WEBVTT 1 00:01:53.400 --> 00:01:57.569 Is it any better now? Yes that I can tell. 2 00:01:57.569 --> 00:02:01.019 Okay, beautiful. 3 00:02:05.250 --> 00:02:08.430 Silence. 4 00:02:08.430 --> 00:02:12.449 Silence. 5 00:02:14.699 --> 00:02:25.800 Okay, so final presentations, I'm, I move the group thing to the end because it's a video that I'll show. 6 00:02:25.800 --> 00:02:29.969 Before we go to your presentations, just like to tell you. 7 00:02:29.969 --> 00:02:44.669 Good luck in the future I'm available in the future. I'm even after you leave can discuss any legal and ethical topic doesn't just have to be quantum computing. So it drop me a note. Even after you leave discuss other courses, discuss life in general. 8 00:02:44.669 --> 00:02:49.620 You know, I'm available, but to listen to you, maybe offer advice, but probably not. And also. 9 00:02:49.620 --> 00:02:55.169 Please fill out the course survey that helps me a lot if we get a lot of responses and so on. 10 00:02:55.169 --> 00:03:02.550 Okay, so 1st and John and I'll. 11 00:03:02.550 --> 00:03:09.389 If you can take over, actually share your screen. 12 00:03:09.389 --> 00:03:15.270 If you're here, if not, if you need a few minutes to get started to get set up. 13 00:03:15.270 --> 00:03:21.120 Then, let me know, I. 14 00:03:22.259 --> 00:03:27.060 Yeah, I can see you. 15 00:03:27.060 --> 00:03:30.719 Good, you're sharing your screen, so I'll mute myself now. 16 00:03:40.949 --> 00:03:44.370 All right. Good. 17 00:03:44.370 --> 00:03:47.969 And start off on our research, or. 18 00:03:47.969 --> 00:03:52.110 And I'm John. 19 00:03:52.110 --> 00:03:56.849 Yeah, and, uh, our research is on the fundamentals implementation. 20 00:03:56.849 --> 00:04:00.479 Not only the entire state of events. 21 00:04:00.479 --> 00:04:03.599 Of a trap to on a quantum computer. 22 00:04:05.789 --> 00:04:18.660 So the way we'll be going through this, these are going to start off with how we just like an, in depth overview of our chapter. 9 infrastructure works. It's like how. 23 00:04:18.660 --> 00:04:26.488 What the cubic actually is how would trapping an eye on is the limitation. We're going to go into the stability. 24 00:04:26.488 --> 00:04:30.178 I've turned implementations of time. 25 00:04:30.178 --> 00:04:37.019 Quantum computers, and we're going to go into benchmarking what we came up with to test. 26 00:04:37.019 --> 00:04:40.468 The general state of computers right now. 27 00:04:40.468 --> 00:04:47.819 And then we'll end with that future road map. See on a start. 28 00:04:47.819 --> 00:04:52.288 It's a little bit different of how the cube it's implemented, but. 29 00:04:52.288 --> 00:05:01.949 Say we have these 2 categories, Nashville and artificial cube. It's so we've kind of got hammered home. National Cubics are these phenomenon with. 30 00:05:01.949 --> 00:05:07.798 Articles in elementary article, say, like measuring electrons in and it would have a certain. 31 00:05:07.798 --> 00:05:12.749 State down to the same thing with this. 32 00:05:12.749 --> 00:05:18.119 Elementary particle it's hilarity be horizontal vertical. 33 00:05:18.119 --> 00:05:21.449 For the keep it safe. 34 00:05:21.449 --> 00:05:27.928 However, these these are not easily manipulated or measured, so. 35 00:05:27.928 --> 00:05:31.048 Using, we're still using quantum mechanics. 36 00:05:31.048 --> 00:05:40.228 But say with artificial Cubics, you're doing these macro size processes that still exhibit mechanics, but are actually manipulable and better. 37 00:05:40.228 --> 00:05:44.009 And that's what's going on save for the junction. 38 00:05:44.009 --> 00:05:49.139 Where the quantum dots, and with the assumption on side now. 39 00:05:49.139 --> 00:05:52.978 It's the cubic can actually have multiple. 40 00:05:52.978 --> 00:05:56.249 Um, ways to be measured and set up as a supervision. 41 00:05:56.249 --> 00:06:00.418 That's with respect to charge box space. 42 00:06:00.418 --> 00:06:06.119 It seems the current state of technology there is that. 43 00:06:06.119 --> 00:06:10.499 It's not used as the medium for the cube. 44 00:06:10.499 --> 00:06:15.629 But rather that this phenomenon exhibits different wavelengths. 45 00:06:15.629 --> 00:06:19.048 Which is why it's part of like, a lot of vision technology. 46 00:06:20.548 --> 00:06:25.468 So, the actual cube, it it is that we're using. 47 00:06:25.468 --> 00:06:28.798 Specifically an ion house. 48 00:06:28.798 --> 00:06:31.889 40 C, plus 1 electron is. 49 00:06:31.889 --> 00:06:37.199 And it's superposition is not a factor of spin. 50 00:06:37.199 --> 00:06:40.288 But it's the factor optics so it's an optical Cuban. 51 00:06:41.548 --> 00:06:49.649 So, with this with this paradigm and check when use, but different wavelengths of energy. 52 00:06:49.649 --> 00:06:55.348 Laser light onto this ion, it's free electron space. 53 00:06:55.348 --> 00:06:58.499 Um, orbitals interact in a certain way and. 54 00:06:58.499 --> 00:07:03.358 Okay to other orbitals? No, we'll flip the pointer. 55 00:07:03.358 --> 00:07:06.749 We have over here is, um. 56 00:07:06.749 --> 00:07:11.699 Diagram of how the energy levels are being interacted with. 57 00:07:11.699 --> 00:07:16.918 And with respect to wavelengths, so there's 2 sets the main set. 58 00:07:16.918 --> 00:07:22.139 That is being used, has the advantage of being more stable so. 59 00:07:22.139 --> 00:07:27.749 That's that's noted here and P3 2 the orbital up here. 60 00:07:27.749 --> 00:07:34.978 When it's using that energy level, it's energy level to set the superposition. 61 00:07:34.978 --> 00:07:38.369 So that there is a certain probability. 62 00:07:38.369 --> 00:07:42.269 And then ending up, ending up in the 1 state. 63 00:07:42.269 --> 00:07:48.569 Which is D5 2 and it has another probability of ending in the 0T state. 64 00:07:48.569 --> 00:07:51.718 It's 1 app. 65 00:07:51.718 --> 00:08:01.199 That's that's exactly how superposition is set up for this event and the way it's measured. 66 00:08:01.199 --> 00:08:06.178 We can kind of go into that. 67 00:08:06.178 --> 00:08:11.699 That's part of setting up this queue how to measure and use it everything is that. 68 00:08:11.699 --> 00:08:16.139 These events have to be held in place. 69 00:08:16.139 --> 00:08:19.499 And the way it's set up for. 70 00:08:19.499 --> 00:08:27.389 Now, calcium is that there's 4 electrodes set up in a square configuration. 71 00:08:27.389 --> 00:08:30.809 Well, that's Paul's all strap. So this geometry. 72 00:08:30.809 --> 00:08:35.578 With these pair of charged rods electrical. 73 00:08:35.578 --> 00:08:38.609 Is electrical kind of going through the rods and. 74 00:08:38.609 --> 00:08:43.499 One's posing a negative charge in one's posing a positive charge. 75 00:08:43.499 --> 00:08:49.168 And the pairs, and then they switch so it's constant switching. 76 00:08:49.168 --> 00:08:58.109 Is on the order of, like, radio frequencies so they're switching to positive, negative, positive negative. This is exhibiting electrical field. 77 00:08:58.109 --> 00:09:05.938 Which forces on average the ion, stay in the center of that geometry. 78 00:09:05.938 --> 00:09:12.538 That's that's what keeps the ion stable. 79 00:09:12.538 --> 00:09:15.599 It's not necessary to. 80 00:09:15.599 --> 00:09:20.489 The lasers are for the, with the measurement and the. 81 00:09:20.489 --> 00:09:25.678 The setting up the state, but it's not not for the holding the. 82 00:09:25.678 --> 00:09:34.139 The ions in place now, in order to set all this up in order to create the ion and then bring it into Paul. 83 00:09:34.139 --> 00:09:38.068 On the 1st, it's superheated create. 84 00:09:38.068 --> 00:09:41.099 The calcium. 85 00:09:41.099 --> 00:09:44.668 Nothing and then ways are cool. 86 00:09:44.668 --> 00:09:48.149 Held in place, and then brought over. 87 00:09:48.149 --> 00:09:54.568 Kind of fired is it as it's kind of shown fired over into Paul's trap where, if you're going to be caught. 88 00:09:54.568 --> 00:09:59.038 And the numbers that are going to be caught. 89 00:09:59.038 --> 00:10:03.058 Going to be used as the number of candidates in this whole system. 90 00:10:07.283 --> 00:10:21.234 Okay, so so once our ions are loaded into our trap, uh, we then have to prepare the state into into something that's useful for quantum computation. Uh, so. 91 00:10:22.134 --> 00:10:35.543 As mentioned before we have all these atomic orbitals and different states that are present within our eye on and each of those transitions between states can be uniquely addressed with a different, 92 00:10:35.813 --> 00:10:36.413 um, 93 00:10:36.714 --> 00:10:38.183 wavelength laser polls. 94 00:10:40.073 --> 00:10:40.673 So. 95 00:10:41.129 --> 00:10:47.428 The 1st thing we want to do is prepare all of the ions into a known state. So. 96 00:10:47.428 --> 00:10:51.119 In order to do that, we, we a couple a. 97 00:10:51.119 --> 00:10:56.369 What's called a global addressing beam to the. 98 00:10:56.484 --> 00:11:10.854 The individual ions themselves, which for all ions that are in what's labeled here as as the 0T state, these ions are excited into a short lived auxillary, excited state. 99 00:11:11.124 --> 00:11:20.994 And then that state rapidly mckays down into the lowest orbital, which we, in here, it's labeled as the 1 state. Although the, the choice of. 100 00:11:21.328 --> 00:11:25.259 Which orbitals form the computational basis is somewhat arbitrary. 101 00:11:25.259 --> 00:11:30.389 So, then this, this guarantees that. 102 00:11:30.389 --> 00:11:38.818 All ions, which are already in the 1 state, remain in the 1 state, and all ions, which are initially in the 0T state are now prepared into the 1 state. 103 00:11:38.818 --> 00:11:45.058 So that yeah, sounds so the. 104 00:11:45.058 --> 00:11:59.158 No, no, go back. So, um, so the choice of of which orbitals or which splitting of the orbitals are are used as the basis States dictates what? Pulse. 105 00:11:59.158 --> 00:12:08.818 Energy or pulse of frequency, we use to control the Ion. So typically here, we're, we're talking about optical. 106 00:12:08.818 --> 00:12:11.969 So, these are controlled with optical pulses, but, um. 107 00:12:11.969 --> 00:12:23.099 In general, in practice, the states can be selected such that we can either use megahertz waves or gigahertz waves or low terror hurts waves. 108 00:12:23.099 --> 00:12:26.369 Uh, depending on the energy level, splitting between the different states. 109 00:12:26.369 --> 00:12:34.798 And then and then the detection works on a similar principle. We again illuminate the, the ions with. 110 00:12:34.798 --> 00:12:38.129 A, uh, a global addressing beam this time tuned. 111 00:12:38.129 --> 00:12:42.269 To the wavelength of of this transition between the 1 state. 112 00:12:42.269 --> 00:12:49.739 And now it's an auxiliary excited state used for readout. And so this, this, if. 113 00:12:50.153 --> 00:13:02.604 If an ion is in the 1 state, it becomes excited into the auxillary state, which then rapidly to case back down into the 1 state, and that's emits a photon in the process. So they, they refer to this as a bright transition. 114 00:13:02.994 --> 00:13:06.714 So, if we, if we measure scattered photons from. 115 00:13:07.048 --> 00:13:10.288 The the eye on, then we know that it's in the 1 state. 116 00:13:10.288 --> 00:13:14.759 If we don't measure scattered photons from the ion, then we know that it's in the 0T state. 117 00:13:14.759 --> 00:13:19.859 And typically, both of these processes take approximately less than 1 millisecond. 118 00:13:20.514 --> 00:13:30.323 Next slide so then the actual control of the on itself of the computational basis States is a very similar process. 119 00:13:30.354 --> 00:13:36.683 Except this time we're using a a wavelength that's tuned to the transition between the 1 and the 0T state. 120 00:13:37.019 --> 00:13:49.828 So, whereas in the previous slide, where we're talking about this sort of light, red, global, addressing beam here, now we're talking about those darker red individual, addressing ion beams. 121 00:13:49.828 --> 00:13:53.578 And then by controlling either. 122 00:13:53.964 --> 00:14:03.144 Or some combination of the length, or the amplitude, the frequency, and the polarization of the pulse we control, what type of gate is implemented. 123 00:14:03.323 --> 00:14:09.774 So we control the amount of rotation and the, the angle of rotation between the 0T and 1 States. 124 00:14:10.344 --> 00:14:20.183 So, typically, these these single cube operations are very well defined, and typically, the fidelity is limited by the accuracy and precision of our sources. 125 00:14:20.754 --> 00:14:25.943 So, then maximum fidelity, which has been experimental demonstrated has been 99.999% with 8 times. 126 00:14:25.943 --> 00:14:39.323 Typically, in the range of 1 to 20 micro seconds, and while this 1 to 2000, micro seconds may sound like a very short time. If we compare that to superconducting, which take approximately nanoseconds to implement K times. 127 00:14:39.323 --> 00:14:43.764 It's actually very slow gate time. 128 00:14:43.764 --> 00:14:55.134 If we were to compare this to sort of the analogy of classical computers, superconducting cube, it would be classical computers with clock speeds on the order of gigahertz. Whereas. 129 00:14:58.798 --> 00:15:06.749 Trapped ion Cubics would be like classical computers with clock speeds on the order of hundreds of kilohertz. So it's significantly slower. 130 00:15:07.224 --> 00:15:22.193 And this gate time can be slowed down, but, or it can be shortened. But in general, there's a, there's an inverse correlation between daytime and fidelity. So if we shorten that gay time, we sacrifice some amount of fidelity now in the operation. 131 00:15:23.903 --> 00:15:37.193 Next slide so then the implementation of multi cubic Gates is is slightly more complex than than the implementation of single cubic Gates. 132 00:15:37.734 --> 00:15:45.413 And this complexity often leads to the multi QB Gates being lower fidelity than the single cubic Gates. 133 00:15:46.524 --> 00:15:59.484 So, the Max fidelity, which has been demonstrated with multi cubic Gates and trapped ions is as high as 99.3% and the gay times are typically much longer than the single cubic Gates ranging from 30 to 250 microseconds. 134 00:16:01.859 --> 00:16:07.918 In practice, we typically see fidelity, which is in the range of 96 to 99%. 135 00:16:07.918 --> 00:16:21.869 So the type of multi cubic gate that's implemented in trapped ions is called the gate. It's essentially a controlled Z gate, whereas the common C, not operation is a controlled escape. 136 00:16:21.869 --> 00:16:25.438 So so here we. 137 00:16:25.438 --> 00:16:37.288 In in this schematic, it's shown for just 2 bits of control and a target but because all of all of the ions in the chain can be entangled together. 138 00:16:37.288 --> 00:16:44.428 Uh, this can be extended to any number of Cubics. So, the general idea is that the. 139 00:16:44.428 --> 00:16:51.989 The internal ironic States of the ions themselves are are coupled via the emotional states. 140 00:16:51.989 --> 00:16:56.969 Of the quantum wells induced by the Paul trap so. 141 00:16:56.969 --> 00:17:08.278 We have certain selection rules which are allowed and disallowed based on both the emotional state and the Ionic state of of. 142 00:17:08.278 --> 00:17:11.519 The couple of the ions, so. 143 00:17:11.519 --> 00:17:15.538 By by controlling the length of the pulse. 144 00:17:15.538 --> 00:17:22.318 Uh, and the order that we apply these pulses, uh, we can create and tangling operations between multiple Cuba. 145 00:17:22.824 --> 00:17:29.963 And the net result of that gate is, is shown in the upper right corner. 146 00:17:31.193 --> 00:17:41.753 And so, like I said, this is this is a control Z operation where normally we're used to seeing the controlled not operation, but using well known a quantum circuit identity. 147 00:17:41.753 --> 00:17:51.294 We can actually implement the controlled, not operation using the control Z operation simply by adding to how to mark gates on either side of, of that control to the gate. 148 00:17:51.568 --> 00:17:59.939 Next slide so then it trap systems are. 149 00:17:59.939 --> 00:18:06.778 Most well known for, for being very stable quantum computing modality. 150 00:18:07.523 --> 00:18:21.834 Part of the reason for this is that we're using ions as physical CubeSats. So just to, by the laws of physics, all of these ions will be physically identical. So whereas with with we're. 151 00:18:23.634 --> 00:18:37.943 We have process variations, so each, each cube, it is slightly different and so that requires a very intensive calibration. So for trapped iron quantum computing this, these calibration requirements are are nearly as strict. 152 00:18:38.729 --> 00:18:46.979 But it does, uh, sort of as a double edged sword it, it places very strict requirements on our. 153 00:18:46.979 --> 00:18:51.088 Are sources and detectors we have to be able to very precisely control. 154 00:18:51.088 --> 00:18:58.078 Uh, the, and the stability of our sources, and all of the electric fields, which are used to control these ions. 155 00:18:59.094 --> 00:19:09.114 But the benefit of this system is that we have very long coherence times, so in this diagram on the right this is sort of the basic ironic structure or basic orbital structure of an eye on. 156 00:19:09.564 --> 00:19:17.784 And most commonly, this red quadruple transition is used between the ground state and the orbital. And, uh. 157 00:19:18.118 --> 00:19:28.138 This transition has a very long lifetime of of typically on the order of 3rd, but as long as several seconds, depending on the species used. 158 00:19:28.138 --> 00:19:34.888 Um, and so because of this very long coherence time, even with the longer gate time, we can still fit. 159 00:19:34.888 --> 00:19:49.104 Many more operations into the coherence time of the cube so we can achieve much greater circuit depth as much as some estimates put it at a 1000 times greater than the circuit depth of 160 00:19:49.104 --> 00:19:51.173 superconducting Cubans. 161 00:19:51.479 --> 00:20:03.749 But 1 additional drawback is that the systems are susceptible to unique arrow error channels. 1 of those being the leakage air, which would be. 162 00:20:03.749 --> 00:20:06.929 Uh, the case where we accidentally excite. 163 00:20:06.929 --> 00:20:18.148 The ion into a state, which isn't used as a computational basis. So if in this diagram on the left, if we say, accidentally excited into the P orbital or the f orbital this. 164 00:20:18.148 --> 00:20:23.729 Either of these states aren't used as our computational basis and would not be would not be. 165 00:20:23.729 --> 00:20:31.048 Accurately read out by the readout operations and so we would almost in a way, sort of, sort of lose the information on that. It. 166 00:20:31.673 --> 00:20:36.923 Similarly, we can also physically lose the eye on itself so the on can sort of escape the trap. 167 00:20:37.193 --> 00:20:47.063 If, um, if we don't have a very high quality vacuum on the trapped ions, then extraneous gas particles can collide with ion and essentially knock it out of the trap. 168 00:20:48.743 --> 00:21:02.753 Next slide, so we wanted to compare trapped ion systems to other commercially available superconducting transport systems. So, in order to do this. 169 00:21:03.749 --> 00:21:13.199 We researched 2 benchmarking algorithms, which are commonly used. 1, is the Bernstein algorithm and the other is the hidden shift algorithm. 170 00:21:13.199 --> 00:21:25.469 The Bernstein Rani algorithm, basically in a single shot implements some Oracle function, which is the product of X and some constant and in a single shot, it returns that constant. 171 00:21:25.824 --> 00:21:39.503 Similarly, the head and shift algorithm determines some shift s of some function and again, and returns it in in 1 shot. So both both algorithms have similar outputs. 172 00:21:39.503 --> 00:21:44.423 So the, the results of the 2 can sort of be compared, but they have different circuit requirements. 173 00:21:44.699 --> 00:21:58.193 Uh, so the Bernstein, Ronnie, uh, that we can see on the left requires a high degree of entanglement. So it requires high connectivity from our quantum processor. Whereas the hidden shift algorithm is more of a deeper circuit. 174 00:21:58.193 --> 00:22:02.544 So it requires larger circuit depth and not more operations. 175 00:22:03.023 --> 00:22:16.193 So the Bernstein algorithm favors quantum processors that have a high degree of con activity, whereas the hidden shift algorithm favors quantum processors, which have good circuit depth and that's high fidelity. 176 00:22:18.568 --> 00:22:21.659 Next. 177 00:22:21.659 --> 00:22:21.989 So, 178 00:22:21.983 --> 00:22:22.253 our, 179 00:22:22.253 --> 00:22:28.433 our goal in implementing this benchmarking was to reproduce results from a 2017 paper from ion queue, 180 00:22:28.433 --> 00:22:29.034 where they, 181 00:22:29.034 --> 00:22:36.983 they run these 2 algorithms on an IBM system and their system and and compare the results of the 2. 182 00:22:36.983 --> 00:22:37.074 so. 183 00:22:38.128 --> 00:22:43.739 Sort of as expected the die on queue performs better than. 184 00:22:43.739 --> 00:22:52.828 Then IBM system in the lower left corner or lower right corner here, we can see that the Bernstein files or on a. 185 00:22:52.828 --> 00:23:06.749 Algorithm has around 73% success probability on IBM where it has around 85% success profitability on Q. a corresponding. The, the, the heading shift has around 35% success profitability on IBM. 186 00:23:06.749 --> 00:23:12.028 Whereas, uh, around 77% success probability on on Q. 187 00:23:14.243 --> 00:23:14.604 Excellent. 188 00:23:16.134 --> 00:23:16.673 So here, 189 00:23:17.394 --> 00:23:17.753 we, 190 00:23:18.084 --> 00:23:20.334 we tried to reproduce the results using IQ, 191 00:23:20.364 --> 00:23:28.074 and we actually found the success probability to be slightly better than that demonstrated in on q2017 paper, 192 00:23:28.074 --> 00:23:30.594 which we sort of expect because their, 193 00:23:30.594 --> 00:23:33.983 their hardware has improved over the past 3 years. 194 00:23:33.983 --> 00:23:35.304 So, here we ran. 195 00:23:38.608 --> 00:23:48.509 For the plot on the left is the Bernstein Ronnie output and then the plot on the right is the head and shift output and the X axis is is each different possible. 196 00:23:50.064 --> 00:24:04.253 In this case, it's a, it's a, for Cupid alibre algorithm so each possible Oracle C or each possible hitting shift. S. and so so, in the ideal case, we expect the diagonal matrix to be all ones. 197 00:24:04.733 --> 00:24:13.044 And in fact, we get something very close to that. So, we get around 92% success rate for the Bernstein Ronnie, and around 84% success rate for the head and shift. 198 00:24:14.038 --> 00:24:18.568 So, roughly 6% better than, uh, than what was demonstrated in 17. 199 00:24:19.584 --> 00:24:34.554 And in general, this, this benchmarking really favors on queue because with the trap dial system, we have full activity, whereas with IBM system, we have relatively limited connectivity. 200 00:24:35.548 --> 00:24:38.699 Next. 201 00:24:38.699 --> 00:24:45.269 So, I did the IBM half of the same testing and what happens. 202 00:24:45.269 --> 00:24:48.749 Is that IBM allows you to do more shots? So you can do. 203 00:24:48.749 --> 00:24:52.348 1024 shots I did that for each case as well. 204 00:24:52.348 --> 00:24:57.449 And what's going on for the Bernstein buzzer? Rodney? 205 00:24:57.449 --> 00:25:00.898 And is that the success rate is actually lower than. 206 00:25:00.898 --> 00:25:06.659 What was produced in the paper so that 31% where the paper was at 35%. 207 00:25:06.659 --> 00:25:10.409 And kind of see some of these. 208 00:25:10.409 --> 00:25:14.189 High successes are coordinating, it's like. 209 00:25:14.189 --> 00:25:19.469 The 2nd cubin, um, sometimes shifting so that's what. 210 00:25:19.469 --> 00:25:26.249 Might be might be making an error during the Bernstein or any. 211 00:25:26.249 --> 00:25:32.669 Calculation, um, what's produced on the right the hidden shift benchmarking. 212 00:25:32.669 --> 00:25:39.148 That's kind of par for what happened in the paper, in fact, and prove about 3%. So, this is that. 213 00:25:39.148 --> 00:25:42.778 80% success where the papers around 77. 214 00:25:42.778 --> 00:25:47.429 So it seems like. 215 00:25:47.429 --> 00:25:52.019 They're doing they are improving they are getting a. 216 00:25:52.019 --> 00:25:56.548 Coherent readings when you when you're putting a. 217 00:25:56.548 --> 00:26:00.689 You're putting these on a computer through the algorithm. 218 00:26:00.689 --> 00:26:04.078 But it seems like what we did with. 219 00:26:04.078 --> 00:26:09.838 Star configuration of their key quantum computer. 220 00:26:09.838 --> 00:26:13.648 That did not show significantly better results. 221 00:26:13.648 --> 00:26:17.759 We're putting it through this, the burn steam around. 222 00:26:21.683 --> 00:26:32.153 So, just looking forward to the future of in quantum computing, uh, recently released their roadmap for how they expect to scale their quantum computers. 223 00:26:32.634 --> 00:26:45.834 Um, so they're really looking forward to a fault tolerant error, corrected era of quantum computing. So recently they demonstrated that, um. 224 00:26:46.348 --> 00:26:57.118 They could implement a a single fault tolerant cubic, uh, using a 13 to 1 overhead ratio. So they have 13 physical ions representing 1 error corrected, keep it. 225 00:26:58.104 --> 00:26:58.554 So, 226 00:26:59.814 --> 00:27:00.263 part of this, 227 00:27:00.263 --> 00:27:03.144 is that the very high fidelity of the, 228 00:27:04.584 --> 00:27:09.144 and enables them to have a much lower overhead for error corrections so, 229 00:27:09.144 --> 00:27:13.973 whereas on superconducting where the fidelity is lower, 230 00:27:13.973 --> 00:27:17.903 it's expected that it could have at least a 1000 to 1, 231 00:27:17.933 --> 00:27:22.344 overhead of physical cube to a virtual cube. 232 00:27:22.888 --> 00:27:34.108 So, initially I on Q, expects to scale somewhat slowly and and here on the on this access for. 233 00:27:34.108 --> 00:27:44.848 For the numbers, this is actually the algorithm algorithmic Cubans. So this is sort of analogous to to the virtual key bits. Um. 234 00:27:44.848 --> 00:27:47.939 Represented by many more physical Cupid. 235 00:27:47.939 --> 00:27:51.598 Um, so. 236 00:27:53.213 --> 00:28:07.554 So, they define this algorithm as as sort of the log based to scale representation of the quantum volume. Because their argument is that the way that IBM has defined quantum volume. 237 00:28:07.858 --> 00:28:15.028 It's sort of it's exponentially related to the fidelity of the gates. So if. 238 00:28:15.028 --> 00:28:22.409 If I am keyword to continue using quantum volume very quickly, they would get to sort of absurd numbers of quantum volume there. 239 00:28:22.409 --> 00:28:26.759 They estimate that their upcoming 32 cubic processor. 240 00:28:26.759 --> 00:28:38.189 Would have a quantum volume of around 4M using metric so they, they think that that's sort of an unrealistic representation. So they determine they defined this algorithmic Cuba. 241 00:28:39.804 --> 00:28:52.614 The other thing that they project is to have sort of rack mounted sort of server style data center, quantum computers accessible by 2023 and they think that these rack amount style quantum computers could be used to implement. 242 00:28:54.298 --> 00:29:04.199 Um, sort of meaningful demonstrations of quantum machine learning, uh, as well as leading to a demonstration of quantum advantage or quantum supremacy by 2025. 243 00:29:05.814 --> 00:29:06.173 Excellent. 244 00:29:07.943 --> 00:29:15.503 So the key barriers to realizing the scalability are 1, 245 00:29:15.503 --> 00:29:18.114 obviously improving the quality of the, 246 00:29:19.104 --> 00:29:20.153 the themselves, 247 00:29:20.183 --> 00:29:21.443 even though the quality is very high, 248 00:29:21.443 --> 00:29:23.814 we would like to be as high as physically possible. 249 00:29:24.118 --> 00:29:32.189 So, this relates really to the choice of ions, use the system temperature used the way that the, the different. 250 00:29:32.189 --> 00:29:34.703 orbitals that are used as the computational basis, 251 00:29:34.973 --> 00:29:38.124 and the way that the gates are implemented as a series of pulses, 252 00:29:38.544 --> 00:29:41.183 and specifically relating to the gate implementation, 253 00:29:41.213 --> 00:29:49.884 improving that the gate time while not compromising too much on fidelity will be a a significant endeavor although. 254 00:29:50.189 --> 00:29:56.578 Some areas of research right now, relating to the use of ultra fast optics to control these. 255 00:29:56.578 --> 00:30:07.019 Iot Cubics have demonstrated, or at least suggest that they could get a gay times down to the tens of PCO. 2nd range using ultra fast optical pulses. 256 00:30:07.019 --> 00:30:19.078 And another method to increase the scalability will obviously be to reduce the size of this system. And this will come through the monolithic integration of sources and detectors basically into integrated circuits. 257 00:30:19.078 --> 00:30:33.983 So, they have to integrate all of the voltage and our sources used for the ion trapping as well as the photon sources used for the cooling, the preparation, the read out and the control. All of these would ideally be integrated onto 1, single chip. 258 00:30:35.003 --> 00:30:41.064 Whereas now they're all sort of external sources, which are then coupled into the monolithically integrated ion trap. 259 00:30:41.729 --> 00:30:50.818 Next time. Okay so this is the end of our presentation Thank you for listening and will now answer any questions at this time. 260 00:30:50.818 --> 00:30:54.868 Yeah, thank you very much. I'll start out, so this is. 261 00:30:54.868 --> 00:30:58.229 Sounds like, I am curious leading IBM in the dust. Is that accurate? 262 00:30:59.429 --> 00:31:10.288 Yeah, I mean, I think our results definitely show that 1 of the really strong advantages of or 2 of the really strong advantages of Q is both the high degree of connectivity. 263 00:31:10.288 --> 00:31:21.719 And the superior fidelity, so if you look at a lot of IBM apologies, the connectivity is very limited. I mean, with the superconducting transplants, they can really only get sort of. 264 00:31:21.719 --> 00:31:26.759 Nearest neighbor connectivity, whereas has has full connectivity. 265 00:31:28.409 --> 00:31:38.278 I think that IBM is sort of a little bit more aggressive in their predict projections, whereas ion Q is a very conservative, but. 266 00:31:38.278 --> 00:31:42.239 I think I on Q, at least from the, from the papers that we read. 267 00:31:42.239 --> 00:31:45.959 And the literature review that we did, I think they're. 268 00:31:45.959 --> 00:31:49.798 Their background and foundation foundation is is very solid. 269 00:31:49.798 --> 00:31:54.058 Thank you does anyone else have a question. 270 00:31:56.128 --> 00:32:03.449 Okay, well, thanks again. Oh, there was a question in the chat. I missed it. Connor. 271 00:32:06.538 --> 00:32:12.989 Yeah, I mean, the gate time is definitely a significant challenge. 272 00:32:12.989 --> 00:32:21.058 There are some areas of research. Like I said, in the last slide alter fast optics. 273 00:32:21.058 --> 00:32:24.449 Um, basically using sort of 2nd, Pulse, lasers. 274 00:32:24.449 --> 00:32:29.519 Is is 1 area of research to reduce the gay times. 275 00:32:29.519 --> 00:32:38.068 Um, it's sort of like, the main main pursuit in reducing the gay times, or, at least the only 1 that's really demonstrating results below 1 Micro. 2nd. 276 00:32:38.068 --> 00:32:44.459 So, it's still relatively new and and yet to really prove high fidelity Gates. 277 00:32:44.459 --> 00:32:48.868 But it's definitely it's definitely something that they want to do. 278 00:32:48.868 --> 00:32:54.719 Okay, what else? Okay, thanks again, John and G. 279 00:32:54.719 --> 00:33:00.868 So, are you ready to tell us what you're doing? 280 00:33:00.868 --> 00:33:03.959 Oh, yeah. So can you hear me. 281 00:33:03.959 --> 00:33:08.878 Yes, I can hear you. Okay. So if you can share my screen now. 282 00:33:10.888 --> 00:33:14.459 So, uh. 283 00:33:15.263 --> 00:33:21.894 Good afternoon everyone and my name's you. Hi, and today I'm going to talk about spout more something about the content meaning. 284 00:33:22.374 --> 00:33:23.963 And here's the accountant, 285 00:33:23.993 --> 00:33:33.653 and the 1st part is the background and basic concepts and timelines some algorithms and also the conclusions and the perspectives, 286 00:33:34.134 --> 00:33:35.814 and in this presentation, 287 00:33:35.814 --> 00:33:36.804 both see, 288 00:33:37.314 --> 00:33:41.544 if we're in the high level of quantum willing will be covered. 289 00:33:41.909 --> 00:33:46.558 So, we can see that recently. There's a very fast development in the. 290 00:33:46.884 --> 00:33:52.403 Area of concern computing and the most important 1 is nastier. 291 00:33:52.463 --> 00:34:06.054 Google quantum group announced as he had reached the content supremacy and use the 53 cubic device and for some specific setups or. 292 00:34:06.598 --> 00:34:20.693 Algorithms, whereas are classic computer use, like, 100 years old, 10 sound ears to finish the task while the content computer would only use several minutes. So, it reached that. 293 00:34:20.724 --> 00:34:24.023 So called condom supremacy and also the also tried. 294 00:34:25.378 --> 00:34:28.739 Use the computer to do the chemistry. 295 00:34:28.739 --> 00:34:34.559 Which means to Motors, making themselves advising. 296 00:34:34.559 --> 00:34:36.923 And the successfully Motors process, 297 00:34:37.824 --> 00:34:52.373 and even more recently in this group from China announced and published paper in science saying that they have realized for tonic device contents 298 00:34:52.554 --> 00:34:52.974 missing. 299 00:34:53.724 --> 00:34:59.784 And although they still scramble for tonic device. 300 00:35:00.148 --> 00:35:04.889 But still is kind of a breakthrough. 301 00:35:04.889 --> 00:35:09.239 And for now, the realization of Cuba is are mostly. 302 00:35:09.239 --> 00:35:10.554 Joseph and Johnson, 303 00:35:11.454 --> 00:35:21.954 Joseph jumped in superconducting qbs or the so called transmen and also the chapter line Cupid and in order to realize all those qbrs, 304 00:35:22.764 --> 00:35:30.054 we need to make some control on those cumulus sometimes that we use a field or the electric field. 305 00:35:30.923 --> 00:35:40.434 And we try to manipulate the stadiums. cubeys is sometimes kind of difficult because you can. 306 00:35:40.943 --> 00:35:55.793 It's really hard to exactly control the face of the springs. So this could lead to the arrows in the content system. And this is 1 of the most important challenges for the clinic computing and. 307 00:35:58.014 --> 00:36:11.273 Especially when we try to scare opposite device or try to reach more and more curious, be more and more difficult. So, this mixed scaling of Cape, based a quantum computer parameter now. 308 00:36:11.813 --> 00:36:20.454 So now, scientists and researchers are trying to find some to do is difficulty. 309 00:36:20.514 --> 00:36:35.123 And 1 of them is contaminating and the basic idea of the content naming is to sacrifice University. And so the trait with the so they get the scaling. 310 00:36:35.844 --> 00:36:38.543 And the basic idea is to. 311 00:36:38.878 --> 00:36:50.364 Transform the target program into finding the global mileage state and the problem dealing with C. C. to solve some optimization problem. 312 00:36:50.393 --> 00:37:00.563 The QBO problems kubranetes the quadratic, unconstrained binary optimization problems. And also the. 313 00:37:00.989 --> 00:37:13.318 Content is really closely related to the adobatic quantum computing. So here's a very simple analogy, but explains how it works. 314 00:37:13.318 --> 00:37:19.289 So suppose that we, a person is standing on top of. 315 00:37:19.289 --> 00:37:26.398 Mountain and he's surrounded with valleys and peaks. So the goal of this person is to fight the lowest. 316 00:37:26.398 --> 00:37:29.818 Possible Valley in this area, which so. 317 00:37:29.818 --> 00:37:33.268 This corresponds to finding the minimum. 318 00:37:34.583 --> 00:37:45.534 And, of course, the classical ways to go through all those valleys and heels, and then measure all his rallies and get the final result. 319 00:37:46.463 --> 00:37:56.423 Although it seems to be very tidier space of course, the effective way. But if we have a very narrow problem, and it could cost a lot of time. 320 00:37:56.994 --> 00:38:11.873 So, in the quantum computer, we can make use of their stupid position internally. So, if we have the superposition state, this means that all those different 1 person can coexist in all of those piece. 321 00:38:12.204 --> 00:38:17.873 So, each person will just be responsible for marrying. 322 00:38:18.449 --> 00:38:23.130 Low the near near is valleys. 323 00:38:23.130 --> 00:38:32.070 So, and also we can take, you make use of the which means that a person does now need to just. 324 00:38:32.425 --> 00:38:45.925 Just, as a person can turn us through those heels, but instead of just typing it, so it saves saves time and also it will prevent being trapped into some no commitments. 325 00:38:46.465 --> 00:38:55.974 So, in this 1, in this way, theoretically, we can get content speed up compared to the classroom computer and the content speed up is. 326 00:38:56.039 --> 00:39:00.179 Always refer to a rift reference to the. 327 00:39:00.179 --> 00:39:15.150 Explains your speed up and here's some of the formulations and most of their content meaning devices will use so called model and here's them up. There's a characteristic timescale. 328 00:39:15.150 --> 00:39:21.929 So, Here's some of the key events for the content meaning and. 329 00:39:21.929 --> 00:39:28.440 The idea is proposed 1st, proposed in 9, 8, 8, and. 330 00:39:28.440 --> 00:39:39.389 Uh, the formalization is formed in 98 and the 1st experiment is down in the also in 99 9. 331 00:39:39.389 --> 00:39:47.400 And recently, and from 2007 and 2020, the wave counseling has. 332 00:39:48.025 --> 00:40:01.525 Made a lot of success in this in this area, and they used it created devices for now, the device is up to 5000 Cubans. So it's very amazing. And now we can. 333 00:40:02.670 --> 00:40:06.000 Results devices, so we can try some benchmark. 334 00:40:06.000 --> 00:40:11.909 Algorithms on it is any very convenient. So now we try stand up to. 335 00:40:13.255 --> 00:40:20.635 Algorithms the 1st one's maximum card problem. I think most of you have also tried this in the homework. 336 00:40:21.085 --> 00:40:30.534 So this is the idea is very easy to find a cut who size up top or the total items, at least as charging cards. So we can just. 337 00:40:31.409 --> 00:40:36.480 1st, in the in the bracket. 338 00:40:36.480 --> 00:40:40.260 Final form, we can just create those codes. 339 00:40:40.260 --> 00:40:53.034 And write those the right to use this some of the costs to create the geometry and trying to use both the seminary real device to find the minimal. 340 00:40:53.034 --> 00:41:05.065 And, as a result is, is not very difficult to get the read out. And also the 2nd problem is traveling salesmen problem and. 341 00:41:05.369 --> 00:41:14.909 The idea is to, is that we have a list of points or the subsidies and our goal is to. 342 00:41:15.324 --> 00:41:19.315 Find the shortest possible route that can visit all those cities, 343 00:41:19.315 --> 00:41:20.454 or no, 344 00:41:22.465 --> 00:41:31.344 and we only visit each point only 1 visit only once and we're finding we need to return to the original points. 345 00:41:32.250 --> 00:41:37.409 And Here's some of the formalizations and it, we can see that the. 346 00:41:37.855 --> 00:41:52.135 How many Tony and distant tonia or there is a term called this is this represents the distance between 2 nodes and also we need some constraints because we have to make sure that. 347 00:41:52.860 --> 00:41:56.184 This means that each city will be for polling. 348 00:41:56.184 --> 00:42:07.914 So I'll be visiting owning once and we need to make sure that each position up on the road should only be allocated to owning 1 city or points. 349 00:42:08.965 --> 00:42:23.125 So we can similarly, we can use some codes in best practice platform, a true cradle to cradle the geometry. 350 00:42:23.155 --> 00:42:26.905 And actually, the strong tree is directly obtained from the. 351 00:42:27.210 --> 00:42:30.480 Predefined graph. So. 352 00:42:30.480 --> 00:42:33.570 As here's a. 353 00:42:33.570 --> 00:42:42.030 And to solve this problem, and we can direct a call, the traveling salesman Cubans. 354 00:42:42.030 --> 00:42:50.309 Because it already has a solver when we solve these problems. So we can get a. 355 00:42:50.309 --> 00:43:05.094 For this geometry simulator gives this rays out from the 0T to 3 to 4 to 1 and 2 and we can see that this is exactly the optimal optimal result. 356 00:43:05.125 --> 00:43:20.005 And the total distance, including return is 19, and for the device will get and as a result, actually, 02143 is actually the same result as a simulator. 357 00:43:20.005 --> 00:43:25.014 Just just as a river. It's the reverse of orders. And. 358 00:43:28.530 --> 00:43:40.050 So, we can see that using the WS Bret bracket platform. We can easily program some of those benchmark algorithms. 359 00:43:40.050 --> 00:43:47.820 And it's and also for the simple for those simple questions and problems. 360 00:43:47.820 --> 00:43:56.969 The content only device matters simulator all the real device can always predict the right right. Answer. But however. 361 00:43:56.969 --> 00:44:03.900 It's really hard. We cannot tell you if it's if you have any speed up compared to. 362 00:44:03.900 --> 00:44:09.630 Classic computer, because we our. 363 00:44:09.630 --> 00:44:14.400 But the problem we're interest is very simple. So, in order to. 364 00:44:14.400 --> 00:44:19.440 Exam it, whether or not, we can get quantum speed up. We need to. 365 00:44:19.440 --> 00:44:32.250 And make try to find some more advanced algorithms, and also we need to make the geometry of our network to be much more and more difficult or more complex. 366 00:44:32.250 --> 00:44:43.199 Okay, so to sum up, we can see that in order to develop in order to make the our system. 367 00:44:43.764 --> 00:44:51.445 In order to make the content meaning to be more competitive, but we need to develop some more and Navajo Antonia formulation. 368 00:44:51.835 --> 00:45:02.215 So call now stochastic and also as being how field control masses, and also to improve the superconducting cubes. 369 00:45:02.639 --> 00:45:11.670 And here's some of the references. Okay, that's it. Thank you for your attention and don't hesitate to ask any questions and concerns. 370 00:45:11.670 --> 00:45:15.119 Yeah, thank you very much then. 371 00:45:15.119 --> 00:45:18.329 Laura is open any questions on this. 372 00:45:19.559 --> 00:45:26.099 So they got a lot of potential then D, wave with. 373 00:45:26.099 --> 00:45:35.219 See, how they do to see a contestant from Canada? No, I'm from Canada originally, so okay. 374 00:45:38.039 --> 00:45:51.030 So then the final presentation and, and new SRE, they uploaded it to YouTube and I'll show the YouTube video now. 375 00:45:51.030 --> 00:46:04.469 Silence. 376 00:47:01.224 --> 00:47:04.764 Okay, this is why I have 2 machines running. 377 00:47:05.039 --> 00:47:12.900 I think I'm talking to you on my iPad, because in my laptop just on so. 378 00:47:12.900 --> 00:47:19.320 Give me a minute to see if I can get it going again. So I can run. 379 00:47:19.320 --> 00:47:24.449 You 2. 380 00:47:27.059 --> 00:47:33.059 Key, um, I'm going to see if I can run things from. 381 00:47:33.059 --> 00:47:38.880 The projected from the iPad see, if this works here, just give me a 2nd. 382 00:47:56.190 --> 00:47:59.760 Silence. 383 00:48:20.070 --> 00:48:28.380 Silence. 384 00:48:28.380 --> 00:49:10.079 Silence. 385 00:49:32.099 --> 00:49:37.289 Simulation. 386 00:49:38.849 --> 00:49:44.489 Silence. 387 00:49:50.789 --> 00:50:02.219 Silence. 388 00:50:24.210 --> 00:50:28.079 Silence. 389 00:50:34.710 --> 00:50:51.929 Silence. 390 00:51:36.119 --> 00:51:39.360 Okay, so. 391 00:51:48.989 --> 00:51:54.119 My crime computer's locked up. I don't want to take your time. It would take several minutes to reboot it. 392 00:51:54.119 --> 00:52:00.869 That's my well think pad we're playing the YouTube video through my iPad. 393 00:52:00.869 --> 00:52:04.409 The volume is so low that I can hard to hear it. 394 00:52:04.409 --> 00:52:09.329 And I don't think you can hear it either. So. 395 00:52:09.329 --> 00:52:13.469 I have the link to it online. I'm thinking. 396 00:52:13.469 --> 00:52:18.599 If it's okay with you guys that you can watch it on your own. 397 00:52:18.599 --> 00:52:22.920 And watch it and rewatch it. If you wish. 398 00:52:22.920 --> 00:52:27.239 And that I not take, I not spend a lot of time trying to. 399 00:52:27.239 --> 00:52:32.280 Get it going right now if that sounds reasonable for people. 400 00:52:34.139 --> 00:52:41.429 And if so then this would be the end of the class. 401 00:52:41.429 --> 00:52:45.210 And the end of the course, I'm open, we have some time. 402 00:52:45.210 --> 00:52:51.630 I'm open if we have if anyone has any questions. 403 00:52:51.630 --> 00:52:57.179 And 1 question, I'd like to ask you is how much money did you spend on Amazon? 404 00:52:57.179 --> 00:53:01.019 Was it a trivial amount or a serious amount or. 405 00:53:11.670 --> 00:53:18.119 Okay, dollars photo for. 406 00:53:20.400 --> 00:53:25.289 So, by standards, it was not much okay. 407 00:53:25.289 --> 00:53:28.409 Thank you. I was worried. 408 00:53:29.849 --> 00:53:33.119 Other than that, I encourage you to watch the quantum. 409 00:53:34.590 --> 00:53:45.599 Okay, so please Expander, John 2006 dollars. Okay. 410 00:53:49.530 --> 00:53:53.489 That's like 3 meals or something on the meal plan. 411 00:53:53.489 --> 00:53:58.230 Oh, boy. Okay. That was more. Okay. 412 00:53:59.250 --> 00:54:03.480 Please 1. 413 00:54:03.480 --> 00:54:08.670 Please watch. Okay. 414 00:54:11.369 --> 00:54:14.429 How should we submit the paper? 415 00:54:15.539 --> 00:54:19.320 Well, if it's up to, I don't know. 416 00:54:19.320 --> 00:54:22.559 10 or 20 megabytes email me. 417 00:54:24.659 --> 00:54:28.650 You know, whatever, some 20 megabytes. 418 00:54:30.659 --> 00:54:41.579 Silence whatever. 419 00:54:46.860 --> 00:54:56.369 Silence. 420 00:54:58.920 --> 00:55:02.760 Silence. 421 00:55:07.260 --> 00:55:16.110 Oh. 422 00:55:16.110 --> 00:55:19.199 Let me it was fine. Sure. 423 00:55:22.320 --> 00:55:25.530 Grades go great scope is fine. Um. 424 00:55:26.940 --> 00:55:30.840 I just thought that people might have stuff that wasn't a PDF file or whatever. 425 00:55:30.840 --> 00:55:35.519 Yeah, PDF is preferable actually. 426 00:55:35.519 --> 00:55:41.639 Silence. 427 00:55:41.639 --> 00:55:46.679 Other things quantum computing I'm seeing it in the news now business press. 428 00:55:46.679 --> 00:55:50.550 The Fortune magazine or something, and an article on it. So. 429 00:55:50.550 --> 00:55:55.889 It's getting the attention of people outside the technology companies, so. 430 00:55:59.070 --> 00:56:07.199 Any any other questions or comments on the course. 431 00:56:07.199 --> 00:56:11.070 What would you like to see better next time? So. 432 00:56:11.070 --> 00:56:14.130 Silence. 433 00:56:20.670 --> 00:56:28.170 Any ideas. 434 00:56:30.030 --> 00:56:35.519 Nothing. 435 00:56:39.480 --> 00:56:45.119 Okay, yeah, I. 436 00:56:50.250 --> 00:56:55.409 I'm trying not to overwork you and so. 437 00:56:55.409 --> 00:57:02.309 Thank you. Okay. 438 00:57:04.409 --> 00:57:17.519 Or structure. 439 00:57:17.519 --> 00:57:23.820 On it. 440 00:57:25.619 --> 00:57:31.679 Okay. 441 00:57:40.889 --> 00:57:51.360 More programming site is the. 442 00:58:00.389 --> 00:58:06.869 Good. 443 00:58:15.960 --> 00:58:33.090 Silence. 444 00:58:49.590 --> 00:58:59.639 Silence. 445 00:59:01.409 --> 00:59:12.210 Silence. 446 00:59:18.389 --> 00:59:53.159 Silence. 447 01:00:07.320 --> 01:00:10.769 Silence. 448 01:00:13.199 --> 01:00:31.320 Silence. 449 01:00:39.090 --> 01:00:42.269 Silence. 450 01:01:40.860 --> 01:01:44.309 Silence. 451 01:01:55.619 --> 01:01:59.489 Silence. 452 01:02:04.739 --> 01:02:11.940 Silence. 453 01:03:53.579 --> 01:03:57.389 Silence. 454 01:04:07.289 --> 01:04:11.760 Silence. 455 01:04:13.469 --> 01:04:16.860 Silence. 456 01:04:16.860 --> 01:04:43.590 Silence.