1 00:00:05,800 --> 00:00:09,440 Speaker 1: Some of the most amazing moments in science were totally unexpected. 2 00:00:09,640 --> 00:00:13,680 Speaker 1: You mean, like the discovery of microwave ovens or slinky 3 00:00:13,760 --> 00:00:16,200 Speaker 1: So I heard it was also discovered by accident. Yeah, 4 00:00:16,280 --> 00:00:17,920 Speaker 1: but I'm thinking about the times when you go out 5 00:00:17,960 --> 00:00:20,040 Speaker 1: there just to double check something, something you thought you 6 00:00:20,079 --> 00:00:22,680 Speaker 1: already understood, but you find an answer which makes no 7 00:00:22,760 --> 00:00:25,360 Speaker 1: sense and forced you to change how you'd see things. Yeah. 8 00:00:25,400 --> 00:00:27,600 Speaker 1: Like I heard one of the most fundamental things in 9 00:00:27,640 --> 00:00:31,240 Speaker 1: the universe was actually discovered this way by accident, and 10 00:00:31,400 --> 00:00:33,879 Speaker 1: it's totally amazing. It makes me wish that I had 11 00:00:33,920 --> 00:00:36,640 Speaker 1: been involved, and it makes us see the universe differently, 12 00:00:36,720 --> 00:00:39,599 Speaker 1: makes us see everything differently. Is it more impressive than 13 00:00:39,640 --> 00:00:42,960 Speaker 1: as slinky in a microwave? That's pretty hard to top, 14 00:00:43,200 --> 00:00:58,600 Speaker 1: but I think this one does. Hi, I'm RhE make cartoonists, 15 00:00:58,760 --> 00:01:01,560 Speaker 1: and I'm Daniel. I'm a article physicists, and this is 16 00:01:01,600 --> 00:01:06,440 Speaker 1: our podcast. Daniel and Jorgey explain the universe today on 17 00:01:06,480 --> 00:01:13,080 Speaker 1: the program. What is dark energy and why is it 18 00:01:13,280 --> 00:01:18,000 Speaker 1: everywhere in filling the universe? Is it powerful? Is it dangerous? 19 00:01:18,440 --> 00:01:20,880 Speaker 1: Is it dark after all? Will it stain your clothes? 20 00:01:21,959 --> 00:01:25,919 Speaker 1: And most important, why is it causing the universe to explode. 21 00:01:26,120 --> 00:01:28,840 Speaker 1: The universe is exploding, people, but don't get out of 22 00:01:28,840 --> 00:01:31,559 Speaker 1: your cars. It's going to take a while. Dark energy 23 00:01:31,600 --> 00:01:34,240 Speaker 1: is a mysterious topic. We went around and we asked people, 24 00:01:34,319 --> 00:01:37,200 Speaker 1: what do you know about dark energy? Um, is it 25 00:01:37,319 --> 00:01:39,760 Speaker 1: like empty space? I'm not sure. No, I have no 26 00:01:39,840 --> 00:01:44,000 Speaker 1: idea about it. It's like empty energy. Is dark energy 27 00:01:44,080 --> 00:01:47,200 Speaker 1: something with black holes? I don't know, but that's my speculation. 28 00:01:48,400 --> 00:01:50,960 Speaker 1: So most people really seem to have almost no idea 29 00:01:51,000 --> 00:01:54,040 Speaker 1: what dark energy is, which as a physicist, really surprised 30 00:01:54,040 --> 00:01:56,360 Speaker 1: me because it's one of the most dramatic and amazing 31 00:01:56,400 --> 00:01:59,840 Speaker 1: discoveries of the last thirty years. Yeah, it's but people 32 00:02:00,000 --> 00:02:01,680 Speaker 1: what it has seemed to have heard about it, right, 33 00:02:01,720 --> 00:02:04,600 Speaker 1: It sounded really familiar, but they didn't know what it was. Yeah, 34 00:02:04,640 --> 00:02:06,920 Speaker 1: some people thought it was dark matter. Some people maybe 35 00:02:06,960 --> 00:02:09,839 Speaker 1: thought it was something in black panther like. People really 36 00:02:09,880 --> 00:02:12,200 Speaker 1: didn't seem to have a good grip on what dark 37 00:02:12,280 --> 00:02:14,560 Speaker 1: energy is, which is amazing, not just because it was 38 00:02:14,600 --> 00:02:18,040 Speaker 1: a big discovery, but because it has huge consequences for 39 00:02:18,160 --> 00:02:21,480 Speaker 1: our lives. Yeah, it's a great name. I mean, I 40 00:02:21,520 --> 00:02:23,639 Speaker 1: think it's easy to see why people would confuse it 41 00:02:23,680 --> 00:02:26,640 Speaker 1: with dark matter, they're both dark and that's right. It 42 00:02:26,720 --> 00:02:29,320 Speaker 1: is a cool name, dark energy. It sounds so mysterious, though, 43 00:02:29,320 --> 00:02:31,560 Speaker 1: you're right. In the in like the HR meeting where 44 00:02:31,560 --> 00:02:34,000 Speaker 1: they decided what to call this weird physics thing, it 45 00:02:34,040 --> 00:02:36,079 Speaker 1: should have considered the fact that dark matter and dark 46 00:02:36,160 --> 00:02:38,240 Speaker 1: energy sounded like. I wonder if they do focus groups 47 00:02:38,240 --> 00:02:39,600 Speaker 1: when they do that kind of thing. Do you think 48 00:02:39,600 --> 00:02:41,720 Speaker 1: they thought, Hey, all those dark matter people get a 49 00:02:41,760 --> 00:02:44,560 Speaker 1: ton of grant money. If we call our stark energy, 50 00:02:45,000 --> 00:02:47,160 Speaker 1: we could also get some of that money. I'm sure. 51 00:02:47,480 --> 00:02:50,240 Speaker 1: I'm sure that was the number one concern in their minds. Yeah, 52 00:02:50,320 --> 00:02:55,240 Speaker 1: how will this play in my next grand proposal? Anyway? 53 00:02:55,280 --> 00:02:57,560 Speaker 1: Let's tell people what dark energy is and why it's 54 00:02:57,600 --> 00:03:00,000 Speaker 1: so important. Yeah, well, first of all, it's a huge, 55 00:03:00,040 --> 00:03:02,880 Speaker 1: huge deal, right, Like, it's not like an obscure thing 56 00:03:03,040 --> 00:03:05,880 Speaker 1: in physics. It's like a huge part of the universe. 57 00:03:06,120 --> 00:03:08,639 Speaker 1: That's right. Most of the energy and the universe is 58 00:03:08,639 --> 00:03:13,520 Speaker 1: actually taken up with dark energy, like sixties, right, that's right. Fully, 59 00:03:13,600 --> 00:03:16,239 Speaker 1: two thirds of all the energy in the universe is 60 00:03:16,280 --> 00:03:20,080 Speaker 1: devoted to this weird, mysterious force called dark energy, and 61 00:03:20,120 --> 00:03:22,040 Speaker 1: that's about all we know about it. Like when you 62 00:03:22,080 --> 00:03:25,920 Speaker 1: think of the universe and like atoms and protons and 63 00:03:25,960 --> 00:03:31,679 Speaker 1: electrons and rocks, asteroids, planets, all those suns, hamsters and 64 00:03:31,840 --> 00:03:36,400 Speaker 1: then the hamsters, yeah, hamsters, all that stuff out there 65 00:03:36,400 --> 00:03:39,760 Speaker 1: in the universe. Stars. That's not all there is to 66 00:03:39,840 --> 00:03:42,760 Speaker 1: it to the universe, right, A whole bunch of it 67 00:03:42,840 --> 00:03:45,560 Speaker 1: is dark energy, that's right. Yeah, most of the stuff 68 00:03:45,560 --> 00:03:47,160 Speaker 1: in the universe is not the kind of stuff that 69 00:03:47,200 --> 00:03:50,000 Speaker 1: we see around us, as you were saying, even stars 70 00:03:50,000 --> 00:03:51,840 Speaker 1: and planets and gas and dust, that all adds up 71 00:03:51,840 --> 00:03:55,680 Speaker 1: to a tiny little slipper like five turns out. And 72 00:03:55,680 --> 00:03:57,520 Speaker 1: this is the kind of stuff we've only learned recently. 73 00:03:57,760 --> 00:04:00,160 Speaker 1: Most of the universe is weird. Stuff we never even 74 00:04:00,160 --> 00:04:02,600 Speaker 1: thought about, we never even would have included in a 75 00:04:02,640 --> 00:04:05,240 Speaker 1: pie chart of the universe thirty years ago. Is the 76 00:04:05,240 --> 00:04:08,760 Speaker 1: biggest piece of the pie. It's this big kind of 77 00:04:08,800 --> 00:04:13,560 Speaker 1: mysterious energy that's out there, that's right. So imagine, for example, 78 00:04:13,600 --> 00:04:16,360 Speaker 1: you take like a cubic meter of space and you 79 00:04:16,440 --> 00:04:19,360 Speaker 1: ask what's in it. Well, on average, you average over 80 00:04:19,360 --> 00:04:21,800 Speaker 1: the whole universe that we can see, it has about 81 00:04:21,960 --> 00:04:26,039 Speaker 1: five or six hydrogen atoms worth of energy. And most 82 00:04:26,080 --> 00:04:29,400 Speaker 1: of that is not matter or or stuff that you're 83 00:04:29,400 --> 00:04:32,159 Speaker 1: familiar with. Most of it is dark energy, and another 84 00:04:32,279 --> 00:04:34,360 Speaker 1: big chunk of it is something called dark matter, which 85 00:04:34,400 --> 00:04:37,159 Speaker 1: we can talk about it in another episode. Yeah, and 86 00:04:37,160 --> 00:04:39,320 Speaker 1: and like dark energy is all around us, right, like 87 00:04:39,480 --> 00:04:42,400 Speaker 1: right now, two thirds of the room right now that 88 00:04:42,440 --> 00:04:45,919 Speaker 1: I'm in is filled with dark energy. That's right, most 89 00:04:45,920 --> 00:04:47,760 Speaker 1: of the energy in the universe and most of the 90 00:04:47,800 --> 00:04:50,680 Speaker 1: energy everywhere. And dark energy is not something that's out 91 00:04:50,680 --> 00:04:52,719 Speaker 1: there in space. You're exactly right. It's here, it's with you. 92 00:04:52,800 --> 00:04:56,760 Speaker 1: It's between your toes. It's getting refrigerator just other dark 93 00:04:56,800 --> 00:05:00,839 Speaker 1: matter between my toes. Let's be honest. I don't think 94 00:05:00,839 --> 00:05:03,240 Speaker 1: I want to know what he does, whether it's a 95 00:05:03,520 --> 00:05:06,240 Speaker 1: cosmic mystery physics or not. Yeah, let's not let's not 96 00:05:06,240 --> 00:05:10,920 Speaker 1: get into my toes on this. On this podcast, Daniel 97 00:05:11,000 --> 00:05:14,400 Speaker 1: Jorge explained the universe and Jorge's toes. That's right, that's 98 00:05:14,440 --> 00:05:16,960 Speaker 1: a winner right there. Um. But yeah, so it's a 99 00:05:17,040 --> 00:05:19,839 Speaker 1: huge deal. It's all around this and it's causing the 100 00:05:19,920 --> 00:05:23,120 Speaker 1: universe to explode. So that's that's kind of distressing. Yeah. 101 00:05:23,160 --> 00:05:25,280 Speaker 1: Not only is it turned out to be most of 102 00:05:25,320 --> 00:05:28,640 Speaker 1: the universe, it has huge consequences. Right. The universe is 103 00:05:28,680 --> 00:05:32,640 Speaker 1: exploding in every direction, and in some ways dark energy 104 00:05:32,760 --> 00:05:35,280 Speaker 1: is causing the universe to explode. Another way to think 105 00:05:35,320 --> 00:05:38,120 Speaker 1: about it is that dark energy is our description of 106 00:05:38,160 --> 00:05:40,960 Speaker 1: the fact that it is exploding. Like we saw the 107 00:05:41,040 --> 00:05:45,120 Speaker 1: universe is exploding. We named that dark energy. It's not 108 00:05:45,200 --> 00:05:48,159 Speaker 1: like there's two separate things where oh, here's dark energy, 109 00:05:48,160 --> 00:05:50,760 Speaker 1: we know that's the thing. Here's it's cause it's more 110 00:05:50,800 --> 00:05:52,720 Speaker 1: like dark energy is the description of the fact that 111 00:05:52,720 --> 00:05:55,720 Speaker 1: the universe is exploding and we don't really know why. 112 00:05:55,960 --> 00:05:58,960 Speaker 1: It's another name for the explosion of the universe. It's 113 00:05:58,960 --> 00:06:02,320 Speaker 1: a fancy tide or our lack of understanding the explosion 114 00:06:02,320 --> 00:06:04,880 Speaker 1: in the universe. It's like you don't understand something. You 115 00:06:04,960 --> 00:06:07,400 Speaker 1: have the pr version. We could have called it what 116 00:06:07,560 --> 00:06:10,479 Speaker 1: is going on with the universe? But dark energy sounds 117 00:06:10,520 --> 00:06:16,680 Speaker 1: better w two F energy your t F universe man, Yeah, exactly. 118 00:06:19,720 --> 00:06:21,880 Speaker 1: Well let's get into that. So how did how do 119 00:06:22,000 --> 00:06:24,800 Speaker 1: we find out about this dark energy that's all around 120 00:06:24,880 --> 00:06:27,240 Speaker 1: us and it's causing the universe to explode. Well, it's 121 00:06:27,279 --> 00:06:29,560 Speaker 1: one of my favorite stories in science because it's a 122 00:06:29,600 --> 00:06:32,360 Speaker 1: story where the answer was a surprise. You know, scientists 123 00:06:32,400 --> 00:06:35,159 Speaker 1: went into it asking one question and learning something totally 124 00:06:35,200 --> 00:06:38,120 Speaker 1: different about the universe. The question they started with was 125 00:06:38,600 --> 00:06:41,159 Speaker 1: what is the history of the universe and what is 126 00:06:41,200 --> 00:06:45,560 Speaker 1: the future of the universe? Like what's going to happen eventually? Yeah, exactly, 127 00:06:45,560 --> 00:06:48,920 Speaker 1: Like is this whole universe gonna keep going forever? Is 128 00:06:48,960 --> 00:06:51,520 Speaker 1: it going to compress into little dot? Do I have 129 00:06:51,680 --> 00:06:54,200 Speaker 1: time to like write that novel I've always been wanting 130 00:06:54,240 --> 00:06:56,320 Speaker 1: to write. You definitely have time to write that novel. 131 00:06:57,640 --> 00:06:59,719 Speaker 1: I have no excuse. Is it another young adult novel? 132 00:06:59,720 --> 00:07:02,679 Speaker 1: Because I have enough of those already. It's called dark 133 00:07:02,720 --> 00:07:07,880 Speaker 1: youth dark, um dark. So you've got vampires, you've got 134 00:07:07,880 --> 00:07:13,920 Speaker 1: where wolves have dark energy beings. Yeah. And so when physicists, 135 00:07:14,000 --> 00:07:16,400 Speaker 1: when physicists want to predict the future, where they typically 136 00:07:16,440 --> 00:07:18,840 Speaker 1: do is look into the past, try to understand what's 137 00:07:18,840 --> 00:07:22,000 Speaker 1: happened so far, and then extrapolate so to figure out 138 00:07:22,080 --> 00:07:24,400 Speaker 1: what the future of the universe was. They first looked 139 00:07:24,400 --> 00:07:26,880 Speaker 1: into the past and said, what's been going on so far, 140 00:07:26,920 --> 00:07:33,600 Speaker 1: and let's see what direction things are going in? Right, Like, um, uh, Like, 141 00:07:34,240 --> 00:07:36,400 Speaker 1: how am I doing financially? Do I have more money 142 00:07:36,440 --> 00:07:39,080 Speaker 1: now than I used to have money before? And that's 143 00:07:39,120 --> 00:07:40,920 Speaker 1: a that will sort of tell me, what might I 144 00:07:41,000 --> 00:07:42,880 Speaker 1: might expect in the future if I don't make ill 145 00:07:42,920 --> 00:07:45,600 Speaker 1: advised decisions. That's right. Yeah, if your net worth has 146 00:07:45,600 --> 00:07:48,160 Speaker 1: been rising, then you expected to keep going. What if 147 00:07:48,200 --> 00:07:50,640 Speaker 1: your bank account is dropping every single month, then you 148 00:07:50,640 --> 00:07:53,720 Speaker 1: can expect some sort of cataclysmic event in your near future. 149 00:07:53,800 --> 00:07:55,920 Speaker 1: And I need to record more podcasts to make more money. 150 00:07:56,160 --> 00:07:59,760 Speaker 1: That's right, that's right. And so in the physics world, 151 00:08:00,080 --> 00:08:02,000 Speaker 1: we went back to the very beginning of the universe 152 00:08:02,040 --> 00:08:04,520 Speaker 1: and said, okay, the universe started with a big bang, right, 153 00:08:04,920 --> 00:08:08,040 Speaker 1: and things blew up from there. And the question people 154 00:08:08,080 --> 00:08:11,160 Speaker 1: had in their minds was, you know, after the Big Bang, 155 00:08:11,200 --> 00:08:14,400 Speaker 1: things flying out from that huge explosion. The question was, 156 00:08:14,720 --> 00:08:17,960 Speaker 1: is there enough stuff in the universe for things to 157 00:08:18,240 --> 00:08:21,120 Speaker 1: slow down, for the gravity from that stuff to slow 158 00:08:21,280 --> 00:08:25,200 Speaker 1: things down, stop them, and then make them fall back in. 159 00:08:25,360 --> 00:08:28,160 Speaker 1: So that was one possibility people were considering that the 160 00:08:28,240 --> 00:08:31,680 Speaker 1: universe would stop, the expansion, would stop um and then 161 00:08:31,760 --> 00:08:34,480 Speaker 1: come back into a big crunch. So like the stuff 162 00:08:34,520 --> 00:08:36,679 Speaker 1: that flew out from the Big Bang, and now the 163 00:08:36,760 --> 00:08:39,319 Speaker 1: question is like, are they going to keep flying off 164 00:08:39,880 --> 00:08:42,839 Speaker 1: or maybe is there enough gravity pulling it all the 165 00:08:42,880 --> 00:08:46,880 Speaker 1: stuff together that it's gonna like slow down and then 166 00:08:47,400 --> 00:08:51,080 Speaker 1: pull back in, just kind of like how our solar 167 00:08:51,120 --> 00:08:53,839 Speaker 1: system forms. Yeah, exactly. Most of the stuff that we 168 00:08:53,960 --> 00:08:56,680 Speaker 1: know around us in the in the universe was formed 169 00:08:56,679 --> 00:08:59,640 Speaker 1: by gravity. Right, Gravity gathered together rocks and dust and 170 00:08:59,720 --> 00:09:03,320 Speaker 1: rubb and hamsters or whatever and coalesce it together. Right. 171 00:09:03,360 --> 00:09:06,200 Speaker 1: That's why the Earth is round because that's gravity's work, 172 00:09:06,400 --> 00:09:09,360 Speaker 1: tumbling everything towards a smooth surface. And that's how the 173 00:09:09,360 --> 00:09:12,640 Speaker 1: Sun is formed, its gravity compressing dust and gas until 174 00:09:12,679 --> 00:09:14,760 Speaker 1: it gets hot enough to burn. So gravity is is 175 00:09:14,880 --> 00:09:17,240 Speaker 1: very powerful force and and has a lot of time. 176 00:09:17,800 --> 00:09:20,200 Speaker 1: Um it's actually one of the weakest forces, but over 177 00:09:20,280 --> 00:09:23,000 Speaker 1: cosmic scales and all this time, it has enough power 178 00:09:23,040 --> 00:09:25,959 Speaker 1: to pull all this stuff together and compress it into objects. 179 00:09:26,000 --> 00:09:28,280 Speaker 1: So people thought, maybe that's going to happen with the 180 00:09:28,320 --> 00:09:31,800 Speaker 1: whole universe. Man, Like, maybe the whole universe is gonna 181 00:09:32,280 --> 00:09:35,280 Speaker 1: come back together and compress back into a tiny dot. 182 00:09:35,320 --> 00:09:38,240 Speaker 1: That would be pretty amazing, like a giant cloud. Does 183 00:09:38,360 --> 00:09:42,240 Speaker 1: we all just kind of come get pulled together and 184 00:09:42,320 --> 00:09:45,480 Speaker 1: we maybe come back down. That's one possible way that 185 00:09:45,520 --> 00:09:48,440 Speaker 1: the future the universe could end up. That's right. Yeah, 186 00:09:48,440 --> 00:09:51,840 Speaker 1: So option A was the big crunch. But people didn't know, 187 00:09:52,160 --> 00:09:54,480 Speaker 1: like is there enough stuff in the universe? Is there 188 00:09:54,559 --> 00:09:57,320 Speaker 1: enough gravity from that stuff to pull everything back together? 189 00:09:57,559 --> 00:10:00,200 Speaker 1: Because it could totally have been that the explore ocean 190 00:10:00,280 --> 00:10:02,960 Speaker 1: was more powerful essentially than the gravity, and the things 191 00:10:03,000 --> 00:10:06,080 Speaker 1: spread out forever. Oh, that could happen, like things that 192 00:10:06,080 --> 00:10:09,319 Speaker 1: are like a grenade out in space. It just blows 193 00:10:09,440 --> 00:10:14,120 Speaker 1: up so violently that gravity is too weak to pull 194 00:10:14,200 --> 00:10:18,040 Speaker 1: everything back together again. That's right, yeah, And that could 195 00:10:18,200 --> 00:10:19,600 Speaker 1: that could have been the fate of the universe. It 196 00:10:19,640 --> 00:10:22,439 Speaker 1: could be that the universe just keeps expanding, things spread 197 00:10:22,480 --> 00:10:25,760 Speaker 1: out and slow down like gravity. Gravity is still slowing 198 00:10:25,800 --> 00:10:28,560 Speaker 1: things down, but it doesn't have enough power to stop 199 00:10:28,600 --> 00:10:30,880 Speaker 1: it and have it fall back in. And so it 200 00:10:30,920 --> 00:10:34,000 Speaker 1: could be that just spreads out forever, getting cooler and 201 00:10:34,040 --> 00:10:37,040 Speaker 1: cooler and more distant until something we call the heat 202 00:10:37,200 --> 00:10:40,760 Speaker 1: death of the universe. That's when everything is the same temperature. Right, 203 00:10:40,800 --> 00:10:43,160 Speaker 1: So physicists were like, are we ever going to be cool? 204 00:10:44,120 --> 00:10:49,520 Speaker 1: That was a front question. We'll know in about to 205 00:10:49,559 --> 00:10:52,559 Speaker 1: find out if physicists are ever cool. So that's I mean, 206 00:10:52,559 --> 00:10:55,320 Speaker 1: that is a very significant question, right, Like we're we 207 00:10:55,400 --> 00:10:57,360 Speaker 1: live in this universe. We kind of want to know, 208 00:10:57,520 --> 00:11:00,320 Speaker 1: like where is this whole thing headed? Yeah, I wonder 209 00:11:00,400 --> 00:11:03,680 Speaker 1: if it's interesting to most people. To me, as a physicist, 210 00:11:03,760 --> 00:11:05,920 Speaker 1: I think it's one of the most interesting questions, Like 211 00:11:06,040 --> 00:11:09,319 Speaker 1: what is the future of this whole amazing, beautiful experiment 212 00:11:09,360 --> 00:11:11,360 Speaker 1: we're living in, you know, is it going to go 213 00:11:11,400 --> 00:11:13,599 Speaker 1: on forever? Is it going to tear uself apart? Is 214 00:11:13,600 --> 00:11:16,440 Speaker 1: it going to crunch together? Like? To me, that's a 215 00:11:16,480 --> 00:11:19,120 Speaker 1: really interesting question, Like do we live at the peak 216 00:11:19,120 --> 00:11:21,280 Speaker 1: of it? Or are we like in the after party, 217 00:11:21,480 --> 00:11:23,560 Speaker 1: you know what I mean? Like, or are we or 218 00:11:23,600 --> 00:11:25,760 Speaker 1: are our great grandchildren going to be like at the 219 00:11:25,800 --> 00:11:28,280 Speaker 1: peak of the universe? Yeah? I think I think that's 220 00:11:28,280 --> 00:11:30,920 Speaker 1: exactly right. And I think there's an issue of context there, right, 221 00:11:30,960 --> 00:11:33,640 Speaker 1: Like as humans, we are always striving to understand the 222 00:11:33,720 --> 00:11:37,040 Speaker 1: context of our existence. Why is this important? What's going on? 223 00:11:37,559 --> 00:11:40,280 Speaker 1: And one of those questions is like is Earth at 224 00:11:40,320 --> 00:11:43,120 Speaker 1: the center of the cosmos? Is Earth even important? And 225 00:11:43,160 --> 00:11:45,760 Speaker 1: another question is like that but in time? Right, like 226 00:11:45,880 --> 00:11:49,040 Speaker 1: are we living at an important time? What is the 227 00:11:49,120 --> 00:11:52,040 Speaker 1: future going to be? Like where do we fit in? Yeah? 228 00:11:52,280 --> 00:11:54,040 Speaker 1: Are people in a billion years going to look back 229 00:11:54,040 --> 00:11:56,280 Speaker 1: and say, man, I wish I'd lived when Daniel L. Jorge, 230 00:11:56,280 --> 00:11:58,960 Speaker 1: we're doing. They're awesome podcasts because those were the days, 231 00:11:59,080 --> 00:12:01,880 Speaker 1: many the good old days of the universe. Yeah, this 232 00:12:01,920 --> 00:12:07,600 Speaker 1: podcast is peak civilization, right, podcast is peak civilization. So 233 00:12:07,720 --> 00:12:21,720 Speaker 1: state tuned state that one. Let's take a quick break. Yeah. 234 00:12:21,760 --> 00:12:24,080 Speaker 1: So people were thinking about those two options, right, big 235 00:12:24,120 --> 00:12:28,240 Speaker 1: crunch or heat death of the universe. So option A 236 00:12:28,520 --> 00:12:32,520 Speaker 1: everything comes crashing back down. Option B things just gonna 237 00:12:32,559 --> 00:12:35,920 Speaker 1: float away, yeah, exactly. And so what they wanted to 238 00:12:35,960 --> 00:12:38,040 Speaker 1: do was look back in time because you can't actually 239 00:12:38,120 --> 00:12:40,800 Speaker 1: see the future, but it's not that hard in physics 240 00:12:40,800 --> 00:12:43,600 Speaker 1: to see the past, especially in astronomy. To see the past, 241 00:12:43,679 --> 00:12:45,600 Speaker 1: all you have to do is look out into space, 242 00:12:46,040 --> 00:12:49,040 Speaker 1: and everything you see in space happened in the past, 243 00:12:49,559 --> 00:12:52,520 Speaker 1: just because it takes light time to get here from there. 244 00:12:52,679 --> 00:12:54,480 Speaker 1: It's like back in the day when there was no 245 00:12:54,640 --> 00:12:58,880 Speaker 1: email or internet, you would get your news from mail letters, right, 246 00:12:59,080 --> 00:13:04,319 Speaker 1: And so the further away what did actually happened? At 247 00:13:04,360 --> 00:13:08,400 Speaker 1: some point the internet did not exist, Daniel, what what what? 248 00:13:08,880 --> 00:13:14,000 Speaker 1: It was all dark dark mail? Ye, dark mail. So yeah, 249 00:13:14,000 --> 00:13:16,280 Speaker 1: so like the further away you get a letter the 250 00:13:16,360 --> 00:13:20,240 Speaker 1: older that news was, yes, exactly. And some people think, oh, 251 00:13:20,240 --> 00:13:22,480 Speaker 1: that's a bummer. I think it's actually pretty cool because 252 00:13:22,480 --> 00:13:24,600 Speaker 1: it lets us look into the past, and so the 253 00:13:24,679 --> 00:13:26,720 Speaker 1: further out you look, the further in the back in 254 00:13:26,720 --> 00:13:28,400 Speaker 1: the past you can see. And the goal is to see, 255 00:13:28,440 --> 00:13:31,920 Speaker 1: like how fast is stuff moving away from us, you know, 256 00:13:31,960 --> 00:13:34,240 Speaker 1: the expansion of the universe. How fast is stuff moving 257 00:13:34,240 --> 00:13:36,440 Speaker 1: away from us now? And how fast was it moving 258 00:13:36,440 --> 00:13:39,440 Speaker 1: away from us earlier? So we could understand like, how 259 00:13:39,520 --> 00:13:41,280 Speaker 1: is this changing, what is the faith going to be? 260 00:13:41,360 --> 00:13:45,080 Speaker 1: Is its slowing down? How fast is it slowing down? Yeah, So, 261 00:13:45,120 --> 00:13:47,000 Speaker 1: because like if the fate of the universe was for 262 00:13:47,080 --> 00:13:50,400 Speaker 1: it to crunch down, then you would see things kind 263 00:13:50,440 --> 00:13:54,080 Speaker 1: of expanding slower now than before. Like before you think 264 00:13:54,120 --> 00:13:56,280 Speaker 1: this would be flying out, and now they would be 265 00:13:56,320 --> 00:13:58,920 Speaker 1: kind of slowing down, And so we could expect things 266 00:13:58,920 --> 00:14:03,000 Speaker 1: to crunch or if we measure things to be moving 267 00:14:03,000 --> 00:14:05,600 Speaker 1: at about the same now as as they were before, 268 00:14:05,760 --> 00:14:07,720 Speaker 1: then maybe the fate of the universe is just to 269 00:14:07,760 --> 00:14:11,120 Speaker 1: kind of keep floating off and getting cooler exactly. And 270 00:14:11,160 --> 00:14:13,040 Speaker 1: so that was the question. They were like, let's look 271 00:14:13,080 --> 00:14:15,439 Speaker 1: and see how things are changing. How much is it 272 00:14:15,520 --> 00:14:18,080 Speaker 1: slowing down? Is slowing down a lot, which means maybe 273 00:14:18,120 --> 00:14:20,440 Speaker 1: big crunch are slowing down just a little, which means 274 00:14:20,480 --> 00:14:23,120 Speaker 1: maybe heat death. That was the question they asked. But 275 00:14:23,120 --> 00:14:26,600 Speaker 1: it's actually fascinating how they did it because it's tricky, right. 276 00:14:26,640 --> 00:14:29,160 Speaker 1: In order to know how far back in the past 277 00:14:29,200 --> 00:14:31,360 Speaker 1: you're looking, you have to know how far away a 278 00:14:31,440 --> 00:14:34,640 Speaker 1: star is. And that's not easy to figure out, right, 279 00:14:34,720 --> 00:14:38,200 Speaker 1: because like, if you look at a star, it's um, 280 00:14:38,240 --> 00:14:39,920 Speaker 1: if it's dim, you don't know if it's just like 281 00:14:39,960 --> 00:14:42,040 Speaker 1: a weak star or a really far away star. It's 282 00:14:42,040 --> 00:14:45,120 Speaker 1: just a little point, right, it's hard to tell. You can't, like, um, 283 00:14:45,680 --> 00:14:47,640 Speaker 1: tell how far away it is just from how bright 284 00:14:47,680 --> 00:14:49,880 Speaker 1: that point is. That's right. You can't tell the difference 285 00:14:49,880 --> 00:14:52,760 Speaker 1: between a star that's very bright and far away and 286 00:14:52,880 --> 00:14:55,960 Speaker 1: very weak and close up. Um. We have some tricks, 287 00:14:56,160 --> 00:14:59,160 Speaker 1: but none of them are really good. Um. The early days, 288 00:14:59,680 --> 00:15:01,960 Speaker 1: UM people used to figure out how far away stars 289 00:15:01,960 --> 00:15:04,400 Speaker 1: were by seeing how they shifted as their Earth went 290 00:15:04,440 --> 00:15:07,440 Speaker 1: around the sun. Because if something was really close, then 291 00:15:07,480 --> 00:15:09,600 Speaker 1: you could see it sliding back and forth as the 292 00:15:09,640 --> 00:15:12,080 Speaker 1: Earth went around the Sun. That's called the parallax system. 293 00:15:12,120 --> 00:15:14,520 Speaker 1: It's like how you triangulate with your eyes, right, like 294 00:15:14,560 --> 00:15:17,320 Speaker 1: if yes, if something looks really different when you wink 295 00:15:17,400 --> 00:15:19,200 Speaker 1: one eye and you wink the other one, then it 296 00:15:19,280 --> 00:15:22,040 Speaker 1: must be pretty close. But if it doesn't change a 297 00:15:22,040 --> 00:15:26,280 Speaker 1: lot when you wink between eyes, then uh, it's far away. Yeah, 298 00:15:26,360 --> 00:15:28,400 Speaker 1: And so that's the original way people can figure out 299 00:15:28,440 --> 00:15:30,440 Speaker 1: how far stuff away is. And then it was like 300 00:15:30,480 --> 00:15:33,240 Speaker 1: in the nineteen twenties when Hubble figured out a new 301 00:15:33,240 --> 00:15:35,560 Speaker 1: way to look at stuff in the sky and he 302 00:15:35,600 --> 00:15:39,000 Speaker 1: found a particular kind of star called a seafid that 303 00:15:39,200 --> 00:15:42,480 Speaker 1: rotated and its brightness was connected to how fast it 304 00:15:42,560 --> 00:15:45,000 Speaker 1: was rotating, so you could figure out by measuring its 305 00:15:45,080 --> 00:15:47,360 Speaker 1: rotation how bright it is, which told you how far 306 00:15:47,400 --> 00:15:49,440 Speaker 1: away it was. So he was the first one to 307 00:15:49,440 --> 00:15:51,720 Speaker 1: be able to see things that were further away. And 308 00:15:51,760 --> 00:15:54,200 Speaker 1: he's actually the one who figured out not just that 309 00:15:54,240 --> 00:15:57,600 Speaker 1: the universe is expanding. Before that, people thought, oh, the 310 00:15:57,680 --> 00:15:59,960 Speaker 1: universe is just a bunch of stars hanging in space 311 00:16:00,000 --> 00:16:03,120 Speaker 1: ace And he figured out two amazing things. One is 312 00:16:03,440 --> 00:16:06,320 Speaker 1: the universe is expanding, and the other is that the 313 00:16:06,400 --> 00:16:09,400 Speaker 1: universe is more than just our galaxy. And what do 314 00:16:09,480 --> 00:16:12,360 Speaker 1: you mean more? He figured out that there were other galaxies. 315 00:16:12,720 --> 00:16:16,560 Speaker 1: That's right, before Hubble, we thought there is just our galaxy, Like, 316 00:16:16,640 --> 00:16:20,600 Speaker 1: imagine just a single galaxy floating in space. That's what 317 00:16:20,680 --> 00:16:24,240 Speaker 1: people thought the universe was. He saw these little smudges 318 00:16:24,320 --> 00:16:26,080 Speaker 1: up in the sky that people thought, oh, these should 319 00:16:26,120 --> 00:16:28,840 Speaker 1: just dust or clouds or something turns, and that he 320 00:16:29,000 --> 00:16:32,040 Speaker 1: proved by measuring the distance to them, that they were 321 00:16:32,160 --> 00:16:34,440 Speaker 1: way too far away to be part of our galaxy. 322 00:16:34,640 --> 00:16:37,720 Speaker 1: He proved that they were actually other galaxies, and that 323 00:16:37,800 --> 00:16:40,400 Speaker 1: those galaxies who were running away from us. It must 324 00:16:40,440 --> 00:16:42,600 Speaker 1: have been so mind blowing to be Hubble, you know, 325 00:16:42,640 --> 00:16:45,800 Speaker 1: to have this moment of realization, Uh, to understand this 326 00:16:46,040 --> 00:16:49,680 Speaker 1: huge context of our of our existence. Yeah, it must 327 00:16:49,680 --> 00:16:54,840 Speaker 1: be very humble to be Hubble. You know, I don't 328 00:16:54,840 --> 00:16:57,280 Speaker 1: know anything about Hubble, but a lot of these famous 329 00:16:57,280 --> 00:17:01,520 Speaker 1: physicists were not the nicest guys. So is that you 330 00:17:01,720 --> 00:17:04,480 Speaker 1: are their stories about Hubble. I don't know any of them, 331 00:17:04,680 --> 00:17:07,320 Speaker 1: but if I had to guess any random famous physicist 332 00:17:07,359 --> 00:17:10,359 Speaker 1: from history, they probably got there by not being the 333 00:17:10,440 --> 00:17:13,880 Speaker 1: nicest of a person. Yeah, humble. Anyway, Hubble was able 334 00:17:13,920 --> 00:17:16,960 Speaker 1: to see past our galaxy, but cosmically speaking, that's not 335 00:17:17,000 --> 00:17:18,679 Speaker 1: far enough to be able to tell because that's just 336 00:17:18,720 --> 00:17:21,280 Speaker 1: like the last you know, a little bit of the history. 337 00:17:21,600 --> 00:17:24,080 Speaker 1: Then it was in the nineties nineties, people developed a 338 00:17:24,160 --> 00:17:26,919 Speaker 1: powerful new technique that let them see much further, so 339 00:17:27,000 --> 00:17:29,360 Speaker 1: we could tell how far away things were that were 340 00:17:29,480 --> 00:17:31,840 Speaker 1: much much, much further, and that gave us a much 341 00:17:31,920 --> 00:17:36,280 Speaker 1: deeper view, further than like the nearest galaxy, yeah, really 342 00:17:36,280 --> 00:17:39,320 Speaker 1: far away galaxies. And that's a new kind of star 343 00:17:39,520 --> 00:17:43,400 Speaker 1: that we started to understand, called a type one, a supernova. Right, 344 00:17:43,520 --> 00:17:46,560 Speaker 1: they call him like the standard candles, right, exactly the 345 00:17:46,680 --> 00:17:49,320 Speaker 1: standard candles because they act the same way everywhere in 346 00:17:49,320 --> 00:17:51,440 Speaker 1: the universe. And so we can tell we know how 347 00:17:51,440 --> 00:17:54,160 Speaker 1: bright they are, so based on how dim they are 348 00:17:54,320 --> 00:17:56,480 Speaker 1: or how bright, we can tell how far away they are. 349 00:17:57,080 --> 00:18:00,400 Speaker 1: So it was in the nineties people figured this thing out, like, look, 350 00:18:00,400 --> 00:18:02,880 Speaker 1: we have a new standard candle that let's look much 351 00:18:02,960 --> 00:18:05,320 Speaker 1: deeper into the history of the universe and how we 352 00:18:05,359 --> 00:18:07,680 Speaker 1: can answer this question. We can figure out what is 353 00:18:07,720 --> 00:18:09,680 Speaker 1: the future of the universe, What is it going to be? 354 00:18:09,840 --> 00:18:12,359 Speaker 1: So most stars are you can't really tell, right, some 355 00:18:12,400 --> 00:18:14,399 Speaker 1: of them are dim, some of them are far away. 356 00:18:14,480 --> 00:18:17,720 Speaker 1: But there are this special type of star. It always 357 00:18:17,720 --> 00:18:21,280 Speaker 1: explodes the same way, so that if you see it 358 00:18:21,920 --> 00:18:23,800 Speaker 1: m really bright and must be closed, or if you 359 00:18:23,840 --> 00:18:25,960 Speaker 1: see it really dim, it must be far away, right, 360 00:18:26,040 --> 00:18:27,800 Speaker 1: that's right. And these are not just stars, as you said, 361 00:18:27,840 --> 00:18:30,919 Speaker 1: these are supernova, right, they're the end of stars. Right. 362 00:18:30,960 --> 00:18:35,040 Speaker 1: That's when stars collapse and implode, followed by huge, enormous 363 00:18:35,119 --> 00:18:38,919 Speaker 1: cosmic explosion. And that explosion is super bright, like a 364 00:18:38,960 --> 00:18:43,000 Speaker 1: single supernova can outshine the entire galaxy it's in, but 365 00:18:43,080 --> 00:18:45,520 Speaker 1: just for a few days. It's like crazily burning up 366 00:18:45,560 --> 00:18:47,480 Speaker 1: all of its fuel. It's like a flare. If you 367 00:18:47,520 --> 00:18:50,200 Speaker 1: set your house on fire, it's brighter than the whole neighborhood, right, 368 00:18:50,040 --> 00:18:53,560 Speaker 1: but not very long. So there were you know, people 369 00:18:53,560 --> 00:18:56,240 Speaker 1: figure this out, and then people um sort of split 370 00:18:56,280 --> 00:18:58,159 Speaker 1: into two teams. It was a team at Berkeley and 371 00:18:58,160 --> 00:19:00,480 Speaker 1: there was a team in Australia, and and they were 372 00:19:00,600 --> 00:19:03,560 Speaker 1: racing to discover to get as much data as possible 373 00:19:03,760 --> 00:19:06,560 Speaker 1: because supernova are not regular. It's not like you know 374 00:19:06,600 --> 00:19:08,359 Speaker 1: when it's going to happen. You have to just scan 375 00:19:08,520 --> 00:19:10,560 Speaker 1: the sky and hope to see one. Then it developed 376 00:19:10,560 --> 00:19:13,359 Speaker 1: special technology to look through all this telescope data and 377 00:19:13,359 --> 00:19:16,000 Speaker 1: try to find new stars that were appearing in the sky, 378 00:19:16,000 --> 00:19:18,000 Speaker 1: because that's what a supernova looks like, looks like a 379 00:19:18,040 --> 00:19:20,520 Speaker 1: bright new star that appears and then it fades over 380 00:19:20,560 --> 00:19:22,880 Speaker 1: a matter of days, and if you capture enough data 381 00:19:22,880 --> 00:19:25,080 Speaker 1: about it, then you can learn about its brightness and 382 00:19:25,080 --> 00:19:27,400 Speaker 1: figure out how far away it was. And so finally 383 00:19:27,560 --> 00:19:31,200 Speaker 1: one of them discovered, like, hey, we have a measurement 384 00:19:31,359 --> 00:19:35,760 Speaker 1: for how the universe is expanding, whether it's expanding faster 385 00:19:35,920 --> 00:19:38,320 Speaker 1: or slower than before. Yeah, it took a took a 386 00:19:38,320 --> 00:19:40,399 Speaker 1: couple of years for them to have enough data, and 387 00:19:40,400 --> 00:19:42,320 Speaker 1: it was a scramble and think, I think those people 388 00:19:42,359 --> 00:19:44,560 Speaker 1: must have been working twenty hour days in the seven 389 00:19:44,640 --> 00:19:47,119 Speaker 1: days a week. Yeah, everyone wanted to be the first 390 00:19:47,160 --> 00:19:50,480 Speaker 1: to say like, hey, here's that measurement exactly. Finally they 391 00:19:50,520 --> 00:19:53,760 Speaker 1: had this plot of how fast the universe is expanding 392 00:19:53,960 --> 00:19:57,000 Speaker 1: as a function of time. And what they discovered is 393 00:19:57,040 --> 00:20:00,000 Speaker 1: that the universe is not slowing down a lot or 394 00:20:00,040 --> 00:20:02,720 Speaker 1: slowing down a little. So it's not option A nor 395 00:20:02,760 --> 00:20:06,600 Speaker 1: option B. That's right. The universe went for secret options. 396 00:20:06,680 --> 00:20:09,320 Speaker 1: See secret Ope, you didn't even know it was on 397 00:20:09,359 --> 00:20:11,520 Speaker 1: the menu. And that's what we got for dinner, right. 398 00:20:12,160 --> 00:20:14,480 Speaker 1: And I love when the universe does that because it's like, oh, 399 00:20:14,520 --> 00:20:17,000 Speaker 1: you silly little humans, you have no idea what even 400 00:20:17,119 --> 00:20:20,120 Speaker 1: question you're asking? Right? You hadn't even thought about this answer. 401 00:20:20,320 --> 00:20:22,680 Speaker 1: That's right, and so secret options see is that the universe, 402 00:20:22,880 --> 00:20:25,119 Speaker 1: the expansion of the universe is not slowing down at all. 403 00:20:25,240 --> 00:20:29,199 Speaker 1: It's increasing. It's getting faster and faster, it's accelerating. So 404 00:20:29,280 --> 00:20:31,399 Speaker 1: the fate of the universe is not that it's going 405 00:20:31,440 --> 00:20:33,760 Speaker 1: to crunch down or just float away. Things are like 406 00:20:35,160 --> 00:20:38,119 Speaker 1: phraising away from each other, that's right, Faster and faster 407 00:20:38,280 --> 00:20:41,119 Speaker 1: every year. Something out there, we don't know what it is. 408 00:20:41,280 --> 00:20:43,040 Speaker 1: We can't explain it, we don't understand it at all. 409 00:20:43,560 --> 00:20:46,160 Speaker 1: Something out there is pushing all of these other galaxies 410 00:20:46,200 --> 00:20:48,200 Speaker 1: away from us, and it's doing it faster and faster 411 00:20:48,320 --> 00:20:50,879 Speaker 1: every year. Like if you you only need to know 412 00:20:50,920 --> 00:20:53,479 Speaker 1: a little bit of physics to know that accelerating an 413 00:20:53,640 --> 00:20:57,080 Speaker 1: entire galaxy hundreds of billions of stars, takes a huge 414 00:20:57,080 --> 00:20:59,800 Speaker 1: amount of energy. That's why we were talking earlier about 415 00:20:59,800 --> 00:21:02,320 Speaker 1: how two thirds of the energy in the universe, because 416 00:21:02,359 --> 00:21:05,160 Speaker 1: it's not a small feat to expand the whole universe 417 00:21:05,240 --> 00:21:08,600 Speaker 1: faster every year. Yeah, it's like these galaxies want to 418 00:21:08,600 --> 00:21:10,920 Speaker 1: get together because of gravity, either pulling on each other 419 00:21:11,080 --> 00:21:14,639 Speaker 1: to get closer, but something is actually pushing them apart. 420 00:21:14,760 --> 00:21:17,560 Speaker 1: That's right, and that's the thing we call dark energy. 421 00:21:17,600 --> 00:21:21,000 Speaker 1: So they discover this thing, total mind blow, like what 422 00:21:21,160 --> 00:21:23,679 Speaker 1: the universe is totally different from what we thought it was. 423 00:21:23,920 --> 00:21:25,760 Speaker 1: The fad of the universe is different from what we 424 00:21:25,840 --> 00:21:28,719 Speaker 1: possibly imagined. Then there's this second big question, which is 425 00:21:28,920 --> 00:21:32,080 Speaker 1: what is it? Right, we found it. We we know 426 00:21:32,160 --> 00:21:34,119 Speaker 1: that it's there, we see that it's happening, but we 427 00:21:34,119 --> 00:21:36,919 Speaker 1: don't understand it at all. We just observe it. Okay, 428 00:21:36,920 --> 00:21:39,440 Speaker 1: but before we get into that, let's take a quick break. 429 00:21:50,000 --> 00:21:53,080 Speaker 1: That's what dark energy is. It's like that thing that 430 00:21:53,240 --> 00:21:57,040 Speaker 1: is pushing all the galaxies apart. That's right, the totally unexplained, 431 00:21:57,440 --> 00:22:01,200 Speaker 1: ununderstood phenomena which is shredding the universe and causing it 432 00:22:01,240 --> 00:22:04,560 Speaker 1: to explode and changing its future. That's what dark energy is. 433 00:22:04,760 --> 00:22:07,040 Speaker 1: And most people walking in the street have no idea. 434 00:22:07,240 --> 00:22:11,399 Speaker 1: It's like the phenomenon of the universe expanding faster and faster. 435 00:22:11,600 --> 00:22:14,240 Speaker 1: That's dark energy. That's exactly right, like some kind of 436 00:22:14,280 --> 00:22:17,760 Speaker 1: like actual like energy like a photon or some kind 437 00:22:17,800 --> 00:22:20,479 Speaker 1: of like thing like we really don't know what it is. 438 00:22:20,640 --> 00:22:23,240 Speaker 1: All we know is that it's energy. That's all we know. 439 00:22:24,040 --> 00:22:26,919 Speaker 1: Um And we know that it's accelerating the universe. And 440 00:22:26,920 --> 00:22:30,199 Speaker 1: it fascinating thing is that it's not just pushing stuff 441 00:22:30,320 --> 00:22:33,760 Speaker 1: through space. Right. One way to imagine a galaxy moving 442 00:22:33,760 --> 00:22:36,119 Speaker 1: away from you is that it's moving through space away 443 00:22:36,160 --> 00:22:38,360 Speaker 1: from you, right, And that's what you imagine probably when 444 00:22:38,359 --> 00:22:40,480 Speaker 1: you think of the Big Bang. Everything comes out of 445 00:22:40,480 --> 00:22:43,640 Speaker 1: this tiny little ball and expands through space. But dark 446 00:22:43,760 --> 00:22:48,040 Speaker 1: energy is doing something else. It's also creating new space 447 00:22:48,119 --> 00:22:50,719 Speaker 1: between us and the other galaxies. It's not just pushing 448 00:22:50,720 --> 00:22:54,560 Speaker 1: things through space. It's making new empty space. It's not 449 00:22:54,600 --> 00:22:57,119 Speaker 1: pushing you and meet apart from each other. It's like 450 00:22:57,200 --> 00:23:02,400 Speaker 1: it's creating more uh room, more more land in between 451 00:23:02,440 --> 00:23:04,800 Speaker 1: in between us. That's right. It's making the four or 452 00:23:04,880 --> 00:23:08,159 Speaker 1: five even longer. Well you know what I mean, like 453 00:23:08,200 --> 00:23:10,959 Speaker 1: a like a tectonic plading now, like it comes up 454 00:23:11,000 --> 00:23:14,120 Speaker 1: and it creates land and it pushes things apart. That's 455 00:23:14,160 --> 00:23:17,720 Speaker 1: kind of what dark energy is doing out in space, Yes, 456 00:23:17,760 --> 00:23:20,879 Speaker 1: exactly right, creating new real estate in between you and me. 457 00:23:21,200 --> 00:23:24,199 Speaker 1: That's pushing me apart, further apart from you, that's right. 458 00:23:24,240 --> 00:23:26,600 Speaker 1: And it's hard to think about what it means new space. 459 00:23:26,640 --> 00:23:28,800 Speaker 1: What is that unless you think about space in a 460 00:23:28,800 --> 00:23:31,520 Speaker 1: different way spaces and just emptiness or nothingness. As we've 461 00:23:31,520 --> 00:23:34,280 Speaker 1: said on this podcast a few times, it's this dynamic 462 00:23:34,320 --> 00:23:36,720 Speaker 1: physical thing. And this is one reason we think it's 463 00:23:36,760 --> 00:23:38,520 Speaker 1: more than just emptiness, is that it can do this 464 00:23:38,600 --> 00:23:41,680 Speaker 1: thing that emptiness can't, which is create more of itself. 465 00:23:42,440 --> 00:23:45,720 Speaker 1: It's not nothing. It's like real estate, and there's more 466 00:23:45,760 --> 00:23:48,720 Speaker 1: of it being created. That's right. Location, location, location, you know, 467 00:23:48,720 --> 00:23:51,320 Speaker 1: it's the most important thing. Right And new space is 468 00:23:51,320 --> 00:23:54,160 Speaker 1: being created all the time, and that's what dark energy 469 00:23:54,200 --> 00:23:56,240 Speaker 1: is doing, is creating this new space. And we don't 470 00:23:56,240 --> 00:23:58,440 Speaker 1: have any explanation for it. You know, people think about 471 00:23:58,520 --> 00:24:00,560 Speaker 1: theories of what is dark energy? You could it be this? 472 00:24:00,640 --> 00:24:03,840 Speaker 1: Could it be that. One idea that physicists like is 473 00:24:03,880 --> 00:24:06,040 Speaker 1: to think about the energy of this empty space, like 474 00:24:06,080 --> 00:24:10,480 Speaker 1: maybe space itself has energy. Maybe space can never really 475 00:24:10,520 --> 00:24:12,760 Speaker 1: be empty. You know, it's full of the Higgs field, 476 00:24:12,800 --> 00:24:14,800 Speaker 1: and it's full of virtual particles, and it's full of 477 00:24:14,840 --> 00:24:17,760 Speaker 1: all this little quantum frothing bubblinus. Right Like by its 478 00:24:17,880 --> 00:24:21,080 Speaker 1: very nature is just like this has a bubbly personality. 479 00:24:21,760 --> 00:24:26,400 Speaker 1: That's right. Space is friendly. It wants to have more 480 00:24:26,440 --> 00:24:28,760 Speaker 1: of itself. It's social and so one idea is maybe 481 00:24:28,840 --> 00:24:32,199 Speaker 1: dark energy is this energy of empty space. Problem is, 482 00:24:32,200 --> 00:24:34,120 Speaker 1: if you sit down to do the calculations, you say, 483 00:24:34,200 --> 00:24:36,080 Speaker 1: all right, well, let's calculate how much energy there is 484 00:24:36,080 --> 00:24:38,280 Speaker 1: an empty space, and compared to what we see, you 485 00:24:38,320 --> 00:24:40,720 Speaker 1: come up with a number that's way off, like not 486 00:24:40,840 --> 00:24:43,760 Speaker 1: a little bit off off by ten to the sixty 487 00:24:43,840 --> 00:24:47,760 Speaker 1: and let's ten with sixty zeros beyond its error. It's 488 00:24:47,760 --> 00:24:51,199 Speaker 1: a pretty big mistake. So the other fascinating thing is 489 00:24:51,200 --> 00:24:53,600 Speaker 1: that it hasn't been doing it forever. It turned on 490 00:24:53,640 --> 00:24:57,840 Speaker 1: about five billion years ago and started this acceleration. And 491 00:24:57,880 --> 00:25:00,600 Speaker 1: again we don't know why. We don't know what turns 492 00:25:00,600 --> 00:25:02,520 Speaker 1: it on. We know what we turn it off. You 493 00:25:02,560 --> 00:25:05,000 Speaker 1: know what is dark energy? Like you know long walks 494 00:25:05,040 --> 00:25:06,919 Speaker 1: on the beach. I don't know. We don't know very 495 00:25:07,000 --> 00:25:09,280 Speaker 1: much about it. It wasn't always there from the beginning 496 00:25:09,280 --> 00:25:11,920 Speaker 1: of the Big Bang. It's just some somehow five billion 497 00:25:12,000 --> 00:25:16,240 Speaker 1: years ago it started pushing things more actively. Yeah, these days, 498 00:25:16,280 --> 00:25:19,399 Speaker 1: the most modern picture of cosmology, I think, considers the 499 00:25:19,440 --> 00:25:22,000 Speaker 1: Big Bang and dark energy to be sort of connected. Like, 500 00:25:22,080 --> 00:25:24,960 Speaker 1: imagine a huge expansion of the universe in the very 501 00:25:25,000 --> 00:25:27,280 Speaker 1: first few moments that we called the Big Bang or 502 00:25:27,320 --> 00:25:29,800 Speaker 1: these days we call that inflation. And then that stopped 503 00:25:29,880 --> 00:25:32,000 Speaker 1: and things just sort of floated through space for a while, 504 00:25:32,200 --> 00:25:35,119 Speaker 1: and then five billion years ago it started again. So 505 00:25:35,240 --> 00:25:37,040 Speaker 1: one sense you could think of dark energy is like 506 00:25:37,440 --> 00:25:40,879 Speaker 1: phase two of the Big Bang. The Big Bang continued, 507 00:25:41,040 --> 00:25:42,840 Speaker 1: you know, but just when you thought it was safe 508 00:25:42,840 --> 00:25:45,520 Speaker 1: to get into space, here comes the dark energy, Here 509 00:25:45,560 --> 00:25:49,080 Speaker 1: comes the Bigger Bang. Yeah, both of them are expansions 510 00:25:49,080 --> 00:25:51,880 Speaker 1: of space. We think they're probably related, but we don't 511 00:25:52,000 --> 00:25:54,760 Speaker 1: really know how or why you cannot do the same thing. 512 00:25:54,840 --> 00:25:57,160 Speaker 1: But who knows why would take a nap for five 513 00:25:57,160 --> 00:26:00,359 Speaker 1: billion years? That's right, I'm sorry what you do and 514 00:26:01,080 --> 00:26:04,399 Speaker 1: the time are we getting build for that time? Yeah, exactly. 515 00:26:04,840 --> 00:26:06,880 Speaker 1: And there are big consequences for the fact that it's 516 00:26:06,920 --> 00:26:10,440 Speaker 1: not just pushing things through space but actually creating new space. Yeah, 517 00:26:10,440 --> 00:26:13,639 Speaker 1: because we started a podcast asking like what's going to 518 00:26:13,720 --> 00:26:16,439 Speaker 1: happen to the universe at the end, and so it 519 00:26:16,480 --> 00:26:19,040 Speaker 1: has you say, it has big consequences for like what's 520 00:26:19,040 --> 00:26:22,520 Speaker 1: going to happen to the universe. Yeah, because it's creating 521 00:26:22,560 --> 00:26:26,480 Speaker 1: new space, which means it's effectively evading the speed limit 522 00:26:26,520 --> 00:26:29,040 Speaker 1: of the universe, the speed of light. Right, nothing in 523 00:26:29,080 --> 00:26:31,840 Speaker 1: the universe can move through space faster than the speed 524 00:26:31,880 --> 00:26:33,680 Speaker 1: of light. All right, that's a hard and fast limit. 525 00:26:34,320 --> 00:26:37,320 Speaker 1: And so these galaxies can't move through space away from 526 00:26:37,359 --> 00:26:40,880 Speaker 1: us faster than the speed of light. But there's no 527 00:26:41,000 --> 00:26:44,920 Speaker 1: limit on how fast you can create new space, the 528 00:26:45,119 --> 00:26:48,280 Speaker 1: new spaces being created between us and these other galaxies 529 00:26:48,640 --> 00:26:51,159 Speaker 1: faster than light can go through it. It's like if 530 00:26:51,200 --> 00:26:54,280 Speaker 1: I was trying to get to you done at Irvine U, 531 00:26:54,400 --> 00:26:56,040 Speaker 1: and I can only go seventy miles per hour in 532 00:26:56,080 --> 00:26:59,399 Speaker 1: the highway. You know, nominally you'd be lucky to do that. 533 00:27:01,200 --> 00:27:03,359 Speaker 1: Let's say it's like two am and have your private 534 00:27:05,920 --> 00:27:07,919 Speaker 1: Let's say I was using the carpool lane, all right, 535 00:27:08,000 --> 00:27:10,480 Speaker 1: and uh but yeah, but like let's say that a 536 00:27:10,600 --> 00:27:13,040 Speaker 1: new land was being created between you and me faster 537 00:27:13,119 --> 00:27:15,199 Speaker 1: than seventy miles per hour, I would never get to you. 538 00:27:15,320 --> 00:27:17,640 Speaker 1: That's right. If they're just laying new road and you're 539 00:27:18,080 --> 00:27:20,280 Speaker 1: faster than you're driving through it, you'll never get down 540 00:27:20,280 --> 00:27:24,080 Speaker 1: to Irvine, exactly right. And that's the situation. Those photons 541 00:27:24,119 --> 00:27:27,280 Speaker 1: that are leaving those galaxies now will never reach us 542 00:27:27,640 --> 00:27:30,359 Speaker 1: because the space in between us is growing faster and 543 00:27:30,400 --> 00:27:32,480 Speaker 1: the photons go through it right at some point they'll 544 00:27:32,520 --> 00:27:35,280 Speaker 1: stop reaching us, right like um like, we'll see them, 545 00:27:35,280 --> 00:27:39,600 Speaker 1: and then suddenly they'll blink out of existence. Exactly things 546 00:27:39,640 --> 00:27:42,040 Speaker 1: that used to be in our observable universe, things that 547 00:27:42,080 --> 00:27:44,440 Speaker 1: we see now because light has had a chance to 548 00:27:44,480 --> 00:27:47,280 Speaker 1: get through the universe to us, will no longer be 549 00:27:47,320 --> 00:27:50,760 Speaker 1: observable because dark energy is pushing them out of this 550 00:27:51,040 --> 00:27:53,560 Speaker 1: sphere of the observable universe. All the stuff we can 551 00:27:53,600 --> 00:27:55,560 Speaker 1: see because light has had a chance to get to us. 552 00:27:55,960 --> 00:27:59,800 Speaker 1: So galaxies in the sky are disappearing right now, right now, 553 00:28:00,040 --> 00:28:03,880 Speaker 1: quick rush outside of Things that are on the edge 554 00:28:03,880 --> 00:28:06,680 Speaker 1: of our observable universe are disappearing because dark energy is 555 00:28:06,720 --> 00:28:09,000 Speaker 1: pushing them beyond the bounds of things we can see. 556 00:28:09,359 --> 00:28:11,520 Speaker 1: So the nice guy is getting darker and darker. So 557 00:28:11,640 --> 00:28:14,359 Speaker 1: like if you hit the fast forward button on a 558 00:28:14,440 --> 00:28:16,639 Speaker 1: camera point and at the sky, you would see like 559 00:28:17,000 --> 00:28:20,520 Speaker 1: stars just snuff out, just like yeah, you would see 560 00:28:20,520 --> 00:28:24,080 Speaker 1: galaxies snuff out of their clusters of stars. And so 561 00:28:24,119 --> 00:28:27,280 Speaker 1: in that scenario, all these galaxies snuff out of the sky, 562 00:28:27,400 --> 00:28:30,679 Speaker 1: right they get pushed out beyond our observable horizon and 563 00:28:30,720 --> 00:28:34,440 Speaker 1: they disappear, And then we're left with the single galaxy 564 00:28:34,480 --> 00:28:37,680 Speaker 1: in the universe, just like people before Hubble thought, right then, 565 00:28:38,200 --> 00:28:41,320 Speaker 1: and imagine astronomers in the future, right after all these 566 00:28:41,440 --> 00:28:43,920 Speaker 1: galaxies are pushed out, They're gonna think we're the only 567 00:28:44,040 --> 00:28:47,360 Speaker 1: there's only one galaxy in the entire universe. Yeah, because 568 00:28:47,360 --> 00:28:49,760 Speaker 1: they would be the only thing they could see. Right, 569 00:28:49,800 --> 00:28:52,760 Speaker 1: It's amazing to imagine, how to to try to think 570 00:28:52,800 --> 00:28:55,600 Speaker 1: about how could they learn about the universe if all 571 00:28:55,640 --> 00:28:57,480 Speaker 1: they could see was their galaxy? How could they even 572 00:28:57,520 --> 00:29:00,480 Speaker 1: possibly know? Right? They would have no how big it 573 00:29:00,560 --> 00:29:03,600 Speaker 1: actually is. Yeah, they would have no idea what's beyond 574 00:29:03,600 --> 00:29:08,280 Speaker 1: their observa universe. And that's really humbling because it reminds 575 00:29:08,320 --> 00:29:11,200 Speaker 1: you of how little we know. Right, we're, after all, 576 00:29:11,240 --> 00:29:14,240 Speaker 1: fourteen billion years into the history of the universe. There 577 00:29:14,240 --> 00:29:17,120 Speaker 1: could be fascinating clues about the way the universe works 578 00:29:17,120 --> 00:29:19,320 Speaker 1: and what it's made out of that have already been 579 00:29:19,360 --> 00:29:22,560 Speaker 1: pushed beyond our sky that we cannot see and we 580 00:29:22,640 --> 00:29:26,640 Speaker 1: will never see. Right, So what's lost in the night sky? Well, 581 00:29:26,680 --> 00:29:30,520 Speaker 1: we have no idea, right there kinds of galaxies? Who 582 00:29:30,520 --> 00:29:33,720 Speaker 1: knows that we can't see anymore? Yeah, exactly, And continue 583 00:29:33,840 --> 00:29:36,560 Speaker 1: even further, and remember, dark energy is not just out 584 00:29:36,600 --> 00:29:38,680 Speaker 1: there in space. It's here, it's with me, it's with you. 585 00:29:38,760 --> 00:29:41,840 Speaker 1: It's literally pushing me and you apart right now. The 586 00:29:41,960 --> 00:29:45,000 Speaker 1: reason we don't see it is because we have bonds 587 00:29:45,000 --> 00:29:47,560 Speaker 1: that are holding us together, right like their dark energy 588 00:29:47,640 --> 00:29:50,120 Speaker 1: is trying to create new space between the molecules in 589 00:29:50,160 --> 00:29:52,960 Speaker 1: my hand, But the molecules are bound together tightly enough 590 00:29:52,960 --> 00:29:56,520 Speaker 1: to resist that. But if dark energy continues, it might 591 00:29:56,920 --> 00:29:59,880 Speaker 1: eventually shred the Milky Way, right, take our own galaxy 592 00:29:59,880 --> 00:30:02,760 Speaker 1: and tossed the stars out into space. Eventually we might 593 00:30:02,800 --> 00:30:05,320 Speaker 1: just be a solar system floating in the inky blackness 594 00:30:05,360 --> 00:30:09,240 Speaker 1: of space, seeing nothing. Right, that's one potential future, thinking 595 00:30:09,280 --> 00:30:13,520 Speaker 1: that we're the only star in the entire creation, the 596 00:30:13,840 --> 00:30:17,920 Speaker 1: entire universe. That's right, that's right, that's one real possibility. Now, again, 597 00:30:18,240 --> 00:30:20,200 Speaker 1: we don't know what dark energy is gonna do. We 598 00:30:20,200 --> 00:30:21,840 Speaker 1: don't know if it's strong enough to do that. We 599 00:30:21,880 --> 00:30:23,320 Speaker 1: don't know if it's gonna stop. We don't know if 600 00:30:23,360 --> 00:30:26,360 Speaker 1: something else is going to happen. We really have no idea. 601 00:30:26,400 --> 00:30:28,600 Speaker 1: But it's it's amazing to me that it's only this 602 00:30:28,720 --> 00:30:31,840 Speaker 1: knowledge is only twenty years old, twenty years ago before 603 00:30:31,880 --> 00:30:34,520 Speaker 1: we discover the stuff we didn't know that the universe 604 00:30:34,640 --> 00:30:37,040 Speaker 1: was accelerating, and we didn't know that most of the 605 00:30:37,120 --> 00:30:40,320 Speaker 1: universe was this thing called dark energy. Like, think about 606 00:30:40,360 --> 00:30:43,600 Speaker 1: how recent that discovery is. That to me is inspiring 607 00:30:43,640 --> 00:30:46,240 Speaker 1: because it makes me hope that we have more mind 608 00:30:46,240 --> 00:30:48,640 Speaker 1: blowing discoveries ahead, you know, more of these moments of 609 00:30:48,680 --> 00:30:52,480 Speaker 1: like what the universe is totally different from what I imagined. 610 00:30:52,800 --> 00:31:00,320 Speaker 1: That's what I live for in physics. Well, you know, 611 00:31:00,320 --> 00:31:02,360 Speaker 1: this is when it give me. Think. This past weekend, 612 00:31:02,360 --> 00:31:05,920 Speaker 1: I was camping with my kids and my family and 613 00:31:06,200 --> 00:31:08,320 Speaker 1: it was a beautiful night. You could see all the stars. 614 00:31:08,480 --> 00:31:11,480 Speaker 1: And I pointed out to my daughter, was like, look 615 00:31:11,520 --> 00:31:13,160 Speaker 1: at all the stars. And I was pointing out some 616 00:31:13,240 --> 00:31:16,760 Speaker 1: of the constellations and stuff, and she's like wow. And 617 00:31:16,800 --> 00:31:19,280 Speaker 1: I talked pointed out the Big Dipper and she's like, 618 00:31:19,440 --> 00:31:22,280 Speaker 1: that's the Big Dipper. And she proceeded to tell me 619 00:31:22,320 --> 00:31:24,720 Speaker 1: this whole complicated story about the Big Dipper that she 620 00:31:24,760 --> 00:31:27,160 Speaker 1: read in this book she had at school that she's 621 00:31:27,160 --> 00:31:30,320 Speaker 1: read like a million times, but for the first time 622 00:31:30,600 --> 00:31:33,680 Speaker 1: she had actually seen the stars, She had actually seen 623 00:31:33,720 --> 00:31:36,240 Speaker 1: the Big Dipper. What a fun moment for her. Yeah, 624 00:31:36,360 --> 00:31:39,240 Speaker 1: to make to make these things real yeah, yeah, and 625 00:31:39,400 --> 00:31:41,800 Speaker 1: so yeah, so I think that's a big lesson. You know, 626 00:31:41,920 --> 00:31:45,200 Speaker 1: go out there, look at the stars before they go away. 627 00:31:45,400 --> 00:31:47,280 Speaker 1: And this is not abstract. I mean, this is our 628 00:31:47,400 --> 00:31:49,480 Speaker 1: universe we're actually talking about. And you can go along 629 00:31:49,520 --> 00:31:52,040 Speaker 1: and live your life and worry about traffic and paying 630 00:31:52,040 --> 00:31:54,280 Speaker 1: the next bill in your own financial big bang. But 631 00:31:54,400 --> 00:31:57,000 Speaker 1: these things are our context, right, This is the universe 632 00:31:57,080 --> 00:31:59,400 Speaker 1: we live in that we're definitely trying to discover before 633 00:31:59,440 --> 00:32:02,120 Speaker 1: it blow was itself up. It's changing all the time, 634 00:32:02,240 --> 00:32:11,680 Speaker 1: so go out there and experience it. Absolutely. If you 635 00:32:11,800 --> 00:32:14,680 Speaker 1: still have a question after listening to all these explanations, 636 00:32:14,760 --> 00:32:17,720 Speaker 1: please drop us a line. We'd love to hear from you. 637 00:32:17,720 --> 00:32:20,520 Speaker 1: You can find us at Facebook, Twitter, and Instagram at 638 00:32:20,880 --> 00:32:24,000 Speaker 1: Daniel and Jorge that's one word, or email us at 639 00:32:24,280 --> 00:32:31,200 Speaker 1: Feedback at Daniel and Jorge dot com.