1 00:00:01,639 --> 00:00:05,240 Speaker 1: Hey, welcome to Sign Stuff, a production of iHeartRadio. My 2 00:00:05,320 --> 00:00:07,200 Speaker 1: name is Jorge cham and to the end of the program, 3 00:00:07,280 --> 00:00:10,959 Speaker 1: we are talking about a technology that may potentially impact 4 00:00:11,039 --> 00:00:14,760 Speaker 1: the life of every single human on Earth. It might 5 00:00:14,840 --> 00:00:17,360 Speaker 1: change how we protect data and come up with passwords, 6 00:00:17,480 --> 00:00:20,079 Speaker 1: it might help us make new and exciting materials, and 7 00:00:20,160 --> 00:00:25,560 Speaker 1: it might render cryptocurrencies like bitcoin and dotgecoin totally useless. 8 00:00:26,040 --> 00:00:30,120 Speaker 1: I'm talking about quantum computers. What are they, how do 9 00:00:30,200 --> 00:00:32,559 Speaker 1: they work? And most exciting is that we're going to 10 00:00:32,560 --> 00:00:35,320 Speaker 1: get to visit one of them and actually hear it 11 00:00:35,400 --> 00:00:39,479 Speaker 1: in action. So power up your curiosity, log in, and 12 00:00:39,560 --> 00:00:48,200 Speaker 1: let's answer the question how do quantum computers work? Hey? Everyone? Okay, 13 00:00:48,400 --> 00:00:51,360 Speaker 1: so when I started this episode, I was both terrified 14 00:00:51,560 --> 00:00:55,800 Speaker 1: and excited. Terrified because explaining anything with the word quantum 15 00:00:56,080 --> 00:00:58,960 Speaker 1: is really hard, but excited because I had heard that 16 00:00:59,040 --> 00:01:02,720 Speaker 1: a friend of mine was making quantum computers just ten 17 00:01:02,760 --> 00:01:05,280 Speaker 1: minutes from my house, and this was a great excuse 18 00:01:05,319 --> 00:01:07,240 Speaker 1: for me to go take a look at them. So 19 00:01:07,280 --> 00:01:09,920 Speaker 1: we're going to go see these quantum computers in person 20 00:01:10,200 --> 00:01:12,399 Speaker 1: at the end of the episode, but before that, I 21 00:01:12,400 --> 00:01:14,840 Speaker 1: wanted to make sure that I understood what they were 22 00:01:15,160 --> 00:01:18,280 Speaker 1: how they work, and also what they're potentially going to 23 00:01:18,319 --> 00:01:22,120 Speaker 1: be used for. So this episode is split into three parts. 24 00:01:22,400 --> 00:01:24,679 Speaker 1: What is a quantum computer and how does it work? 25 00:01:25,120 --> 00:01:27,959 Speaker 1: What are quantum computers for? And then we're going to 26 00:01:28,000 --> 00:01:30,240 Speaker 1: go see the quantum computers and we're going to talk 27 00:01:30,240 --> 00:01:32,880 Speaker 1: about how they're made and why they're so hard to 28 00:01:32,920 --> 00:01:35,080 Speaker 1: get them to work. Our guide through all of this 29 00:01:35,280 --> 00:01:37,880 Speaker 1: is going to be my friend who's making the quantum computers, 30 00:01:38,080 --> 00:01:41,559 Speaker 1: Professor Oscar Pater. He's a professor of physics and applied 31 00:01:41,560 --> 00:01:44,960 Speaker 1: physics at Caltech and he's the head of quantum hardware 32 00:01:45,280 --> 00:01:49,680 Speaker 1: for Amazon. He does research on nanophotonics, quantum optics, and 33 00:01:49,760 --> 00:01:54,520 Speaker 1: of course quantum computers. Here's my visit to Oscar Painter's lab. 34 00:02:00,240 --> 00:02:03,000 Speaker 2: Ah, hey, Oscar, how are you good to see you 35 00:02:03,040 --> 00:02:04,040 Speaker 2: after so many years. 36 00:02:04,120 --> 00:02:06,400 Speaker 1: Yeah, it's been a while. Huh yeah, well thanks so 37 00:02:06,480 --> 00:02:07,320 Speaker 1: much for talking with me. 38 00:02:07,480 --> 00:02:10,240 Speaker 3: Yeah, it's been a while. Happy to try to fill 39 00:02:10,280 --> 00:02:11,919 Speaker 3: you in on some of the things we've been doing 40 00:02:11,919 --> 00:02:13,080 Speaker 3: in the areas of quantic computing. 41 00:02:13,880 --> 00:02:15,519 Speaker 1: Okay, so the first thing I wanted to talk to 42 00:02:15,600 --> 00:02:19,200 Speaker 1: him about was just what does the word quantum mean? 43 00:02:19,560 --> 00:02:21,360 Speaker 1: Because I feel like we're going to need that to 44 00:02:21,520 --> 00:02:26,080 Speaker 1: understand what a quantum computer is. Now, the word quantum 45 00:02:26,280 --> 00:02:29,080 Speaker 1: is the word we used to describe how things behave 46 00:02:29,240 --> 00:02:32,200 Speaker 1: at the level of atoms and the tiny little particles 47 00:02:32,240 --> 00:02:35,000 Speaker 1: that make up the atoms. So in our everyday lives, 48 00:02:35,080 --> 00:02:37,800 Speaker 1: we're used to things being solid and us being able 49 00:02:37,840 --> 00:02:39,880 Speaker 1: to hold them, like, for example, if you take a 50 00:02:39,880 --> 00:02:42,240 Speaker 1: piece of wood or a ball. But if you take 51 00:02:42,240 --> 00:02:44,480 Speaker 1: that piece of wood or ball and you chop it up, 52 00:02:44,520 --> 00:02:47,240 Speaker 1: and you keep chopping it up, you get down to atoms, 53 00:02:47,280 --> 00:02:50,120 Speaker 1: and then you'll notice that those atoms don't behave in 54 00:02:50,160 --> 00:02:52,280 Speaker 1: the same way that a piece of wood or a 55 00:02:52,280 --> 00:02:55,679 Speaker 1: ball do. Here's how Oscar explains it. 56 00:02:55,680 --> 00:02:58,640 Speaker 3: It turns out that down to the microscopic scale, so 57 00:02:58,720 --> 00:03:01,399 Speaker 3: not our everyday scale of things, the laws of physics 58 00:03:01,400 --> 00:03:04,600 Speaker 3: that dominate in that regime is quantum mechanics, and quantum 59 00:03:04,600 --> 00:03:07,960 Speaker 3: mechanics is a theory that has some strange attributes that 60 00:03:08,000 --> 00:03:11,600 Speaker 3: we don't experience every day. For example, it postulates that 61 00:03:11,840 --> 00:03:15,480 Speaker 3: things can be in superposition, so you can have objects 62 00:03:15,520 --> 00:03:17,280 Speaker 3: being in sort of what we think of as two 63 00:03:17,280 --> 00:03:20,400 Speaker 3: distinct realities at the same time. Imagine having a particle 64 00:03:20,400 --> 00:03:24,360 Speaker 3: in one position and another position simultaneously. That seems very 65 00:03:24,360 --> 00:03:27,200 Speaker 3: odd to us, but in quantum mechanics it's very natural. 66 00:03:28,080 --> 00:03:30,440 Speaker 1: Like, for example, I grabbed this piece of wood in 67 00:03:30,440 --> 00:03:32,160 Speaker 1: front of me, and it's a piece of wood. It's 68 00:03:32,160 --> 00:03:34,560 Speaker 1: not two things at the same time. Right, It's in 69 00:03:34,600 --> 00:03:35,200 Speaker 1: one location. 70 00:03:35,480 --> 00:03:37,440 Speaker 3: Right, it's sitting there. It's firmly right in front of you. 71 00:03:37,760 --> 00:03:39,280 Speaker 1: Right. If I had an atom in front of me 72 00:03:39,400 --> 00:03:42,520 Speaker 1: or an electron, it wouldn't exactly. 73 00:03:42,520 --> 00:03:44,760 Speaker 3: You would find that if you repeated the measurement or 74 00:03:44,800 --> 00:03:47,960 Speaker 3: finding its position multiple times, you might find that, Oh, 75 00:03:48,000 --> 00:03:50,720 Speaker 3: I get this weird outcome that sometimes I measure it here, 76 00:03:50,760 --> 00:03:53,280 Speaker 3: sometimes I measure it there. And that's because it's actually 77 00:03:53,320 --> 00:03:56,320 Speaker 3: in many places at once, all right, And that's fundamental 78 00:03:56,360 --> 00:03:58,960 Speaker 3: to the description of quantum mechanics. The way I like 79 00:03:58,960 --> 00:04:02,920 Speaker 3: to think about quantum mechanics is really as waves and amplitudes. 80 00:04:03,080 --> 00:04:05,480 Speaker 3: So think about you're at a pond and you throw 81 00:04:05,480 --> 00:04:07,200 Speaker 3: a rock in a pond, and you see this ripple 82 00:04:07,280 --> 00:04:09,840 Speaker 3: of the rock. Right, That's how I think about, Like 83 00:04:09,880 --> 00:04:12,640 Speaker 3: the rocks are sort of the particles, and these wave 84 00:04:12,640 --> 00:04:16,360 Speaker 3: phenomena are sort of the actual physical quantum mechanical description 85 00:04:16,520 --> 00:04:17,400 Speaker 3: of that particle. 86 00:04:18,000 --> 00:04:21,240 Speaker 1: Like the particle the thing, the atom or the electron. 87 00:04:21,400 --> 00:04:23,480 Speaker 1: It's not the rock you throw into the pond, no, 88 00:04:23,520 --> 00:04:25,320 Speaker 1: but it's actually the ripple of the ripple. 89 00:04:25,400 --> 00:04:28,039 Speaker 3: Yeah, that's right, it's this wave. So I may have 90 00:04:28,040 --> 00:04:30,040 Speaker 3: started with something that was very local, like that rock, 91 00:04:30,400 --> 00:04:33,000 Speaker 3: but then it becomes very quickly it sort of propagates 92 00:04:33,000 --> 00:04:35,279 Speaker 3: out and is actually better described as this wave on 93 00:04:35,320 --> 00:04:36,200 Speaker 3: the pond. 94 00:04:36,400 --> 00:04:38,240 Speaker 1: Because like a ripple and a wave in a pond 95 00:04:38,279 --> 00:04:40,320 Speaker 1: like that, it's kind of in a lot of places 96 00:04:40,320 --> 00:04:40,880 Speaker 1: at the same. 97 00:04:40,680 --> 00:04:44,600 Speaker 3: Exactly, that's right. And then the interference is important to understand. 98 00:04:44,640 --> 00:04:46,800 Speaker 3: If I throw two rocks in the pond, then I 99 00:04:46,839 --> 00:04:49,479 Speaker 3: see the sort of interference of the ripple patterns coming 100 00:04:49,480 --> 00:04:51,680 Speaker 3: from each rock that blashed in the pond. 101 00:04:51,480 --> 00:04:54,600 Speaker 1: Right, Like each ripple starts at simple, but then they 102 00:04:54,680 --> 00:04:58,039 Speaker 1: start to mix together and form this complex pattern on 103 00:04:58,080 --> 00:04:59,640 Speaker 1: the surface of the pod. 104 00:05:00,120 --> 00:05:02,839 Speaker 3: Exactly, like how do they evolve in time? 105 00:05:03,880 --> 00:05:06,680 Speaker 1: Okay, so when you get down to the level of atoms, 106 00:05:06,960 --> 00:05:10,880 Speaker 1: things behave really strangely. Scientists think of things at that 107 00:05:11,000 --> 00:05:14,840 Speaker 1: level not as little tiny balls, but as waves or 108 00:05:15,040 --> 00:05:18,120 Speaker 1: ripples of energy, like the ripples in a pond. Now 109 00:05:18,160 --> 00:05:20,240 Speaker 1: you may think, wait a minute, if things are kind 110 00:05:20,240 --> 00:05:23,599 Speaker 1: of wavy and strange at the level of atoms. Why 111 00:05:23,640 --> 00:05:25,640 Speaker 1: isn't it that way when you get to big stuff 112 00:05:25,680 --> 00:05:28,000 Speaker 1: like a piece of wood or a ball, And the 113 00:05:28,120 --> 00:05:31,159 Speaker 1: answer is that they are that way. There's just a 114 00:05:31,279 --> 00:05:34,000 Speaker 1: lot of atoms in a piece of wood, and from 115 00:05:34,040 --> 00:05:37,040 Speaker 1: a distance, it gives you the impression that it's solid. 116 00:05:38,000 --> 00:05:40,880 Speaker 1: It's sort of like how some clouds from afar they 117 00:05:41,040 --> 00:05:43,400 Speaker 1: might look solid once you get up close to them, 118 00:05:43,480 --> 00:05:46,280 Speaker 1: they're actually kind of fuzzy and wispy, and all the 119 00:05:46,320 --> 00:05:49,960 Speaker 1: water droplets are moving around. So that's quantum. Now. A 120 00:05:50,040 --> 00:05:53,680 Speaker 1: quantum computer is what happens when you make a regular computer, 121 00:05:54,200 --> 00:05:57,640 Speaker 1: but you make the circuits out of individual atoms or 122 00:05:57,680 --> 00:05:59,400 Speaker 1: particles like electrons. 123 00:06:00,880 --> 00:06:03,640 Speaker 3: Classical computers are formed from things that are very very 124 00:06:03,640 --> 00:06:04,839 Speaker 3: classical in nature. 125 00:06:04,680 --> 00:06:06,880 Speaker 1: And they uperate kind of on hard switches. 126 00:06:07,080 --> 00:06:09,520 Speaker 3: Yeah, like, yeah, that's right, the transistors on your phone, 127 00:06:09,560 --> 00:06:11,240 Speaker 3: And that's what we call these types of elements. The 128 00:06:11,279 --> 00:06:15,200 Speaker 3: transistors are used to store information or perform calculations, and 129 00:06:15,240 --> 00:06:17,880 Speaker 3: the transistors are really set by a bunch of electrons 130 00:06:18,080 --> 00:06:20,159 Speaker 3: in part of the circuit. And usually you're talking about 131 00:06:20,279 --> 00:06:22,400 Speaker 3: quite a few electrons. 132 00:06:21,960 --> 00:06:25,760 Speaker 1: Because regular transistors are huge. They're bigger than an atom. 133 00:06:25,880 --> 00:06:28,440 Speaker 3: Yes, exactly, that's physically what's going on in your phone. 134 00:06:28,520 --> 00:06:30,680 Speaker 3: And what I'm telling you is that the way to 135 00:06:30,680 --> 00:06:32,960 Speaker 3: think about it is in the quantum case, I just 136 00:06:33,040 --> 00:06:34,200 Speaker 3: have one electron. 137 00:06:34,120 --> 00:06:37,000 Speaker 1: Like the circuits are made out of individual electrons. 138 00:06:37,240 --> 00:06:39,520 Speaker 3: Yeah, atoms is exactly what you're doing. Or a quantum 139 00:06:39,520 --> 00:06:41,880 Speaker 3: particle doesn't have to be electrons, can be other particles. 140 00:06:41,920 --> 00:06:44,440 Speaker 3: That was the sort of very early idea from people 141 00:06:44,440 --> 00:06:46,920 Speaker 3: like FIM and others back in the nineteen eighties is 142 00:06:47,000 --> 00:06:50,159 Speaker 3: if you're going to do this, and you better make 143 00:06:50,240 --> 00:06:52,440 Speaker 3: them out of quantum mechanical objects to begin with. 144 00:06:53,279 --> 00:06:56,120 Speaker 1: Okay, So if you make a computer where the circuits 145 00:06:56,160 --> 00:07:00,640 Speaker 1: are made of individual quantum objects like atoms or electrons, 146 00:07:00,839 --> 00:07:03,520 Speaker 1: then you get a quantum computer. And what that does 147 00:07:03,720 --> 00:07:08,080 Speaker 1: is that it makes their calculations also quantum mechanical. And 148 00:07:08,160 --> 00:07:10,760 Speaker 1: this is where the concept of a cubit comes in. 149 00:07:11,040 --> 00:07:13,840 Speaker 1: It's like a regular bit in your computer, and a 150 00:07:13,840 --> 00:07:16,440 Speaker 1: bit is like a one or zero, but a cubit 151 00:07:16,520 --> 00:07:19,280 Speaker 1: is a quantum mechanical one or zero. 152 00:07:20,880 --> 00:07:23,800 Speaker 3: Classical computers are formed from digital bits and they go 153 00:07:23,960 --> 00:07:28,080 Speaker 3: between one and zero. A quantum computer doesn't have these 154 00:07:28,480 --> 00:07:32,000 Speaker 3: hard zero one states. It has every possibility in between. 155 00:07:32,240 --> 00:07:34,840 Speaker 3: So imagine if we have these two states zero in one. 156 00:07:35,600 --> 00:07:37,440 Speaker 3: I told you that a quantum system can be in 157 00:07:37,520 --> 00:07:40,000 Speaker 3: two different states at once, right, So it can be 158 00:07:40,000 --> 00:07:42,360 Speaker 3: in zero and one at the same time, and I 159 00:07:42,440 --> 00:07:44,720 Speaker 3: can have a different weight of zero or one at 160 00:07:44,720 --> 00:07:46,760 Speaker 3: the same time. It could be ten percent zero, ninety 161 00:07:46,800 --> 00:07:47,280 Speaker 3: percent one. 162 00:07:48,000 --> 00:07:49,280 Speaker 1: It's like a shade of gray. 163 00:07:49,520 --> 00:07:52,720 Speaker 3: Yeah, And so you have all those possibilities in between. 164 00:07:52,800 --> 00:07:55,560 Speaker 3: It can be zero or one or anything in between. 165 00:07:55,960 --> 00:07:58,480 Speaker 1: It can be black, white, dark, gray, light. 166 00:07:58,400 --> 00:08:00,560 Speaker 3: Gray, exactly, So it has all those shape in between. 167 00:08:00,680 --> 00:08:03,120 Speaker 3: You can take zero with some fraction and add it 168 00:08:03,160 --> 00:08:05,600 Speaker 3: to one with any other fraction. You can have any 169 00:08:05,680 --> 00:08:06,440 Speaker 3: combination of that. 170 00:08:07,320 --> 00:08:10,800 Speaker 1: So on a regular computer, if you multiply two bits together, 171 00:08:11,000 --> 00:08:14,760 Speaker 1: it's like you're multiplying two fixed numbers together, like three 172 00:08:14,880 --> 00:08:18,080 Speaker 1: times four. But in a quantum computer, when you multiply 173 00:08:18,160 --> 00:08:21,680 Speaker 1: two cubits together, it's like you're multiplying two things that 174 00:08:21,800 --> 00:08:24,720 Speaker 1: can be lots of numbers at the same time. So, 175 00:08:24,800 --> 00:08:28,160 Speaker 1: for example, it's like you're multiplying every number from zero 176 00:08:28,240 --> 00:08:31,920 Speaker 1: to one hundred times every number from zero to one thousand, 177 00:08:32,240 --> 00:08:36,160 Speaker 1: all at the same time in one operation. That's what 178 00:08:36,240 --> 00:08:39,520 Speaker 1: makes quantum computers unique. They take this weirdness of the 179 00:08:39,640 --> 00:08:43,040 Speaker 1: quantum world and then let's you do math with it. Now, Actually, 180 00:08:43,080 --> 00:08:46,120 Speaker 1: it's not doing all of those multiplications or calculations at 181 00:08:46,120 --> 00:08:49,560 Speaker 1: the same time. It's more like how Oscar described it earlier. 182 00:08:49,840 --> 00:08:52,200 Speaker 1: If you drop two rocks in a pond, you see 183 00:08:52,240 --> 00:08:55,600 Speaker 1: the two ripples spread out and mix together to form 184 00:08:55,679 --> 00:08:59,120 Speaker 1: a complex ripple pattern. That's more of the picture of 185 00:08:59,120 --> 00:09:02,320 Speaker 1: what a quantum comp does. It doesn't do calculations with 186 00:09:02,440 --> 00:09:06,360 Speaker 1: hard numbers. It does calculations with the ripples and patterns 187 00:09:06,400 --> 00:09:10,600 Speaker 1: of quantum numbers. Of course, my next question for Oscar 188 00:09:10,840 --> 00:09:13,600 Speaker 1: was what is that good for? Why would you want 189 00:09:13,640 --> 00:09:16,880 Speaker 1: to do math this way? When we come back, I'm 190 00:09:16,920 --> 00:09:20,240 Speaker 1: going to ask Oscar what quantum computers are for, and 191 00:09:20,280 --> 00:09:22,360 Speaker 1: then at the end we're going to go check out 192 00:09:22,480 --> 00:09:35,160 Speaker 1: the ones he's built. You're listening to sign stuff. Welcome back. Okay, 193 00:09:35,480 --> 00:09:38,000 Speaker 1: to recap, we learned that a quantum computer is a 194 00:09:38,040 --> 00:09:42,320 Speaker 1: regular computer whose circuits are made with individual atoms or 195 00:09:42,320 --> 00:09:45,719 Speaker 1: small particles like electrons, and by doing that you can 196 00:09:45,760 --> 00:09:49,560 Speaker 1: do quantum calculations. That is, you can do math, but 197 00:09:49,640 --> 00:09:52,959 Speaker 1: with numbers that are actually lots of different numbers at 198 00:09:52,960 --> 00:09:55,440 Speaker 1: the same time. So now the question is, why would 199 00:09:55,440 --> 00:09:58,040 Speaker 1: you want to do that? What are quantum computers? Four? 200 00:09:58,520 --> 00:10:02,280 Speaker 1: Here's more of my conversation, but quantum physicist Oscar Painter. 201 00:10:03,640 --> 00:10:05,600 Speaker 1: Let's say it's a few years into the future and 202 00:10:05,640 --> 00:10:08,680 Speaker 1: we have quantum computers, yes, in our phones, like I 203 00:10:08,679 --> 00:10:11,040 Speaker 1: have one in my podget Okay, what can I do 204 00:10:11,080 --> 00:10:12,480 Speaker 1: with it? And how is my life different? 205 00:10:13,840 --> 00:10:15,680 Speaker 3: I think that's a very unlikely scenario. 206 00:10:16,880 --> 00:10:17,320 Speaker 1: Okay. 207 00:10:17,760 --> 00:10:19,440 Speaker 2: I think that's the wrong way. 208 00:10:19,360 --> 00:10:22,480 Speaker 3: To think about how quantic computers might change our lives, 209 00:10:23,600 --> 00:10:26,560 Speaker 3: at least as far as I can project into the future. Okay, 210 00:10:26,880 --> 00:10:28,960 Speaker 3: I think the best way to think about a quantic 211 00:10:29,000 --> 00:10:32,240 Speaker 3: computer as we envision it right now is that it 212 00:10:32,280 --> 00:10:33,400 Speaker 3: will be more. 213 00:10:33,240 --> 00:10:34,640 Speaker 2: Like a supercomputer. 214 00:10:34,920 --> 00:10:37,880 Speaker 3: So a supercomputer is just a very large computer that 215 00:10:38,000 --> 00:10:42,280 Speaker 3: can perform calculations beyond what our desktop, our personal computers 216 00:10:42,320 --> 00:10:45,400 Speaker 3: can do. And these are usually very large, almost building 217 00:10:45,440 --> 00:10:49,319 Speaker 3: scale computers and computer clusters that have many, many different 218 00:10:49,320 --> 00:10:51,839 Speaker 3: processing units that are all integrated together, and through that 219 00:10:51,920 --> 00:10:55,440 Speaker 3: scale you can perform a huge number of computations per 220 00:10:55,480 --> 00:10:58,360 Speaker 3: second and therefore compute some of the hardest problems. 221 00:10:58,000 --> 00:10:58,520 Speaker 2: That are out there. 222 00:10:58,600 --> 00:11:01,360 Speaker 3: A lot of them are used for chemistry problems. They're 223 00:11:01,440 --> 00:11:05,160 Speaker 3: used to study particle physics, so fundamental physics, trying to 224 00:11:05,360 --> 00:11:08,559 Speaker 3: understand models of quantum particles that are beyond the current 225 00:11:08,559 --> 00:11:12,680 Speaker 3: standard model. They're used to compute the properties of materials, 226 00:11:12,920 --> 00:11:14,360 Speaker 3: climate modeling, and things like that. 227 00:11:14,600 --> 00:11:17,120 Speaker 1: So usually science and tech, yeahs, And. 228 00:11:17,120 --> 00:11:19,840 Speaker 3: There's always this competition between different nations who has the 229 00:11:20,000 --> 00:11:22,120 Speaker 3: fastest or the biggest supercomputer. 230 00:11:22,679 --> 00:11:26,240 Speaker 1: I see, So you envision quantum computers will be sort 231 00:11:26,240 --> 00:11:28,360 Speaker 1: of like a specialized version of computer. 232 00:11:28,480 --> 00:11:31,040 Speaker 3: It's going to be some very special type of supercomputer 233 00:11:31,240 --> 00:11:34,360 Speaker 3: that can solve specific problems that quantum computers will be 234 00:11:34,440 --> 00:11:37,600 Speaker 3: very effective at that we can't do today on classic computers, 235 00:11:37,640 --> 00:11:39,640 Speaker 3: no matter how much we scale them up. And the 236 00:11:39,720 --> 00:11:43,319 Speaker 3: key is it's not just a faster supercomputer. It performs 237 00:11:43,360 --> 00:11:46,640 Speaker 3: calculations in a fundamentally different way, and therefore it can 238 00:11:46,679 --> 00:11:49,680 Speaker 3: tackle problems that are possibly outside of the reach of 239 00:11:49,720 --> 00:11:52,120 Speaker 3: these conventional classical supercomputers. 240 00:11:52,440 --> 00:11:54,640 Speaker 1: What do you mean? Out of the reach meaning that. 241 00:11:54,640 --> 00:11:56,760 Speaker 3: No matter how fast they get or how big they get, 242 00:11:56,800 --> 00:11:59,080 Speaker 3: they'll never be able to compute some of these problems, 243 00:11:59,440 --> 00:12:03,319 Speaker 3: never or take an infinite exactly, it's just the scaling 244 00:12:03,400 --> 00:12:06,200 Speaker 3: is so bad for these problems, you would take way 245 00:12:06,240 --> 00:12:10,040 Speaker 3: too long and require way too large on machine. So, 246 00:12:10,080 --> 00:12:13,480 Speaker 3: no matter how hard we work on our current computing technology, 247 00:12:13,880 --> 00:12:16,360 Speaker 3: it has limits and it's known and you can prove 248 00:12:16,360 --> 00:12:20,160 Speaker 3: it for certain problems, and quantic computers when they looked 249 00:12:20,160 --> 00:12:24,800 Speaker 3: at theoretically these same problems, they realize that the same 250 00:12:25,040 --> 00:12:29,240 Speaker 3: restrictions or limitations for quantic computers are not there. There's 251 00:12:29,360 --> 00:12:34,040 Speaker 3: examples where we believe and strongly believe that certain mathematical 252 00:12:34,080 --> 00:12:37,880 Speaker 3: problems that are important are really really hard to perform 253 00:12:38,120 --> 00:12:41,200 Speaker 3: and can't be solved using classical means, no matter how 254 00:12:41,520 --> 00:12:42,720 Speaker 3: much we improve the technology. 255 00:12:42,960 --> 00:12:45,000 Speaker 1: No matter if I have a building full of supercomputers, 256 00:12:45,040 --> 00:12:46,560 Speaker 1: yeah exactly, you'll never be able. 257 00:12:46,400 --> 00:12:48,320 Speaker 3: To just fill the world with them. You still won't 258 00:12:48,360 --> 00:12:51,120 Speaker 3: be able to do it. Yet a quantic computer can 259 00:12:51,160 --> 00:12:52,440 Speaker 3: solve it pretty efficiently. 260 00:12:53,480 --> 00:12:55,640 Speaker 1: Well. Step me through some of these problems. 261 00:12:55,679 --> 00:12:58,560 Speaker 3: Like so the example that everyone points to, and it 262 00:12:58,640 --> 00:13:03,679 Speaker 3: is pretty amazing that people found this, But there's this 263 00:13:03,800 --> 00:13:06,720 Speaker 3: mathematical problem. It just happens to be very applicable to 264 00:13:06,800 --> 00:13:09,400 Speaker 3: our safety or security of our data. So it turns 265 00:13:09,400 --> 00:13:11,959 Speaker 3: out that most of the security of all of the 266 00:13:12,040 --> 00:13:14,920 Speaker 3: data that you hold, all the data that banks or 267 00:13:15,000 --> 00:13:18,080 Speaker 3: various institutions around the world want to be safe and protected, 268 00:13:18,120 --> 00:13:21,319 Speaker 3: they typically encrypt it. And those encryption techniques that have 269 00:13:21,400 --> 00:13:25,280 Speaker 3: been used were what are called RSA encryption, where you 270 00:13:25,360 --> 00:13:27,960 Speaker 3: want to take a large number and understand what its 271 00:13:28,040 --> 00:13:28,880 Speaker 3: prime factors are. 272 00:13:29,840 --> 00:13:32,920 Speaker 1: Okay, so the first big thing that quantum computers can 273 00:13:32,960 --> 00:13:35,720 Speaker 1: be useful, the one that got people really excited about 274 00:13:35,720 --> 00:13:40,360 Speaker 1: them in the nineties, is in breaking password encryption. So 275 00:13:40,520 --> 00:13:43,400 Speaker 1: whenever you enter your password on a website or when 276 00:13:43,400 --> 00:13:47,400 Speaker 1: you download your bank statement, that information is encrypted or 277 00:13:47,440 --> 00:13:51,160 Speaker 1: scrambled so that if anyone happens to catch that information, 278 00:13:51,559 --> 00:13:54,800 Speaker 1: they can't tell what it says. And the whole scheme 279 00:13:55,120 --> 00:13:57,240 Speaker 1: is based on the idea that if I gave you 280 00:13:57,280 --> 00:14:00,600 Speaker 1: a really large number, it's really hard to find what 281 00:14:00,640 --> 00:14:04,640 Speaker 1: its prime factors are. Here's how Oscar explains it, but 282 00:14:04,800 --> 00:14:06,720 Speaker 1: just to give you a quick heads up, a prime 283 00:14:06,800 --> 00:14:09,800 Speaker 1: number is a number that can't be divided except by 284 00:14:09,840 --> 00:14:14,000 Speaker 1: itself or by one. So, for example, thirteen is a 285 00:14:14,000 --> 00:14:17,520 Speaker 1: prime number because you can't fight thirteen by anything except 286 00:14:17,679 --> 00:14:22,360 Speaker 1: thirteen and one, And the same goes for seventeen nineteen 287 00:14:22,600 --> 00:14:26,640 Speaker 1: twenty three and so on. Anyways, here's Oscar explaining it. 288 00:14:27,400 --> 00:14:29,200 Speaker 3: So I give you a number and I say, tell 289 00:14:29,200 --> 00:14:31,600 Speaker 3: me what the prime factors are, and you have to 290 00:14:31,600 --> 00:14:34,600 Speaker 3: break it down to its prime factors. So you know, 291 00:14:34,640 --> 00:14:36,400 Speaker 3: a simple one is, you know, like two, it's just 292 00:14:36,480 --> 00:14:37,920 Speaker 3: one times two, one and two. Those are the two 293 00:14:37,960 --> 00:14:40,240 Speaker 3: prime factors, right. But it gets harder as these numbers 294 00:14:40,280 --> 00:14:40,800 Speaker 3: get bigger. 295 00:14:41,000 --> 00:14:42,880 Speaker 1: If I tell you one millions be round there and 296 00:14:43,000 --> 00:14:44,560 Speaker 1: forty three. 297 00:14:44,040 --> 00:14:50,320 Speaker 3: Yeah, seventeen, very hard to actually answer what those what 298 00:14:50,360 --> 00:14:52,160 Speaker 3: the prime factors are. But if I give you the 299 00:14:52,160 --> 00:14:54,480 Speaker 3: prime factors, you can multiply them together and very quickly 300 00:14:54,520 --> 00:14:56,400 Speaker 3: get the answer to what that larger number is. 301 00:14:56,520 --> 00:14:56,680 Speaker 2: Right. 302 00:14:57,440 --> 00:14:59,280 Speaker 3: And so if you know the prime factors, I can 303 00:14:59,320 --> 00:15:00,600 Speaker 3: give you what they multiply to. 304 00:15:00,920 --> 00:15:01,640 Speaker 2: But if you give me. 305 00:15:01,600 --> 00:15:04,240 Speaker 3: The number that they multiply to without then I have 306 00:15:04,280 --> 00:15:06,640 Speaker 3: a very hard time finding out what the prime factors are. 307 00:15:06,600 --> 00:15:08,720 Speaker 1: Because you'd have to get kind of have to guess. 308 00:15:09,000 --> 00:15:12,520 Speaker 3: Well, you know, there's mathematical techniques to try to find these, 309 00:15:12,520 --> 00:15:13,560 Speaker 3: but they're very inefficient. 310 00:15:14,840 --> 00:15:16,040 Speaker 2: And so it turns. 311 00:15:15,800 --> 00:15:18,560 Speaker 3: Out that most of the security of the way we 312 00:15:18,720 --> 00:15:22,560 Speaker 3: encrypt information is based upon that asymmetry. And how hard 313 00:15:22,560 --> 00:15:23,120 Speaker 3: the problem is. 314 00:15:23,640 --> 00:15:25,880 Speaker 1: So, now, let's say somebody has a quantum computer. 315 00:15:25,760 --> 00:15:29,880 Speaker 3: Right, then they can find those prime factors and they 316 00:15:29,880 --> 00:15:31,520 Speaker 3: can now decrypt all that information. 317 00:15:32,200 --> 00:15:34,800 Speaker 1: They can just grab it from the air, yeah, and 318 00:15:34,840 --> 00:15:35,600 Speaker 1: be like, oh, I know. 319 00:15:35,720 --> 00:15:38,440 Speaker 3: And yeah, I can find the prime factors and then 320 00:15:38,480 --> 00:15:41,600 Speaker 3: I can use that to decrypt the information. 321 00:15:42,000 --> 00:15:43,760 Speaker 1: That would be easy for a quantum computer, and you 322 00:15:43,800 --> 00:15:45,600 Speaker 1: just press a button and will tell you, oh, this 323 00:15:45,760 --> 00:15:48,400 Speaker 1: is an oscar or his secret decoder. 324 00:15:48,600 --> 00:15:53,720 Speaker 3: Yeah, exactly, So that would you know. That obviously concerned 325 00:15:54,000 --> 00:15:57,000 Speaker 3: a lot of people when that algorithm was developed. 326 00:15:58,480 --> 00:16:01,120 Speaker 1: Okay, this gets a little bit heavy into encryption and 327 00:16:01,320 --> 00:16:04,320 Speaker 1: quantum algorithms, but the main point is that most of 328 00:16:04,360 --> 00:16:08,240 Speaker 1: the security of our passwords and our sensitive information, and 329 00:16:08,280 --> 00:16:11,800 Speaker 1: also the encryption of things like bitcoin and all those cryptocurrencies, 330 00:16:12,000 --> 00:16:15,800 Speaker 1: they all depend on this one math problem which is 331 00:16:15,920 --> 00:16:20,000 Speaker 1: really hard for regular computers even supercomputers to solve. And 332 00:16:20,040 --> 00:16:23,400 Speaker 1: that is a problem of finding the two prime numbers 333 00:16:23,440 --> 00:16:27,000 Speaker 1: that multiply to get a really large number. But then 334 00:16:27,040 --> 00:16:30,000 Speaker 1: in nineteen ninety five, a computer scientist named Peter Shore 335 00:16:30,120 --> 00:16:34,240 Speaker 1: publish the paper titled Polynomial time Algorithms for prime factorization 336 00:16:34,280 --> 00:16:37,720 Speaker 1: of discrete logarithms. On a quantum computer, which essentially showed 337 00:16:37,720 --> 00:16:40,200 Speaker 1: that if you have a quantum computer, you can solve 338 00:16:40,200 --> 00:16:42,880 Speaker 1: this problem in a short amount of time. And this 339 00:16:42,960 --> 00:16:45,480 Speaker 1: is probably the main reason that people have been rushing 340 00:16:45,480 --> 00:16:49,240 Speaker 1: to make quantum computers since then, because imagine if everyone 341 00:16:49,280 --> 00:16:53,360 Speaker 1: in the world, people, companies, countries are all protecting their 342 00:16:53,440 --> 00:16:56,440 Speaker 1: secrets using the same trick, but you had a special 343 00:16:56,520 --> 00:16:59,840 Speaker 1: quantum computer that could break that trick, you could rule 344 00:16:59,880 --> 00:17:03,520 Speaker 1: the world. Now, the details of how Peter Shore's algorithm 345 00:17:03,600 --> 00:17:06,119 Speaker 1: works are a little complicated to explain here, but the 346 00:17:06,240 --> 00:17:08,840 Speaker 1: essence of it is that you're using the ripples on 347 00:17:08,920 --> 00:17:12,320 Speaker 1: a pawn nature of quantum numbers on a quantum computer 348 00:17:12,560 --> 00:17:16,560 Speaker 1: to basically try out every possible combination for how to 349 00:17:16,600 --> 00:17:19,840 Speaker 1: break your secret encryption, and you use some clever math 350 00:17:19,920 --> 00:17:23,639 Speaker 1: tricks so that these ripples combine and mix together until 351 00:17:23,680 --> 00:17:26,840 Speaker 1: the right answer pops out. So that is the main 352 00:17:26,880 --> 00:17:30,280 Speaker 1: reason that people are excited about quantum computers. But there 353 00:17:30,320 --> 00:17:34,760 Speaker 1: are other reasons and other possible applications, So here's Oscar 354 00:17:34,920 --> 00:17:36,879 Speaker 1: telling me about them. 355 00:17:37,520 --> 00:17:40,560 Speaker 3: Another example is maybe more natural to think about, and 356 00:17:40,600 --> 00:17:42,600 Speaker 3: this is where quantum computers were first proposed. It to 357 00:17:42,680 --> 00:17:46,080 Speaker 3: be interesting or useful, and that is the simulation of 358 00:17:46,520 --> 00:17:51,040 Speaker 3: nature itself. Nature as we know it is not classical. 359 00:17:51,160 --> 00:17:54,040 Speaker 3: If you peel the layers of the onion enough and 360 00:17:54,080 --> 00:17:56,399 Speaker 3: you get down to the core, right to the atomic scale, 361 00:17:56,400 --> 00:17:59,199 Speaker 3: it turns out that the laws of physics that dominates 362 00:17:59,280 --> 00:18:03,640 Speaker 3: quantum mechanics, okay, like the actual mathematics of that, when 363 00:18:03,640 --> 00:18:06,800 Speaker 3: you describe it, when you have many particles, it quickly 364 00:18:06,840 --> 00:18:09,760 Speaker 3: becomes something that you can't simulate with a classical computer. 365 00:18:10,040 --> 00:18:12,920 Speaker 3: So all those interference of all the particles and keeping 366 00:18:12,960 --> 00:18:14,840 Speaker 3: track of all of that. A classical computer, if you 367 00:18:14,880 --> 00:18:17,240 Speaker 3: try to simulate that, you quickly run out of steam 368 00:18:18,200 --> 00:18:21,840 Speaker 3: and it becomes an exponentially hard problem. And so you know, 369 00:18:21,880 --> 00:18:23,639 Speaker 3: a classical computer is just ill suited. 370 00:18:23,400 --> 00:18:23,840 Speaker 2: To doing that. 371 00:18:24,280 --> 00:18:26,360 Speaker 3: But a quantum computer that's made out of the same 372 00:18:26,480 --> 00:18:29,080 Speaker 3: those sort of particles that can do with that interference naturally, 373 00:18:29,320 --> 00:18:31,520 Speaker 3: you know, has a natural advantage in terms of using 374 00:18:31,560 --> 00:18:34,600 Speaker 3: it to simulate the natural world at its quantum mechanical core. 375 00:18:35,119 --> 00:18:36,080 Speaker 1: Why would I want to do that? 376 00:18:36,440 --> 00:18:38,720 Speaker 3: Yeah, So that's the questions like, okay, so that's great, 377 00:18:38,880 --> 00:18:40,239 Speaker 3: but why would I want to do that other than 378 00:18:40,280 --> 00:18:43,800 Speaker 3: maybe I want to understand physics better? Well, this idea 379 00:18:43,840 --> 00:18:46,240 Speaker 3: that I want to understand how material behaves is a 380 00:18:46,320 --> 00:18:48,679 Speaker 3: very good example. If I'm building an electrical circuit, or 381 00:18:48,720 --> 00:18:52,439 Speaker 3: I'm building a new battery, or I'm building a different 382 00:18:52,600 --> 00:18:55,560 Speaker 3: energy process inside of a material or energy storage device. 383 00:18:55,880 --> 00:18:57,640 Speaker 3: A lot of times that depends on what the electrons 384 00:18:57,640 --> 00:19:01,200 Speaker 3: are doing. If I want to understand or something unique 385 00:19:01,200 --> 00:19:03,920 Speaker 3: when I describe them quantum mechanically, maybe there's special properties 386 00:19:03,920 --> 00:19:06,560 Speaker 3: I'm just totally blind to. So if I wanted to 387 00:19:06,560 --> 00:19:10,320 Speaker 3: make a better superconnecting material, something that can carry electricity 388 00:19:10,400 --> 00:19:15,040 Speaker 3: with no resistance, right, maybe we can have magnetically livitated trains. 389 00:19:15,080 --> 00:19:18,240 Speaker 3: Maybe you can have you know, really efficient electrical circuits 390 00:19:18,240 --> 00:19:19,600 Speaker 3: that don't dissipate any energy. 391 00:19:19,800 --> 00:19:20,600 Speaker 2: All of these things. 392 00:19:20,680 --> 00:19:22,320 Speaker 3: Then I would have to use a quantum computer to 393 00:19:22,359 --> 00:19:23,240 Speaker 3: model that behavior. 394 00:19:23,840 --> 00:19:26,520 Speaker 1: And you said there's some maybe potential applications in chemistry 395 00:19:26,560 --> 00:19:27,160 Speaker 1: and biology. 396 00:19:27,280 --> 00:19:29,120 Speaker 3: Yeah, you know, if I think about what is going 397 00:19:29,160 --> 00:19:32,520 Speaker 3: on when I have a chemical reaction, usually it comes 398 00:19:32,520 --> 00:19:34,680 Speaker 3: down to the electrons, and I need to understand what 399 00:19:34,720 --> 00:19:37,040 Speaker 3: they're doing in order to understand, you know, whether this 400 00:19:37,119 --> 00:19:39,879 Speaker 3: chemical reaction is going to be efficient or not, or 401 00:19:40,000 --> 00:19:42,159 Speaker 3: if I want to describe it with chemical accuracy, so 402 00:19:42,200 --> 00:19:44,320 Speaker 3: I can use it to, you know, do some sort 403 00:19:44,320 --> 00:19:48,439 Speaker 3: of industrial chemical process. The biological application. It's like, if 404 00:19:48,480 --> 00:19:51,200 Speaker 3: I want to know how molecules are biologically relevant molecules 405 00:19:51,200 --> 00:19:54,440 Speaker 3: lined together, then potentially I need to know more information 406 00:19:54,520 --> 00:19:57,520 Speaker 3: about the electronic behavior in these molecules. If I wanted 407 00:19:57,520 --> 00:20:01,240 Speaker 3: to do that without having approximation or much higher accuracy 408 00:20:01,560 --> 00:20:04,080 Speaker 3: than a quantum computer would be potentially more capable. 409 00:20:04,119 --> 00:20:06,560 Speaker 1: There I we might be able to predict better how 410 00:20:06,560 --> 00:20:10,240 Speaker 1: a vaccine will work, or whether a certain chemical introduce 411 00:20:10,240 --> 00:20:11,280 Speaker 1: in your body will. 412 00:20:11,240 --> 00:20:14,400 Speaker 3: Right now, we don't have that sort of level of specificity. 413 00:20:14,400 --> 00:20:16,960 Speaker 3: I mean, we'd love too. People are proposing techniques, but 414 00:20:17,240 --> 00:20:20,360 Speaker 3: that's the right idea, by the devil's in the details. 415 00:20:21,119 --> 00:20:23,080 Speaker 3: And you know, you have people saying, well, look, you know, 416 00:20:23,280 --> 00:20:26,199 Speaker 3: I think even today there's I won't call them skeptics, 417 00:20:26,240 --> 00:20:27,560 Speaker 3: but there's a lot of people that are saying, well, 418 00:20:27,840 --> 00:20:31,199 Speaker 3: I can keep improving my classical algorithms, and whether you 419 00:20:31,200 --> 00:20:33,800 Speaker 3: can really gain advantage from the quantum simulations is a 420 00:20:34,240 --> 00:20:36,960 Speaker 3: it's a practical question, and maybe we don't have as 421 00:20:37,000 --> 00:20:40,119 Speaker 3: clear an example or as clear a win when it 422 00:20:40,160 --> 00:20:42,760 Speaker 3: comes to how quantum computers will will do better, or 423 00:20:42,800 --> 00:20:44,800 Speaker 3: be more efficient, or be able to do the calculations 424 00:20:44,840 --> 00:20:48,080 Speaker 3: fast or even do them ones that the classical computers 425 00:20:48,080 --> 00:20:50,760 Speaker 3: can't do. But I think there's definitely something there. It's 426 00:20:50,800 --> 00:20:52,960 Speaker 3: just that we still have to work on a quantum algorithms. 427 00:20:53,000 --> 00:20:54,360 Speaker 3: It's not as clear cut, I would say. 428 00:20:55,680 --> 00:20:58,919 Speaker 1: So those are the two main applications or uses for 429 00:20:59,080 --> 00:21:03,160 Speaker 1: planted computers. One is in breaking encryption using a special 430 00:21:03,200 --> 00:21:07,160 Speaker 1: algorithm called phase estimation that only works in a quantum computer, 431 00:21:07,359 --> 00:21:11,040 Speaker 1: and the other is to simulate nature, because nature is, 432 00:21:11,160 --> 00:21:14,880 Speaker 1: after all quantum at its core, and so scientists think 433 00:21:14,960 --> 00:21:18,640 Speaker 1: that quantum computers will let us better simulate how atoms 434 00:21:18,640 --> 00:21:22,440 Speaker 1: and electrons interact so that we can design better materials, 435 00:21:22,600 --> 00:21:27,120 Speaker 1: better semiconductors, and maybe better medicines. Now, I said so far, 436 00:21:27,600 --> 00:21:30,600 Speaker 1: because this is all still very new, and there might 437 00:21:30,640 --> 00:21:34,120 Speaker 1: be other classes of problems like the encryption problem where 438 00:21:34,200 --> 00:21:39,120 Speaker 1: quantum computers are just fundamentally and exponentially better at solving, 439 00:21:39,440 --> 00:21:42,840 Speaker 1: but nobody knows for sure. Of course, it's all hinges 440 00:21:42,880 --> 00:21:45,520 Speaker 1: on whether or not we can actually make quantum computers 441 00:21:45,600 --> 00:21:47,919 Speaker 1: at the level that they would actually be useful and 442 00:21:48,160 --> 00:21:51,560 Speaker 1: most important, reliable. So now we're going to go actually 443 00:21:51,600 --> 00:21:54,640 Speaker 1: see these quantum computers that Oscar is building, and he's 444 00:21:54,680 --> 00:21:56,960 Speaker 1: going to tell us why they're hard to make and 445 00:21:57,000 --> 00:22:00,880 Speaker 1: why they're so prone to making errors. But first, let's 446 00:22:00,880 --> 00:22:12,000 Speaker 1: take a quick break. You're listening to science stuff and 447 00:22:12,119 --> 00:22:15,040 Speaker 1: we're back. Well I heard you have a quantum computer 448 00:22:15,080 --> 00:22:15,680 Speaker 1: in your basement. 449 00:22:16,440 --> 00:22:19,640 Speaker 3: Well not in my basement, but in my my laboratory. Yeah, here, 450 00:22:20,440 --> 00:22:21,199 Speaker 3: can we go see it? 451 00:22:21,280 --> 00:22:21,640 Speaker 2: We can? 452 00:22:22,080 --> 00:22:23,280 Speaker 1: Okay, yeah, let's get see it. 453 00:22:23,359 --> 00:22:24,040 Speaker 2: Okay, you want to do that? 454 00:22:24,520 --> 00:22:28,120 Speaker 1: Okay, so where are we going? 455 00:22:28,640 --> 00:22:29,280 Speaker 2: Just the next door. 456 00:22:29,359 --> 00:22:31,320 Speaker 3: We don't actually even have to go down into. 457 00:22:31,040 --> 00:22:33,000 Speaker 2: The basement, into the basement, no. 458 00:22:34,960 --> 00:22:36,000 Speaker 1: Basement sound and more. 459 00:22:36,200 --> 00:22:37,880 Speaker 2: Yeah, i'd scientists exactly. 460 00:22:37,960 --> 00:22:42,520 Speaker 3: So let's all these labs have different variants of quantic 461 00:22:42,560 --> 00:22:47,040 Speaker 3: computers that we're testing. Multiple quantum computers here, yeah, yeah, 462 00:22:47,200 --> 00:22:51,480 Speaker 3: not just one. So there's small scale quantum computers, but 463 00:22:51,520 --> 00:22:55,240 Speaker 3: the largest ones are you know, ones at at Amazon 464 00:22:55,520 --> 00:22:58,000 Speaker 3: or Google or IBM or you know some of the 465 00:22:58,040 --> 00:23:00,280 Speaker 3: other startup companies. These get to be maybe a factor 466 00:23:00,359 --> 00:23:03,080 Speaker 3: of ten times larger than the ones I'll show you. Okay, okay, 467 00:23:03,160 --> 00:23:08,320 Speaker 3: so this gives you an idea. All of these control electronics, 468 00:23:08,480 --> 00:23:11,360 Speaker 3: right is to use to control about twenty of these 469 00:23:11,440 --> 00:23:12,080 Speaker 3: quantum bits. 470 00:23:12,160 --> 00:23:16,159 Speaker 1: There's twenty quantum meaning twenty particle. A machine made up 471 00:23:16,200 --> 00:23:18,800 Speaker 1: of twenty quantum particles. 472 00:23:18,240 --> 00:23:21,720 Speaker 3: Corract right, which we are manipulating as quantum bits, and 473 00:23:21,880 --> 00:23:25,040 Speaker 3: that circuit lives down inside of this special refrigerator. 474 00:23:26,240 --> 00:23:28,840 Speaker 1: Okay, So if you've ever seen, or if you google 475 00:23:28,920 --> 00:23:31,800 Speaker 1: a picture of a quantum computer, most likely what you 476 00:23:31,960 --> 00:23:36,360 Speaker 1: see is something that looks like an upside down metal 477 00:23:36,600 --> 00:23:41,120 Speaker 1: wedding cake with circular tears or platforms that get smaller 478 00:23:41,160 --> 00:23:44,280 Speaker 1: and smaller as they hang down from the ceiling. That 479 00:23:44,400 --> 00:23:49,520 Speaker 1: is basically a super intense refrigerator. The whole purpose of 480 00:23:49,520 --> 00:23:51,640 Speaker 1: it is to get the tip of that upside down 481 00:23:51,840 --> 00:23:54,679 Speaker 1: cake really really really cold. 482 00:23:56,040 --> 00:23:59,480 Speaker 3: And this refrigerator is under vacuum, under high vacuum. It's 483 00:23:59,520 --> 00:24:03,320 Speaker 3: a temperature which is about ten million degrees above absolute zero. 484 00:24:03,560 --> 00:24:04,680 Speaker 2: Ten degrees. 485 00:24:04,760 --> 00:24:06,399 Speaker 3: So to give you an idea, So if I go 486 00:24:06,440 --> 00:24:09,600 Speaker 3: to the deepest part of space, it's a few degrees calvin, 487 00:24:09,760 --> 00:24:12,480 Speaker 3: a few degrees above that food and zero, the coldest 488 00:24:12,560 --> 00:24:15,679 Speaker 3: darkest parts of outer space or that universe. Yeah, but 489 00:24:15,760 --> 00:24:18,439 Speaker 3: this thing's about thirty times colder than that. 490 00:24:18,480 --> 00:24:22,240 Speaker 1: Even WHOA So would you say that some of the 491 00:24:22,280 --> 00:24:24,440 Speaker 1: cold this places in the whole universe. 492 00:24:25,080 --> 00:24:27,480 Speaker 3: I mean no, I mean you can get there's people 493 00:24:27,480 --> 00:24:29,600 Speaker 3: that do this for a living that make really cold things. 494 00:24:29,680 --> 00:24:33,320 Speaker 2: But this is among the very very coldest things. Okay, yeah, 495 00:24:33,359 --> 00:24:34,639 Speaker 2: but this is extremely cold. 496 00:24:34,960 --> 00:24:35,960 Speaker 1: What does it need to be cold? 497 00:24:36,160 --> 00:24:39,639 Speaker 3: Because even the lights, even if we turned all the 498 00:24:39,720 --> 00:24:42,760 Speaker 3: lights off, even just the fact that the room's hot, it's. 499 00:24:42,640 --> 00:24:45,239 Speaker 2: Room temperature, but it radiates. 500 00:24:44,840 --> 00:24:48,840 Speaker 3: Radiation, and that radiation would completely destroy the information in 501 00:24:48,880 --> 00:24:49,359 Speaker 3: the corner bit. 502 00:24:49,520 --> 00:24:51,440 Speaker 2: I see. We have to get it really dark. 503 00:24:51,640 --> 00:24:53,080 Speaker 3: We have to make sure that there's not any of 504 00:24:53,119 --> 00:24:56,080 Speaker 3: this thermal energy that's making it into the circuit, otherwise 505 00:24:56,080 --> 00:24:59,080 Speaker 3: it'll destroy the manipulation of those quantum parties. And so 506 00:24:59,119 --> 00:25:01,159 Speaker 3: it has to be as isolated as we can from 507 00:25:01,200 --> 00:25:03,719 Speaker 3: the environment. We would ideally seal it off from everything, 508 00:25:04,160 --> 00:25:06,640 Speaker 3: so it would be like zero temperature and there would 509 00:25:06,680 --> 00:25:08,720 Speaker 3: be nothing coming in other than what we want to 510 00:25:08,760 --> 00:25:09,800 Speaker 3: send to it to control it. 511 00:25:10,600 --> 00:25:12,720 Speaker 2: And then you can see there's all of these cables, 512 00:25:13,119 --> 00:25:15,080 Speaker 2: uh huh. Each of these feeds. 513 00:25:14,800 --> 00:25:19,400 Speaker 3: Into a microwave cable that could use to control individual 514 00:25:19,680 --> 00:25:21,639 Speaker 3: quantum bits or quantum particles on the circuit. 515 00:25:22,880 --> 00:25:25,639 Speaker 1: So what I'm looking at is a room full of 516 00:25:25,680 --> 00:25:30,000 Speaker 1: electronics and cables, and in the center is a massive 517 00:25:30,080 --> 00:25:34,400 Speaker 1: structure with two suspended eye beams, and hanging from those 518 00:25:34,440 --> 00:25:37,760 Speaker 1: beams is the upside down wedding cake I mentioned before, 519 00:25:38,200 --> 00:25:41,760 Speaker 1: which in this case is sealed inside a really thick 520 00:25:42,040 --> 00:25:45,560 Speaker 1: metal cylinder, and inside that cylinder at the very tip 521 00:25:45,560 --> 00:25:48,880 Speaker 1: of the wedding cake cool to almost the coldest anything 522 00:25:48,920 --> 00:25:51,440 Speaker 1: can be in the whole universe. Is a little chip? 523 00:25:51,520 --> 00:25:53,000 Speaker 1: Good a quantum computer? 524 00:25:54,840 --> 00:25:55,000 Speaker 2: Well? 525 00:25:55,000 --> 00:25:57,240 Speaker 1: What's in there? So describe me what's inside the core 526 00:25:57,280 --> 00:25:58,960 Speaker 1: of it? Is it like a little chip? Yeah? 527 00:25:59,040 --> 00:25:59,280 Speaker 2: Like love. 528 00:26:00,280 --> 00:26:03,800 Speaker 3: It's what's called a superconnecting quantum circuit. So it uses 529 00:26:04,200 --> 00:26:07,119 Speaker 3: little metal traces on a silicon wafer that we pattern 530 00:26:07,280 --> 00:26:09,400 Speaker 3: on the surface, and when you get them cold enough, 531 00:26:09,440 --> 00:26:13,080 Speaker 3: they become super connecting, which means they can carry electrical currents. 532 00:26:12,760 --> 00:26:14,200 Speaker 2: Without any energy dissipation. 533 00:26:14,560 --> 00:26:17,360 Speaker 3: Okay, And it turns out that you can form these 534 00:26:17,400 --> 00:26:20,879 Speaker 3: sort of quantum particles like these atoms, where the current 535 00:26:21,119 --> 00:26:24,000 Speaker 3: is circulating in a clockwise way inside of a little 536 00:26:24,040 --> 00:26:28,160 Speaker 3: tiny ring, or it's circulating counterclockwise, and the clockwise could 537 00:26:28,160 --> 00:26:31,119 Speaker 3: be zero, when the counterclockwise could be one, and you 538 00:26:31,119 --> 00:26:33,800 Speaker 3: can get in any superposition of these two circulation patterns, 539 00:26:33,840 --> 00:26:35,840 Speaker 3: and I can use then I can manipulate what the 540 00:26:35,880 --> 00:26:40,040 Speaker 3: superposition is, and I can have interact with other circulating currents. 541 00:26:40,359 --> 00:26:43,280 Speaker 2: To the things in our circuit. 542 00:26:43,320 --> 00:26:45,800 Speaker 3: There are a few hundred microns in size, so they 543 00:26:45,880 --> 00:26:48,399 Speaker 3: might be a few times the human hair diameter, so 544 00:26:48,440 --> 00:26:53,040 Speaker 3: they're pretty big relative to conventional transistors. It's made out 545 00:26:53,040 --> 00:26:55,639 Speaker 3: of many atoms, but it behaves like a single atom. 546 00:26:55,800 --> 00:26:57,560 Speaker 2: Okay, yeah, the way to think about it. 547 00:26:57,600 --> 00:26:59,320 Speaker 1: So there's like a little array of these things, a. 548 00:26:59,280 --> 00:27:01,879 Speaker 3: Little array of these things on the surface of a microchip, 549 00:27:01,960 --> 00:27:04,399 Speaker 3: and then each of them we can control the current flow. 550 00:27:04,560 --> 00:27:07,000 Speaker 3: So what are called single cubit gates. We bring them 551 00:27:07,040 --> 00:27:08,960 Speaker 3: together and then let them interact them bring them apart. 552 00:27:09,160 --> 00:27:11,120 Speaker 3: So I need to be able to manipulate the single particle, 553 00:27:11,359 --> 00:27:13,400 Speaker 3: put it in any sort of superposition I want. 554 00:27:13,600 --> 00:27:14,840 Speaker 2: And then you have to read out the state of 555 00:27:14,840 --> 00:27:15,640 Speaker 2: these cubits too. 556 00:27:15,720 --> 00:27:17,600 Speaker 3: You have to know after I do my computation, are 557 00:27:17,600 --> 00:27:19,800 Speaker 3: you in state zero or state one? All right, I 558 00:27:19,840 --> 00:27:21,760 Speaker 3: have to ask that question for all my cubits, and 559 00:27:21,760 --> 00:27:22,800 Speaker 3: that will give me the answer. 560 00:27:23,000 --> 00:27:24,760 Speaker 1: I see what is that hearing? 561 00:27:25,040 --> 00:27:28,760 Speaker 3: So this is called the pulse tube cooler sownders sounds 562 00:27:28,800 --> 00:27:30,480 Speaker 3: like if you were ever a kid growing up in 563 00:27:30,520 --> 00:27:33,600 Speaker 3: the eighties and you watch Battlestar Galactica or the Cylons 564 00:27:33,600 --> 00:27:36,320 Speaker 3: and Battlestar Galactica, they do they walk, and they would 565 00:27:36,320 --> 00:27:38,040 Speaker 3: have this flashing light and they'd have this sort of 566 00:27:38,040 --> 00:27:38,920 Speaker 3: sound coming from them. 567 00:27:39,000 --> 00:27:40,240 Speaker 2: This is a similar sort of sound. 568 00:27:40,400 --> 00:27:42,199 Speaker 3: This is a pulse tube cooler and it's shooting a 569 00:27:42,240 --> 00:27:45,720 Speaker 3: slug of helium gas onto a cold plate and then 570 00:27:45,960 --> 00:27:48,480 Speaker 3: in doing so, when it expands, it can cause cooling. 571 00:27:48,680 --> 00:27:51,080 Speaker 3: It's analogous to what you do with the regular refrigerator. 572 00:27:51,440 --> 00:27:53,680 Speaker 3: That's the first stage of cooling, though that only gets 573 00:27:53,720 --> 00:27:56,600 Speaker 3: you down to maybe a tenth of the temperature of 574 00:27:56,640 --> 00:27:58,400 Speaker 3: the room. And then if I want to go even 575 00:27:58,440 --> 00:28:00,600 Speaker 3: cooler down and by another factor of ten or one hundred, 576 00:28:01,000 --> 00:28:03,680 Speaker 3: then you have to use a recirculating gas. 577 00:28:03,960 --> 00:28:06,880 Speaker 2: In this case, it's a dilution fridge that takes mixtures 578 00:28:06,880 --> 00:28:08,040 Speaker 2: of isotopes. 579 00:28:07,560 --> 00:28:10,200 Speaker 3: Of helium helium three and helium four, and when they mix, 580 00:28:10,520 --> 00:28:13,000 Speaker 3: there's an entropy of reaction and that's what gets you 581 00:28:13,040 --> 00:28:14,720 Speaker 3: down to this lowest temperatures I mentioned. 582 00:28:14,880 --> 00:28:18,000 Speaker 1: So it's several stages. Something like take a fridge put 583 00:28:18,000 --> 00:28:19,199 Speaker 1: it inside of another fridge. 584 00:28:19,840 --> 00:28:22,160 Speaker 3: So there's actually like sort of three or four stages 585 00:28:22,400 --> 00:28:23,840 Speaker 3: of if you're inside of a fridge and you have 586 00:28:24,320 --> 00:28:26,880 Speaker 3: instead of the fridge, the one fridge is too hot 587 00:28:26,920 --> 00:28:29,200 Speaker 3: for the other fridge, so we have to isolate them, 588 00:28:29,920 --> 00:28:32,560 Speaker 3: and then we have to do that for every successive stage. 589 00:28:32,680 --> 00:28:34,520 Speaker 1: It's like, if I take my freezer and I put 590 00:28:34,560 --> 00:28:37,320 Speaker 1: it inside of like a restaurant freezer, just be colder. 591 00:28:37,440 --> 00:28:40,160 Speaker 2: Yeah, okay, exactly, I keep doing that. I add, you know, another. 592 00:28:39,920 --> 00:28:43,080 Speaker 1: Way, the fridge inside of my fridge have a restaurant freezer. 593 00:28:42,840 --> 00:28:44,240 Speaker 3: And I keep you know, each of them has the 594 00:28:44,400 --> 00:28:46,760 Speaker 3: ability to get colder and colder. Yeah, So you have 595 00:28:46,800 --> 00:28:48,240 Speaker 3: to do it in stages. Otherwise, if you try to 596 00:28:48,280 --> 00:28:50,000 Speaker 3: do a direct shot, it's too much of a thermal 597 00:28:50,040 --> 00:28:50,760 Speaker 3: load on the system. 598 00:28:50,880 --> 00:28:55,480 Speaker 1: I see. So that's a quantum computer in action. Most 599 00:28:55,520 --> 00:28:57,160 Speaker 1: of what you see when you look at a picture 600 00:28:57,200 --> 00:29:00,320 Speaker 1: of a quantum computer, it's all the machinery needed to 601 00:29:00,400 --> 00:29:03,880 Speaker 1: keep the actual circuit in a near perfect vacuum and 602 00:29:03,920 --> 00:29:06,720 Speaker 1: as cold as possible, and all of that is to 603 00:29:06,840 --> 00:29:11,760 Speaker 1: completely isolate the quantum computer from the outside world. We'll 604 00:29:11,760 --> 00:29:13,240 Speaker 1: get to why you need to do that with a 605 00:29:13,360 --> 00:29:16,160 Speaker 1: quantum computer. But first I was curious how much a 606 00:29:16,240 --> 00:29:21,640 Speaker 1: quantum computer like this costs. Here's what oscars it. Well, 607 00:29:21,640 --> 00:29:23,560 Speaker 1: this is definitely much bigger than my phone. 608 00:29:23,960 --> 00:29:24,800 Speaker 2: Yes, exactly. 609 00:29:24,800 --> 00:29:26,280 Speaker 3: That's why I was saying, you're probably not going to 610 00:29:26,280 --> 00:29:27,440 Speaker 3: carry one of these things around. 611 00:29:27,520 --> 00:29:29,720 Speaker 1: How much is this something like this if I wanted 612 00:29:29,760 --> 00:29:31,040 Speaker 1: to build one in my garage? 613 00:29:31,120 --> 00:29:33,680 Speaker 3: Okay, Well, you know there's always a big difference between 614 00:29:34,040 --> 00:29:37,040 Speaker 3: science money and money that you know, when you're talking 615 00:29:37,040 --> 00:29:39,520 Speaker 3: about conservative products that have large volumes. I remember the 616 00:29:39,520 --> 00:29:42,160 Speaker 3: first time we purchased a big piece of equipment from 617 00:29:42,160 --> 00:29:43,960 Speaker 3: my lab when I was the first a faculty member. 618 00:29:43,960 --> 00:29:44,880 Speaker 2: It was about the same. 619 00:29:45,000 --> 00:29:47,800 Speaker 3: It was about smaller than this thing, so smaller than 620 00:29:47,840 --> 00:29:50,160 Speaker 3: a few cubic feet, but it was more expensive than 621 00:29:50,160 --> 00:29:51,719 Speaker 3: my house when I bought it. 622 00:29:52,120 --> 00:29:54,440 Speaker 2: So there's a big difference. Cot So just keep that 623 00:29:54,480 --> 00:29:54,880 Speaker 2: in mind. 624 00:29:55,280 --> 00:29:57,760 Speaker 3: But one of these systems today, because it's very specialized, 625 00:29:58,120 --> 00:29:59,400 Speaker 3: probably costs about a. 626 00:29:59,360 --> 00:30:00,360 Speaker 2: Million dollars set up. 627 00:30:00,560 --> 00:30:03,240 Speaker 3: Wow, that's another reason why you will probably wont carry 628 00:30:03,240 --> 00:30:06,360 Speaker 3: it around in your pocket any times soon. But it's 629 00:30:06,360 --> 00:30:09,600 Speaker 3: an important actually point to make, is that people will 630 00:30:09,640 --> 00:30:11,680 Speaker 3: build these systems and go to the larger scales. They 631 00:30:11,720 --> 00:30:13,880 Speaker 3: can and spend a lot of money to try to 632 00:30:13,880 --> 00:30:16,600 Speaker 3: do the first demonstrations, but we'll have to shrink them 633 00:30:16,640 --> 00:30:18,600 Speaker 3: and make the more cost effective all the components that 634 00:30:18,640 --> 00:30:18,840 Speaker 3: go in. 635 00:30:18,960 --> 00:30:21,280 Speaker 1: Eventually, it's like we did for any algorithm. 636 00:30:21,400 --> 00:30:24,640 Speaker 3: Yeah, exactly, and that part will happen. It just requires 637 00:30:24,640 --> 00:30:26,920 Speaker 3: you to start building these larger systems and for the 638 00:30:26,960 --> 00:30:29,400 Speaker 3: companies that are making the individual components for them to 639 00:30:29,400 --> 00:30:30,640 Speaker 3: have larger volumes so they can. 640 00:30:30,600 --> 00:30:31,400 Speaker 2: Drive on costs. 641 00:30:31,880 --> 00:30:35,040 Speaker 3: But where it's particularly challenging right now is actually in 642 00:30:35,040 --> 00:30:38,200 Speaker 3: the control electronics. Like the costs about maybe ten thousand 643 00:30:38,240 --> 00:30:39,320 Speaker 3: dollars a little more than ten. 644 00:30:39,240 --> 00:30:42,520 Speaker 2: Thousand dollars just for the control used for every single fewbit. 645 00:30:43,160 --> 00:30:45,400 Speaker 3: Wow, and we need to go to maybe a million 646 00:30:45,480 --> 00:30:48,640 Speaker 3: few bits or something. So that's like ten billion dollars 647 00:30:48,720 --> 00:30:50,560 Speaker 3: just in the control hardware right if we were. 648 00:30:50,480 --> 00:30:51,960 Speaker 2: To scale out what we have today. 649 00:30:52,080 --> 00:30:55,040 Speaker 3: So it's very costly to imagine doing that, so right now, yeah, 650 00:30:55,040 --> 00:30:57,960 Speaker 3: but then we'll get better. We'll do custom silicon chips, 651 00:30:58,000 --> 00:31:00,800 Speaker 3: where the costs are in the scale of the electronics 652 00:31:00,920 --> 00:31:02,520 Speaker 3: is much more efficient, So we'll do what are called 653 00:31:02,560 --> 00:31:06,360 Speaker 3: ASEX or custom circuits that'll drive down costs tremendously, but yeah, 654 00:31:06,360 --> 00:31:08,240 Speaker 3: that that has to happen, but it just you know, 655 00:31:08,280 --> 00:31:09,680 Speaker 3: it's not We're not quite there yet. 656 00:31:11,120 --> 00:31:13,120 Speaker 1: So there you have it. You can build a quantum 657 00:31:13,120 --> 00:31:16,960 Speaker 1: computer in your garage right now for about a million dollars, 658 00:31:17,360 --> 00:31:19,880 Speaker 1: although for that money right now, you could only put 659 00:31:19,920 --> 00:31:23,040 Speaker 1: about twenty cubits on it, which is about as sophisticated 660 00:31:23,160 --> 00:31:28,000 Speaker 1: as an abocus, although this case would be a quantum ebicus. Right. 661 00:31:28,240 --> 00:31:31,200 Speaker 1: The last thing we'll talk about is why quantum computers 662 00:31:31,360 --> 00:31:34,080 Speaker 1: are so hard to make. If they can break any 663 00:31:34,240 --> 00:31:37,040 Speaker 1: encryption on the planet, or potentially let us simulate new 664 00:31:37,080 --> 00:31:40,080 Speaker 1: chemicals and materials, why haven't we done it? What is 665 00:31:40,120 --> 00:31:44,560 Speaker 1: so hard about making a quantum computer? Here's Oscar explaining it. 666 00:31:45,720 --> 00:31:48,280 Speaker 3: Probably the thing that makes it most difficult, and maybe 667 00:31:48,320 --> 00:31:50,960 Speaker 3: it's the most relevant to talk about, is that let's 668 00:31:51,000 --> 00:31:53,520 Speaker 3: say you want to do a computation with a quantum computer, 669 00:31:53,920 --> 00:31:55,880 Speaker 3: and you want to describe it by a certain number 670 00:31:55,880 --> 00:31:57,880 Speaker 3: of particles, and you want to use those particles to 671 00:31:57,920 --> 00:32:01,240 Speaker 3: do your quantum simulation. Then you need to be able 672 00:32:01,240 --> 00:32:03,720 Speaker 3: to control those particles right, to manipulate them to do 673 00:32:03,760 --> 00:32:07,040 Speaker 3: the computation you want. But if those particles interact with 674 00:32:07,080 --> 00:32:10,680 Speaker 3: the environment, then part of the information that you wanted 675 00:32:10,720 --> 00:32:15,160 Speaker 3: to control or manipulate will actually evolve and become connected to. 676 00:32:15,080 --> 00:32:16,120 Speaker 2: These other particles. 677 00:32:16,240 --> 00:32:19,120 Speaker 3: And that's the really tricky problem is how do I 678 00:32:19,160 --> 00:32:23,560 Speaker 3: control tiny little quantum particles with my grubby little hands, 679 00:32:23,640 --> 00:32:25,600 Speaker 3: so to speak. So I have to be able to 680 00:32:25,760 --> 00:32:29,360 Speaker 3: send in these control signals to and manipulate these quantum particles, 681 00:32:29,480 --> 00:32:32,480 Speaker 3: but I can't let in any other parts of the 682 00:32:33,000 --> 00:32:35,760 Speaker 3: environment in the same time, and so it becomes a 683 00:32:35,840 --> 00:32:39,000 Speaker 3: really hard problem to sort of shield the system you're 684 00:32:39,000 --> 00:32:42,040 Speaker 3: trying to use to do this computation, but then also 685 00:32:42,160 --> 00:32:44,000 Speaker 3: allow yourself these control knobs. 686 00:32:44,440 --> 00:32:46,880 Speaker 1: Is it like a question of purity to. 687 00:32:46,880 --> 00:32:49,520 Speaker 3: Some degree, yes, Like the properties electron have to be 688 00:32:50,400 --> 00:32:52,600 Speaker 3: just that electron, and they interact with other things that 689 00:32:52,600 --> 00:32:55,440 Speaker 3: you're not able to control, you lose the information. 690 00:32:56,440 --> 00:32:56,840 Speaker 2: All right. 691 00:32:57,000 --> 00:33:00,160 Speaker 1: So the reason that quantum computers are so hard to 692 00:33:00,200 --> 00:33:04,719 Speaker 1: make and run basically goes back to Schrodinger's cat. Might 693 00:33:04,800 --> 00:33:07,400 Speaker 1: have heard of this analogy when people are talking about 694 00:33:07,480 --> 00:33:09,880 Speaker 1: quantum things, And the idea is that if I take 695 00:33:09,920 --> 00:33:12,360 Speaker 1: a cat and I put it inside a box, and 696 00:33:12,400 --> 00:33:15,840 Speaker 1: I also put in the box a quantum particle that 697 00:33:15,960 --> 00:33:19,120 Speaker 1: might kill the cat. Then when I close the box, 698 00:33:19,600 --> 00:33:23,960 Speaker 1: eventually the cat becomes both alive and dead at the 699 00:33:23,960 --> 00:33:26,640 Speaker 1: same time. And that's because when I close the box, 700 00:33:27,040 --> 00:33:31,040 Speaker 1: the quantumness of that killer particle basically extends to the 701 00:33:31,080 --> 00:33:35,440 Speaker 1: cat itself. Now, a quantum computer is basically like taking 702 00:33:35,520 --> 00:33:38,600 Speaker 1: a whole bunch of those boxes with cats that are 703 00:33:38,640 --> 00:33:41,360 Speaker 1: alive and dead at the same time, and it tries 704 00:33:41,400 --> 00:33:43,920 Speaker 1: to do math with them. And because all those cats 705 00:33:43,960 --> 00:33:47,000 Speaker 1: are in that magical quantum state of being two different 706 00:33:47,040 --> 00:33:49,560 Speaker 1: things at the same time, alive and dead, then you 707 00:33:49,600 --> 00:33:53,520 Speaker 1: can do some really powerful computations with them, like multiply 708 00:33:53,520 --> 00:33:55,760 Speaker 1: a whole bunch of numbers all at the same time. 709 00:33:56,120 --> 00:33:58,520 Speaker 1: But as soon as anyone takes a peek inside one 710 00:33:58,560 --> 00:34:02,000 Speaker 1: of those boxes and the whole thing collapses. As soon 711 00:34:02,040 --> 00:34:04,400 Speaker 1: as you open one box and you see whether the 712 00:34:04,440 --> 00:34:07,440 Speaker 1: cat is alive or dead, then that box loses its 713 00:34:07,640 --> 00:34:10,560 Speaker 1: quantum magic, and all the other boxes that are talking 714 00:34:10,600 --> 00:34:13,560 Speaker 1: to it will also lose their quantum magic. So the 715 00:34:13,600 --> 00:34:16,919 Speaker 1: reason you need to build giant refrigerators and keep these 716 00:34:16,960 --> 00:34:20,680 Speaker 1: computers in an almost perfect vacuum with perfect coldness is 717 00:34:20,719 --> 00:34:23,879 Speaker 1: to protect them from any random bit of motion or 718 00:34:24,080 --> 00:34:28,000 Speaker 1: energy from essentially peeking inside your quantum boxes, because if 719 00:34:28,040 --> 00:34:31,520 Speaker 1: that happens, the whole thing collapses and stops working. And 720 00:34:31,600 --> 00:34:34,280 Speaker 1: this problem only gets worse as you make the computers 721 00:34:34,320 --> 00:34:38,720 Speaker 1: bigger and more complicated. But people like Oscar are getting 722 00:34:38,760 --> 00:34:43,200 Speaker 1: better and better at it. Well, that was great, that 723 00:34:43,280 --> 00:34:45,680 Speaker 1: was awesome. I guess just the last question, what is 724 00:34:45,840 --> 00:34:48,040 Speaker 1: the current state of the art in quantum computers? 725 00:34:48,520 --> 00:34:50,400 Speaker 3: Yeah, so I think that if you can look at 726 00:34:50,400 --> 00:34:52,359 Speaker 3: this on I would say three axis, so you can 727 00:34:52,400 --> 00:34:55,359 Speaker 3: ask how many physical cubits can I make in. 728 00:34:55,320 --> 00:34:56,239 Speaker 1: Control right now? 729 00:34:56,360 --> 00:34:56,520 Speaker 2: Right? 730 00:34:56,600 --> 00:34:58,480 Speaker 1: What's the highest number of somebody that has been So. 731 00:34:58,640 --> 00:35:00,239 Speaker 3: If you just said I just want to be to 732 00:35:00,280 --> 00:35:03,880 Speaker 3: control this many cubits, it's a few hundred. And people 733 00:35:03,920 --> 00:35:07,200 Speaker 3: have made systems of more than a few thousand, but 734 00:35:07,360 --> 00:35:09,799 Speaker 3: maybe not controlled all of them simultaneously. But people have 735 00:35:09,880 --> 00:35:13,080 Speaker 3: definitely made a few hundred and controlled them. So we're 736 00:35:13,120 --> 00:35:15,880 Speaker 3: getting to that level. And you might say, well, okay, 737 00:35:16,600 --> 00:35:19,200 Speaker 3: put that in context, and if we could control them 738 00:35:19,200 --> 00:35:21,680 Speaker 3: with high enough fidelity and not make errors, we would 739 00:35:21,680 --> 00:35:23,480 Speaker 3: be at the point where we could actually start to 740 00:35:23,680 --> 00:35:27,440 Speaker 3: access and solve problems of practical utility better than we 741 00:35:27,520 --> 00:35:29,920 Speaker 3: think other computers can, like we could answer some of 742 00:35:30,000 --> 00:35:33,400 Speaker 3: these questions about how electrons interacted materials, like small toy problems, 743 00:35:33,440 --> 00:35:34,200 Speaker 3: but still useful. 744 00:35:35,160 --> 00:35:38,359 Speaker 1: So like, if I have a thousand cubits working, yeah, 745 00:35:38,440 --> 00:35:40,560 Speaker 1: what kinds of passwords can I break? Right now? 746 00:35:40,840 --> 00:35:41,040 Speaker 2: Yeah? 747 00:35:41,080 --> 00:35:44,000 Speaker 3: So, like the number of bits and an RSA key 748 00:35:44,120 --> 00:35:46,640 Speaker 3: is like a few thousand, So if I had a 749 00:35:46,640 --> 00:35:49,520 Speaker 3: few thousand cubits, I could crack RSA a. 750 00:35:49,520 --> 00:35:52,080 Speaker 1: Few thousand, and we're at one thousand now. Yeah, so 751 00:35:52,200 --> 00:35:55,440 Speaker 1: right now we can maybe crack simple passwords. 752 00:35:55,000 --> 00:35:56,960 Speaker 3: Like yeah, surely that's right, shorter short of ones that 753 00:35:57,000 --> 00:35:59,120 Speaker 3: we can already do classically, So probably not useful, but 754 00:35:59,120 --> 00:36:02,840 Speaker 3: we're within striking. But the bigger problem is that we 755 00:36:02,880 --> 00:36:06,200 Speaker 3: can't do those calculations because our calculations are too air prone. 756 00:36:06,440 --> 00:36:07,920 Speaker 2: Then we need to add the air correction. 757 00:36:08,520 --> 00:36:10,799 Speaker 1: Okay, that's the other that's the root axs. 758 00:36:10,480 --> 00:36:13,120 Speaker 3: And that's adding redundancy, and so really think about it this. 759 00:36:13,280 --> 00:36:16,080 Speaker 3: I need to not have just a few thousand physical cubits, 760 00:36:16,480 --> 00:36:18,759 Speaker 3: but I may need a few million because the redundancy 761 00:36:18,760 --> 00:36:22,560 Speaker 3: factor is pretty large right now, Like if my hardware 762 00:36:22,719 --> 00:36:24,799 Speaker 3: had no errors, I wouldn't need to do any air 763 00:36:24,840 --> 00:36:28,239 Speaker 3: correction and the redundancy factors one. But I do have errors, 764 00:36:28,400 --> 00:36:30,879 Speaker 3: and the errors we have right now require about another 765 00:36:30,920 --> 00:36:36,040 Speaker 3: factor of one thousand overhead a thousand cubits multiple thousands 766 00:36:36,080 --> 00:36:37,640 Speaker 3: of times, so it'd be a thousand times of thousand, 767 00:36:37,680 --> 00:36:40,440 Speaker 3: which is a million. If I need a thousand cubits 768 00:36:40,440 --> 00:36:43,000 Speaker 3: to do computations with, I have to multiply that by 769 00:36:43,000 --> 00:36:45,280 Speaker 3: one thousand, and that gives me how many physical cubits 770 00:36:45,280 --> 00:36:46,080 Speaker 3: I need to represent? 771 00:36:46,320 --> 00:36:47,560 Speaker 2: Oh wow, So. 772 00:36:47,440 --> 00:36:49,160 Speaker 3: That's why I'm saying we probably needed like a million 773 00:36:49,280 --> 00:36:51,560 Speaker 3: physical cubits. So that's what people are doing right now. 774 00:36:51,800 --> 00:36:54,200 Speaker 3: The fact is that we can actually build and control 775 00:36:54,480 --> 00:36:57,359 Speaker 3: on order a few hundred one thousand cubits is amazing, right, 776 00:36:57,560 --> 00:36:58,400 Speaker 3: that's huge progress. 777 00:36:58,480 --> 00:37:00,560 Speaker 1: Like ten years ago it was z there are cubits. 778 00:37:00,640 --> 00:37:03,720 Speaker 3: I would say we became masters of the individual cubit 779 00:37:03,880 --> 00:37:07,200 Speaker 3: so to speak. Maybe even in two thousand we're really 780 00:37:07,280 --> 00:37:09,360 Speaker 3: really good at that. It was very hard to first 781 00:37:09,360 --> 00:37:11,520 Speaker 3: even figure out, like to control a single cubit. But 782 00:37:11,600 --> 00:37:15,040 Speaker 3: since then we've been already growing small cubit systems and 783 00:37:15,120 --> 00:37:17,960 Speaker 3: improving how the interacting in the gates that we can implement. 784 00:37:18,320 --> 00:37:21,399 Speaker 3: There was a recent result where scientists at Google showed 785 00:37:21,400 --> 00:37:25,719 Speaker 3: that their processor would require ten twenty years for a 786 00:37:25,760 --> 00:37:29,640 Speaker 3: classic computer to simulate what they've done the processor. You know, 787 00:37:29,800 --> 00:37:33,200 Speaker 3: our own team hit Amazon. We focused on a slightly 788 00:37:33,239 --> 00:37:37,680 Speaker 3: different hardware implementation that potentially has an ability to reduce 789 00:37:37,760 --> 00:37:40,799 Speaker 3: the hardware overhead by factors on the order five to ten, 790 00:37:40,840 --> 00:37:43,279 Speaker 3: which could be very important. So, even though it doesn't 791 00:37:43,320 --> 00:37:45,319 Speaker 3: have a practical application yet, it's clear like there's a 792 00:37:45,360 --> 00:37:48,719 Speaker 3: big difference in the power of what these things can do. 793 00:37:48,920 --> 00:37:50,800 Speaker 3: There are a set of problems that the class computers 794 00:37:50,800 --> 00:37:51,919 Speaker 3: are just not going to be good at, and there's 795 00:37:51,960 --> 00:37:53,560 Speaker 3: going to be a set of things that quantic computers 796 00:37:53,600 --> 00:37:56,480 Speaker 3: can do that classical ones cannot mimic. And if you're 797 00:37:56,520 --> 00:37:59,240 Speaker 3: watching this as a sort of an interested techy observer 798 00:37:59,520 --> 00:38:01,960 Speaker 3: and look looking for a turning point or a tipping point, 799 00:38:02,040 --> 00:38:04,719 Speaker 3: I'd be watching for how these air rates go down, 800 00:38:04,800 --> 00:38:07,520 Speaker 3: how efficient air correction is in these sort of one 801 00:38:07,560 --> 00:38:10,000 Speaker 3: hundred two thousand cubit systems over the next few years. 802 00:38:10,120 --> 00:38:13,680 Speaker 1: Very cool, Well, thank you so much, Oscar. That was fantastic. 803 00:38:14,120 --> 00:38:17,240 Speaker 3: Yeah, I hope we got into enough of the detail 804 00:38:17,320 --> 00:38:20,920 Speaker 3: where it's understandable enough. It is definitely a difficult subject 805 00:38:21,360 --> 00:38:23,640 Speaker 3: and there's a lot of hype around it. Even for me, 806 00:38:23,719 --> 00:38:26,040 Speaker 3: it's very hard to read the news and to decipher 807 00:38:26,120 --> 00:38:28,319 Speaker 3: what is really an advance of what isn't. And I'm 808 00:38:28,360 --> 00:38:30,640 Speaker 3: deep in the field, so I can only imagine for 809 00:38:30,680 --> 00:38:31,520 Speaker 3: others that read about it. 810 00:38:31,640 --> 00:38:33,200 Speaker 2: Very cool, right, all right? 811 00:38:33,239 --> 00:38:36,160 Speaker 1: Thanks a lot, yep, and that is how a quantum 812 00:38:36,160 --> 00:38:39,319 Speaker 1: computer works. Thanks for going on this field trip with me. 813 00:38:39,480 --> 00:38:44,640 Speaker 1: I hope you enjoyed that. See you next time. You've 814 00:38:44,680 --> 00:38:48,759 Speaker 1: been listening to Science Stuff. Production of iHeartRadio written and 815 00:38:48,760 --> 00:38:52,560 Speaker 1: produced by me or Hitchm executive producer Jerry Rowland, an 816 00:38:52,600 --> 00:38:55,760 Speaker 1: audio engineer and mixer Casey peckrom and you can follow 817 00:38:55,760 --> 00:38:58,800 Speaker 1: me on social media. Just search for PhD comics and 818 00:38:58,880 --> 00:39:01,680 Speaker 1: the name of your favorite Be sure to subscribe to 819 00:39:01,719 --> 00:39:05,040 Speaker 1: Sign Stuff on the iHeartRadio app, Apple Podcasts, or wherever 820 00:39:05,160 --> 00:39:08,279 Speaker 1: you get your podcasts, and please tell your friends We'll 821 00:39:08,320 --> 00:39:15,560 Speaker 1: be back next Wednesday with another episode.