WEBVTT 1 00:00:01.480 --> 00:00:05.599 Welcome to the quark Side. Quantum Physics Podcast, an exploration 2 00:00:05.679 --> 00:00:10.919 of the fundamental structure of reality, where quantum laws govern matter, energy, 3 00:00:11.199 --> 00:00:16.239 and information. Here, uncertainty is a feature, not a flaw, 4 00:00:16.719 --> 00:00:19.239 and understanding begins at the smallest scales. 5 00:00:27.640 --> 00:00:31.960 Happy Valentine's Day. It is Saturday, February fourteenth, twenty twenty six. 6 00:00:32.280 --> 00:00:34.399 And look, I know exactly what you're thinking. 7 00:00:34.439 --> 00:00:35.240 Oh, I think they do two. 8 00:00:35.520 --> 00:00:39.079 You're expecting us to pivot into. I don't know the 9 00:00:39.200 --> 00:00:42.880 chemistry of oxytocin, or maybe the socioeconomic history of the 10 00:00:42.920 --> 00:00:44.560 greeting card industry. 11 00:00:44.240 --> 00:00:47.119 Or maybe why we give people roses which are covered 12 00:00:47.119 --> 00:00:49.039 in thorns. Seems like a mixed. 13 00:00:48.840 --> 00:00:53.759 Message, exactly a thorny flower as the ultimate symbol of affection. 14 00:00:54.280 --> 00:00:58.039 But we are going in a completely completely different direction. 15 00:00:57.759 --> 00:00:59.439 Today, a very very different direction. 16 00:01:00.479 --> 00:01:02.439 While the rest of the world is focusing on love, 17 00:01:02.479 --> 00:01:06.159 we're focusing on something well arguably more fundamental to the 18 00:01:06.200 --> 00:01:08.920 human experience, even if it sounds a lot less romantic. 19 00:01:09.400 --> 00:01:12.040 We are talking about precision, We're talking about order. We 20 00:01:12.120 --> 00:01:14.159 are talking about the ticking of the clock, but not 21 00:01:14.200 --> 00:01:16.680 just any clock. We are diving into a story that 22 00:01:16.760 --> 00:01:21.439 broke well essential yesterday about a strange, complicated, and frankly 23 00:01:21.560 --> 00:01:24.959 mind mending relationship between physics and time itself. 24 00:01:25.159 --> 00:01:28.799 It's a story about order, chaos and a state of 25 00:01:28.840 --> 00:01:32.799 matter that until very recently, and by recently I mean 26 00:01:32.879 --> 00:01:35.519 the last decade, people didn't even think could exist. 27 00:01:35.599 --> 00:01:35.840 Right. 28 00:01:35.920 --> 00:01:38.519 In fact, some very smart people proved it couldn't. 29 00:01:38.159 --> 00:01:39.680 Exist until they were proven wrong. 30 00:01:39.840 --> 00:01:41.159 Until they are proven wrong. 31 00:01:41.120 --> 00:01:45.040 Exactly, we are talking about time crystals. And before you 32 00:01:45.120 --> 00:01:47.680 hit pause or you know, roll your eyes, I need to. 33 00:01:47.680 --> 00:01:49.439 Make a disclaimer necessary one. 34 00:01:49.519 --> 00:01:51.719 No, we are not talking about an infinity stone from 35 00:01:51.760 --> 00:01:54.480 a Marvel movie. We aren't talking about a plot device 36 00:01:54.519 --> 00:01:58.280 from Doctor Who or some mystical New age healing stone 37 00:01:58.319 --> 00:02:00.640 you buy on Etsy to align your chakras. 38 00:02:01.000 --> 00:02:03.120 Although to be fair, the name time crystal does sound 39 00:02:03.159 --> 00:02:04.040 incredibly sci fi. 40 00:02:04.159 --> 00:02:05.480 Oh it's perfect sci fi. 41 00:02:05.640 --> 00:02:07.680 It sounds like something you'd find in a bad paperback 42 00:02:07.719 --> 00:02:09.120 novel from the nineteen seventies. 43 00:02:09.159 --> 00:02:11.560 It sounds totally made up. It sounds like flux capacitor. 44 00:02:11.960 --> 00:02:14.919 But it is hard science. We are talking about a 45 00:02:14.919 --> 00:02:17.360 new state of matter that breaks the rules of how 46 00:02:17.360 --> 00:02:20.520 we think structure and time actually work, and the reason 47 00:02:20.560 --> 00:02:22.319 we are talking about it today is because of our 48 00:02:22.360 --> 00:02:23.360 report that just came out. 49 00:02:23.479 --> 00:02:26.800 That's right. This comes from a report published yesterday February thirteen, 50 00:02:26.879 --> 00:02:30.560 twenty twenty six, on fizz dot org, written by Sam Jarman. 51 00:02:31.280 --> 00:02:34.639 But the core of our discussion, the meat on the bone, 52 00:02:35.039 --> 00:02:38.520 is based on a new study published in Physical Review Letters. 53 00:02:38.560 --> 00:02:41.919 Which, for those who don't follow the academic publishing horse race, 54 00:02:42.319 --> 00:02:44.719 is pretty much the heavy hitter of physics journals. 55 00:02:44.919 --> 00:02:46.000 Oh, it's the top tier. 56 00:02:46.240 --> 00:02:49.120 If you're publishing in PRL, you aren't just speculating, you've 57 00:02:49.120 --> 00:02:50.039 got the receipts. 58 00:02:50.400 --> 00:02:53.080 It is the gold standard. The research was led by 59 00:02:53.159 --> 00:02:57.240 lu Milaviati at the Abdessalam International Center for Theoretical Physics 60 00:02:57.240 --> 00:03:02.039 in Italy, and what they have put for word is well. 61 00:03:01.919 --> 00:03:04.560 It's a blueprint, a blueprint for what exactly. 62 00:03:04.280 --> 00:03:06.360 Or a clock, but not a clock like the one 63 00:03:06.400 --> 00:03:08.360 on your wall or even the one on your phone. 64 00:03:09.039 --> 00:03:12.319 They are proposing a quantum clock built on the backbone 65 00:03:12.560 --> 00:03:13.879 of these time crystals. 66 00:03:13.960 --> 00:03:16.639 So our mission today is to unpack this. We need 67 00:03:16.680 --> 00:03:19.840 to understand what these exotic systems are, and that is 68 00:03:19.879 --> 00:03:22.840 the technical term exotic, which usually means we don't fully 69 00:03:22.960 --> 00:03:23.879 understand it yet. 70 00:03:23.960 --> 00:03:25.439 Right, it's physics code for it. 71 00:03:25.479 --> 00:03:28.400 This is weird and how they could revolutionize everything from 72 00:03:28.439 --> 00:03:31.520 how we navigate the globe to how we detect magnetic fields. 73 00:03:31.800 --> 00:03:35.479 And honestly, it touches on the fundamental limits of quantum mechanics. 74 00:03:36.000 --> 00:03:38.439 It's not just about knowing what time it is. It's 75 00:03:38.439 --> 00:03:41.319 about understanding the nature of time itself and how we 76 00:03:41.400 --> 00:03:44.280 measure it against the background of a chaotic universe. 77 00:03:44.360 --> 00:03:46.560 Okay, that is a big promise. But before we get 78 00:03:46.599 --> 00:03:48.240 to the philosophy, we have to get through the physics. 79 00:03:48.240 --> 00:03:50.000 And I want to do this right. We aren't going 80 00:03:50.039 --> 00:03:51.199 to skim the surface today. 81 00:03:51.280 --> 00:03:52.439 Noh, let's get into the weeds. 82 00:03:52.560 --> 00:03:54.159 We are going to get into the weeds because that's 83 00:03:54.159 --> 00:03:57.039 where the interesting stuff is. So let's start at the 84 00:03:57.080 --> 00:04:01.280 very beginning. The phrase time crystal. It combines two words 85 00:04:01.319 --> 00:04:03.800 we know, but puts them together in a way that 86 00:04:03.960 --> 00:04:05.360 feels wrong. 87 00:04:05.680 --> 00:04:06.599 It does feel wrong. 88 00:04:06.719 --> 00:04:10.960 We know what a crystal is, diamonds, quartz, salt, ice, right, 89 00:04:11.120 --> 00:04:15.000 but when a physicist says crystal, what are they actually defining? 90 00:04:15.080 --> 00:04:17.399 Because I assume they aren't talking about jewelry. 91 00:04:17.600 --> 00:04:20.439 So yeah, let's strip away the aesthetic aspect. Yeah, in 92 00:04:20.480 --> 00:04:23.800 condensed matter physics, A crystal is defined very simply as 93 00:04:23.839 --> 00:04:26.759 a system that breaks spatial translation symmetry. 94 00:04:26.800 --> 00:04:29.560 Okay, you drop the s word early symmetry. We need 95 00:04:29.560 --> 00:04:32.480 to unpack that immediately. What does it mean to break 96 00:04:32.560 --> 00:04:34.240 spatial translation symmetry? 97 00:04:34.439 --> 00:04:38.240 Okay? Imagine you are floating in an infinite empty void, 98 00:04:39.360 --> 00:04:43.800 or simpler, imagine a perfectly smooth, infinite pool of water. 99 00:04:44.319 --> 00:04:47.240 It is completely uniform. Got it. If you close your 100 00:04:47.240 --> 00:04:49.319 eyes and I move you three feet to the left 101 00:04:49.360 --> 00:04:52.279 and you open your eyes, does the world look different, No, it. 102 00:04:52.240 --> 00:04:53.079 Looks exactly the same. 103 00:04:53.120 --> 00:04:57.759 It's just more water exactly. That system has continuous spatial 104 00:04:57.800 --> 00:05:01.240 translation symmetry. The laws of physics and the arrangement of 105 00:05:01.279 --> 00:05:03.879 matter are the same everywhere. It doesn't matter where you are. 106 00:05:04.439 --> 00:05:06.639 But now let's freeze that water into ice. 107 00:05:06.839 --> 00:05:08.439 Okay, so now we have a solid block. 108 00:05:08.839 --> 00:05:11.480 But if you zoom in with a microscope, that ice 109 00:05:11.560 --> 00:05:14.120 isn't smooth anymore. The water molecules have locked into a 110 00:05:14.160 --> 00:05:17.319 rigid lattice structure a pattern. A pattern. Maybe they are 111 00:05:17.399 --> 00:05:20.079 arranged in hexagons. Now, if you stand on a molecule 112 00:05:20.079 --> 00:05:22.519 and I move you a tiny bit to the left, say, 113 00:05:23.000 --> 00:05:25.879 into the empty space between molecules, does the world look different. 114 00:05:26.000 --> 00:05:28.240 Yes, because now I'm not on a molecule anymore. I'm 115 00:05:28.279 --> 00:05:28.759 in the gap. 116 00:05:29.040 --> 00:05:32.240 Correct. But if I move you exactly one lattice unit 117 00:05:32.240 --> 00:05:34.879 to the last ye, the exact distance between two molecules, 118 00:05:34.959 --> 00:05:37.439 you land on another molecule and it looks the same again. 119 00:05:37.680 --> 00:05:41.120 So the symmetry isn't continuous anymore. I can't just move 120 00:05:41.160 --> 00:05:42.879 any distance and have it look the same. 121 00:05:43.160 --> 00:05:43.519 That's it. 122 00:05:43.600 --> 00:05:46.399 I have to move specific, discrete distances to see the 123 00:05:46.480 --> 00:05:47.879 same pattern exactly. 124 00:05:47.920 --> 00:05:50.879 The formation of the crystal has broken the continuous symmetry 125 00:05:50.879 --> 00:05:54.519 of space. It has chosen a specific pattern. It has 126 00:05:54.560 --> 00:05:57.279 imposed order on the chaos. We call this a crystal, 127 00:05:57.720 --> 00:05:59.199 a repeating pattern in space. 128 00:05:59.240 --> 00:06:05.000 Okay, of salt, diamonds, checkerboards, they all break spatial symmetry. Now, 129 00:06:05.040 --> 00:06:07.879 how do we get to a time crystal? Because my 130 00:06:07.920 --> 00:06:10.639 brain wants to imagine a diamond that travels through time, 131 00:06:10.680 --> 00:06:11.680 which I know is wrong. 132 00:06:12.279 --> 00:06:14.160 That is wrong, but it's a fun image. 133 00:06:14.240 --> 00:06:15.160 That is a good image. 134 00:06:15.199 --> 00:06:17.439 No, to understand a time crystal, you have to take 135 00:06:17.439 --> 00:06:20.199 that same logic we just use for space and apply 136 00:06:20.279 --> 00:06:20.839 it to time. 137 00:06:21.399 --> 00:06:23.040 So time has symmetry. 138 00:06:22.720 --> 00:06:26.079 In physics, yes, we have time translation symmetry. It basically 139 00:06:26.079 --> 00:06:27.920 means that the laws of physics don't care when you 140 00:06:28.000 --> 00:06:31.000 run an experiment. If you mix baking soda and vinegar 141 00:06:31.040 --> 00:06:33.800 today at noon, it bubbles. If you do it tomorrow 142 00:06:33.839 --> 00:06:36.639 at midnight, it bawls. The same way. The laws are 143 00:06:36.639 --> 00:06:40.279 constant in time, energy is conserved, the system is stable. 144 00:06:40.439 --> 00:06:43.959 Okay, So breaking that symmetry would mean what that the 145 00:06:44.040 --> 00:06:45.279 laws of physics change. 146 00:06:45.879 --> 00:06:48.399 Not that the laws change, but that the system itself 147 00:06:48.560 --> 00:06:52.120 refuses to be constant in time. It means that even 148 00:06:52.120 --> 00:06:55.360 in its lowest energy state, its most comfortable rested state, 149 00:06:56.160 --> 00:06:58.240 it is changing. It is moving. 150 00:06:58.560 --> 00:07:01.240 Okay, let's unpack that sattern repeating in time. 151 00:07:01.560 --> 00:07:04.399 Imagine a material that, instead of looking the same, if 152 00:07:04.399 --> 00:07:05.920 you look three inches to the left, it. 153 00:07:05.879 --> 00:07:07.600 Looks the same if you look three seconds later. 154 00:07:07.680 --> 00:07:10.480 That's exactly it. It has a configuration that oscillates, it 155 00:07:10.519 --> 00:07:13.560 returns to its original state. It fixed intervals. It has 156 00:07:13.600 --> 00:07:17.319 a temporal structure. It effectively creates its own timeline. Tick 157 00:07:17.639 --> 00:07:18.399 tick tick. 158 00:07:18.519 --> 00:07:20.600 But wait, I have to play the skeptic here. Isn't 159 00:07:20.639 --> 00:07:24.560 that just anything that moves like a clock pendulum repeats 160 00:07:24.600 --> 00:07:28.000 in time? My heart beats in time. The turn signal 161 00:07:28.000 --> 00:07:30.480 on my car repeats in time. Why are those not 162 00:07:30.759 --> 00:07:33.519 time crystals? Why do we need a fancy new term 163 00:07:33.560 --> 00:07:34.240 for vibration. 164 00:07:34.480 --> 00:07:37.240 That is the million dollar question, and this is where 165 00:07:37.279 --> 00:07:40.160 it gets subtle and where we have to talk about thermodynamics. 166 00:07:40.439 --> 00:07:43.600 A pendulum, a heart, a turn signal. They all need 167 00:07:43.720 --> 00:07:46.759 energy to keep going. They need fuel. If you stop 168 00:07:46.800 --> 00:07:50.319 winding the Grandfather clock, the pendulum stops because of friction 169 00:07:50.360 --> 00:07:53.240 and air resistance. If you stop powering the turn signal, 170 00:07:53.439 --> 00:07:56.680 the light goes off. They are constantly losing energy to heat. 171 00:07:57.360 --> 00:08:00.879 They eventually wind down to a stop to equilibrit Right. 172 00:08:01.279 --> 00:08:03.519 Entropy comes for us. All the universe wants to be 173 00:08:03.560 --> 00:08:04.560 a lukewarm soup. 174 00:08:05.240 --> 00:08:08.879 Ideally, yes, yeah. In a standard system, the ground state, 175 00:08:09.120 --> 00:08:11.759 the state of lowest energy, where the system settles when 176 00:08:11.800 --> 00:08:14.199 you take away all the heat and excitement. Is static. 177 00:08:14.360 --> 00:08:17.279 It's motionless, a rock sitting at the bottom of a hill. 178 00:08:17.439 --> 00:08:19.680 But for a time crystal. You're saying, the ground state 179 00:08:19.720 --> 00:08:20.720 itself is moving. 180 00:08:20.839 --> 00:08:25.160 Precisely, a time crystal exhibits this repeating motion, this oscillation 181 00:08:25.759 --> 00:08:29.839 in its lowest possible energy state. It's not moving because 182 00:08:29.839 --> 00:08:32.480 you are pushing it. No external force, no external force. 183 00:08:32.639 --> 00:08:35.399 It's moving, because movement is its natural state of being. 184 00:08:35.799 --> 00:08:38.759 It breaks time translation symmetry spontaneously. 185 00:08:39.080 --> 00:08:43.000 WHOA stop there. You just described a system that moves 186 00:08:43.000 --> 00:08:45.559 forever in its ground state without energy input. 187 00:08:45.639 --> 00:08:45.919 I did. 188 00:08:46.000 --> 00:08:49.480 That sounds suspiciously like a perpetual motion machine. And the 189 00:08:49.559 --> 00:08:52.440 last time I checked, the first law of filmodynamics says 190 00:08:52.720 --> 00:08:55.559 no free lunch. Why isn't this violating physics? 191 00:08:55.600 --> 00:08:57.120 I love that you went there, because that was the 192 00:08:57.159 --> 00:09:02.120 exact controversy when this was first proposed. Image Nobel laureate 193 00:09:02.159 --> 00:09:06.240 Frank Wilchek propose this idea around twenty twelve, he asked, 194 00:09:06.440 --> 00:09:09.440 can a system break time symmetry the way a crystal 195 00:09:09.480 --> 00:09:12.759 breaks space symmetry? And the initial reaction for the community 196 00:09:12.879 --> 00:09:16.759 was basically, Frank, You've lost it. That's perpetual motion. 197 00:09:17.279 --> 00:09:19.639 So how is it not? How does it get around that? 198 00:09:19.759 --> 00:09:22.960 Because of the definition of work, A perpetual motion machine 199 00:09:23.000 --> 00:09:25.919 is impossible because it claims you can extract energy from 200 00:09:25.919 --> 00:09:26.720 it forever. 201 00:09:26.919 --> 00:09:28.320 Right, you can power something with it. 202 00:09:28.360 --> 00:09:30.399 You can hook it up to a turbine and power 203 00:09:30.440 --> 00:09:32.759 a light bulb a time crystal cannot do that? 204 00:09:32.799 --> 00:09:35.240 Why not? If it's moving, surely I can hook a 205 00:09:35.279 --> 00:09:35.759 gear to it. 206 00:09:35.879 --> 00:09:38.559 No, because the system is in its ground state, it 207 00:09:38.600 --> 00:09:41.000 has no excess energy to give you. If you try 208 00:09:41.000 --> 00:09:43.159 to hook a gear to it, you are interacting with it. 209 00:09:43.559 --> 00:09:47.360 You're adding resistance that collapses the quantum state. The moment 210 00:09:47.399 --> 00:09:51.000 you try to extract work, the time crystal breaks, it 211 00:09:51.080 --> 00:09:53.879 stops being a time crystal. So it moves forever, but 212 00:09:54.000 --> 00:09:56.080 it's useless for powering your car. 213 00:09:56.240 --> 00:09:57.320 So it's a closed loop. 214 00:09:57.360 --> 00:10:00.639 It's closed loop. It violates no laws because it generates 215 00:10:00.639 --> 00:10:01.159 no power. 216 00:10:01.279 --> 00:10:03.960 It's like a ghost pacing in a hallway. It's moving, 217 00:10:04.120 --> 00:10:05.440 but it can't turn a doorknob. 218 00:10:05.639 --> 00:10:10.600 That is a surprisingly accurate analogy. Yes, a perfect frictionless ghost. 219 00:10:10.799 --> 00:10:15.919 Okay, So Willcheck proposes this in twenty twelve, everyone says, maybe, 220 00:10:16.639 --> 00:10:18.799 then what happened because you mentioned we've known they exist 221 00:10:18.919 --> 00:10:19.679 for a decade. 222 00:10:19.759 --> 00:10:22.799 Well, there was a bit of drama. Some Japanese physicists 223 00:10:23.080 --> 00:10:26.720 Watanabi and Oshikawa proved a theorem, effectively saying will Check 224 00:10:26.799 --> 00:10:30.600 is wrong. You can't have a time crystal and thermal equilibrium. 225 00:10:29.879 --> 00:10:33.080 So it can't happen in that ground state you described, not. 226 00:10:33.200 --> 00:10:36.720 In a simple static equilibrium system. It was a heavy blow. 227 00:10:37.039 --> 00:10:38.399 It looked like the idea was dead. 228 00:10:38.440 --> 00:10:39.320 So the idea died. 229 00:10:39.559 --> 00:10:43.559 No, it pivoted. Physicists are clever. They realized, Okay, maybe 230 00:10:43.559 --> 00:10:46.080 we can't have them in perfect equilibrium, but what if 231 00:10:46.080 --> 00:10:49.399 we have them in a driven system, a system that 232 00:10:49.399 --> 00:10:53.200 we poke periodically, but the system responds in a weird way. 233 00:10:53.279 --> 00:10:55.480 This is what led to the twenty sixteen experiments. 234 00:10:55.879 --> 00:10:59.879 Exactly, in twenty sixteen, two different groups, one led by 235 00:11:00.080 --> 00:11:03.799 Chris Monroe and Maryland and another by Mikhyle Luken at 236 00:11:03.799 --> 00:11:06.879 Harvard created the first discrete time crystals. 237 00:11:07.039 --> 00:11:07.960 And how did they do that? 238 00:11:08.039 --> 00:11:11.159 They took ions, trap them in electromagnetic field, and hit 239 00:11:11.200 --> 00:11:15.320 them with lasers in a pulse bang bang, bang, a 240 00:11:15.399 --> 00:11:16.080 regular rhythm. 241 00:11:16.159 --> 00:11:18.320 So they were adding energy. That sounds like the pendulum. 242 00:11:18.360 --> 00:11:21.080 Again, they were adding energy. But here's the magic trick. 243 00:11:21.320 --> 00:11:24.480 They hit the system with a laser every t seconds. 244 00:11:25.600 --> 00:11:28.159 But the system didn't repeat every two seconds. It didn't 245 00:11:28.240 --> 00:11:31.440 know it repeated every two t seconds or three t seconds. 246 00:11:32.000 --> 00:11:35.360 It broke the symmetry of the driver. It adopted its own, slower, 247 00:11:35.480 --> 00:11:36.519 more stable rhythm. 248 00:11:36.519 --> 00:11:37.879 Wait, I want to make sure I get this. It's 249 00:11:37.960 --> 00:11:40.320 like if I'm jumping rope and the rope comes around 250 00:11:40.320 --> 00:11:42.080 every second, but I only jump every two seconds. 251 00:11:42.159 --> 00:11:45.159 Yes, you have created a new period that is different 252 00:11:45.159 --> 00:11:47.480 from the driving force. You're not just a puppet of 253 00:11:47.519 --> 00:11:49.399 the rope. You've established your own. 254 00:11:49.200 --> 00:11:52.759 Pattern and it holds that pattern rigidly, incredibly rigidly. 255 00:11:53.159 --> 00:11:55.879 That was the proof that the material was creating its 256 00:11:55.919 --> 00:11:58.960 own timeline. It wasn't just mirroring the laser. It was 257 00:11:59.000 --> 00:12:02.399 doing its own thing, locking into a sub harmonic frequency. 258 00:12:02.480 --> 00:12:05.039 So ten years ago we proved they exist. We found 259 00:12:05.080 --> 00:12:06.159 the loophole. 260 00:12:05.879 --> 00:12:10.720 We did We realized, Okay, nature actually allows this weird behavior. Yeah, 261 00:12:10.720 --> 00:12:12.799 but for the last ten years the conversation has been 262 00:12:13.159 --> 00:12:15.960 that's a cool party trick physics, but what can we 263 00:12:16.000 --> 00:12:17.240 actually do with it? 264 00:12:17.240 --> 00:12:19.519 It's the classic solution in search of. 265 00:12:19.440 --> 00:12:22.639 A problem exactly. And that brings us to twenty twenty 266 00:12:22.679 --> 00:12:26.039 six because the study we are looking at today, the 267 00:12:26.120 --> 00:12:29.559 Viati paper, moves the goalposts from look at this weird 268 00:12:29.600 --> 00:12:31.639 thing to let's build a machine with this. 269 00:12:31.879 --> 00:12:33.559 And the machine they want to build is the most 270 00:12:33.600 --> 00:12:35.240 precise clock in the universe. 271 00:12:35.399 --> 00:12:38.519 That's the ambition. And to understand why that is such 272 00:12:38.519 --> 00:12:41.039 a big deal, we have to talk about the villain 273 00:12:41.080 --> 00:12:44.639 of our story. The villain yes, the current status quill 274 00:12:44.720 --> 00:12:45.879 the atomic clock. 275 00:12:45.759 --> 00:12:48.960 Which begs the question what is wrong with the clocks 276 00:12:49.000 --> 00:12:52.360 we have now? I mean, my phone seems pretty accurate. 277 00:12:52.639 --> 00:12:55.000 The GPS on my car gets me to the grocery store. 278 00:12:55.519 --> 00:13:00.600 We have caesium clocks, strontium clocks. Why are scientists obsessed 279 00:13:00.639 --> 00:13:03.080 with making better clocks? Are we just splitting hairs at 280 00:13:03.080 --> 00:13:04.000 this point. 281 00:13:03.879 --> 00:13:06.320 It might seem like that, but for science and technology 282 00:13:06.320 --> 00:13:10.000 we are absolutely not splitting hairs. To answer that, we 283 00:13:10.080 --> 00:13:12.279 have to look at how we define time right now 284 00:13:13.000 --> 00:13:16.559 at the highest level, the level that governs GPS, the Internet, 285 00:13:16.600 --> 00:13:21.519 banking systems, and deep space navigation. We rely on optical atomic. 286 00:13:21.120 --> 00:13:22.879 Clocks, and these are the best we have. 287 00:13:23.000 --> 00:13:26.440 They are marvels of engineering. The latest strontium lattice clock, 288 00:13:26.480 --> 00:13:29.159 for instance, wouldn't lose or gain a second in about 289 00:13:29.240 --> 00:13:30.240 fifteen billion. 290 00:13:30.039 --> 00:13:32.480 Years, longer than the age of the universe exactly. 291 00:13:32.720 --> 00:13:36.159 So they are incredible, but they have some serious achilles heels. 292 00:13:36.480 --> 00:13:39.519 I've heard the term, but what is actually happening inside 293 00:13:39.519 --> 00:13:42.480 an atomic clock? It's not gears and springs, obviously. 294 00:13:42.399 --> 00:13:46.559 No, it's about energy levels and light. So let's look 295 00:13:46.600 --> 00:13:49.679 at a modern optical lattice clock. Imagine you have a 296 00:13:49.759 --> 00:13:54.759 vacuum chamber inside you trap thousands of atoms, usually strontium 297 00:13:54.840 --> 00:13:57.399 or yuterbium, using interfering laser beams. 298 00:13:57.440 --> 00:13:58.360 You're holding them with light. 299 00:13:58.559 --> 00:14:01.080 Holding them with light, were eating a shape like an 300 00:14:01.080 --> 00:14:04.000 egg crate. We call it an optical lattice. Each egg 301 00:14:04.399 --> 00:14:07.399 in the crate holds one atom, keeping them from bumping 302 00:14:07.399 --> 00:14:09.000 into each other and messing up the measurement. 303 00:14:09.039 --> 00:14:10.639 Okay, I've got my atoms. They are stuck in the 304 00:14:10.639 --> 00:14:11.159 egg crate. 305 00:14:11.639 --> 00:14:14.879 You cool them down, atom mean really cool. We use 306 00:14:14.960 --> 00:14:18.000 lasers to slow them down, a process called Doppler cooling 307 00:14:18.279 --> 00:14:22.000 to get them to microkelvin's barely above absolute zero. They're 308 00:14:22.080 --> 00:14:23.240 almost perfectly still. 309 00:14:23.679 --> 00:14:25.639 Okay, so we have frozen trapped atoms. 310 00:14:25.679 --> 00:14:28.440 Now what then you bring in the clock laser. This 311 00:14:28.480 --> 00:14:30.879 is a separate ultra stable laser tune too, a very 312 00:14:30.919 --> 00:14:33.279 specific frequency of light. You shine it on the atoms. 313 00:14:33.639 --> 00:14:36.879 If the frequency is exactly right, I mean exactly, it 314 00:14:36.919 --> 00:14:39.039 will excite the electrons in the atom to jump to 315 00:14:39.080 --> 00:14:40.200 a higher energy orbit. 316 00:14:40.320 --> 00:14:42.840 The quantum leap we were talking about the quantum leap. 317 00:14:43.240 --> 00:14:45.639 It's a very narrow resonance think of it like a 318 00:14:45.720 --> 00:14:48.919 key fitting a lock. Only one frequency will work. When 319 00:14:48.919 --> 00:14:51.279 you find that exact frequency that makes the jump happen, 320 00:14:51.440 --> 00:14:54.279 you know, okay, this frequency is our standard. You count 321 00:14:54.320 --> 00:14:56.960 the oscillations of that light. That is your tick. 322 00:14:57.279 --> 00:14:59.879 So the atom is the reference, it's the tuning for 323 00:15:00.440 --> 00:15:02.639 the laser is the bow playing the violin. 324 00:15:03.200 --> 00:15:06.120 That is a perfect analogy. The atom is the tuning fork, 325 00:15:06.159 --> 00:15:08.720 which is perfect and unchanging. The laser is the bow. 326 00:15:09.480 --> 00:15:11.559 But here is the problem with current technology. 327 00:15:11.679 --> 00:15:12.480 What's the problem. 328 00:15:12.639 --> 00:15:14.919 The ticked doesn't actually come from the atom. It comes 329 00:15:14.919 --> 00:15:17.759 from the laser. The laser is the thing generating the wave. 330 00:15:18.200 --> 00:15:19.960 We just use the atom to check if the laser 331 00:15:20.000 --> 00:15:20.399 is correct. 332 00:15:20.440 --> 00:15:22.639 So we're constantly asking the atom is this right? Is 333 00:15:22.679 --> 00:15:24.000 this right? Am I still on key? 334 00:15:24.279 --> 00:15:26.759 Yes, we lock the laser to the atom in a 335 00:15:26.759 --> 00:15:30.879 feedback loop. But lasers. Lasers are man made. They are imperfect. 336 00:15:31.080 --> 00:15:33.559 They have what we call phase noise. The mirrors in 337 00:15:33.600 --> 00:15:37.799 the laser cavity vibrate due to heat the electronics. 338 00:15:37.200 --> 00:15:38.679 Fluctuations, so the bow is shaky. 339 00:15:39.000 --> 00:15:41.919 The bow is shaky, and because the bow is shaky, 340 00:15:42.159 --> 00:15:45.120 we have to constantly correct it. This process creates a 341 00:15:45.159 --> 00:15:49.679 limit on stability. We are fighting a constant war against decoherence. 342 00:15:50.000 --> 00:15:53.759 What's that It's the laser noise scrambling the quantum information 343 00:15:53.840 --> 00:15:57.440 in the atoms. It's the external world messing up your 344 00:15:57.480 --> 00:15:58.559 perfect quantum state. 345 00:15:58.799 --> 00:16:01.639 And that limits how precise the clock can be. 346 00:16:01.720 --> 00:16:05.240 It limits the coherence time. Ideally, you want to interrogate 347 00:16:05.240 --> 00:16:07.639 the atom for a long time to get a precise measurement, 348 00:16:08.120 --> 00:16:10.279 but because the laser is noisy, you can't. You have 349 00:16:10.360 --> 00:16:13.240 to take short snapshots. It limits the ultimate precision. 350 00:16:13.679 --> 00:16:18.039 So the source material highlights these drawbacks. What are they specifically? 351 00:16:18.159 --> 00:16:22.360 Yes, it lists three big costs. First, complexity, these systems 352 00:16:22.360 --> 00:16:26.000 are absolute beasts. To manage you need vacuum chambers, multiple 353 00:16:26.080 --> 00:16:29.879 lasers for cooling, repumping, trapping, and the clock laser itself. 354 00:16:29.919 --> 00:16:31.440 It's a room full of equipment, so. 355 00:16:31.440 --> 00:16:33.720 You can't exactly wear one on your wrist or even 356 00:16:33.799 --> 00:16:35.480 put one in a small satellite easily. 357 00:16:35.600 --> 00:16:39.120 Definitely not. Second, they are fragile. They are incredibly sensitive 358 00:16:39.159 --> 00:16:42.000 to vibrations and temperature changes. If you shake them, the 359 00:16:42.039 --> 00:16:44.960 lattice breaks, the atoms fall out. And the third energy, 360 00:16:45.720 --> 00:16:48.200 and this is the big one for our discussion regarding 361 00:16:48.240 --> 00:16:52.639 the time crystal. To run an optical atomic clock, you 362 00:16:52.679 --> 00:16:56.159 are constantly blasting it with energy. You are driving the system. 363 00:16:56.559 --> 00:16:59.039 You are forcing the electrons up, they fall down, you 364 00:16:59.120 --> 00:16:59.600 push them. 365 00:16:59.519 --> 00:17:01.519 Up again, have to keep pushing the swing. If you 366 00:17:01.519 --> 00:17:03.240 stop pushing, the swinging stops. 367 00:17:03.399 --> 00:17:06.920 Exactly, you're constantly pumping energy into the system to force 368 00:17:06.960 --> 00:17:10.240 it to oscillate. This is an active system, and in 369 00:17:10.319 --> 00:17:13.880 quantum mechanics, active systems are prone to noise. The very 370 00:17:13.920 --> 00:17:15.920 act of pushing the atom disturbs it. 371 00:17:16.000 --> 00:17:18.599 So we have these amazing clocks, but they are energy hogs, 372 00:17:18.640 --> 00:17:21.079 They are fragile, and they only work because we are 373 00:17:21.119 --> 00:17:23.839 constantly bullying the atoms into keeping time. 374 00:17:24.119 --> 00:17:26.000 That's a very colorful way to put it, but yes, 375 00:17:26.400 --> 00:17:29.559 we are forcing order onto a chaotic system, and that 376 00:17:29.599 --> 00:17:32.319 brings us to Ludmilaviatti and her team. 377 00:17:32.319 --> 00:17:33.319 Enter the time crystal. 378 00:17:33.519 --> 00:17:34.480 Enter the time crystal. 379 00:17:34.680 --> 00:17:37.640 So the proposal from this news study published just this 380 00:17:37.720 --> 00:17:40.519 month February twenty twenty six is to throw out the 381 00:17:40.559 --> 00:17:42.640 idea of the bullied atom and replace it with a 382 00:17:42.720 --> 00:17:44.039 quantum time crystal clock. 383 00:17:44.359 --> 00:17:46.960 Right, And the core difference. The thing that makes this 384 00:17:47.079 --> 00:17:51.640 revolutionary is that a time crystal does not require that 385 00:17:51.839 --> 00:17:58.079 continuous energy intensive external excitation to sustain its oscillation in 386 00:17:58.119 --> 00:17:58.720 the same way. 387 00:17:58.839 --> 00:18:00.880 This goes back to what we said earlier. The rhythm 388 00:18:00.920 --> 00:18:02.880 is internal. It's not coming from a laser. 389 00:18:03.200 --> 00:18:07.160 Yes, the repeating pattern, the tick of the clock emerges 390 00:18:07.200 --> 00:18:10.079 from the intrinsic interactions within the system itself. 391 00:18:10.279 --> 00:18:14.400 I need an analogy because intrinsic interactions sounds like corporate 392 00:18:14.440 --> 00:18:16.400 speech for a team building exercise. 393 00:18:16.480 --> 00:18:19.599 Fair enough, Okay, think about the atomic clock the old way. 394 00:18:19.680 --> 00:18:22.240 Like a class of students trying to clap in unit 395 00:18:22.319 --> 00:18:25.079 in Okay, to get them to clap together, the teacher 396 00:18:25.160 --> 00:18:28.720 the laser has to stand at the front and conduct them. Clap, clap, clap. 397 00:18:29.240 --> 00:18:31.799 If the teacher stops, the students stop or fall out 398 00:18:31.799 --> 00:18:32.200 a rhythm. 399 00:18:32.200 --> 00:18:34.680 Okay, that's the external drive. Makes sense. 400 00:18:34.799 --> 00:18:37.480 Now, imagine a time crystal. The teacher leaves the room, 401 00:18:37.720 --> 00:18:42.000