:48.315
- then perhaps we can make the argument that
773
00:27:48.315 --> 00:27:50.734
- gravity and actually space itself
774
00:27:51.115 --> 00:27:52.654
- and perhaps even time
775
00:27:53.115 --> 00:27:56.015
- are emergent properties of quantum entanglement.
776
00:27:56.460 --> 00:27:58.539
- So this is the idea of emergent space
777
00:27:58.539 --> 00:28:00.400
- time, and this is the kind of way
778
00:28:00.460 --> 00:28:02.880
- that we could attack quantum gravity. Rather than
779
00:28:02.940 --> 00:28:05.919
- gravitize quantum or quantize gravity, let's
780
00:28:06.220 --> 00:28:09.500
- use fundamental quantum building blocks to build space
781
00:28:09.500 --> 00:28:10.480
- and time itself.
782
00:28:12.315 --> 00:28:15.274
- And that that takes me nicely to to
783
00:28:15.274 --> 00:28:18.315
- my final question for you, Ross. And I
784
00:28:18.315 --> 00:28:19.294
- I suppose it's
785
00:28:20.474 --> 00:28:23.534
- a more general question about the intersection between
786
00:28:23.835 --> 00:28:24.654
- quantum mechanics
787
00:28:25.115 --> 00:28:26.894
- and, general relativity.
788
00:28:28.519 --> 00:28:31.079
- Quantum information theory, which is the sort of
789
00:28:31.079 --> 00:28:32.619
- the conceptual framework
790
00:28:33.160 --> 00:28:33.660
- behind
791
00:28:34.200 --> 00:28:36.220
- quantum computers, is being used
792
00:28:36.519 --> 00:28:37.259
- to study
793
00:28:37.640 --> 00:28:38.940
- that interface.
794
00:28:40.454 --> 00:28:40.954
- And
795
00:28:41.255 --> 00:28:42.775
- it it it seems to be throwing up
796
00:28:42.775 --> 00:28:44.394
- some really interesting things.
797
00:28:45.015 --> 00:28:47.494
- I mean, I I wrote an article probably
798
00:28:47.494 --> 00:28:50.555
- about a year ago about something called,
799
00:28:51.575 --> 00:28:52.075
- indefinite
800
00:28:52.639 --> 00:28:55.519
- causal order, which is a really strange thing
801
00:28:55.519 --> 00:28:57.119
- when you when you start,
802
00:28:57.599 --> 00:28:58.099
- combining,
803
00:28:58.880 --> 00:28:59.779
- quantum mechanics
804
00:29:00.079 --> 00:29:01.460
- and general relativity.
805
00:29:03.359 --> 00:29:03.859
- And,
806
00:29:04.795 --> 00:29:06.714
- quantum information theory is, you know, it's been
807
00:29:06.714 --> 00:29:08.575
- shedding light on the nature of
808
00:29:08.875 --> 00:29:09.775
- space time,
809
00:29:10.154 --> 00:29:12.474
- black holes, and, you know, all those sort
810
00:29:12.474 --> 00:29:14.875
- of wonderful things. Can you talk a bit
811
00:29:14.875 --> 00:29:15.375
- about
812
00:29:15.914 --> 00:29:18.875
- what sort of insights quantum information theory can
813
00:29:18.875 --> 00:29:21.429
- give us into the, you know, the universe
814
00:29:21.429 --> 00:29:23.210
- in general, I suppose, beyond
815
00:29:23.509 --> 00:29:26.069
- the quantum world. Yeah. And it's really, really
816
00:29:26.069 --> 00:29:28.549
- interesting. So information is kind of this abstract
817
00:29:28.549 --> 00:29:29.929
- concept, but it's
818
00:29:30.309 --> 00:29:33.190
- often proposed as being fundamental in the universe
819
00:29:33.190 --> 00:29:35.210
- and and information is always conserved.
820
00:29:35.664 --> 00:29:37.265
- And so when you have information about, for
821
00:29:37.265 --> 00:29:38.244
- example, a thermodynamic
822
00:29:39.265 --> 00:29:42.305
- room of particles, you you apply something called
823
00:29:42.305 --> 00:29:44.464
- statistical mechanics to that, and you can get
824
00:29:44.464 --> 00:29:46.384
- some conclusions about the information in the room,
825
00:29:46.384 --> 00:29:48.545
- often this thing called entropy. Right? So may
826
00:29:48.545 --> 00:29:51.289
- have heard of entropy before. There's quantum mechanical
827
00:29:51.289 --> 00:29:53.450
- equivalent. Imagine you have lots of quantum particles
828
00:29:53.450 --> 00:29:54.890
- and you can do this the field of
829
00:29:54.890 --> 00:29:55.869
- quantum information.
830
00:29:56.490 --> 00:29:59.210
- And within that, there are definitions of entropy
831
00:29:59.210 --> 00:30:00.890
- about how much we know about this quantum
832
00:30:00.890 --> 00:30:02.595
- system, how much we don't know, what if
833
00:30:02.595 --> 00:30:03.954
- we only look at part of it, what
834
00:30:03.954 --> 00:30:06.515
- does that teach us about potentially entanglement between
835
00:30:06.515 --> 00:30:08.835
- different regions, things like that. And this toolbox
836
00:30:08.835 --> 00:30:10.355
- has been developed for a little while and
837
00:30:10.355 --> 00:30:12.515
- it's really interesting, and it kind of can
838
00:30:12.515 --> 00:30:13.634
- give us a bunch of stuff to do
839
00:30:13.634 --> 00:30:14.730
- with quantum computers.
840
00:30:15.210 --> 00:30:16.730
- But then in parallel, the field of black
841
00:30:16.730 --> 00:30:19.450
- holes was developing their own little toolbox to
842
00:30:19.450 --> 00:30:22.089
- try and understand the event horizon and what
843
00:30:22.089 --> 00:30:24.009
- happens to things that falls inside a black
844
00:30:24.009 --> 00:30:26.029
- hole. And then really surprisingly,
845
00:30:26.970 --> 00:30:27.795
- some of the results
846
00:30:28.275 --> 00:30:29.875
- again seem to match. It seemed to be
847
00:30:29.875 --> 00:30:31.475
- that, actually, we can start using these ideas
848
00:30:31.475 --> 00:30:34.674
- of quantum information theory on black holes themselves.
849
00:30:34.674 --> 00:30:35.414
- And, actually,
850
00:30:36.035 --> 00:30:38.515
- our current understanding, and this is really bleeding
851
00:30:38.515 --> 00:30:40.355
- edge physics at the moment, so this might
852
00:30:40.355 --> 00:30:42.059
- change, but But our current understanding is if
853
00:30:42.059 --> 00:30:44.079
- something falls into a black hole, that information
854
00:30:44.140 --> 00:30:45.200
- isn't lost forever.
855
00:30:45.819 --> 00:30:48.299
- It's actually encoded in some sense on the
856
00:30:48.299 --> 00:30:49.759
- surface of the black hole
857
00:30:50.220 --> 00:30:52.859
- on the event horizon. And Leonard Susskind would
858
00:30:52.859 --> 00:30:55.039
- be an advocate for saying it goes inside
859
00:30:55.394 --> 00:30:57.154
- and outside the black hole. This is the
860
00:30:57.154 --> 00:30:58.695
- idea of black hole complementarity.
861
00:30:59.154 --> 00:31:00.914
- So there's some really interesting stuff here, but
862
00:31:00.914 --> 00:31:03.955
- the idea is it's preserved. It's encoded, almost
863
00:31:03.955 --> 00:31:06.055
- encrypted, and it's done so redundantly.
864
00:31:06.434 --> 00:31:08.355
- So you don't need the entire surface of
865
00:31:08.355 --> 00:31:10.769
- the black hole to reconstruct all of the
866
00:31:10.769 --> 00:31:13.329
- information, almost as if it's error correcting in
867
00:31:13.329 --> 00:31:16.069
- some way. And then that information is slowly
868
00:31:16.130 --> 00:31:18.609
- released back into the universe over billions of
869
00:31:18.609 --> 00:31:19.669
- billions of years
870
00:31:19.970 --> 00:31:22.450
- through Hawking radiation. So some really interesting stuff,
871
00:31:22.450 --> 00:31:24.684
- and all of this has been found out
872
00:31:24.684 --> 00:31:27.024
- by applying this toolbox of quantum information
873
00:31:27.565 --> 00:31:30.865
- to black hole physics and to these extreme
874
00:31:30.924 --> 00:31:34.605
- environments where there's interesting quantum mechanical effects and
875
00:31:34.605 --> 00:31:36.960
- strong gravitational effects. So this could be a
876
00:31:36.960 --> 00:31:39.859
- good playground to understand quantum gravity, for example.
877
00:31:40.160 --> 00:31:41.920
- So this is a kind of idea that
878
00:31:41.920 --> 00:31:45.460
- we can apply quantum information to perhaps surprising
879
00:31:45.599 --> 00:31:48.224
- areas of physics and learn quite a lot.
880
00:31:50.304 --> 00:31:52.464
- Yeah. That that that is really interesting. I
881
00:31:52.464 --> 00:31:53.765
- mean, is this this,
882
00:31:56.065 --> 00:31:57.924
- black hole? Is it that firewall?
883
00:31:58.304 --> 00:32:00.065
- I I I remember there's a lot of
884
00:32:00.065 --> 00:32:00.930
- work about that.
885
00:32:01.410 --> 00:32:03.570
- Maybe five years ago, there was a flurry
886
00:32:03.570 --> 00:32:03.890
- of,
887
00:32:04.610 --> 00:32:06.950
- of papers. And, yeah, I remember
888
00:32:07.410 --> 00:32:08.390
- really struggling
889
00:32:08.930 --> 00:32:10.309
- to get my head around,
890
00:32:10.930 --> 00:32:13.009
- exactly what was going on. But, yeah, I
891
00:32:13.009 --> 00:32:15.375
- mean, that is a really interesting it's is
892
00:32:15.375 --> 00:32:18.115
- that is that the black hole information paradox?
893
00:32:18.255 --> 00:32:20.575
- Exactly. So the information paradox originally was when
894
00:32:20.575 --> 00:32:21.715
- when Stephen Hawking
895
00:32:22.174 --> 00:32:23.775
- came up with, oh, hold on. That there's
896
00:32:23.775 --> 00:32:25.934
- some kind of radiation that's leading out. But
897
00:32:25.934 --> 00:32:27.980
- he said that radiation cannot
898
00:32:28.440 --> 00:32:30.759
- contain the information. The information's inside the black
899
00:32:30.759 --> 00:32:31.580
- hole. Right?
900
00:32:31.960 --> 00:32:33.799
- So but the problem is if if a
901
00:32:33.799 --> 00:32:36.700
- black hole is radiating, it's it's slowly shrinking.
902
00:32:37.000 --> 00:32:38.984
- So eventually, that black hole will disappear. So
903
00:32:39.144 --> 00:32:40.684
- if the information is not in the radiation
904
00:32:40.825 --> 00:32:42.984
- and it's the black hole is gone, where's
905
00:32:42.984 --> 00:32:43.565
- the information?
906
00:32:43.865 --> 00:32:46.025
- So this was the information paradox. And he
907
00:32:46.025 --> 00:32:48.684
- actually had a bet, with with, with Preskill
908
00:32:48.825 --> 00:32:49.464
- about this.
909
00:32:50.025 --> 00:32:52.549
- And he said, Preskill said that, no. The
910
00:32:52.549 --> 00:32:54.789
- information must be in in in your radiation,
911
00:32:54.789 --> 00:32:57.349
- in the Hawking radiation. And Stephen Hawking disagreed,
912
00:32:57.349 --> 00:32:59.830
- but eventually conceded that that he was correct.
913
00:32:59.830 --> 00:33:01.430
- And that that is where we're at at
914
00:33:01.430 --> 00:33:04.390
- the moment. We think the information is indeed
915
00:33:04.390 --> 00:33:07.034
- in the Hawking radiation. So it is really
916
00:33:07.034 --> 00:33:09.514
- interesting. Really interesting. And, again, this could change,
917
00:33:09.835 --> 00:33:11.355
- but this is what's so exciting about the
918
00:33:11.355 --> 00:33:11.855
- field.
919
00:33:12.234 --> 00:33:14.714
- Yeah. Yeah. Yeah. It it it's all coming
920
00:33:14.714 --> 00:33:16.474
- back to me now. And then you've got
921
00:33:16.474 --> 00:33:19.294
- this no is it the no hair theorem?
922
00:33:19.779 --> 00:33:21.539
- Yeah. Is that is that at the heart
923
00:33:21.539 --> 00:33:23.400
- of the paradox that the black hole
924
00:33:23.940 --> 00:33:24.440
- can't
925
00:33:25.140 --> 00:33:27.859
- hold this information or that it shouldn't be
926
00:33:27.859 --> 00:33:29.779
- there or Yeah. There can't be kind of,
927
00:33:29.940 --> 00:33:31.700
- this kind of fuzzy thing that happens on
928
00:33:31.700 --> 00:33:33.315
- the edge. But this is all all kind
929
00:33:33.315 --> 00:33:35.315
- of intertwined, and and the firewall that you
930
00:33:35.315 --> 00:33:37.315
- mentioned earlier is kind of, again, up for
931
00:33:37.315 --> 00:33:39.654
- debate. So some people would would believe that
932
00:33:39.714 --> 00:33:41.954
- you can't cross the event horizon because you
933
00:33:41.954 --> 00:33:43.474
- would you would tear up. It would kind
934
00:33:43.474 --> 00:33:46.259
- of become infinite temperature. That isn't really the
935
00:33:46.259 --> 00:33:48.019
- prevailing theory at the moment. I think it's
936
00:33:48.019 --> 00:33:50.340
- slightly more common to say that if you
937
00:33:50.340 --> 00:33:52.420
- invoke the equivalence principle, which means that if
938
00:33:52.420 --> 00:33:53.860
- you're in free fall, you're not supposed to
939
00:33:53.860 --> 00:33:55.299
- be able to tell if that you're in
940
00:33:55.299 --> 00:33:57.620
- a particularly special environment, including that of the
941
00:33:57.620 --> 00:33:59.934
- event horizon. So for us if it was
942
00:33:59.934 --> 00:34:02.095
- a small black hole, the tidal effects would
943
00:34:02.095 --> 00:34:03.934
- rip you apart, so you could definitely tell.
944
00:34:03.934 --> 00:34:05.534
- But if it was a really supermassive black
945
00:34:05.534 --> 00:34:07.454
- hole, you could pass the event horizon and
946
00:34:07.454 --> 00:34:09.054
- not even notice. We could be doing it
947
00:34:09.054 --> 00:34:10.574
- right now. The Earth could be falling into
948
00:34:10.574 --> 00:34:13.074
- some supermassive black hole, and we wouldn't know.
949
00:34:13.135 --> 00:34:13.739
- So this is
950
00:34:14.300 --> 00:34:15.920
- kind of what we think
951
00:34:16.300 --> 00:34:18.320
- is happening. Obviously, if you look at someone
952
00:34:18.460 --> 00:34:19.280
- from afar
953
00:34:19.579 --> 00:34:22.079
- because of general relativity and different different
954
00:34:22.699 --> 00:34:25.579
- perspectives, different frames, you would see something different.
955
00:34:25.579 --> 00:34:27.420
- You would never see them pass the event
956
00:34:27.420 --> 00:34:30.224
- horizons black of the black hole because time
957
00:34:30.224 --> 00:34:32.244
- dilates infinitely. So that light
958
00:34:32.545 --> 00:34:34.464
- is never gonna reach you of them of
959
00:34:34.464 --> 00:34:36.464
- them passing the black hole. So this is
960
00:34:36.464 --> 00:34:38.964
- kind of, again, leading back into the Susskind
961
00:34:39.025 --> 00:34:39.844
- view of complementarity.
962
00:34:40.224 --> 00:34:42.559
- You you you almost pass the event horizon
963
00:34:42.559 --> 00:34:44.559
- and don't pass the event horizon, and something
964
00:34:44.559 --> 00:34:46.260
- is also true for information.
965
00:34:46.559 --> 00:34:48.179
- So really, really cool stuff.
966
00:34:48.719 --> 00:34:50.739
- Yeah. It is I mean, it is astonishing,
967
00:34:50.800 --> 00:34:52.640
- or at least I find it astonishing that
968
00:34:52.640 --> 00:34:54.974
- you can you can have these sort of
969
00:34:54.974 --> 00:34:56.194
- quantum conversations
970
00:34:56.574 --> 00:34:58.655
- about a black hole, which is, you know,
971
00:34:58.655 --> 00:35:01.074
- something that's huge and, you know,
972
00:35:01.494 --> 00:35:01.994
- the
973
00:35:02.414 --> 00:35:03.714
- incredibly violent
974
00:35:04.335 --> 00:35:04.835
- gravitational
975
00:35:05.534 --> 00:35:07.295
- field that it has. You would have thought
976
00:35:07.295 --> 00:35:09.150
- it would it would be the least quantum
977
00:35:09.150 --> 00:35:10.130
- thing in the world.
978
00:35:10.429 --> 00:35:12.750
- Yet, you know, you've got all these subtle
979
00:35:12.750 --> 00:35:13.250
- effects,
980
00:35:14.109 --> 00:35:16.670
- that you that I suppose quantum mechanics forces
981
00:35:16.670 --> 00:35:18.849
- you Yeah. To to think about.
982
00:35:19.309 --> 00:35:20.449
- Well, that's what I mean.
983
00:35:20.829 --> 00:35:22.190
- Everywhere. Even in the the vacuum of empty
984
00:35:22.190 --> 00:35:22.394
- spaces,
985
00:35:28.875 --> 00:35:32.255
- motivation to explain Hawking radiation. Even the vacuum,
986
00:35:32.554 --> 00:35:33.994
- right at the boundary of a black hole
987
00:35:33.994 --> 00:35:36.179
- at the event horizon, There's interesting stuff happening
988
00:35:36.179 --> 00:35:38.179
- there. There's an interaction between these really cool
989
00:35:38.179 --> 00:35:38.679
- environments.
990
00:35:40.900 --> 00:35:43.139
- Well, that's great, Ross. Thanks so much for
991
00:35:43.139 --> 00:35:45.539
- for coming on the podcast and and talking
992
00:35:45.539 --> 00:35:48.440
- to us about quantum computing and particle physics,
993
00:35:49.265 --> 00:35:52.485
- quantum gravity, and black holes as well.
994
00:35:53.184 --> 00:35:54.465
- So so what's some
995
00:35:55.585 --> 00:35:57.684
- you mentioned some of your research,
996
00:35:57.985 --> 00:36:00.565
- at the moment. Is there anything in particular
997
00:36:00.625 --> 00:36:02.545
- that you're working on now that you'd like
998
00:36:02.545 --> 00:36:04.429
- to share with our audience?
999
00:36:05.289 --> 00:36:06.730
- Yeah. So, I mean, so I I finished
1000
00:36:06.730 --> 00:36:09.309
- my PhD last year, actually, and it was
1001
00:36:09.369 --> 00:36:12.010
- mostly related in kind of causality for quantum
1002
00:36:12.010 --> 00:36:14.730
- field theory. So the mathematical framework of of
1003
00:36:14.730 --> 00:36:16.944
- our best theory of quantum mechanics. And now
1004
00:36:16.944 --> 00:36:18.085
- I'm pivoting into
1005
00:36:18.385 --> 00:36:20.864
- actually kind of more applications for quantum computers.
1006
00:36:20.864 --> 00:36:22.784
- So hopefully later this year, I'll have some
1007
00:36:22.784 --> 00:36:25.025
- papers out that are gonna be about the
1008
00:36:25.025 --> 00:36:26.944
- kind of algorithms that we can use to
1009
00:36:26.944 --> 00:36:27.444
- simulate
1010
00:36:27.984 --> 00:36:29.284
- quantum field theories
1011
00:36:29.585 --> 00:36:32.324
- on qubits. So hopefully, stay tuned for that.
1012
00:36:33.059 --> 00:36:34.340
- And I think, I mean, I think we've
1013
00:36:34.340 --> 00:36:36.660
- got a good careers message here. I mean,
1014
00:36:36.660 --> 00:36:38.760
- we we love to talk about careers
1015
00:36:39.140 --> 00:36:40.680
- on the Physics World podcast.
1016
00:36:41.219 --> 00:36:41.719
- And,
1017
00:36:42.099 --> 00:36:43.860
- you know, it sounds to me that,
1018
00:36:44.980 --> 00:36:47.079
- you you can do particle physics.
1019
00:36:47.565 --> 00:36:50.125
- And then, I mean, maybe you're not going
1020
00:36:50.125 --> 00:36:52.125
- to do this or maybe you will, that
1021
00:36:52.125 --> 00:36:53.905
- you can move into a career
1022
00:36:54.605 --> 00:36:56.144
- in quantum computing
1023
00:36:56.605 --> 00:36:58.925
- fairly seamlessly. I mean, is that right? Would
1024
00:36:58.925 --> 00:37:00.570
- you I mean, if somebody came to you
1025
00:37:00.570 --> 00:37:02.170
- and said, well, you know, I'm really interested
1026
00:37:02.170 --> 00:37:03.309
- in particle physics,
1027
00:37:03.610 --> 00:37:05.450
- but I wanna get a job at a
1028
00:37:05.450 --> 00:37:08.170
- quantum computing company. I mean, it sounds to
1029
00:37:08.170 --> 00:37:08.809
- me like,
1030
00:37:09.369 --> 00:37:11.784
- doing a PhD in particle physics be a
1031
00:37:11.784 --> 00:37:12.445
- good idea.
1032
00:37:12.824 --> 00:37:15.224
- Yeah. Yeah. I mean, the the boundaries are
1033
00:37:15.224 --> 00:37:16.905
- definitely getting more and more blurred as time
1034
00:37:16.905 --> 00:37:19.085
- goes on, as we've discussed the ideas of
1035
00:37:19.385 --> 00:37:21.945
- AI, machine learning, even qubits starting to be
1036
00:37:21.945 --> 00:37:24.760
- applied in particle physics. And so it becomes
1037
00:37:24.760 --> 00:37:25.500
- very interdisciplinary.
1038
00:37:25.880 --> 00:37:27.719
- And, actually, my my masters that I did
1039
00:37:27.719 --> 00:37:28.699
- before my PhD
1040
00:37:29.159 --> 00:37:31.319
- was half in quantum computing and half in
1041
00:37:31.319 --> 00:37:33.819
- particle physics. And so I always kind of
1042
00:37:34.119 --> 00:37:35.960
- balanced it because I'm interested in both. And
1043
00:37:35.960 --> 00:37:37.605
- so I've I've managed to be be very
1044
00:37:37.605 --> 00:37:39.445
- lucky in that I get to study both
1045
00:37:39.445 --> 00:37:41.625
- fields simultaneously. But, yeah, you can absolutely
1046
00:37:41.925 --> 00:37:42.985
- absolutely pivot.
1047
00:37:44.244 --> 00:37:45.925
- Well, that's great, Ross. Well, thanks again for
1048
00:37:45.925 --> 00:37:48.085
- coming on the podcast. Thank you very much
1049
00:37:48.085 --> 00:37:48.985
- for having me.
1050
00:37:56.519 --> 00:37:59.400
- That was Ross Jenkinson of the University of
1051
00:37:59.400 --> 00:37:59.900
- Manchester.
1052
00:38:00.440 --> 00:38:02.940
- Thanks, Ross, for a fascinating discussion.
1053
00:38:03.744 --> 00:38:06.144
- This podcast is brought to you by American
1054
00:38:06.144 --> 00:38:06.644
- Elements,
1055
00:38:07.105 --> 00:38:08.164
- the world's leading
1056
00:38:08.545 --> 00:38:09.045
- manufacturer
1057
00:38:09.425 --> 00:38:11.764
- of engineered and advanced materials.
1058
00:38:12.385 --> 00:38:15.204
- With a catalog of over 35,000
1059
00:38:15.344 --> 00:38:19.349
- products available in both industrial bulk and laboratory
1060
00:38:19.650 --> 00:38:20.150
- quantities,
1061
00:38:20.769 --> 00:38:23.809
- American Elements is the largest supplier of its
1062
00:38:23.809 --> 00:38:24.309
- kind.
1063
00:38:24.849 --> 00:38:27.410
- For more than twenty five years, its research
1064
00:38:27.410 --> 00:38:30.715
- and development programs have been a vital resource
1065
00:38:30.715 --> 00:38:31.534
- for innovation
1066
00:38:31.994 --> 00:38:35.295
- across corporate, government, and academic sectors.
1067
00:38:35.914 --> 00:38:38.574
- The company's ability to scale laboratory
1068
00:38:38.875 --> 00:38:40.974
- breakthroughs to industrial production
1069
00:38:41.355 --> 00:38:43.855
- has contributed to many of the most significant
1070
00:38:44.480 --> 00:38:44.980
- technological
1071
00:38:45.280 --> 00:38:47.460
- advances since 1990,
1072
00:38:48.079 --> 00:38:49.699
- including LED lighting,
1073
00:38:50.079 --> 00:38:50.579
- smartphones,
1074
00:38:50.960 --> 00:38:52.260
- and electric vehicles.
1075
00:38:52.880 --> 00:38:56.980
- To learn more, visit americanelements.com.
1076
00:38:57.440 --> 00:38:57.940
- American
1077
00:38:58.239 --> 00:38:58.739
- Elements.
1078
00:38:59.344 --> 00:39:00.484
- Now invent.
1079
00:39:01.824 --> 00:39:04.224
- I'm afraid that's all the time we have
1080
00:39:04.224 --> 00:39:05.525
- for this week's podcast.
1081
00:39:05.984 --> 00:39:08.944
- I'm Hamish Johnston, and our producer is Fred
1082
00:39:08.944 --> 00:39:09.444
- Iles.
1083
00:39:09.904 --> 00:39:12.804
- The music you hear in Physics World's podcasts
1084
00:39:13.130 --> 00:39:15.769
- is called one three seven, and it was
1085
00:39:15.769 --> 00:39:18.349
- composed and performed by the physicist
1086
00:39:18.969 --> 00:39:19.869
- Philip Moriarty.
1087
00:39:20.570 --> 00:39:22.429
- We'll be back again next week.