1 00:00:07,280 --> 00:00:10,280 Speaker 1: Hey, Daniel, do you somebody's feel when you're bored time 2 00:00:10,800 --> 00:00:13,880 Speaker 1: slows down? That never happens to me when I'm talking 3 00:00:13,880 --> 00:00:16,599 Speaker 1: to you, or Hey, every conversation with you is riveting, 4 00:00:16,600 --> 00:00:20,680 Speaker 1: It goes back super fast. That's right. Time just flies by, 5 00:00:21,400 --> 00:00:22,680 Speaker 1: you know, and call you up, and then all of 6 00:00:22,720 --> 00:00:24,680 Speaker 1: a sudden it's hours later. Do you know what I mean? Like, 7 00:00:24,720 --> 00:00:29,200 Speaker 1: it's the idea that maybe time is relative in our heads. No, 8 00:00:29,360 --> 00:00:31,680 Speaker 1: I think that's true. When you're waiting for something, time 9 00:00:31,760 --> 00:00:34,600 Speaker 1: feels like it goes really slow. When you're listening to 10 00:00:34,640 --> 00:00:37,920 Speaker 1: your favorite podcast hosts, it just whizzes right by. We're 11 00:00:38,000 --> 00:00:41,440 Speaker 1: pretty bad at measuring time as a species, are we really? 12 00:00:41,440 --> 00:00:44,640 Speaker 1: Like our brains are not good at estimating time? Oh yeah, 13 00:00:44,680 --> 00:00:46,479 Speaker 1: they do all these experiments where they ask people to 14 00:00:46,560 --> 00:00:49,839 Speaker 1: estimate how long something has been, and they always over underestimated. 15 00:00:50,960 --> 00:00:54,680 Speaker 1: So psychologically time can be relative. That's proven. But what 16 00:00:54,800 --> 00:00:58,600 Speaker 1: about physics can that actually happen? Yeah? It turns out 17 00:00:58,640 --> 00:01:02,440 Speaker 1: that physics also doesn't provide a bedrock layer of truth 18 00:01:02,920 --> 00:01:07,560 Speaker 1: that time can slow down. Huh, So there's no universal clock, like, 19 00:01:07,640 --> 00:01:12,720 Speaker 1: there's no impartial, godlike measure of time. That's right. So 20 00:01:12,880 --> 00:01:14,600 Speaker 1: if next time you're late for a meeting, you can 21 00:01:14,600 --> 00:01:16,880 Speaker 1: just say, hey, I got my own clock and my 22 00:01:16,920 --> 00:01:20,840 Speaker 1: observer says I was on time. Physics gives you an 23 00:01:20,880 --> 00:01:39,880 Speaker 1: excuse to be late for your meeting. And I'm Daniel. 24 00:01:40,120 --> 00:01:43,400 Speaker 1: Welcome to our podcast Daniel and Jorgey explain the universe, 25 00:01:43,520 --> 00:01:45,720 Speaker 1: in which we take plenty of time to explain to 26 00:01:45,760 --> 00:01:48,920 Speaker 1: you how time works in the universe. Hey, yeah, we're 27 00:01:48,960 --> 00:01:51,480 Speaker 1: here to help you. Whatever it is you're doing, communing 28 00:01:51,480 --> 00:01:54,200 Speaker 1: to work on a subway, going out for a jog. 29 00:01:54,480 --> 00:01:56,440 Speaker 1: We're here to help the time move a little bit 30 00:01:56,440 --> 00:01:58,720 Speaker 1: faster for you. That's right. We're here to kill some 31 00:01:58,840 --> 00:02:01,080 Speaker 1: time for you, and out's time to get on with it. 32 00:02:01,200 --> 00:02:11,000 Speaker 1: So today's topic is why do clocks run slower when 33 00:02:11,040 --> 00:02:14,359 Speaker 1: they are moving fast? That's right. This is a really 34 00:02:14,440 --> 00:02:17,720 Speaker 1: popular thing for people to get confused about in relativity. 35 00:02:18,560 --> 00:02:22,760 Speaker 1: It's technically called time dilation, the fact that clocks that 36 00:02:22,840 --> 00:02:26,440 Speaker 1: move fast run slow, and it's a topic that confuses 37 00:02:26,480 --> 00:02:30,040 Speaker 1: people from here to infinity. Yeah, it's the idea that 38 00:02:30,080 --> 00:02:32,639 Speaker 1: if you're going really fast, maybe it close up the 39 00:02:32,680 --> 00:02:36,440 Speaker 1: speed of light, then time slows down for you. That's right. 40 00:02:36,760 --> 00:02:38,800 Speaker 1: And the thing we want to understand today is not 41 00:02:38,880 --> 00:02:41,640 Speaker 1: just does it happen, but why does it happen? What 42 00:02:41,760 --> 00:02:43,959 Speaker 1: is it about the universe that makes that the way 43 00:02:43,960 --> 00:02:47,040 Speaker 1: it really works? And the thing that I love about 44 00:02:47,080 --> 00:02:49,440 Speaker 1: this is that it's one of the best examples of 45 00:02:49,440 --> 00:02:52,720 Speaker 1: how the universe doesn't work the way you think it does, 46 00:02:52,919 --> 00:02:55,919 Speaker 1: that it doesn't make sense to our sort of intuitive 47 00:02:56,000 --> 00:02:59,120 Speaker 1: understanding of the way the world should work, right, especially 48 00:02:59,200 --> 00:03:02,040 Speaker 1: at these extreme conditions. Right, that's right, because we're not 49 00:03:02,120 --> 00:03:05,280 Speaker 1: used to those extreme conditions. So we've like operated in 50 00:03:05,480 --> 00:03:07,280 Speaker 1: you know, on the surface of the Earth, which is 51 00:03:07,280 --> 00:03:10,640 Speaker 1: pretty slow speeds for thousands and thousands of years. We 52 00:03:10,720 --> 00:03:13,240 Speaker 1: build up these intuitive models for how we think the 53 00:03:13,360 --> 00:03:17,320 Speaker 1: universe behaves right, what the rules are, And one of 54 00:03:17,360 --> 00:03:20,160 Speaker 1: those rules is that we think that there is a 55 00:03:20,160 --> 00:03:22,600 Speaker 1: absolute history, right, We think that there is a reality 56 00:03:22,639 --> 00:03:25,919 Speaker 1: out there and that something actually happens and in the end, 57 00:03:26,000 --> 00:03:29,680 Speaker 1: everybody should agree if they're honest observers about what happened. 58 00:03:29,960 --> 00:03:33,320 Speaker 1: It turns out that's just not true. And hopefully this 59 00:03:33,440 --> 00:03:35,360 Speaker 1: is kind of a topic that a lot of people 60 00:03:35,520 --> 00:03:37,760 Speaker 1: have hopefully I think maybe have heard about. It's sort 61 00:03:37,760 --> 00:03:40,520 Speaker 1: of permeated out into popular culture a little bit, right, like, 62 00:03:40,560 --> 00:03:43,720 Speaker 1: it's the basis of the movie Interstellar. I knew you 63 00:03:43,760 --> 00:03:48,800 Speaker 1: were going to talk about Interstellar Interstellar reference, but it's 64 00:03:48,800 --> 00:03:51,480 Speaker 1: it's a big example of it in pop culture, right, 65 00:03:51,520 --> 00:03:54,880 Speaker 1: Like I think, really Interstellar was a pretty big movie 66 00:03:55,040 --> 00:03:58,080 Speaker 1: regardless of what your physicists thinks of it, and my 67 00:03:58,200 --> 00:03:59,920 Speaker 1: year and my year physicist is that how used to 68 00:04:00,320 --> 00:04:03,480 Speaker 1: refer to me? No, Interstellar actually did a pretty good 69 00:04:03,560 --> 00:04:06,520 Speaker 1: job of modeling the relativity portion. My issues with the 70 00:04:06,520 --> 00:04:08,960 Speaker 1: Interstellar are more about the time travel and going inside 71 00:04:08,960 --> 00:04:11,360 Speaker 1: a black hole. But from the point of view of relativity, 72 00:04:11,400 --> 00:04:12,560 Speaker 1: that made a lot of sense. I mean, I thought 73 00:04:12,560 --> 00:04:14,920 Speaker 1: it was good that they actually built into the plot 74 00:04:15,040 --> 00:04:17,680 Speaker 1: what would happen to various people's clocks. And that's the 75 00:04:17,760 --> 00:04:21,280 Speaker 1: key thing, is that relativity is all about comparing clocks. 76 00:04:21,279 --> 00:04:23,479 Speaker 1: How fast is my clock going to your compared to 77 00:04:23,520 --> 00:04:26,120 Speaker 1: your clock? So we're going to assume that you have 78 00:04:26,279 --> 00:04:28,599 Speaker 1: heard of this concept that if you are in a 79 00:04:28,600 --> 00:04:32,200 Speaker 1: spaceship going really fast and time will slow down for you. 80 00:04:32,560 --> 00:04:36,200 Speaker 1: But we were wondering how many people out there know why? 81 00:04:36,560 --> 00:04:39,560 Speaker 1: So as usual, I tortured the undergraduates of you see 82 00:04:39,560 --> 00:04:42,880 Speaker 1: Irvine by walking around and asking them random questions without 83 00:04:42,920 --> 00:04:45,920 Speaker 1: any preparation. And remember, for those of you who think 84 00:04:45,960 --> 00:04:48,760 Speaker 1: that these answers are silly, these are hard questions to 85 00:04:48,800 --> 00:04:50,680 Speaker 1: answer on the top of your head, so give them 86 00:04:50,720 --> 00:04:55,200 Speaker 1: some slack. It's tortured. This called the physics boarding, enhanced 87 00:04:55,240 --> 00:05:00,839 Speaker 1: physics exactly, physics boarding, you know, exactly. I'm gonna cover 88 00:05:00,920 --> 00:05:05,760 Speaker 1: your face with a towel and poor physics on your face. Um. Eventually, 89 00:05:05,839 --> 00:05:07,680 Speaker 1: I think the undergrads are gonna recognize me, and they're 90 00:05:07,680 --> 00:05:09,320 Speaker 1: gonna be like, don't let that guy talk to you. 91 00:05:09,440 --> 00:05:11,960 Speaker 1: He'll embarrass you. Run away. We're not trying to embarrass 92 00:05:12,000 --> 00:05:14,560 Speaker 1: these people. No, it's great. I think I would be 93 00:05:14,600 --> 00:05:17,280 Speaker 1: totally flabbergasted if you asked me these questions out of 94 00:05:17,320 --> 00:05:19,360 Speaker 1: the street. All right, I'll plan the ambush you one day. 95 00:05:19,640 --> 00:05:22,080 Speaker 1: So before you listen to these answers, think for yourself. 96 00:05:22,440 --> 00:05:24,880 Speaker 1: Do you know what time dilation is? Can you explain 97 00:05:25,320 --> 00:05:29,440 Speaker 1: why moving clocks run more slowly? Here's what people had 98 00:05:29,440 --> 00:05:33,200 Speaker 1: to say. Have you heard of time dilation? Do you 99 00:05:33,200 --> 00:05:37,320 Speaker 1: know that clocks that move really fast go slower? This 100 00:05:37,440 --> 00:05:40,920 Speaker 1: is trying your information to me. Yes, do you know 101 00:05:40,960 --> 00:05:44,240 Speaker 1: why that is? No? I don't know the real reason. 102 00:05:44,880 --> 00:05:51,920 Speaker 1: I'm sorry, No, no, there is no time, thanks very much. 103 00:05:52,040 --> 00:05:53,719 Speaker 1: All right, So maybe I was a little wrong. Not 104 00:05:53,760 --> 00:05:56,280 Speaker 1: a lot of people have heard about this concept. That's right, 105 00:05:56,279 --> 00:05:57,839 Speaker 1: and there are even people out there that deny the 106 00:05:57,880 --> 00:06:03,120 Speaker 1: time exists. Right, there is no time, there is no 107 00:06:03,240 --> 00:06:05,760 Speaker 1: concept of time, or that there was not enough time 108 00:06:05,800 --> 00:06:07,520 Speaker 1: to explain it to you. You know, I was so 109 00:06:07,560 --> 00:06:10,560 Speaker 1: flabbergasted by the response. I couldn't even formulate a follow 110 00:06:10,640 --> 00:06:13,520 Speaker 1: up question. I was like still processing, like, what does 111 00:06:13,560 --> 00:06:16,440 Speaker 1: that even mean? Wow? Did he did he just dropped 112 00:06:16,520 --> 00:06:19,960 Speaker 1: or she dropped the bike? There is no time? Great phase. 113 00:06:20,920 --> 00:06:22,960 Speaker 1: She said it with a lot of finality. Yeah, So 114 00:06:23,080 --> 00:06:26,080 Speaker 1: there wasn't a whole lot of opening there for interrogation 115 00:06:26,240 --> 00:06:28,520 Speaker 1: or follow up questions. It was like, this is a 116 00:06:28,560 --> 00:06:31,120 Speaker 1: clearly known fact, there is no time. Well, I mean 117 00:06:31,200 --> 00:06:32,719 Speaker 1: she was just going to rush and she's like, I 118 00:06:32,760 --> 00:06:35,040 Speaker 1: have no time for this. No. I think it was 119 00:06:35,080 --> 00:06:37,800 Speaker 1: definitely more of the time and time is an illusion. 120 00:06:38,120 --> 00:06:40,400 Speaker 1: So an answer, Yeah, I've heard of that time is 121 00:06:40,400 --> 00:06:42,520 Speaker 1: an illusion. Yeah, Well, I think we have to do 122 00:06:42,560 --> 00:06:44,919 Speaker 1: a whole other podcast episode about what is time and 123 00:06:44,960 --> 00:06:46,440 Speaker 1: how does it work? And why does it only go 124 00:06:46,520 --> 00:06:48,560 Speaker 1: forward and all that kind of stuff. But this is 125 00:06:48,600 --> 00:06:51,040 Speaker 1: kind of related. This topic is related to that idea 126 00:06:51,120 --> 00:06:54,840 Speaker 1: that time is not what we think it is. That's right. 127 00:06:55,040 --> 00:06:57,000 Speaker 1: We've met a lot of progress in the last hundred 128 00:06:57,040 --> 00:06:59,920 Speaker 1: years in understanding time, and we've connected it to space. 129 00:07:00,440 --> 00:07:02,919 Speaker 1: You've probably heard the concept of space time, right. We 130 00:07:02,920 --> 00:07:06,159 Speaker 1: have three dimensions at least of space and one dimension 131 00:07:06,200 --> 00:07:08,800 Speaker 1: of time, and Einstein's relativity tied them together and showed 132 00:07:08,880 --> 00:07:11,520 Speaker 1: us how time and space are connected. But that doesn't 133 00:07:11,560 --> 00:07:14,040 Speaker 1: mean that time can be simply understood as a fourth 134 00:07:14,040 --> 00:07:16,920 Speaker 1: dimension of space. It's much more complicated. It's different from 135 00:07:16,920 --> 00:07:22,480 Speaker 1: the other dimensions of space. Yeah, they're all tied together, time, speed, space, 136 00:07:22,880 --> 00:07:26,240 Speaker 1: It's all one big molasses of a universe. It's all 137 00:07:26,280 --> 00:07:28,760 Speaker 1: one big tangle. The amazing thing is that it actually 138 00:07:28,840 --> 00:07:31,440 Speaker 1: all does work. You know. We have this new version 139 00:07:31,560 --> 00:07:33,840 Speaker 1: of our understanding of the universe, not that new anymore 140 00:07:33,880 --> 00:07:37,080 Speaker 1: as a hundred years old, but this revised version of 141 00:07:37,120 --> 00:07:40,160 Speaker 1: our understanding the universe, and it actually hangs together. I mean, 142 00:07:40,160 --> 00:07:42,800 Speaker 1: the answers that gives you don't make any sense to 143 00:07:42,840 --> 00:07:44,880 Speaker 1: your intuition, Like they fly in the face of what 144 00:07:44,960 --> 00:07:47,920 Speaker 1: you think should happen. They require you to like throw 145 00:07:47,960 --> 00:07:50,760 Speaker 1: out the way you think the universe works, but they 146 00:07:50,760 --> 00:07:54,640 Speaker 1: actually do hang together mathematically and they are correct. Like 147 00:07:54,720 --> 00:07:57,520 Speaker 1: every time we make a ridiculous prediction from relativity and 148 00:07:57,520 --> 00:07:59,840 Speaker 1: God and check it, the universe is like, yep, that 149 00:08:00,120 --> 00:08:03,920 Speaker 1: ridiculous thing actually happens. Well, let's bring it down for people. 150 00:08:04,120 --> 00:08:07,920 Speaker 1: So what does it mean for clocks to run slower 151 00:08:07,960 --> 00:08:11,440 Speaker 1: when they move fast? So that's that's what we're exploring, 152 00:08:11,640 --> 00:08:14,280 Speaker 1: and that's what we're trying to explain, is why when 153 00:08:14,280 --> 00:08:17,360 Speaker 1: you're moving really fast, your clock is going to actually 154 00:08:17,520 --> 00:08:20,520 Speaker 1: slow down. Right, And so let's be very careful and 155 00:08:20,520 --> 00:08:22,480 Speaker 1: how we say this, because a lot of people get confused. 156 00:08:22,520 --> 00:08:25,200 Speaker 1: People think that if you are moving fast, that your 157 00:08:25,240 --> 00:08:27,920 Speaker 1: clock slows down. That like, if you're looking at your 158 00:08:27,920 --> 00:08:31,320 Speaker 1: watch and running that you can see the seconds tick slower. 159 00:08:31,440 --> 00:08:34,440 Speaker 1: That's not true. If you're holding a clock and the 160 00:08:34,480 --> 00:08:37,040 Speaker 1: clock is not moving relative to you, you'll always see 161 00:08:37,040 --> 00:08:39,480 Speaker 1: it moving at one second per second. Okay, no matter 162 00:08:39,520 --> 00:08:42,520 Speaker 1: how fast you're going relative to anything else, your clock 163 00:08:42,800 --> 00:08:44,959 Speaker 1: always runs the same way. It's not like I get 164 00:08:44,960 --> 00:08:49,839 Speaker 1: on a spaceship hit the warp speed and then that's 165 00:08:49,880 --> 00:08:52,840 Speaker 1: not what I experienced. That's right. You never notice your 166 00:08:52,880 --> 00:08:55,960 Speaker 1: own time changing, right, you experienced time at one second 167 00:08:55,960 --> 00:08:59,800 Speaker 1: per second, no matter what. Okay, the thing that does 168 00:09:00,040 --> 00:09:03,920 Speaker 1: happen is that clock's moving relative to you. Right. So, 169 00:09:03,960 --> 00:09:06,240 Speaker 1: if I'm standing still and Horge has a clock and 170 00:09:06,320 --> 00:09:08,640 Speaker 1: he runs because he's a pretty zippy guy, if he 171 00:09:08,760 --> 00:09:10,920 Speaker 1: runs a half speed of light because I'm running late, 172 00:09:11,040 --> 00:09:16,199 Speaker 1: probably if I notice that he's moving really fast, then 173 00:09:16,280 --> 00:09:19,360 Speaker 1: I will see his clock running more slowly. Right. So, 174 00:09:19,400 --> 00:09:21,760 Speaker 1: now from his point of view, he will see his 175 00:09:21,800 --> 00:09:24,360 Speaker 1: clock running normally, but I will see his clock running 176 00:09:24,400 --> 00:09:26,760 Speaker 1: more slowly. If I'm zooming past you and you just 177 00:09:26,920 --> 00:09:30,160 Speaker 1: look at my clock as I'm zooing by, it's not 178 00:09:30,200 --> 00:09:32,600 Speaker 1: going to be running at the same speed as your clock, 179 00:09:32,800 --> 00:09:34,600 Speaker 1: that's right. If I'm watching you as you go by, 180 00:09:34,640 --> 00:09:37,920 Speaker 1: and I'm watching your clock's hands tick forward, right, then 181 00:09:37,960 --> 00:09:40,960 Speaker 1: they don't agree with mine. Yours mark the seconds more 182 00:09:41,040 --> 00:09:44,360 Speaker 1: slowly than my clock does. And that's the key thing 183 00:09:44,679 --> 00:09:48,560 Speaker 1: is that the observation of time depends on your relative 184 00:09:48,640 --> 00:09:52,000 Speaker 1: velocity to the clock. So it's not that it actually 185 00:09:52,040 --> 00:09:55,760 Speaker 1: slowed down for me at least, it just you saw 186 00:09:55,760 --> 00:09:58,040 Speaker 1: it run slower. Right. I love how you try to 187 00:09:58,080 --> 00:10:00,840 Speaker 1: use the word actually right because you're in your imagining, 188 00:10:01,080 --> 00:10:04,240 Speaker 1: there's some true version of the effect of the effect, right, 189 00:10:04,440 --> 00:10:07,520 Speaker 1: I'm just this is an illusion or it looks this way, 190 00:10:07,559 --> 00:10:10,240 Speaker 1: but it's not actually happening. The problem is there is 191 00:10:10,320 --> 00:10:14,480 Speaker 1: no what actually happened. Okay, I observe one thing, you 192 00:10:14,559 --> 00:10:18,040 Speaker 1: observe something else. We can both be right even if 193 00:10:18,080 --> 00:10:22,600 Speaker 1: those accounts disagree. WHOA Okay, So then I'm running past 194 00:10:22,679 --> 00:10:25,520 Speaker 1: you really fast with a clock and you see it 195 00:10:25,600 --> 00:10:28,200 Speaker 1: run slower than I do, or it's running slower than 196 00:10:28,240 --> 00:10:30,679 Speaker 1: your clock. Then what happens if I stopped, like if 197 00:10:30,679 --> 00:10:33,000 Speaker 1: I stopped a few paces after you, Does that mean 198 00:10:33,000 --> 00:10:35,200 Speaker 1: our clocks are going to be out of sync? Yes, 199 00:10:35,240 --> 00:10:38,160 Speaker 1: our clocks will definitely be out of sync, exactly, And 200 00:10:38,360 --> 00:10:40,960 Speaker 1: there's a lot of interesting effects there. Right. So I'm 201 00:10:41,000 --> 00:10:43,120 Speaker 1: a I'm standing still from my point of view, right, 202 00:10:43,360 --> 00:10:45,959 Speaker 1: and you're running past me. I see your clock moving 203 00:10:45,960 --> 00:10:48,960 Speaker 1: more slowly. I see my clock running normally. Right, what 204 00:10:49,040 --> 00:10:52,920 Speaker 1: do you see? Well, you see your clock running normally, right, 205 00:10:52,960 --> 00:10:55,640 Speaker 1: because everybody sees their own clock running normally. But you 206 00:10:55,720 --> 00:10:59,720 Speaker 1: also see my clock running slowly because even though you're 207 00:10:59,720 --> 00:11:03,040 Speaker 1: doing doing the running, I'm moving relative to you and 208 00:11:03,080 --> 00:11:05,320 Speaker 1: your clock. So then what happens if I stopped, Because 209 00:11:05,320 --> 00:11:08,320 Speaker 1: I'm gonna think time moved normally, But when when I 210 00:11:08,320 --> 00:11:10,840 Speaker 1: compare my clock to your clock, your clock will have 211 00:11:10,880 --> 00:11:14,800 Speaker 1: skipped ahead because right or no, we'll have skip back. 212 00:11:15,280 --> 00:11:19,079 Speaker 1: This is really tricky, okay, and we should probably avoid 213 00:11:19,120 --> 00:11:21,400 Speaker 1: this topic. Well maybe we won't. Let's dig into it. 214 00:11:26,440 --> 00:11:30,160 Speaker 1: This is called the twin paradox, right, This is people say, well, 215 00:11:30,200 --> 00:11:33,199 Speaker 1: how do you reconcile this? Right? So the classic framing 216 00:11:33,240 --> 00:11:36,480 Speaker 1: of this is, say we're twins, right, and I stay 217 00:11:36,640 --> 00:11:39,319 Speaker 1: on We draw straws for Hugas to go to Alpha Centauri, 218 00:11:39,360 --> 00:11:41,280 Speaker 1: and you lose. So you have to go to Alpha 219 00:11:41,320 --> 00:11:43,520 Speaker 1: Centauri or you win. You have to go to Alpha Centauri. 220 00:11:44,000 --> 00:11:46,240 Speaker 1: I stand on Earth and you take a rocket shipped 221 00:11:46,240 --> 00:11:48,880 Speaker 1: Alpha Centauri, and I see your clock running more slowly. Okay, 222 00:11:48,920 --> 00:11:51,200 Speaker 1: well we sink First of all, we sink clocks like 223 00:11:51,240 --> 00:11:53,680 Speaker 1: before I take off. Yes, we're just going to sink clocks. 224 00:11:53,880 --> 00:11:57,400 Speaker 1: Time zero start go now, that's right, and I see 225 00:11:57,400 --> 00:12:00,720 Speaker 1: your clock running more slowly. Meanwhile, you have telescope. You're 226 00:12:00,720 --> 00:12:03,160 Speaker 1: looking at my clock. You see mine running more slowly. Right, 227 00:12:03,559 --> 00:12:07,760 Speaker 1: so we both see the other person as aging more slowly. Right. 228 00:12:07,800 --> 00:12:10,439 Speaker 1: So now after a hundred years, you see me as 229 00:12:10,480 --> 00:12:12,280 Speaker 1: only being ten years older, and I see you as 230 00:12:12,320 --> 00:12:14,840 Speaker 1: only being ten years older, right, right, So then I 231 00:12:14,960 --> 00:12:18,320 Speaker 1: come back and then what happened? Who's older? All right, 232 00:12:18,360 --> 00:12:21,400 Speaker 1: let's break this down really carefully because it is tricky. 233 00:12:21,440 --> 00:12:24,760 Speaker 1: So when the Earth twin is watching the ship twins clock, 234 00:12:25,200 --> 00:12:27,960 Speaker 1: he of course sees time moving more slowly on the ship, right, 235 00:12:28,000 --> 00:12:31,720 Speaker 1: that's relativity. The same way when the ship twin watches 236 00:12:31,760 --> 00:12:34,920 Speaker 1: the Earth twins clock, he also sees time moving more 237 00:12:34,960 --> 00:12:37,640 Speaker 1: slowly on Earth. So far everything is symmetric, right, and 238 00:12:37,679 --> 00:12:40,040 Speaker 1: that's why we like it. Because you could be in ship, 239 00:12:40,120 --> 00:12:41,880 Speaker 1: you could be in the Earth. That shouldn't really matter, 240 00:12:42,080 --> 00:12:44,960 Speaker 1: right now. If they just kept going this way, nothing 241 00:12:44,960 --> 00:12:48,000 Speaker 1: would change. Of course, they would have conflicting views of 242 00:12:48,080 --> 00:12:51,440 Speaker 1: whose clock is moving slower, right, But that's okay. In relativity, 243 00:12:51,679 --> 00:12:54,600 Speaker 1: you can have two people with conflicting but both correct 244 00:12:54,760 --> 00:12:57,679 Speaker 1: views of the same situation, right, Because there is no 245 00:12:57,960 --> 00:13:00,880 Speaker 1: ultimate truth, right, your answer is depend on your speed 246 00:13:00,960 --> 00:13:03,920 Speaker 1: and your location. So what happens to break the symmetry? 247 00:13:04,160 --> 00:13:07,240 Speaker 1: The symmetry is broken when the space twin turns around. 248 00:13:07,640 --> 00:13:10,960 Speaker 1: That's an acceleration, right, That changes everything. Well, only the 249 00:13:11,000 --> 00:13:14,840 Speaker 1: space twin does any acceleration, so that makes his case different, right, 250 00:13:15,280 --> 00:13:18,920 Speaker 1: And during that acceleration, the time on Earth seems to 251 00:13:19,040 --> 00:13:21,800 Speaker 1: zoom forward really fast from the point of view of 252 00:13:21,800 --> 00:13:24,320 Speaker 1: the space twin. So on the way back, yeah, he 253 00:13:24,400 --> 00:13:27,640 Speaker 1: sees Earth moving fast and Earth clock going slowly. But 254 00:13:27,760 --> 00:13:31,720 Speaker 1: during that acceleration Earth time has leapt forward really far, 255 00:13:32,080 --> 00:13:34,320 Speaker 1: so that when the space twin gets back to Earth, 256 00:13:34,640 --> 00:13:37,560 Speaker 1: he's younger than his twin on Earth. Right, And the 257 00:13:37,679 --> 00:13:40,200 Speaker 1: reason they're no longer symmetric is that only the space 258 00:13:40,240 --> 00:13:43,360 Speaker 1: twin has done any acceleration, so you shouldn't expect them 259 00:13:43,520 --> 00:13:46,080 Speaker 1: to be the same from each point of view. It's 260 00:13:46,120 --> 00:13:51,600 Speaker 1: the coming back that then lets me stay younger. Yeah, exactly. Okay, 261 00:13:51,679 --> 00:13:55,000 Speaker 1: let's let's dig into it even more. But let's take 262 00:13:55,040 --> 00:14:09,960 Speaker 1: a quick break, all right. So this idea that time 263 00:14:10,040 --> 00:14:13,760 Speaker 1: moves slower when you're going fast, it's what's cool is 264 00:14:13,800 --> 00:14:16,880 Speaker 1: that it's always happening, right. It doesn't just happen when 265 00:14:16,880 --> 00:14:18,720 Speaker 1: you're going at the speed of light or close to 266 00:14:18,720 --> 00:14:21,520 Speaker 1: the speed of light. It's it happens like on your 267 00:14:21,560 --> 00:14:24,800 Speaker 1: on a daily basis, That's right. It applies all the time. 268 00:14:24,840 --> 00:14:27,480 Speaker 1: It always applies to things that have velocity relative to you. 269 00:14:28,040 --> 00:14:31,320 Speaker 1: But it's a really tiny effect if you're not going 270 00:14:31,360 --> 00:14:35,600 Speaker 1: really really fast. So when you're driving sixty in the freeway, yeah, 271 00:14:35,760 --> 00:14:38,000 Speaker 1: your clock is running a little bit slower, but you'll 272 00:14:38,000 --> 00:14:41,000 Speaker 1: never notice it. Wow, but it's there. Like if we're 273 00:14:41,080 --> 00:14:45,320 Speaker 1: all feeling relativity and time dilation all the time everywhere, 274 00:14:45,520 --> 00:14:49,360 Speaker 1: there's no way to escape relativity. It is everywhere. It's 275 00:14:49,400 --> 00:14:54,440 Speaker 1: relatively everywhere. It's absolutely every Absolutely thing about relativity is 276 00:14:54,480 --> 00:14:58,120 Speaker 1: that it's everywhere. Okay, so it only happens when you 277 00:14:58,120 --> 00:15:01,400 Speaker 1: get it's only noticeable. You're saying, when you're going to 278 00:15:01,520 --> 00:15:03,720 Speaker 1: close the speed up. But I heard it happens to 279 00:15:04,080 --> 00:15:07,320 Speaker 1: astronauts here on Earth, like the Space Shuttle. The clocks 280 00:15:08,160 --> 00:15:10,320 Speaker 1: get out of sync with the clocks on Earth. That's right, 281 00:15:10,360 --> 00:15:12,200 Speaker 1: though it takes a lot of precision to measure it. 282 00:15:12,200 --> 00:15:15,720 Speaker 1: It's something like every six months or so they lose 283 00:15:15,880 --> 00:15:18,720 Speaker 1: like less than a hundredth of a second. So it's 284 00:15:18,720 --> 00:15:20,920 Speaker 1: something we can measure, and they have really precise clocks 285 00:15:20,960 --> 00:15:24,080 Speaker 1: precisely to measure this to verify these predictions, but it's 286 00:15:24,080 --> 00:15:28,160 Speaker 1: not something that people have really like qualitatively experienced. We 287 00:15:28,200 --> 00:15:30,800 Speaker 1: haven't had an astronaut come back, you know, deep into 288 00:15:30,800 --> 00:15:34,200 Speaker 1: the future and still feel young. And it goes really nonlinear, right, 289 00:15:34,240 --> 00:15:36,520 Speaker 1: as you get faster and faster, the effect gets stronger 290 00:15:36,520 --> 00:15:40,560 Speaker 1: and stronger. But they did do the twin experiment with astronauts, right, Like, 291 00:15:40,600 --> 00:15:43,360 Speaker 1: they sent to one twin into space for a whole year, 292 00:15:43,480 --> 00:15:46,560 Speaker 1: and then he came back and technically he was point 293 00:15:46,600 --> 00:15:49,240 Speaker 1: oh one seconds younger. That's right. I wonder if he 294 00:15:49,280 --> 00:15:51,360 Speaker 1: was the one who was originally born first or the 295 00:15:51,360 --> 00:15:53,560 Speaker 1: one who's ovisually born second, because it be interesting and 296 00:15:53,640 --> 00:15:55,360 Speaker 1: be like, well you used to be the older twin, 297 00:15:55,440 --> 00:15:58,880 Speaker 1: but now I'm the older twin. A should have stayed 298 00:15:58,920 --> 00:16:02,160 Speaker 1: up there for ten more years. Do you think growing 299 00:16:02,200 --> 00:16:04,320 Speaker 1: up twins still argue by that kind of stuff. Well, 300 00:16:04,360 --> 00:16:06,640 Speaker 1: I'm the older brother, so you have to listen to me. 301 00:16:06,920 --> 00:16:09,720 Speaker 1: What do you think they're both austers. They're probably trying 302 00:16:09,720 --> 00:16:12,160 Speaker 1: to one up each other. Well, yeah, I'm an engineer. 303 00:16:12,200 --> 00:16:14,840 Speaker 1: Oh yeah, I'm a pilot. Oh yeah, I'm a I'm 304 00:16:14,880 --> 00:16:19,320 Speaker 1: an auster. Not me too, yeah, probably it never ends, right, 305 00:16:19,400 --> 00:16:22,280 Speaker 1: but technically that's true. He went out into space, went 306 00:16:22,280 --> 00:16:25,160 Speaker 1: around the Earth for a whole year. When he came back. Technically, 307 00:16:25,520 --> 00:16:29,240 Speaker 1: time for him moved one hundred of a second slower. Yeah, 308 00:16:29,240 --> 00:16:31,160 Speaker 1: I wonder what he's gonna do with all that extra time, 309 00:16:31,240 --> 00:16:34,840 Speaker 1: you know, scratches nose or something. Right, it's gone, he 310 00:16:35,000 --> 00:16:37,840 Speaker 1: lost it. He used it up. Yeah, But as you 311 00:16:37,880 --> 00:16:40,320 Speaker 1: go faster and faster, the effect gets stronger and stronger, 312 00:16:40,920 --> 00:16:43,800 Speaker 1: and as you approached the speed of light, time gets 313 00:16:43,840 --> 00:16:46,400 Speaker 1: so slow that we can say that if you go 314 00:16:46,520 --> 00:16:50,440 Speaker 1: the speed of light, time would actually stop. So if 315 00:16:50,520 --> 00:16:52,920 Speaker 1: I'm zooming running past you at the speed of light, 316 00:16:53,280 --> 00:16:57,040 Speaker 1: you would see my clock totally frozen, exactly. Now, caveats 317 00:16:57,040 --> 00:17:00,480 Speaker 1: are important here. Nothing that has mass actually go the 318 00:17:00,480 --> 00:17:03,840 Speaker 1: speed of light, right, and only massless things can go 319 00:17:03,920 --> 00:17:05,639 Speaker 1: the speed of light, So you can never go the 320 00:17:05,640 --> 00:17:08,080 Speaker 1: speed of lights. Are saying I have much mass, Daniel. 321 00:17:09,119 --> 00:17:12,920 Speaker 1: You're pretty massive, dude, Yeah, by which I mean you're funny, 322 00:17:12,960 --> 00:17:17,080 Speaker 1: and you're massively awesome thanking, and you have a massively 323 00:17:17,400 --> 00:17:20,959 Speaker 1: excellent podcast, and you are brilliant. But you're not entirely 324 00:17:20,960 --> 00:17:23,639 Speaker 1: made of light. But that all right, Yeah, I was 325 00:17:23,680 --> 00:17:28,399 Speaker 1: just fishing for relative compliments. You're absolutely wonderful. So if 326 00:17:28,400 --> 00:17:30,920 Speaker 1: you have somebody in a spaceship and they're going super 327 00:17:30,960 --> 00:17:32,960 Speaker 1: duper fast and they're approaching the speed of light, and 328 00:17:33,080 --> 00:17:35,400 Speaker 1: time slows down further and further, to the point where 329 00:17:35,400 --> 00:17:39,080 Speaker 1: it almost stops. But remember, for them, time doesn't slow down. 330 00:17:39,160 --> 00:17:41,800 Speaker 1: It's not like they're living in molasses. It's just our 331 00:17:41,920 --> 00:17:45,439 Speaker 1: observation of their time. So if somehow a photon had 332 00:17:45,480 --> 00:17:48,840 Speaker 1: a clock, yeah, our view of the photons clock would 333 00:17:48,840 --> 00:17:51,280 Speaker 1: be that it was frozen. Right for us, Photons don't 334 00:17:51,320 --> 00:17:53,679 Speaker 1: move forward in time. They are frozen in time. But 335 00:17:53,720 --> 00:17:57,120 Speaker 1: if you were a photon, what would your experience be. Well, 336 00:17:57,119 --> 00:17:59,080 Speaker 1: it's hard to answer that because you're not a photon, 337 00:17:59,080 --> 00:18:01,639 Speaker 1: and you have to have that concept of like ascension photon, 338 00:18:01,720 --> 00:18:06,200 Speaker 1: which seems impossible, but it's always basically an impossible question 339 00:18:06,200 --> 00:18:09,720 Speaker 1: to answer. But they remember, your time always moves forward 340 00:18:10,119 --> 00:18:16,320 Speaker 1: um at one second per second. Okay, so that's the 341 00:18:16,320 --> 00:18:20,800 Speaker 1: effect of time dilation. Time moves seems to move slower 342 00:18:20,800 --> 00:18:24,680 Speaker 1: when you're going faster. So let's get into why it happens. 343 00:18:24,720 --> 00:18:28,280 Speaker 1: Do we know why this happens. We do know why, 344 00:18:28,440 --> 00:18:32,680 Speaker 1: and it's a consequence of another really strange, counterintuitive thing 345 00:18:32,760 --> 00:18:35,960 Speaker 1: that we've observed about the universe that makes very little sense. 346 00:18:36,760 --> 00:18:40,879 Speaker 1: So it's a conundrum built on a conundrum. It's a bizarre, 347 00:18:41,080 --> 00:18:45,439 Speaker 1: counterintuitive consequence of something really weird about the universe and 348 00:18:45,600 --> 00:18:49,520 Speaker 1: really weird about light. Actually, it's the fact that everybody 349 00:18:49,600 --> 00:18:53,320 Speaker 1: always observes light going at the same speed, no matter 350 00:18:53,400 --> 00:18:57,160 Speaker 1: how fast they're going relative to the source of the light. Okay, 351 00:18:57,240 --> 00:19:00,520 Speaker 1: let's break it down what that means. So light travels 352 00:19:00,560 --> 00:19:04,480 Speaker 1: through space, but nobody can see it move faster than 353 00:19:04,800 --> 00:19:07,359 Speaker 1: that speed that light losing. That's right. There's a certain 354 00:19:07,400 --> 00:19:09,520 Speaker 1: speed of light that goes through space three times ten 355 00:19:09,600 --> 00:19:11,720 Speaker 1: to the eights per second. And we'll call it the 356 00:19:11,720 --> 00:19:14,639 Speaker 1: speed of light. Of course. And if I'm standing on 357 00:19:14,680 --> 00:19:17,480 Speaker 1: a planet and I turn on a flashlight, then the 358 00:19:17,560 --> 00:19:21,280 Speaker 1: light leaves me and travels at three times tended them 359 00:19:21,440 --> 00:19:24,960 Speaker 1: per second away from me. Right, And if I'm and 360 00:19:25,000 --> 00:19:27,120 Speaker 1: if you're shooting it at me, then I see moving 361 00:19:27,160 --> 00:19:29,639 Speaker 1: towards me at three times ten to the eight meters 362 00:19:29,680 --> 00:19:32,320 Speaker 1: per second. Okay, that's right, even if you're even if 363 00:19:32,359 --> 00:19:34,520 Speaker 1: you're on a rocket ship and you're moving towards me, right, 364 00:19:34,720 --> 00:19:36,840 Speaker 1: say you're moving towards me at half the speed of light. 365 00:19:37,480 --> 00:19:40,320 Speaker 1: I shoot my laser beam at you're my flashlight at you, 366 00:19:40,320 --> 00:19:42,480 Speaker 1: you still see that flashlight, the light from it coming 367 00:19:42,480 --> 00:19:44,920 Speaker 1: at you at the speed of light, right, And that's 368 00:19:44,960 --> 00:19:48,040 Speaker 1: different from you know, sound waves or rocks or something, 369 00:19:48,200 --> 00:19:50,919 Speaker 1: or a baseball. Like that's weird. Right, Like, if you 370 00:19:51,000 --> 00:19:54,080 Speaker 1: throw a baseball at me and I'm running full speed 371 00:19:54,080 --> 00:19:57,120 Speaker 1: towards you, that baseball is going to be it's gonna 372 00:19:57,160 --> 00:19:59,600 Speaker 1: look like it's moving really fast towards me. That's right. 373 00:19:59,640 --> 00:20:01,119 Speaker 1: If I threw a baseball at you at a hundred 374 00:20:01,119 --> 00:20:03,199 Speaker 1: miles an hour, which I promise I can totally do, 375 00:20:03,280 --> 00:20:06,399 Speaker 1: this is very realistic, and you're running towards me at 376 00:20:06,440 --> 00:20:10,480 Speaker 1: fifty miles an hour, which I'm sure you're totally capable of. Um, 377 00:20:10,840 --> 00:20:13,760 Speaker 1: then obviously I see the baseball is moving away from 378 00:20:13,800 --> 00:20:15,720 Speaker 1: me at a hundred miles per hour, but you see 379 00:20:15,720 --> 00:20:17,879 Speaker 1: the baseball is coming towards you at a hundred fifty 380 00:20:17,920 --> 00:20:20,119 Speaker 1: miles per hour. Right. That's the way it works for 381 00:20:20,160 --> 00:20:22,639 Speaker 1: normal things. But you're saying that if that baseball instead 382 00:20:22,640 --> 00:20:24,760 Speaker 1: of a baseball, it was a beam of light, that 383 00:20:24,800 --> 00:20:28,240 Speaker 1: wouldn't happen. That's right. Light doesn't follow those rules. Everybody 384 00:20:28,240 --> 00:20:31,359 Speaker 1: who measures it measures it as traveling at that fixed 385 00:20:31,400 --> 00:20:33,480 Speaker 1: speed of light. No matter what. I mean, there are 386 00:20:33,520 --> 00:20:36,280 Speaker 1: caveats here, like it slows down and it travels through 387 00:20:36,320 --> 00:20:38,520 Speaker 1: air or water, whatever, But let's just talk about it 388 00:20:38,520 --> 00:20:41,280 Speaker 1: in a vacuum. The crazy thing is that doesn't matter 389 00:20:41,280 --> 00:20:43,920 Speaker 1: how fast you're going, everybody sees light is traveling at 390 00:20:43,920 --> 00:20:47,359 Speaker 1: this maximum speed of the universe, no matter what. And 391 00:20:47,400 --> 00:20:50,960 Speaker 1: that's crazy, right and right there is where your concept 392 00:20:51,040 --> 00:20:54,000 Speaker 1: that everybody sees the same thing the same way, or 393 00:20:54,000 --> 00:20:57,080 Speaker 1: that there is one absolute truth that we're all observing 394 00:20:57,080 --> 00:21:00,320 Speaker 1: in different ways breaks down because your description of events 395 00:21:00,320 --> 00:21:02,440 Speaker 1: and my description events are going to be very different. 396 00:21:02,560 --> 00:21:05,200 Speaker 1: If we see light moving at different speeds. It's the 397 00:21:05,320 --> 00:21:08,199 Speaker 1: weird It's like a weird rule of the universe. Not 398 00:21:08,359 --> 00:21:11,159 Speaker 1: that light something can't travel at this faster than the 399 00:21:11,200 --> 00:21:13,680 Speaker 1: speed of light. It's a weird rule that says nothing 400 00:21:13,720 --> 00:21:16,400 Speaker 1: can be seen to travel faster than the speed of light, 401 00:21:16,640 --> 00:21:19,080 Speaker 1: not even light. That's right. Light always travels at the 402 00:21:19,119 --> 00:21:21,720 Speaker 1: speed of light, and nothing can travel faster than the 403 00:21:21,720 --> 00:21:23,480 Speaker 1: speed of light. And these two things are connected, right, 404 00:21:23,720 --> 00:21:26,960 Speaker 1: because if light operated the same way as baseballs, then 405 00:21:27,119 --> 00:21:29,400 Speaker 1: you could see light moving as faster than the speed 406 00:21:29,400 --> 00:21:31,639 Speaker 1: of light just by moving towards me. When I'm shooting 407 00:21:31,680 --> 00:21:33,800 Speaker 1: a laser at you, right then that light would be 408 00:21:33,840 --> 00:21:36,240 Speaker 1: moving relative to you. It's faster than the speed of light. 409 00:21:36,320 --> 00:21:38,320 Speaker 1: But it doesn't right, you move towards me, and you 410 00:21:38,359 --> 00:21:41,240 Speaker 1: still measure light as moving at the same speed. It 411 00:21:41,240 --> 00:21:44,120 Speaker 1: doesn't matter if you're running away from me or towards me. Okay, 412 00:21:44,119 --> 00:21:46,040 Speaker 1: So if you shoot a light beam at me and 413 00:21:46,080 --> 00:21:49,359 Speaker 1: I'm running towards you really really, really fast, You're going 414 00:21:49,400 --> 00:21:51,240 Speaker 1: to measure the light moving at the speed of light. 415 00:21:51,960 --> 00:21:54,560 Speaker 1: And I should measure the light moving faster towards me. 416 00:21:54,600 --> 00:21:57,359 Speaker 1: But I'm also going to measure it moving at the 417 00:21:57,359 --> 00:22:00,159 Speaker 1: speed of light, even if I'm moving towards you or 418 00:22:00,160 --> 00:22:02,720 Speaker 1: away from you or to the side of you exactly, 419 00:22:02,960 --> 00:22:05,639 Speaker 1: no matter how fast and moving, I'm always going to 420 00:22:05,680 --> 00:22:07,520 Speaker 1: measure it and moving at the speed of light exactly. 421 00:22:07,920 --> 00:22:11,080 Speaker 1: And that's crazy, right, It's bonkers, doesn't make any sense. 422 00:22:11,200 --> 00:22:13,680 Speaker 1: And it's a famous experiment, Michael said. Morally, the experiment 423 00:22:13,680 --> 00:22:15,760 Speaker 1: that that did this, they shot beams of light in 424 00:22:15,800 --> 00:22:19,000 Speaker 1: two directions, and because the earth is moving, they figured, well, 425 00:22:19,000 --> 00:22:20,320 Speaker 1: one of them is going to go slower than the 426 00:22:20,359 --> 00:22:22,959 Speaker 1: other one because the earth is moving, right, So they 427 00:22:22,960 --> 00:22:25,440 Speaker 1: did the experiment different times of year, and the light 428 00:22:25,480 --> 00:22:28,159 Speaker 1: came back took the same amount of time to go 429 00:22:28,200 --> 00:22:31,800 Speaker 1: in these two perpendicular directions every single time. And that 430 00:22:31,880 --> 00:22:35,120 Speaker 1: told them that that the speed at which light travels 431 00:22:35,359 --> 00:22:38,320 Speaker 1: is not dependent on how fast you are moving the 432 00:22:38,320 --> 00:22:41,840 Speaker 1: observer is moving. It's always the same speed. It's crazy. 433 00:22:42,080 --> 00:22:45,120 Speaker 1: Is it like some kind of um just like fundamental 434 00:22:45,880 --> 00:22:49,600 Speaker 1: limit in this stuff of the universe itself? You know, 435 00:22:49,680 --> 00:22:53,040 Speaker 1: like nothing can propagate through this thing we call space 436 00:22:53,119 --> 00:22:55,240 Speaker 1: faster than the speed of light. Is that kind of 437 00:22:55,280 --> 00:22:57,720 Speaker 1: what it's related to. Yeah, definitely, But it's it's a 438 00:22:57,720 --> 00:23:00,160 Speaker 1: deep question and we don't have a solid answer to too. 439 00:23:00,680 --> 00:23:03,760 Speaker 1: Why does light always travel at this speed regardless of 440 00:23:03,760 --> 00:23:05,800 Speaker 1: the speed of the observer. We don't know the answer 441 00:23:05,800 --> 00:23:09,360 Speaker 1: to that. That's just like Einstein postulated that. He said, Okay, 442 00:23:09,600 --> 00:23:12,800 Speaker 1: let's start from this crazy assumption and build the math 443 00:23:12,920 --> 00:23:15,399 Speaker 1: up from there, and if everything then works, and we'll say, well, 444 00:23:15,440 --> 00:23:17,800 Speaker 1: that assumption must be true. And if you start from 445 00:23:17,800 --> 00:23:20,760 Speaker 1: that assumption, you get all sorts of crazy predictions which 446 00:23:20,800 --> 00:23:24,000 Speaker 1: all turn out to be true. Right, So that is 447 00:23:24,000 --> 00:23:25,920 Speaker 1: a deep truth of the universe. But the answer is, 448 00:23:26,000 --> 00:23:28,480 Speaker 1: we don't know why. We don't know why light always 449 00:23:28,560 --> 00:23:31,040 Speaker 1: travels at the same speed, or a light is always 450 00:23:31,040 --> 00:23:33,600 Speaker 1: observed at the same speed, no matter who is doing 451 00:23:33,600 --> 00:23:37,080 Speaker 1: the measuring and how fast they're going. It's a weird 452 00:23:37,200 --> 00:23:39,520 Speaker 1: rule about the universe. It's a weird, weird rule. And 453 00:23:39,560 --> 00:23:41,280 Speaker 1: when I meet the people who wrote the simulation, I'm 454 00:23:41,280 --> 00:23:43,480 Speaker 1: gonna ask them, why did you do that, man that 455 00:23:43,560 --> 00:23:50,000 Speaker 1: made everything so complicated about the universe? One star on 456 00:23:50,160 --> 00:23:53,440 Speaker 1: Yelp for that for that bit of load. No, I 457 00:23:53,440 --> 00:23:56,280 Speaker 1: think it's it's there's a fascinating angle there, you know, 458 00:23:56,359 --> 00:23:58,800 Speaker 1: because we grew up sort of as a species in 459 00:23:58,840 --> 00:24:01,080 Speaker 1: an environment where nothing was near the speed of light, 460 00:24:01,520 --> 00:24:04,200 Speaker 1: and so we never noticed this, and so we assume 461 00:24:04,400 --> 00:24:07,040 Speaker 1: things like everybody's clock runs at the same time because 462 00:24:07,080 --> 00:24:09,960 Speaker 1: we've always thought it did. And so they're not allowed 463 00:24:10,000 --> 00:24:12,000 Speaker 1: us to assume things like there must be some sort 464 00:24:12,040 --> 00:24:15,600 Speaker 1: of absolute sense of time and absolute history and there's 465 00:24:15,600 --> 00:24:18,000 Speaker 1: a really universe out there, and this is I mean, 466 00:24:18,000 --> 00:24:21,240 Speaker 1: this shakes the very foundations of how we even think 467 00:24:21,240 --> 00:24:23,440 Speaker 1: about the universe that's out there and whether it makes 468 00:24:23,440 --> 00:24:26,240 Speaker 1: sense at all. So it's it's pretty crazy stuff. I 469 00:24:26,240 --> 00:24:29,560 Speaker 1: feel like we're kepped with weirdness at both ends of 470 00:24:29,600 --> 00:24:33,160 Speaker 1: the specter. What I mean is like, if you move 471 00:24:33,200 --> 00:24:34,920 Speaker 1: it close to the speed of light, things get weird. 472 00:24:35,080 --> 00:24:37,680 Speaker 1: But also if you don't move at all, things good weird. 473 00:24:37,760 --> 00:24:41,160 Speaker 1: Right because of quantum physics and the uncertainty principle. Right, 474 00:24:41,200 --> 00:24:44,000 Speaker 1: Like if you try to discertain things that zero velocity, 475 00:24:44,080 --> 00:24:46,360 Speaker 1: things get weird too. Things always get weird. I think 476 00:24:46,400 --> 00:24:49,399 Speaker 1: that's the takeaway, right. The universe is weird, like I 477 00:24:49,400 --> 00:24:51,960 Speaker 1: think I said last week, is weirder and stranger and 478 00:24:52,000 --> 00:24:54,880 Speaker 1: hotter and nastier and wetter than you could ever even imagine. 479 00:24:55,359 --> 00:24:57,840 Speaker 1: And the I think the craziest surprises about the way 480 00:24:57,880 --> 00:25:00,320 Speaker 1: the universe work are still yet to come. You know, 481 00:25:00,359 --> 00:25:02,840 Speaker 1: we've made these discoveries that showed us to the universe 482 00:25:02,920 --> 00:25:05,880 Speaker 1: is so different from the way our ancestors have imagined. 483 00:25:06,200 --> 00:25:08,440 Speaker 1: There must be more of those discoveries coming. It's certainly 484 00:25:08,480 --> 00:25:10,640 Speaker 1: not the case that we figured them all out. There 485 00:25:10,680 --> 00:25:13,919 Speaker 1: are crazy revelations in our future. Well, that's good for 486 00:25:13,960 --> 00:25:19,159 Speaker 1: our podcast topics, that's right. Okay, let's so let's get 487 00:25:19,200 --> 00:25:22,560 Speaker 1: into how this affects time. But first let's take a 488 00:25:22,600 --> 00:25:37,680 Speaker 1: quick break. So we know that the speed of light, 489 00:25:37,960 --> 00:25:40,360 Speaker 1: you can observe going anything faster than the speed of light. 490 00:25:40,760 --> 00:25:42,840 Speaker 1: So how does this affect how we view time or 491 00:25:42,840 --> 00:25:45,720 Speaker 1: how we experience time? Right, So it comes directly the 492 00:25:46,160 --> 00:25:49,080 Speaker 1: fact that light can't travel at any other speed is 493 00:25:49,119 --> 00:25:52,360 Speaker 1: what directly affects how time passes and how we measure time. 494 00:25:53,040 --> 00:25:55,480 Speaker 1: And it can be a complicated topic, but I think 495 00:25:55,680 --> 00:25:57,280 Speaker 1: the best way to do is to think about maybe 496 00:25:57,320 --> 00:25:59,960 Speaker 1: how a simple clock operates. So let's build a simple 497 00:26:00,080 --> 00:26:04,440 Speaker 1: clock that uses light. You mean like an Apple watch? Er, No, 498 00:26:04,560 --> 00:26:06,640 Speaker 1: I mean let's imagine that you're you have to build 499 00:26:06,640 --> 00:26:08,440 Speaker 1: a clock, and all you have as a laser, right, 500 00:26:08,840 --> 00:26:12,520 Speaker 1: And so you know, for example, that light takes about 501 00:26:13,000 --> 00:26:17,119 Speaker 1: ten nanoseconds to go ten feet right, it goes about 502 00:26:17,160 --> 00:26:20,240 Speaker 1: one ft every nanosecond. So what you do is you 503 00:26:20,480 --> 00:26:24,280 Speaker 1: measure very precisely, you know, ten ft. You put a 504 00:26:24,280 --> 00:26:26,520 Speaker 1: mirror at the end, and then you shoot your laser. 505 00:26:26,520 --> 00:26:29,280 Speaker 1: You shoot a laser pulse, and you say, however long 506 00:26:29,320 --> 00:26:34,040 Speaker 1: it takes to go um there and back. That's two seconds, right, 507 00:26:34,040 --> 00:26:36,199 Speaker 1: ten feet there and ten feetback. And you set up 508 00:26:36,200 --> 00:26:38,960 Speaker 1: the mirrors in the floor and in the ceiling, right, 509 00:26:38,960 --> 00:26:42,120 Speaker 1: so that being is bouncing up and down right right, 510 00:26:42,160 --> 00:26:45,040 Speaker 1: So you you shoot the laser up towards the ceiling 511 00:26:45,119 --> 00:26:47,960 Speaker 1: and back, and you know how far it is to 512 00:26:48,000 --> 00:26:50,000 Speaker 1: your ceiling and how far it is back to your floor, 513 00:26:50,080 --> 00:26:52,800 Speaker 1: and so you say that's twenty ft, so that's two 514 00:26:52,840 --> 00:26:55,480 Speaker 1: seconds round trip. Oh I see. So then the way 515 00:26:55,520 --> 00:26:58,200 Speaker 1: you turn that into a clock is you count how 516 00:26:58,240 --> 00:27:01,719 Speaker 1: many times the light bounces up and down the ceiling, 517 00:27:01,960 --> 00:27:03,880 Speaker 1: and that sort of gives you a sense of how 518 00:27:04,359 --> 00:27:06,640 Speaker 1: time is moving. That's right. You want to say, well, 519 00:27:06,680 --> 00:27:09,639 Speaker 1: how long does it take my cat to finish his lunch? 520 00:27:09,760 --> 00:27:12,000 Speaker 1: And so you count how many times it takes the 521 00:27:12,080 --> 00:27:13,880 Speaker 1: laser pults to go up to the ceiling and back, 522 00:27:14,280 --> 00:27:16,560 Speaker 1: and that's the number of two second intervals it takes 523 00:27:16,560 --> 00:27:19,320 Speaker 1: your cat to eat his lunch. Okay, so that's where 524 00:27:19,440 --> 00:27:23,880 Speaker 1: it seems like a pretty impractical clock. But hey, this 525 00:27:23,880 --> 00:27:25,800 Speaker 1: this is how we do things in physics. Man, be like, 526 00:27:26,080 --> 00:27:31,480 Speaker 1: can we build this thing using lasers? What's the most 527 00:27:31,520 --> 00:27:35,480 Speaker 1: inconvenient wristwatch we can build with lasers at home? The 528 00:27:35,520 --> 00:27:38,119 Speaker 1: way we toast bread for breakfast as we use lasers, 529 00:27:38,320 --> 00:27:42,760 Speaker 1: of course, and cats cats, I feel like it's a key. No, 530 00:27:42,920 --> 00:27:47,040 Speaker 1: that's just how we toast our cats. Man. Let's say 531 00:27:47,080 --> 00:27:48,840 Speaker 1: you cooked the food for the I want to I 532 00:27:48,880 --> 00:27:51,440 Speaker 1: want to officially distance myself from that joke, because nobody 533 00:27:51,440 --> 00:27:54,080 Speaker 1: should ever fire a laser at a cat. Well, you 534 00:27:54,080 --> 00:27:56,359 Speaker 1: can fire a laser near a cat to entertain it, 535 00:27:56,400 --> 00:27:58,200 Speaker 1: of course, but I don't actually hit your your cat 536 00:27:58,200 --> 00:28:00,719 Speaker 1: with a laser, please, oh man? All right, So now 537 00:28:00,800 --> 00:28:02,600 Speaker 1: we have our clock, right, that's the way a clock 538 00:28:02,680 --> 00:28:05,000 Speaker 1: that uses light. Okay, so this is a thought experiment. 539 00:28:05,000 --> 00:28:07,280 Speaker 1: We're going to build a clock where we measure time 540 00:28:07,320 --> 00:28:09,840 Speaker 1: by measuring counting how many times it bounces off the 541 00:28:09,840 --> 00:28:12,080 Speaker 1: ceiling up and down. That's right, And it doesn't have 542 00:28:12,119 --> 00:28:14,280 Speaker 1: to be a thought experiment. You've got mirrors, you've got lasers. 543 00:28:14,440 --> 00:28:17,520 Speaker 1: Go ahead, build your self o'clock. Um. But the interesting 544 00:28:17,560 --> 00:28:20,000 Speaker 1: thing is that what happens if you put that clock 545 00:28:20,119 --> 00:28:23,439 Speaker 1: on a spaceship right right on the train. Let's make 546 00:28:23,480 --> 00:28:28,760 Speaker 1: it even more inconvenient. Let's put this on a spaceship. 547 00:28:29,640 --> 00:28:31,879 Speaker 1: And so that's when things start to get interesting, right, Like, 548 00:28:31,960 --> 00:28:35,000 Speaker 1: that's when we start to see how time slows down. Yeah, 549 00:28:35,080 --> 00:28:37,160 Speaker 1: Or let's put the clock on the back of your cat, right, 550 00:28:37,760 --> 00:28:39,680 Speaker 1: and then see what happens when you're well, I guess 551 00:28:39,960 --> 00:28:41,520 Speaker 1: you need the ceiling on the back of the cap. 552 00:28:41,560 --> 00:28:43,640 Speaker 1: Maybe that doesn't. Actually, I feel like trying to get 553 00:28:43,640 --> 00:28:45,720 Speaker 1: a cat to do what you want is even more 554 00:28:46,400 --> 00:28:49,080 Speaker 1: difficult than getting on a spaceship. Einstein had no idea 555 00:28:49,120 --> 00:28:50,520 Speaker 1: how to get your cat to do what you want. 556 00:28:50,560 --> 00:28:53,000 Speaker 1: You can master. He was the master of the cosmos, 557 00:28:53,080 --> 00:28:59,200 Speaker 1: but not of cats. All right. So we have a 558 00:28:59,200 --> 00:29:02,800 Speaker 1: clock where you measure time by counting how many times 559 00:29:02,840 --> 00:29:04,760 Speaker 1: it bounced off the ceiling on the floor, and we 560 00:29:04,840 --> 00:29:07,520 Speaker 1: stick it in a spaceship, and then we start going. 561 00:29:07,600 --> 00:29:10,280 Speaker 1: What happens then, right, So if you're in the spaceship, 562 00:29:10,480 --> 00:29:13,040 Speaker 1: nothing changes. It doesn't matter that you're going at half 563 00:29:13,040 --> 00:29:14,800 Speaker 1: the speed of light or nine tenths of speed of light. 564 00:29:15,000 --> 00:29:17,560 Speaker 1: You're in the spaceship. You have no velocity relative to 565 00:29:17,600 --> 00:29:19,320 Speaker 1: the clock. So things work the same way on the 566 00:29:19,320 --> 00:29:21,880 Speaker 1: spaceship for you as they did when you tested your 567 00:29:21,880 --> 00:29:23,720 Speaker 1: clock in your living room. As you just see the 568 00:29:23,720 --> 00:29:25,640 Speaker 1: beam go up and down, bounce up and down, and 569 00:29:25,680 --> 00:29:27,800 Speaker 1: you count, and that's your time. That's right. And since 570 00:29:27,840 --> 00:29:29,520 Speaker 1: you brought your cat along, it takes your cat the 571 00:29:29,520 --> 00:29:31,640 Speaker 1: same amount of time to eat his lunch in your 572 00:29:31,640 --> 00:29:35,000 Speaker 1: spaceship as it does at home, assuming he's not wearing 573 00:29:35,040 --> 00:29:38,120 Speaker 1: a silly cat space suit. The interesting thing is that 574 00:29:38,200 --> 00:29:40,600 Speaker 1: when since you left me, Um, you left me on Earth, 575 00:29:40,640 --> 00:29:42,959 Speaker 1: you didn't invite me on your awesome spaceship. Thanks by 576 00:29:43,000 --> 00:29:47,800 Speaker 1: the way, that would have been too inconvenient. And I'm 577 00:29:47,920 --> 00:29:50,280 Speaker 1: so heartbroken that I'm spying on you. Have a massive 578 00:29:50,320 --> 00:29:54,160 Speaker 1: telescope and I'm watching your cat eat lunch on a spaceship. Um. 579 00:29:54,240 --> 00:29:56,760 Speaker 1: Now I'm looking at your clock, okay, and I'm wondering 580 00:29:56,760 --> 00:29:59,280 Speaker 1: how long does it take his cat to eat lunch, etcetera. 581 00:30:00,480 --> 00:30:03,800 Speaker 1: And I'm watching your clock. Okay, you're trying to count 582 00:30:03,880 --> 00:30:07,240 Speaker 1: how many times it bounces off the ceiling to exactly. 583 00:30:07,680 --> 00:30:09,720 Speaker 1: So I see the laser pulse go up, and I 584 00:30:09,760 --> 00:30:12,880 Speaker 1: see the laser pulse come down. Right. The problem is 585 00:30:12,960 --> 00:30:15,560 Speaker 1: that I don't see the laser pulse going ten feet 586 00:30:15,640 --> 00:30:18,160 Speaker 1: up and ten feet down. I see the laser pulse 587 00:30:18,320 --> 00:30:21,680 Speaker 1: as going further because you're moving, which means the laser 588 00:30:21,720 --> 00:30:23,600 Speaker 1: pulse is not just going up and down. It's also 589 00:30:23,720 --> 00:30:26,760 Speaker 1: going sideways in the direction of your motion. So you 590 00:30:26,840 --> 00:30:29,240 Speaker 1: have the up and down and the sideways. So the 591 00:30:29,320 --> 00:30:31,640 Speaker 1: light for me, the laser is going in a diagonal right, 592 00:30:31,680 --> 00:30:34,920 Speaker 1: diagonal up hit the ceiling, and diagonal back down to 593 00:30:35,080 --> 00:30:37,600 Speaker 1: hit the floor, because you see it hit the ceiling 594 00:30:38,160 --> 00:30:41,720 Speaker 1: and then on its way down, the spaceship is awesome moving, 595 00:30:41,760 --> 00:30:45,480 Speaker 1: so it's kind of moving diagonally to hit the floor 596 00:30:45,520 --> 00:30:48,040 Speaker 1: where it's going to be exactly. And so the mirrors 597 00:30:48,040 --> 00:30:50,160 Speaker 1: and the clock move with the laser. Obviously they're all 598 00:30:50,160 --> 00:30:53,240 Speaker 1: going at the same speed sideways, and so the laser 599 00:30:53,280 --> 00:30:55,040 Speaker 1: beam hits the mirror on the top and it hits 600 00:30:55,080 --> 00:30:57,320 Speaker 1: the receiver or whatever on the bottom. But I see 601 00:30:57,320 --> 00:31:00,480 Speaker 1: you traveling further than you do, right, And this is 602 00:31:00,520 --> 00:31:03,440 Speaker 1: where the the absolute speed of light kicks in because 603 00:31:03,920 --> 00:31:06,720 Speaker 1: you say, okay, travel ten feet, right. It traveled those 604 00:31:06,760 --> 00:31:08,160 Speaker 1: ten feet at the speed of light, So I know 605 00:31:08,240 --> 00:31:11,479 Speaker 1: it takes ten seconds, but I see it traveled further. Right, 606 00:31:11,480 --> 00:31:13,400 Speaker 1: Depending on how fast you're going, it could have traveled 607 00:31:13,400 --> 00:31:17,760 Speaker 1: like fourteen fifteen feet, right, because light always travels at 608 00:31:17,800 --> 00:31:21,000 Speaker 1: the same speed. Right, I see it taking longer because 609 00:31:21,040 --> 00:31:24,040 Speaker 1: it's gone further and it can go faster than the 610 00:31:24,080 --> 00:31:26,240 Speaker 1: speed of light. It can go faster than the speed 611 00:31:26,240 --> 00:31:28,520 Speaker 1: of light. So I see your clock running slower. It 612 00:31:28,600 --> 00:31:33,560 Speaker 1: literally takes longer to count off seconds for you because 613 00:31:33,600 --> 00:31:35,720 Speaker 1: the clock is built on the premise that it takes 614 00:31:35,800 --> 00:31:38,160 Speaker 1: light a certain time to go a certain distance. But 615 00:31:38,160 --> 00:31:40,920 Speaker 1: now that distance is further and the speed can't change 616 00:31:40,960 --> 00:31:42,520 Speaker 1: because it's going up and down. The light is going 617 00:31:42,600 --> 00:31:45,400 Speaker 1: up and down, and it's trying to go forward to exactly, 618 00:31:45,400 --> 00:31:48,320 Speaker 1: so it has to take longer exactly. Now, if you 619 00:31:48,400 --> 00:31:51,239 Speaker 1: built this same kind of clock using something else, like 620 00:31:51,400 --> 00:31:54,400 Speaker 1: sound waves, right, you had a speaker, then this wouldn't 621 00:31:54,400 --> 00:31:57,040 Speaker 1: happen because the sound waves don't have that same property 622 00:31:57,080 --> 00:31:59,520 Speaker 1: that they always travel at the speed at a certain 623 00:31:59,560 --> 00:32:03,360 Speaker 1: speed relative to observers. Right. Um, sound waves, as we 624 00:32:03,360 --> 00:32:06,200 Speaker 1: know from Doppler shifts, change their speed based on how 625 00:32:06,200 --> 00:32:08,440 Speaker 1: fast you're going. So if this is a sound wave, 626 00:32:08,520 --> 00:32:10,360 Speaker 1: if we use sound waves instead, then I would just 627 00:32:10,400 --> 00:32:13,480 Speaker 1: see the sound waves is traveling faster. But light can't 628 00:32:13,520 --> 00:32:15,680 Speaker 1: do that. Light always travels to the same speed no 629 00:32:15,760 --> 00:32:18,880 Speaker 1: matter who the observer is. So it slows your clock down. 630 00:32:19,160 --> 00:32:21,960 Speaker 1: So let's let's go back a step. Um. Okay, So 631 00:32:21,960 --> 00:32:24,160 Speaker 1: so I'm gonna be in my spaceship counting how many 632 00:32:24,160 --> 00:32:26,160 Speaker 1: times it bounces off the ceiling, and for me, it's 633 00:32:26,160 --> 00:32:29,040 Speaker 1: going to be like bounce, bounce, bounce, bounce, bounds. But 634 00:32:29,160 --> 00:32:33,000 Speaker 1: for you, you're saying because it has to travel up 635 00:32:33,000 --> 00:32:35,880 Speaker 1: and down and forward. You're going to count it slower, 636 00:32:35,960 --> 00:32:39,920 Speaker 1: right like for you, it's going to be bounds, bounds, bounds, 637 00:32:40,040 --> 00:32:45,120 Speaker 1: And so that's kind of the definition of time. Yeah, exactly, exactly, 638 00:32:45,120 --> 00:32:47,680 Speaker 1: and any clock. And you're thinking, okay, well, that's just 639 00:32:47,840 --> 00:32:51,200 Speaker 1: one example, right, But the same argument holds for if 640 00:32:51,240 --> 00:32:53,080 Speaker 1: you're going in another direction, right, you don't have just 641 00:32:53,160 --> 00:32:56,160 Speaker 1: be going sideways. If you're shooting in the direction of 642 00:32:56,160 --> 00:32:58,880 Speaker 1: the mirror, right, then the light has longer to go 643 00:32:58,920 --> 00:33:01,240 Speaker 1: in one direction, but it can't make up the time. 644 00:33:01,960 --> 00:33:04,200 Speaker 1: And if you're going at an angle, the same thing happens. 645 00:33:04,560 --> 00:33:07,280 Speaker 1: And also for any clock. This is just one example. 646 00:33:07,280 --> 00:33:09,959 Speaker 1: It's the clearest example because we've built it out of 647 00:33:10,000 --> 00:33:13,080 Speaker 1: something that only uses light, but the true the same 648 00:33:13,120 --> 00:33:17,120 Speaker 1: happens for every physical process, for any kind of clock. Okay. 649 00:33:17,120 --> 00:33:20,920 Speaker 1: So that's kind of the explanation is that time, the 650 00:33:21,040 --> 00:33:24,760 Speaker 1: definition of time is sort of tied to the speed 651 00:33:24,800 --> 00:33:28,320 Speaker 1: of light, and the universe has this weird rule about 652 00:33:28,360 --> 00:33:30,400 Speaker 1: the speed of light, which is that nobody can never 653 00:33:30,440 --> 00:33:32,760 Speaker 1: see it move faster than the speed of light. That's right, 654 00:33:33,040 --> 00:33:35,120 Speaker 1: And the other important thing to understand is that your 655 00:33:35,120 --> 00:33:39,120 Speaker 1: definition of time and your definition of what happens depends 656 00:33:39,360 --> 00:33:41,680 Speaker 1: on how fast you are going. There is no absolute 657 00:33:41,680 --> 00:33:44,080 Speaker 1: sense of time. It's not like the universe has a 658 00:33:44,080 --> 00:33:46,400 Speaker 1: big clock out there and it's keeping track of what's 659 00:33:46,400 --> 00:33:48,880 Speaker 1: going on, and we're trying to make measures of measurements 660 00:33:48,920 --> 00:33:50,400 Speaker 1: of it, and they're kind of sloppy sometimes when we 661 00:33:50,440 --> 00:33:54,200 Speaker 1: get them wrong, Like there is no absolute sense of time, right, 662 00:33:54,280 --> 00:33:57,560 Speaker 1: And you can do crazy experiments where you know, depending 663 00:33:57,600 --> 00:34:00,920 Speaker 1: on how fast people are going relative to experiment, they 664 00:34:00,960 --> 00:34:03,680 Speaker 1: can see the order of events changing, like I can 665 00:34:03,680 --> 00:34:06,040 Speaker 1: see A happen before B, and you can see B 666 00:34:06,200 --> 00:34:08,600 Speaker 1: happen before A because you're zooming in the other direction. 667 00:34:09,239 --> 00:34:12,280 Speaker 1: And you might think, well, that's impossible either A happened 668 00:34:12,320 --> 00:34:14,600 Speaker 1: before B or BE happened before A. There is a 669 00:34:14,640 --> 00:34:17,719 Speaker 1: real truth, right, answer is there is no truth. The 670 00:34:17,719 --> 00:34:19,919 Speaker 1: truth is not out there. X Files was a lie. 671 00:34:21,000 --> 00:34:22,520 Speaker 1: So I feel like we should get into that in 672 00:34:22,560 --> 00:34:25,200 Speaker 1: another episode. But I think the conclusion we're reaching here 673 00:34:25,320 --> 00:34:30,000 Speaker 1: is that basically there is no time. After all, there's 674 00:34:30,000 --> 00:34:32,279 Speaker 1: no time to talk about this anymore. And that's true. No, 675 00:34:32,400 --> 00:34:34,520 Speaker 1: there is time, but time is a different thing that 676 00:34:34,600 --> 00:34:37,400 Speaker 1: you than you thought it was, right, It's something weirder 677 00:34:37,440 --> 00:34:40,760 Speaker 1: and more malleable now in our safe, little slow worlds, 678 00:34:40,880 --> 00:34:43,279 Speaker 1: it doesn't. You can pretend that time is the way 679 00:34:43,320 --> 00:34:45,480 Speaker 1: you thought it was right and you'll get by just fine. 680 00:34:46,000 --> 00:34:48,200 Speaker 1: But in reality, if you want to understand the way 681 00:34:48,239 --> 00:34:51,120 Speaker 1: that that physics works at its deepest level, whether universe 682 00:34:51,200 --> 00:34:53,840 Speaker 1: is actually put together, what the real rules are, that 683 00:34:53,960 --> 00:34:56,680 Speaker 1: it turns out time is really different than you thought 684 00:34:56,680 --> 00:34:59,600 Speaker 1: it was. So that person who answered there is no 685 00:34:59,719 --> 00:35:02,759 Speaker 1: time sort of, I feel like she skipped ahead to 686 00:35:02,880 --> 00:35:05,120 Speaker 1: the end of this count. She's probably a physicist visiting 687 00:35:05,120 --> 00:35:10,320 Speaker 1: from the future from Alpha centri. Is it her? Or 688 00:35:10,880 --> 00:35:14,520 Speaker 1: she's your cat evolved for thousands of years into a 689 00:35:14,520 --> 00:35:16,760 Speaker 1: future physicist and then traveled back in time to deliver 690 00:35:16,800 --> 00:35:22,080 Speaker 1: that message. I think she's your twin Danny. Maybe she is, 691 00:35:22,160 --> 00:35:25,040 Speaker 1: maybe she is. Well, speaking of time, I think we're 692 00:35:25,040 --> 00:35:27,640 Speaker 1: out of time for this episode, so it's time to 693 00:35:27,680 --> 00:35:29,759 Speaker 1: wrap it up. Thank you everyone for your patients and 694 00:35:29,800 --> 00:35:32,320 Speaker 1: for listening, And if you have questions about how things 695 00:35:32,320 --> 00:35:35,799 Speaker 1: work in the universe or anything else crazy, please send 696 00:35:35,800 --> 00:35:38,240 Speaker 1: them to us on Twitter or email us at feedback 697 00:35:38,280 --> 00:35:42,680 Speaker 1: at Daniel and Jorge dot com. We love listener questions. Yeah, 698 00:35:42,719 --> 00:35:45,279 Speaker 1: hopefully We made time move a little bit faster for you, 699 00:35:45,400 --> 00:35:48,839 Speaker 1: whatever it is you're doing, unless you were bored, which 700 00:35:49,080 --> 00:36:01,320 Speaker 1: is probably canceled out. If you still have a question 701 00:36:01,360 --> 00:36:04,799 Speaker 1: after listening to all these explanations, please drop us a line. 702 00:36:04,840 --> 00:36:06,960 Speaker 1: We'd love to hear from you. You can find us 703 00:36:07,000 --> 00:36:10,799 Speaker 1: at Facebook, Twitter, and Instagram at Daniel and Jorge That's 704 00:36:10,800 --> 00:36:14,200 Speaker 1: one word, or email us at Feedback at Daniel and 705 00:36:14,400 --> 00:36:24,400 Speaker 1: Orge dot com.