1 00:00:00,000 --> 00:00:01,760 Welcome back to Cosmos in a Pod. 2 00:00:01,760 --> 00:00:04,280 We're jumping right back into our Space and Astronomy series 3 00:00:04,280 --> 00:00:05,200 with episode two. 4 00:00:05,200 --> 00:00:06,040 Yeah. 5 00:00:06,040 --> 00:00:10,320 And today, we are going deep on one of the biggest mysteries 6 00:00:10,320 --> 00:00:13,960 in astrophysics, dark matter. 7 00:00:13,960 --> 00:00:16,160 It really is incredible when you think about it. 8 00:00:16,160 --> 00:00:17,000 It is. 9 00:00:17,000 --> 00:00:18,680 Most of the matter in the universe is this stuff 10 00:00:18,680 --> 00:00:20,560 that we can't see or touch. 11 00:00:20,560 --> 00:00:22,120 Yeah, it's like a cosmic riddle. 12 00:00:22,120 --> 00:00:22,960 Right. 13 00:00:22,960 --> 00:00:24,120 How do we even know it's out there? 14 00:00:24,120 --> 00:00:27,600 What was the first clue that something was off? 15 00:00:27,600 --> 00:00:28,980 Well, picture this. 16 00:00:28,980 --> 00:00:32,080 You're watching a merry-go-round spinning super fast. 17 00:00:32,080 --> 00:00:32,880 OK. 18 00:00:32,880 --> 00:00:35,440 You'd expect the horses on the outside to go flying off. 19 00:00:35,440 --> 00:00:36,440 Yeah, makes sense. 20 00:00:36,440 --> 00:00:39,360 But in galaxies, the stars on the outer edges 21 00:00:39,360 --> 00:00:41,880 are moving way faster than they should be, 22 00:00:41,880 --> 00:00:44,520 based on all the stuff we can see, like stars and gas. 23 00:00:44,520 --> 00:00:46,840 So something must be keeping them in place, 24 00:00:46,840 --> 00:00:48,520 providing this extra gravity. 25 00:00:48,520 --> 00:00:49,760 It's like a cosmic glue or something. 26 00:00:49,760 --> 00:00:50,520 Exactly. 27 00:00:50,520 --> 00:00:51,880 That's where dark matter comes in. 28 00:00:51,880 --> 00:00:53,960 This invisible stuff with a ton of gravity, 29 00:00:53,960 --> 00:00:56,120 it doesn't emit or absorb light. 30 00:00:56,120 --> 00:00:59,880 It's like a giant invisible web holding galaxies together. 31 00:00:59,880 --> 00:01:00,480 I see. 32 00:01:00,480 --> 00:01:01,560 Pretty cool, huh? 33 00:01:01,560 --> 00:01:04,320 OK, so we've got these stars zipping around way too fast. 34 00:01:04,320 --> 00:01:05,680 And scientists are like, hold on a second. 35 00:01:05,680 --> 00:01:07,600 There's got to be something else out there. 36 00:01:07,600 --> 00:01:10,800 Who first proposed this idea of dark matter? 37 00:01:10,800 --> 00:01:13,800 That was Fritz Wicke back in the 1930s. 38 00:01:13,800 --> 00:01:15,480 He was studying a group of galaxies 39 00:01:15,480 --> 00:01:17,240 called the Coma Cluster. 40 00:01:17,240 --> 00:01:20,480 And he noticed they were moving way faster than they should, 41 00:01:20,480 --> 00:01:22,320 based on their visible mass. 42 00:01:22,320 --> 00:01:25,080 He even called it dunkelmatery. 43 00:01:25,080 --> 00:01:25,680 What's that? 44 00:01:25,680 --> 00:01:28,120 It's German for dark matter. 45 00:01:28,120 --> 00:01:29,040 Yeah, it's pretty cool. 46 00:01:29,040 --> 00:01:30,040 He was ahead of his time. 47 00:01:30,040 --> 00:01:33,000 But I mean, that's kind of a wild idea from the 1930s. 48 00:01:33,000 --> 00:01:33,920 Oh, absolutely. 49 00:01:33,920 --> 00:01:35,720 People must have thought he was a little crazy. 50 00:01:35,720 --> 00:01:39,160 Yeah, it took a while for people to come around to the idea. 51 00:01:39,160 --> 00:01:41,800 It wasn't until decades later, the 1970s, 52 00:01:41,800 --> 00:01:44,840 when Vera Rubin's work really solidified the idea. 53 00:01:44,840 --> 00:01:45,680 Vera Rubin, oh yeah. 54 00:01:45,680 --> 00:01:47,520 She was studying individual galaxies 55 00:01:47,520 --> 00:01:49,920 and found the stars on the outer edges 56 00:01:49,920 --> 00:01:53,120 were orbiting at the same speed as those closer to the center. 57 00:01:53,120 --> 00:01:55,240 Wait, so the stars further away from the center 58 00:01:55,240 --> 00:01:58,040 of the galaxy are moving just as fast as those closer in? 59 00:01:58,040 --> 00:01:58,880 Exactly. 60 00:01:58,880 --> 00:02:00,240 It shouldn't be like that. 61 00:02:00,240 --> 00:02:03,480 Yeah, you would think they would be moving slower, 62 00:02:03,480 --> 00:02:05,320 because they are farther away. 63 00:02:05,320 --> 00:02:09,280 If only the stuff we can see, like stars and gas, 64 00:02:09,280 --> 00:02:13,160 was responsible for gravity, then yeah, those outer stars 65 00:02:13,160 --> 00:02:15,360 should be moving slower. 66 00:02:15,360 --> 00:02:16,400 But they're not. 67 00:02:16,400 --> 00:02:18,800 And the only way to explain that is? 68 00:02:18,800 --> 00:02:22,120 Well, there has to be a lot of invisible matter 69 00:02:22,120 --> 00:02:24,080 adding its own gravitational pull. 70 00:02:24,080 --> 00:02:27,040 So Vera Rubin's observations pretty much clinched it. 71 00:02:27,040 --> 00:02:27,880 Yeah, pretty much. 72 00:02:27,880 --> 00:02:29,320 There's something invisible out there 73 00:02:29,320 --> 00:02:31,120 affecting how galaxies move. 74 00:02:31,120 --> 00:02:31,960 Right. 75 00:02:31,960 --> 00:02:33,400 But the big question remains. 76 00:02:33,400 --> 00:02:34,320 What is it? 77 00:02:34,320 --> 00:02:35,760 What is dark matter? 78 00:02:35,760 --> 00:02:36,560 Yeah. 79 00:02:36,560 --> 00:02:37,960 Do we know? 80 00:02:37,960 --> 00:02:39,680 We don't know for sure. 81 00:02:39,680 --> 00:02:40,160 Really? 82 00:02:40,160 --> 00:02:42,160 That's the million dollar question. 83 00:02:42,160 --> 00:02:43,600 Scientists are working hard on it. 84 00:02:43,600 --> 00:02:44,080 I bet. 85 00:02:44,080 --> 00:02:45,440 It's a really tough problem. 86 00:02:45,440 --> 00:02:47,840 OK, so what are some of the leading ideas? 87 00:02:47,840 --> 00:02:50,760 Well, one of the top contenders is something called Wimpy's. 88 00:02:50,760 --> 00:02:51,680 Wimps? 89 00:02:51,680 --> 00:02:54,560 Yeah, short for Weakly Interacting Massive Particles. 90 00:02:54,560 --> 00:02:55,640 OK, I got to ask. 91 00:02:55,640 --> 00:02:56,200 What's that? 92 00:02:56,200 --> 00:02:57,280 What does that even mean? 93 00:02:57,280 --> 00:02:58,200 Break it down for me. 94 00:02:58,200 --> 00:02:58,720 Sure. 95 00:02:58,720 --> 00:03:01,320 Essentially, wimps are hypothetical particles 96 00:03:01,320 --> 00:03:04,240 that are thought to be heavy, but don't interact 97 00:03:04,240 --> 00:03:06,320 much with normal matter. 98 00:03:06,320 --> 00:03:08,000 So they just kind of pass right through us. 99 00:03:08,000 --> 00:03:09,400 Like cosmic ghosts. 100 00:03:09,400 --> 00:03:10,200 Exactly. 101 00:03:10,200 --> 00:03:12,400 So they are massive, but they don't 102 00:03:12,400 --> 00:03:14,200 like to interact with the other particles. 103 00:03:14,200 --> 00:03:15,880 Yeah, they like to keep to themselves. 104 00:03:15,880 --> 00:03:17,800 And that makes them pretty hard to detect, I imagine. 105 00:03:17,800 --> 00:03:18,440 You got it. 106 00:03:18,440 --> 00:03:19,640 Is that why we haven't found them yet? 107 00:03:19,640 --> 00:03:20,640 Pretty much, yeah. 108 00:03:20,640 --> 00:03:22,760 So how are scientists looking for them? 109 00:03:22,760 --> 00:03:27,240 They've built super sensitive detectors deep underground 110 00:03:27,240 --> 00:03:29,120 to try and catch them. 111 00:03:29,120 --> 00:03:30,240 Deep underground? 112 00:03:30,240 --> 00:03:31,080 Why? 113 00:03:31,080 --> 00:03:31,560 Well. 114 00:03:31,560 --> 00:03:33,360 Is that like a mine or something? 115 00:03:33,360 --> 00:03:34,960 It has to be shielded, right. 116 00:03:34,960 --> 00:03:35,320 Oh, I see. 117 00:03:35,320 --> 00:03:35,840 OK. 118 00:03:35,840 --> 00:03:38,520 So it can't be disturbed by cosmic rays and things. 119 00:03:38,520 --> 00:03:42,040 The idea is that if a wimpy passes through, 120 00:03:42,040 --> 00:03:45,120 it might bump into an atom and create a signal. 121 00:03:45,120 --> 00:03:46,640 So they're setting a trap, hoping 122 00:03:46,640 --> 00:03:49,640 that a cosmic ghost will bump into it. 123 00:03:49,640 --> 00:03:51,000 Kind of, yeah. 124 00:03:51,000 --> 00:03:54,080 And some experiments have reported some interesting hints. 125 00:03:54,080 --> 00:03:54,760 Have they? 126 00:03:54,760 --> 00:03:57,720 But we need more data before we can say for sure. 127 00:03:57,720 --> 00:03:59,600 So we're on the edge of our seats waiting. 128 00:03:59,600 --> 00:04:00,280 We are. 129 00:04:00,280 --> 00:04:03,480 It would be huge if they definitively found one. 130 00:04:03,480 --> 00:04:05,520 Yeah, it would be a game changer for physics. 131 00:04:05,520 --> 00:04:07,520 OK, so we've got these underground detectors 132 00:04:07,520 --> 00:04:08,640 trying to catch wimps. 133 00:04:08,640 --> 00:04:09,480 Right. 134 00:04:09,480 --> 00:04:11,960 But you also mentioned particle accelerators earlier. 135 00:04:11,960 --> 00:04:12,460 Yes. 136 00:04:12,460 --> 00:04:14,480 How do those fit into this? 137 00:04:14,480 --> 00:04:15,600 It's a different approach. 138 00:04:15,600 --> 00:04:18,000 It's like the opposite of underground detectors. 139 00:04:18,000 --> 00:04:18,680 How so? 140 00:04:18,680 --> 00:04:23,040 Instead of passively waiting, we are trying to create them. 141 00:04:23,040 --> 00:04:24,320 You mean create wimps? 142 00:04:24,320 --> 00:04:25,640 Uh-huh. 143 00:04:25,640 --> 00:04:30,400 By smashing particles together at incredibly high speeds 144 00:04:30,400 --> 00:04:33,600 to replicate the conditions of the early universe. 145 00:04:33,600 --> 00:04:36,200 So we're recreating the Big Bang in the lab. 146 00:04:36,200 --> 00:04:37,320 Kind of, yeah. 147 00:04:37,320 --> 00:04:40,200 And hoping that some dark matter pops out. 148 00:04:40,200 --> 00:04:41,120 Exactly. 149 00:04:41,120 --> 00:04:42,120 That is wild. 150 00:04:42,120 --> 00:04:46,840 The idea is if we recreate those super high energy conditions, 151 00:04:46,840 --> 00:04:49,480 we might produce dark matter as a byproduct. 152 00:04:49,480 --> 00:04:50,240 Mm, I see. 153 00:04:50,240 --> 00:04:51,200 It's a long shot. 154 00:04:51,200 --> 00:04:53,360 What kind of particle accelerators are we talking about? 155 00:04:53,360 --> 00:04:55,560 The Large Hadron Collider, the LHC. 156 00:04:55,560 --> 00:04:57,000 Oh, yeah, I've heard of that one. 157 00:04:57,000 --> 00:04:58,240 It's the one in Switzerland, right? 158 00:04:58,240 --> 00:04:58,760 Yes. 159 00:04:58,760 --> 00:05:00,680 It's the most powerful one in the world. 160 00:05:00,680 --> 00:05:02,880 So they are smashing atoms together, 161 00:05:02,880 --> 00:05:04,560 hoping to make some dark matter. 162 00:05:04,560 --> 00:05:05,360 That's right. 163 00:05:05,360 --> 00:05:07,600 And if we did create it in the LHC, 164 00:05:07,600 --> 00:05:09,520 we could study it in more detail. 165 00:05:09,520 --> 00:05:11,800 OK, so two approaches then. 166 00:05:11,800 --> 00:05:14,400 Sensitive detectors searching for wimps underground. 167 00:05:14,400 --> 00:05:15,280 Right. 168 00:05:15,280 --> 00:05:17,280 And powerful particle accelerators 169 00:05:17,280 --> 00:05:19,880 trying to create them by smashing things together. 170 00:05:19,880 --> 00:05:20,800 Exactly. 171 00:05:20,800 --> 00:05:22,760 Sounds like scientists are covering all their bases. 172 00:05:22,760 --> 00:05:24,720 Yeah, we need to use every tool we have 173 00:05:24,720 --> 00:05:27,160 to try and crack this mystery. 174 00:05:27,160 --> 00:05:30,720 All right, so let's say we do figure out what dark matter is. 175 00:05:30,720 --> 00:05:31,240 Yeah. 176 00:05:31,240 --> 00:05:32,400 What could we learn? 177 00:05:32,400 --> 00:05:35,120 You mentioned earlier it could have big implications. 178 00:05:35,120 --> 00:05:36,280 Absolutely. 179 00:05:36,280 --> 00:05:38,640 For physics and even lead to new technologies. 180 00:05:38,640 --> 00:05:41,320 Yeah, first of all, identifying dark matter 181 00:05:41,320 --> 00:05:43,840 would complete our picture of the universe's 182 00:05:43,840 --> 00:05:46,600 fundamental building blocks. 183 00:05:46,600 --> 00:05:49,240 You see, our best model of particle physics, 184 00:05:49,240 --> 00:05:52,680 called the standard model, doesn't include dark matter. 185 00:05:52,680 --> 00:05:53,200 OK. 186 00:05:53,200 --> 00:05:56,400 It doesn't even explain what it is or how it works. 187 00:05:56,400 --> 00:05:58,120 So finding dark matter would force 188 00:05:58,120 --> 00:06:01,040 us to change or extend the standard model. 189 00:06:01,040 --> 00:06:03,400 It would be like rewriting the physics textbooks. 190 00:06:03,400 --> 00:06:04,520 Basically, yeah. 191 00:06:04,520 --> 00:06:07,320 It's a huge step forward in understanding the universe. 192 00:06:07,320 --> 00:06:08,720 At the most fundamental level. 193 00:06:08,720 --> 00:06:10,560 At the most fundamental level. 194 00:06:10,560 --> 00:06:13,160 And who knows what new mysteries we might uncover. 195 00:06:13,160 --> 00:06:13,880 Exactly. 196 00:06:13,880 --> 00:06:15,840 Maybe even whole new areas of research 197 00:06:15,840 --> 00:06:17,200 we can't even imagine yet. 198 00:06:17,200 --> 00:06:18,280 It's possible. 199 00:06:18,280 --> 00:06:19,040 This is incredible. 200 00:06:19,040 --> 00:06:19,520 Isn't it? 201 00:06:19,520 --> 00:06:22,080 So it's not just about figuring out a scientific puzzle. 202 00:06:22,080 --> 00:06:24,320 There could be real world applications too. 203 00:06:24,320 --> 00:06:25,320 Definitely. 204 00:06:25,320 --> 00:06:28,040 Throughout history, breakthroughs in physics 205 00:06:28,040 --> 00:06:30,280 have often led to new technologies 206 00:06:30,280 --> 00:06:31,720 that change the world. 207 00:06:31,720 --> 00:06:32,880 Like electricity. 208 00:06:32,880 --> 00:06:33,960 Exactly. 209 00:06:33,960 --> 00:06:35,320 Or computers. 210 00:06:35,320 --> 00:06:37,520 It all started with understanding physics. 211 00:06:37,520 --> 00:06:39,120 So what kind of technologies are we 212 00:06:39,120 --> 00:06:41,880 talking about when it comes to dark matter? 213 00:06:41,880 --> 00:06:43,320 What could it be used for? 214 00:06:43,320 --> 00:06:46,280 It's hard to say for sure, but the possibilities 215 00:06:46,280 --> 00:06:47,760 are pretty amazing. 216 00:06:47,760 --> 00:06:48,720 Give me some examples. 217 00:06:48,720 --> 00:06:49,200 OK. 218 00:06:49,200 --> 00:06:51,560 Well, if we learn how to manipulate it, 219 00:06:51,560 --> 00:06:54,880 maybe we could use it for spacecraft propulsion 220 00:06:54,880 --> 00:06:56,840 or new forms of energy. 221 00:06:56,840 --> 00:06:59,600 So like spaceships powered by dark matter. 222 00:06:59,600 --> 00:07:01,760 It sounds like science fiction, but it's not 223 00:07:01,760 --> 00:07:03,080 entirely out of the question. 224 00:07:03,080 --> 00:07:03,960 That's amazing. 225 00:07:03,960 --> 00:07:06,080 Or maybe even new ways to communicate. 226 00:07:06,080 --> 00:07:07,440 Yeah, it's possible. 227 00:07:07,440 --> 00:07:08,560 Wow. 228 00:07:08,560 --> 00:07:12,720 So revolutionizing physics, new technologies, spaceships. 229 00:07:12,720 --> 00:07:14,840 But there's also something almost philosophical 230 00:07:14,840 --> 00:07:17,560 about this whole quest for dark matter, isn't there? 231 00:07:17,560 --> 00:07:18,600 Oh, absolutely. 232 00:07:18,600 --> 00:07:21,080 It's humbling to realize we're surrounded 233 00:07:21,080 --> 00:07:24,240 by this vast invisible universe. 234 00:07:24,240 --> 00:07:24,760 It's true. 235 00:07:24,760 --> 00:07:26,600 We're only beginning to understand. 236 00:07:26,600 --> 00:07:28,160 Shows how much we still don't know. 237 00:07:28,160 --> 00:07:31,000 Yeah, it's like an invitation to keep exploring, 238 00:07:31,000 --> 00:07:33,000 to keep pushing the limits of what we know. 239 00:07:33,000 --> 00:07:33,480 Absolutely. 240 00:07:33,480 --> 00:07:35,400 And to never stop asking questions. 241 00:07:35,400 --> 00:07:35,960 Exactly. 242 00:07:35,960 --> 00:07:37,560 The more we learn about the universe, 243 00:07:37,560 --> 00:07:40,360 the more we realize how much more there is to learn. 244 00:07:40,360 --> 00:07:41,120 Right. 245 00:07:41,120 --> 00:07:44,240 OK, so we've covered a lot of ground, 246 00:07:44,240 --> 00:07:46,400 the evidence for dark matter, the ongoing efforts 247 00:07:46,400 --> 00:07:47,480 to understand it. 248 00:07:47,480 --> 00:07:48,960 But there's one more aspect I want 249 00:07:48,960 --> 00:07:50,320 to touch on before we wrap up. 250 00:07:50,320 --> 00:07:51,040 What's that? 251 00:07:51,040 --> 00:07:52,840 The implications of dark matter for the fate 252 00:07:52,840 --> 00:07:53,840 of the universe itself. 253 00:07:53,840 --> 00:07:54,560 Oh, wow. 254 00:07:54,560 --> 00:07:55,000 OK. 255 00:07:55,000 --> 00:07:55,880 We're thinking big now. 256 00:07:55,880 --> 00:07:57,200 We are. 257 00:07:57,200 --> 00:07:59,640 Yeah, it really is fascinating the scale of it all. 258 00:07:59,640 --> 00:08:00,140 It is. 259 00:08:00,140 --> 00:08:02,840 85% of the matter in the universe. 260 00:08:02,840 --> 00:08:04,760 And we still have no idea what it is. 261 00:08:04,760 --> 00:08:05,800 It's humbling, really. 262 00:08:05,800 --> 00:08:06,480 It really is. 263 00:08:06,480 --> 00:08:09,520 So we talked about gravitational lensing and simulations. 264 00:08:09,520 --> 00:08:10,040 Yeah. 265 00:08:10,040 --> 00:08:12,720 Are there other ways we are trying to pin down 266 00:08:12,720 --> 00:08:14,720 what dark matter is? 267 00:08:14,720 --> 00:08:15,600 There are. 268 00:08:15,600 --> 00:08:17,000 OK, tell me more. 269 00:08:17,000 --> 00:08:20,600 Well, one approach is to try and detect the particles directly. 270 00:08:20,600 --> 00:08:21,120 Directly. 271 00:08:21,120 --> 00:08:23,000 You mean like catch a dark matter particle? 272 00:08:23,000 --> 00:08:23,680 Yeah, kind of. 273 00:08:23,680 --> 00:08:24,920 It's a huge challenge, though. 274 00:08:24,920 --> 00:08:25,840 I can imagine. 275 00:08:25,840 --> 00:08:28,720 These particles barely interact with normal matter, right? 276 00:08:28,720 --> 00:08:29,480 That's right. 277 00:08:29,480 --> 00:08:33,880 But scientists have built some incredibly sensitive detectors, 278 00:08:33,880 --> 00:08:36,480 often located deep underground, to try and find them. 279 00:08:36,480 --> 00:08:37,520 Deep underground? 280 00:08:37,520 --> 00:08:38,040 Yeah. 281 00:08:38,040 --> 00:08:40,240 They have to be shielded from all the background noise. 282 00:08:40,240 --> 00:08:40,760 Oh, OK. 283 00:08:40,760 --> 00:08:41,760 Yeah. 284 00:08:41,760 --> 00:08:42,560 Makes sense. 285 00:08:42,560 --> 00:08:45,000 Cosmic rays and other radiation could 286 00:08:45,000 --> 00:08:46,360 interfere with the measurements. 287 00:08:46,360 --> 00:08:49,360 So you need to go deep to create a quiet environment. 288 00:08:49,360 --> 00:08:50,000 Exactly. 289 00:08:50,000 --> 00:08:52,920 To increase the chances of detecting a dark matter particle. 290 00:08:52,920 --> 00:08:53,920 That's the idea. 291 00:08:53,920 --> 00:08:56,000 And have these experiments found anything? 292 00:08:56,000 --> 00:08:58,960 There have been a few tantalizing hints. 293 00:08:58,960 --> 00:08:59,600 Really? 294 00:08:59,600 --> 00:09:02,200 A few signals that could be from dark matter. 295 00:09:02,200 --> 00:09:02,760 Wow. 296 00:09:02,760 --> 00:09:04,560 But we need more data to confirm. 297 00:09:04,560 --> 00:09:06,880 So everyone is on the edge of their seats waiting. 298 00:09:06,880 --> 00:09:07,880 Pretty much. 299 00:09:07,880 --> 00:09:09,680 If we could definitely detect a particle. 300 00:09:09,680 --> 00:09:10,760 It would be huge. 301 00:09:10,760 --> 00:09:11,240 Yeah. 302 00:09:11,240 --> 00:09:13,240 A game changer for physics. 303 00:09:13,240 --> 00:09:15,920 You mentioned these detectors are often located in mines 304 00:09:15,920 --> 00:09:16,440 or something. 305 00:09:16,440 --> 00:09:17,400 Yeah, sometimes. 306 00:09:17,400 --> 00:09:20,080 It's amazing what lengths scientists will go to. 307 00:09:20,080 --> 00:09:20,640 It is. 308 00:09:20,640 --> 00:09:22,720 Just to try to study this invisible universe. 309 00:09:22,720 --> 00:09:27,000 It's a real testament to human curiosity and ingenuity. 310 00:09:27,000 --> 00:09:28,680 Absolutely. 311 00:09:28,680 --> 00:09:32,000 OK, so we've got these underground detectors. 312 00:09:32,000 --> 00:09:34,120 But you also mentioned particle accelerators. 313 00:09:34,120 --> 00:09:34,760 Yeah. 314 00:09:34,760 --> 00:09:36,840 So how do those fit into all of this? 315 00:09:36,840 --> 00:09:38,360 It's a completely different approach. 316 00:09:38,360 --> 00:09:40,320 Kind of the opposite of underground detectors. 317 00:09:40,320 --> 00:09:40,840 Also. 318 00:09:40,840 --> 00:09:43,160 With the detectors, we are passively 319 00:09:43,160 --> 00:09:45,440 waiting for a particle to come to us. 320 00:09:45,440 --> 00:09:46,120 OK, yeah. 321 00:09:46,120 --> 00:09:48,460 But with accelerators, we're actively 322 00:09:48,460 --> 00:09:50,520 trying to create them ourselves. 323 00:09:50,520 --> 00:09:51,640 Create dark matter. 324 00:09:51,640 --> 00:09:54,560 Yeah, by smashing particles together 325 00:09:54,560 --> 00:09:56,280 at incredibly high speeds. 326 00:09:56,280 --> 00:09:57,320 Like super fast. 327 00:09:57,320 --> 00:09:58,920 Extremely high energies, yeah. 328 00:09:58,920 --> 00:10:00,560 To try and recreate the conditions 329 00:10:00,560 --> 00:10:01,480 of the early universe. 330 00:10:01,480 --> 00:10:02,200 Exactly. 331 00:10:02,200 --> 00:10:04,720 Like a mini Big Bang in the lab. 332 00:10:04,720 --> 00:10:08,120 Hoping that some dark matter pops out. 333 00:10:08,120 --> 00:10:10,280 And what kind of particle accelerators can do that? 334 00:10:10,280 --> 00:10:11,880 The Large Hadron Collider, for example. 335 00:10:11,880 --> 00:10:12,360 Oh, yeah. 336 00:10:12,360 --> 00:10:13,240 The LHC. 337 00:10:13,240 --> 00:10:14,280 The one in Switzerland. 338 00:10:14,280 --> 00:10:15,840 It's the biggest and most powerful one, right? 339 00:10:15,840 --> 00:10:16,440 It is. 340 00:10:16,440 --> 00:10:19,160 They smash atoms together at near light speed. 341 00:10:19,160 --> 00:10:19,960 Pretty much, yeah. 342 00:10:19,960 --> 00:10:21,400 Hoping to create dark matter. 343 00:10:21,400 --> 00:10:22,640 It's a long shot. 344 00:10:22,640 --> 00:10:26,120 But if it worked, we could study those particles directly. 345 00:10:26,120 --> 00:10:27,200 It would be a breakthrough. 346 00:10:27,200 --> 00:10:28,400 Yeah, it would be. 347 00:10:28,400 --> 00:10:30,720 OK, so we have these two main approaches 348 00:10:30,720 --> 00:10:31,920 to finding dark matter. 349 00:10:31,920 --> 00:10:32,680 That's right. 350 00:10:32,680 --> 00:10:36,000 Sensitive detectors looking for interactions underground. 351 00:10:36,000 --> 00:10:38,160 And powerful accelerators trying to create 352 00:10:38,160 --> 00:10:39,240 the particles directly. 353 00:10:39,240 --> 00:10:39,960 Yeah. 354 00:10:39,960 --> 00:10:42,080 Scientists are really pulling out all the stops. 355 00:10:42,080 --> 00:10:42,720 We have to. 356 00:10:42,720 --> 00:10:44,040 It's a tough problem. 357 00:10:44,040 --> 00:10:47,240 Let's say we do find out what dark matter is. 358 00:10:47,240 --> 00:10:47,760 Yeah. 359 00:10:47,760 --> 00:10:49,200 What could we learn? 360 00:10:49,200 --> 00:10:51,640 You mentioned it could revolutionize physics. 361 00:10:51,640 --> 00:10:52,720 Oh, absolutely. 362 00:10:52,720 --> 00:10:54,160 And lead to new technologies. 363 00:10:54,160 --> 00:10:55,880 What kind of things are we talking about? 364 00:10:55,880 --> 00:10:57,880 Well, first off, finding dark matter 365 00:10:57,880 --> 00:11:00,640 would complete our understanding of the fundamental 366 00:11:00,640 --> 00:11:02,320 building blocks of the universe. 367 00:11:02,320 --> 00:11:03,120 Oh, yeah? 368 00:11:03,120 --> 00:11:05,800 Our current best model of particle physics, 369 00:11:05,800 --> 00:11:08,240 the Standard Model, doesn't explain it. 370 00:11:08,240 --> 00:11:09,720 So it'd be a big change for physics. 371 00:11:09,720 --> 00:11:10,560 A huge change. 372 00:11:10,560 --> 00:11:12,200 We'd have to extend the Standard Model 373 00:11:12,200 --> 00:11:13,440 or come up with a new one. 374 00:11:13,440 --> 00:11:15,840 And that would open up whole new areas of research, I imagine. 375 00:11:15,840 --> 00:11:16,520 It would. 376 00:11:16,520 --> 00:11:18,680 Maybe even whole new fields of physics. 377 00:11:18,680 --> 00:11:20,800 So it's not just about satisfying our curiosity. 378 00:11:20,800 --> 00:11:22,720 There could be real world applications, too. 379 00:11:22,720 --> 00:11:23,880 Oh, for sure. 380 00:11:23,880 --> 00:11:26,280 Throughout history, discoveries in physics 381 00:11:26,280 --> 00:11:29,240 have often led to amazing technologies. 382 00:11:29,240 --> 00:11:30,800 Yeah, like electricity and computers. 383 00:11:30,800 --> 00:11:31,520 Exactly. 384 00:11:31,520 --> 00:11:34,440 Well, what kind of technologies could dark matter lead to? 385 00:11:34,440 --> 00:11:36,960 It's hard to say exactly, but maybe things 386 00:11:36,960 --> 00:11:38,720 like spacecraft propulsion. 387 00:11:38,720 --> 00:11:40,960 Spaceships powered by dark matter. 388 00:11:40,960 --> 00:11:41,720 Maybe. 389 00:11:41,720 --> 00:11:43,000 Wow, that's incredible. 390 00:11:43,000 --> 00:11:46,800 Or new forms of energy or communication technologies. 391 00:11:46,800 --> 00:11:48,560 This is mind blowing. 392 00:11:48,560 --> 00:11:53,080 Revolutionizing physics, spaceships, new energy sources. 393 00:11:53,080 --> 00:11:53,800 It's incredible. 394 00:11:53,800 --> 00:11:54,440 It really is. 395 00:11:54,440 --> 00:11:55,880 But there's also something bigger than that. 396 00:11:55,880 --> 00:11:56,880 What do you mean? 397 00:11:56,880 --> 00:12:00,920 Well, this whole quest to understand dark matter, 398 00:12:00,920 --> 00:12:02,360 it's almost philosophical, isn't it? 399 00:12:02,360 --> 00:12:04,000 I think so, yes. 400 00:12:04,000 --> 00:12:05,200 It's very humbling. 401 00:12:05,200 --> 00:12:08,920 To realize we're surrounded by this vast, invisible universe. 402 00:12:08,920 --> 00:12:10,800 And we're just starting to understand it. 403 00:12:10,800 --> 00:12:14,360 It really makes you appreciate how much we don't know. 404 00:12:14,360 --> 00:12:15,120 It does. 405 00:12:15,120 --> 00:12:16,760 And inspires us to keep searching. 406 00:12:16,760 --> 00:12:17,560 Absolutely. 407 00:12:17,560 --> 00:12:18,640 The fate of the universe. 408 00:12:18,640 --> 00:12:19,160 Yeah. 409 00:12:19,160 --> 00:12:21,200 OK, so how does dark matter play into that? 410 00:12:21,200 --> 00:12:23,040 Well, it all comes down to gravity. 411 00:12:23,040 --> 00:12:26,000 Dark matter's gravity is what holds galaxies and galaxy 412 00:12:26,000 --> 00:12:27,680 clusters together. 413 00:12:27,680 --> 00:12:30,840 But it also affects the universe's expansion. 414 00:12:30,840 --> 00:12:31,440 Wait a minute. 415 00:12:31,440 --> 00:12:34,040 I thought the universe was constantly expanding. 416 00:12:34,040 --> 00:12:37,400 How can it be holding things together and expanding 417 00:12:37,400 --> 00:12:38,760 at the same time? 418 00:12:38,760 --> 00:12:40,520 It's a bit of a tug of war. 419 00:12:40,520 --> 00:12:41,040 OK. 420 00:12:41,040 --> 00:12:44,440 You see the Big Bang started the universe expanding outward. 421 00:12:44,440 --> 00:12:44,960 Yeah. 422 00:12:44,960 --> 00:12:48,040 But gravity wants to pull everything back together. 423 00:12:48,040 --> 00:12:49,800 And dark matter, because it makes up 424 00:12:49,800 --> 00:12:52,480 so much of the universe's mass, it 425 00:12:52,480 --> 00:12:54,960 has a really strong gravitational pull. 426 00:12:54,960 --> 00:12:57,120 So dark matter is kind of slowing down the expansion. 427 00:12:57,120 --> 00:12:58,200 Like a cosmic break. 428 00:12:58,200 --> 00:12:58,920 Yeah. 429 00:12:58,920 --> 00:13:01,400 So the question is, how strong is that break? 430 00:13:01,400 --> 00:13:02,400 Exactly. 431 00:13:02,400 --> 00:13:04,320 Will it eventually stop the expansion 432 00:13:04,320 --> 00:13:06,120 and cause the universe to collapse? 433 00:13:06,120 --> 00:13:07,280 It's possible. 434 00:13:07,280 --> 00:13:09,920 Or will the expansion just keep going forever? 435 00:13:09,920 --> 00:13:10,960 That's the big question. 436 00:13:10,960 --> 00:13:13,600 Leading to a cold, empty universe. 437 00:13:13,600 --> 00:13:15,880 What do scientists think is more likely? 438 00:13:15,880 --> 00:13:17,480 It depends on a couple of things. 439 00:13:17,480 --> 00:13:19,880 How much dark matter is out there and how it's spread out. 440 00:13:19,880 --> 00:13:20,360 OK. 441 00:13:20,360 --> 00:13:22,800 But right now, it looks like the expansion is actually 442 00:13:22,800 --> 00:13:23,880 accelerating. 443 00:13:23,880 --> 00:13:24,520 Accelerating. 444 00:13:24,520 --> 00:13:25,020 Wait. 445 00:13:25,020 --> 00:13:27,200 So it's expanding faster and faster. 446 00:13:27,200 --> 00:13:28,640 That's what the data suggests. 447 00:13:28,640 --> 00:13:29,360 Wow. 448 00:13:29,360 --> 00:13:31,120 And that's where another mystery comes in. 449 00:13:31,120 --> 00:13:32,440 Dark energy. 450 00:13:32,440 --> 00:13:33,080 Dark energy. 451 00:13:33,080 --> 00:13:33,580 Hold on. 452 00:13:33,580 --> 00:13:34,560 You're losing me. 453 00:13:34,560 --> 00:13:35,920 We're still trying to figure out dark matter. 454 00:13:35,920 --> 00:13:37,400 And now there's dark energy too. 455 00:13:37,400 --> 00:13:38,200 I know it's a lot. 456 00:13:38,200 --> 00:13:40,840 But dark energy is another invisible force. 457 00:13:40,840 --> 00:13:41,360 OK. 458 00:13:41,360 --> 00:13:43,120 That seems to be pushing everything apart. 459 00:13:43,120 --> 00:13:44,560 So it's like anti-gravity. 460 00:13:44,560 --> 00:13:45,200 Exactly. 461 00:13:45,200 --> 00:13:47,400 A repulsive force that counteracts gravity. 462 00:13:47,400 --> 00:13:50,080 So dark matter pulls things together. 463 00:13:50,080 --> 00:13:51,920 Dark energy pushes them apart. 464 00:13:51,920 --> 00:13:52,440 Yeah. 465 00:13:52,440 --> 00:13:54,040 It's a cosmic balancing act. 466 00:13:54,040 --> 00:13:55,120 So what happens next? 467 00:13:55,120 --> 00:13:57,960 Does the universe expand forever or collapse? 468 00:13:57,960 --> 00:14:00,560 It depends on which force is stronger. 469 00:14:00,560 --> 00:14:02,720 Dark matter or dark energy. 470 00:14:02,720 --> 00:14:05,160 So dark matter isn't just shaping galaxies. 471 00:14:05,160 --> 00:14:07,520 It's also tied to the fate of the universe itself. 472 00:14:07,520 --> 00:14:08,440 Absolutely. 473 00:14:08,440 --> 00:14:09,520 That's incredible. 474 00:14:09,520 --> 00:14:12,640 We started with wondering why galaxies don't fly apart. 475 00:14:12,640 --> 00:14:14,840 And now we're talking about the end of the universe. 476 00:14:14,840 --> 00:14:16,880 It's amazing how these things are connected. 477 00:14:16,880 --> 00:14:17,880 It really is. 478 00:14:17,880 --> 00:14:21,360 So dark matter is key to understanding not just 479 00:14:21,360 --> 00:14:23,200 galaxies, but the entire universe. 480 00:14:23,200 --> 00:14:24,560 And everything in it. 481 00:14:24,560 --> 00:14:26,160 Well, this has been an incredible journey. 482 00:14:26,160 --> 00:14:26,800 It has. 483 00:14:26,800 --> 00:14:28,200 We've learned so much. 484 00:14:28,200 --> 00:14:30,760 But it feels like we've only scratched the surface. 485 00:14:30,760 --> 00:14:32,200 There's always more to learn. 486 00:14:32,200 --> 00:14:33,600 That's the beauty of science, right? 487 00:14:33,600 --> 00:14:34,360 Absolutely. 488 00:14:34,360 --> 00:14:36,040 Every answer leads to more questions. 489 00:14:36,040 --> 00:14:38,280 And that's what keeps us going. 490 00:14:38,280 --> 00:14:40,000 Well, I want to thank you for joining us 491 00:14:40,000 --> 00:14:42,400 on this deep dive into the mysteries of dark matter. 492 00:14:42,400 --> 00:14:43,760 It's been my pleasure. 493 00:14:43,760 --> 00:14:46,680 And if you're as fascinated by the universe as we are, 494 00:14:46,680 --> 00:14:50,280 be sure to subscribe to Cosmos in a pod for more explorations 495 00:14:50,280 --> 00:14:51,920 of the cosmos. 496 00:14:51,920 --> 00:14:52,880 We'll see you next time. 497 00:14:52,880 --> 00:14:54,520 See you then.