1 00:00:00,000 --> 00:00:03,340 Imagine trying to put together a giant puzzle, 2 00:00:03,340 --> 00:00:06,340 but some of the pieces are invisible. 3 00:00:06,340 --> 00:00:08,560 You can see their effects, the gaps they create, 4 00:00:08,560 --> 00:00:11,360 the way they influence the pieces around them. 5 00:00:11,360 --> 00:00:13,780 But those pieces themselves, they just stay hidden. 6 00:00:13,780 --> 00:00:14,480 Yeah. 7 00:00:14,480 --> 00:00:17,240 That's the mystery we're diving into today, dog matter. 8 00:00:17,240 --> 00:00:20,360 This unseen force that makes up a whopping 27% 9 00:00:20,360 --> 00:00:22,300 of the universe. 10 00:00:22,300 --> 00:00:25,360 Welcome to Cosmos, an Applaud Space and Astronomy series. 11 00:00:25,360 --> 00:00:27,360 Yeah, it's a fascinating puzzle. 12 00:00:27,360 --> 00:00:30,120 And it's one that has had astronomers and physicists 13 00:00:30,120 --> 00:00:32,920 scratching their heads for decades now. 14 00:00:32,920 --> 00:00:35,520 OK, so before we get lost in this cosmic fog, 15 00:00:35,520 --> 00:00:36,880 can you help me understand this? 16 00:00:36,880 --> 00:00:38,120 We can't see dark matter. 17 00:00:38,120 --> 00:00:39,920 We can't touch it. 18 00:00:39,920 --> 00:00:41,500 But we're pretty sure it's out there. 19 00:00:41,500 --> 00:00:43,760 What's the evidence that we're not just chasing shadows here? 20 00:00:43,760 --> 00:00:45,480 Well, one of the most compelling pieces of evidence 21 00:00:45,480 --> 00:00:47,800 comes from looking at the way galaxies rotate. 22 00:00:47,800 --> 00:00:48,300 OK. 23 00:00:48,300 --> 00:00:50,200 We can measure the speed of stars orbiting 24 00:00:50,200 --> 00:00:51,740 the center of a galaxy. 25 00:00:51,740 --> 00:00:55,280 And based on the visible matter that we see, stars, gas, dust, 26 00:00:55,280 --> 00:00:58,560 we'd expect those stars farther out to be moving slower, 27 00:00:58,560 --> 00:01:00,840 just like planets in our own solar system. 28 00:01:00,840 --> 00:01:02,680 But that's not what we observe. 29 00:01:02,680 --> 00:01:05,160 So the galaxies are breaking the rules then. 30 00:01:05,160 --> 00:01:06,560 What are they doing instead? 31 00:01:06,560 --> 00:01:08,880 The stars in the outer regions of galaxies 32 00:01:08,880 --> 00:01:11,600 are moving much faster than they should if we only 33 00:01:11,600 --> 00:01:13,240 account for the visible matter. 34 00:01:13,240 --> 00:01:14,040 Oh, wow. 35 00:01:14,040 --> 00:01:17,200 It's as if there's some invisible mass, you know? 36 00:01:17,200 --> 00:01:19,120 Like a halo surrounding each galaxy, 37 00:01:19,120 --> 00:01:21,640 providing this extra gravitational pull 38 00:01:21,640 --> 00:01:23,960 to keep those speeding stars in orbit. 39 00:01:23,960 --> 00:01:26,000 OK, so we've got these speedy stars 40 00:01:26,000 --> 00:01:27,920 hinting at something unseen. 41 00:01:27,920 --> 00:01:29,960 Are there any other clues that point 42 00:01:29,960 --> 00:01:31,600 towards dark matter's existence? 43 00:01:31,600 --> 00:01:32,400 Absolutely. 44 00:01:32,400 --> 00:01:34,960 Another piece of evidence comes from the way light bends 45 00:01:34,960 --> 00:01:36,680 as it travels through the universe. 46 00:01:36,680 --> 00:01:38,840 This is called gravitational lensing. 47 00:01:38,840 --> 00:01:41,400 And it's a direct consequence of Einstein's theory 48 00:01:41,400 --> 00:01:43,080 of general relativity. 49 00:01:43,080 --> 00:01:45,400 Massive objects like galaxy clusters, 50 00:01:45,400 --> 00:01:47,840 they actually warp the fabric of spacetime around them. 51 00:01:47,840 --> 00:01:48,400 Wow. 52 00:01:48,400 --> 00:01:50,000 And this warping, it bends the path 53 00:01:50,000 --> 00:01:51,280 of light passing nearby. 54 00:01:51,280 --> 00:01:54,040 So it's kind of like a cosmic magnifying glass then, 55 00:01:54,040 --> 00:01:56,360 distorting the images of distant galaxies. 56 00:01:56,360 --> 00:01:57,240 Exactly. 57 00:01:57,240 --> 00:02:00,120 And by analyzing these distorted images, 58 00:02:00,120 --> 00:02:02,400 we can actually calculate the amount of mass 59 00:02:02,400 --> 00:02:04,040 that's bending the light. 60 00:02:04,040 --> 00:02:06,120 What's fascinating is that the amount of bending 61 00:02:06,120 --> 00:02:08,280 that we observe is far greater than what 62 00:02:08,280 --> 00:02:11,280 we would expect from just the visible matter in those galaxy 63 00:02:11,280 --> 00:02:11,920 clusters. 64 00:02:11,920 --> 00:02:12,520 Wow. 65 00:02:12,520 --> 00:02:14,560 So again, it points towards this presence 66 00:02:14,560 --> 00:02:18,000 of a significant amount of unseen mass dark matter. 67 00:02:18,000 --> 00:02:20,520 It's starting to feel like the universe is playing a cosmic 68 00:02:20,520 --> 00:02:22,720 game of hide and seek with us. 69 00:02:22,720 --> 00:02:25,000 So let's get to the heart of the mystery here. 70 00:02:25,000 --> 00:02:28,440 What could this elusive dark matter actually be made of? 71 00:02:28,440 --> 00:02:30,400 Well, that's the million dollar question. 72 00:02:30,400 --> 00:02:32,400 And it's a question that has led to a whole bunch 73 00:02:32,400 --> 00:02:35,000 of fascinating and sometimes mind boggling theories. 74 00:02:35,000 --> 00:02:37,480 Yeah, can you walk me through some of the top contenders 75 00:02:37,480 --> 00:02:39,240 on this cosmic suspect list? 76 00:02:39,240 --> 00:02:39,760 Sure. 77 00:02:39,760 --> 00:02:42,680 One of the most popular suspects is a class of particles 78 00:02:42,680 --> 00:02:45,920 called WMPIS, weakly interacting massive particles. 79 00:02:45,920 --> 00:02:46,440 WMPIS. 80 00:02:46,440 --> 00:02:48,040 Now, these are hypothetical particles, 81 00:02:48,040 --> 00:02:50,120 meaning we haven't actually directly observed them yet. 82 00:02:50,120 --> 00:02:50,400 OK. 83 00:02:50,400 --> 00:02:53,960 But they fit nicely into certain theoretical frameworks 84 00:02:53,960 --> 00:02:56,640 that attempt to explain some of these unanswered questions 85 00:02:56,640 --> 00:02:57,880 in particle physics. 86 00:02:57,880 --> 00:03:01,000 So WIPs could solve multiple mysteries at once then. 87 00:03:01,000 --> 00:03:01,800 That's pretty cool. 88 00:03:01,800 --> 00:03:03,800 What makes them so difficult to detect? 89 00:03:03,800 --> 00:03:05,280 Well, their defining characteristic 90 00:03:05,280 --> 00:03:08,440 is right there in the name weakly interacting. 91 00:03:08,440 --> 00:03:11,520 They're thought to interact very weakly with ordinary matter 92 00:03:11,520 --> 00:03:13,600 and light, primarily through gravity. 93 00:03:13,600 --> 00:03:14,120 Oh, I see. 94 00:03:14,120 --> 00:03:15,720 They're kind of like cosmic phantoms, 95 00:03:15,720 --> 00:03:17,680 you know, passing through us and everything else 96 00:03:17,680 --> 00:03:19,440 without leaving much of a trace. 97 00:03:19,440 --> 00:03:22,960 So they're there, but incredibly elusive. 98 00:03:22,960 --> 00:03:25,840 Are there any other suspects in this cosmic lineup? 99 00:03:25,840 --> 00:03:26,720 There is. 100 00:03:26,720 --> 00:03:29,320 Another intriguing candidate is the axion. 101 00:03:29,320 --> 00:03:29,820 OK. 102 00:03:29,820 --> 00:03:32,320 Another hypothetical particle axions 103 00:03:32,320 --> 00:03:35,440 are theorized to be incredibly light, much lighter 104 00:03:35,440 --> 00:03:36,600 than even electrons. 105 00:03:36,600 --> 00:03:37,100 Wow. 106 00:03:37,100 --> 00:03:39,200 And they interact even more weakly than WIMPs. 107 00:03:39,200 --> 00:03:41,520 OK, so if WIMPs are like phantoms or axions, 108 00:03:41,520 --> 00:03:43,040 more like wisps of smoke. 109 00:03:43,040 --> 00:03:44,240 That's a good analogy. 110 00:03:44,240 --> 00:03:46,320 Now, one of the reasons axions are so fascinating 111 00:03:46,320 --> 00:03:47,860 is that they were originally proposed 112 00:03:47,860 --> 00:03:50,240 to solve a different problem in particle physics called 113 00:03:50,240 --> 00:03:52,440 the strong CP problem. 114 00:03:52,440 --> 00:03:54,440 It's a bit technical to get into here, 115 00:03:54,440 --> 00:03:56,080 but essentially it has to do with why 116 00:03:56,080 --> 00:03:58,120 certain nuclear inactions don't violate 117 00:03:58,120 --> 00:04:01,760 a fundamental symmetry of nature called the CP symmetry. 118 00:04:01,760 --> 00:04:03,720 So axions could be tying together 119 00:04:03,720 --> 00:04:06,520 seemingly unrelated areas of physics. 120 00:04:06,520 --> 00:04:07,840 That's pretty neat. 121 00:04:07,840 --> 00:04:10,240 Are there any contenders that are a bit more grounded 122 00:04:10,240 --> 00:04:11,480 in what we can already observe? 123 00:04:11,480 --> 00:04:15,040 Well, there's a category called MACHOs, Massive Compact Halo 124 00:04:15,040 --> 00:04:15,920 Objects. 125 00:04:15,920 --> 00:04:16,480 MACHOs. 126 00:04:16,480 --> 00:04:18,880 These are objects made up of ordinary matter, things 127 00:04:18,880 --> 00:04:21,280 like rogue planets, dim stars, or even 128 00:04:21,280 --> 00:04:22,760 black holes that might be lurking 129 00:04:22,760 --> 00:04:25,120 in the halos of galaxies. 130 00:04:25,120 --> 00:04:27,520 The idea is that if there are enough of these MACHOs, 131 00:04:27,520 --> 00:04:30,640 their combined mass could account for some or even 132 00:04:30,640 --> 00:04:31,720 all of this missing mass. 133 00:04:31,720 --> 00:04:33,580 So instead of some exotic new particles, 134 00:04:33,580 --> 00:04:35,440 it could just be a bunch of familiar objects 135 00:04:35,440 --> 00:04:36,320 hiding in the dark. 136 00:04:36,320 --> 00:04:37,440 That's a possibility. 137 00:04:37,440 --> 00:04:39,560 However, observations and calculations 138 00:04:39,560 --> 00:04:42,980 suggest that MACHOs alone can't account for all the dark matter 139 00:04:42,980 --> 00:04:44,120 that we infer. 140 00:04:44,120 --> 00:04:46,200 It's likely a combination of different things, 141 00:04:46,200 --> 00:04:48,280 both the familiar and the yet to be discovered. 142 00:04:48,280 --> 00:04:49,920 This is getting pretty complex. 143 00:04:49,920 --> 00:04:52,240 Are there any other suspects on this dark matter most 144 00:04:52,240 --> 00:04:52,960 wanted list? 145 00:04:52,960 --> 00:04:54,840 Oh, there are many. 146 00:04:54,840 --> 00:04:57,600 Another intriguing candidate is the sterile neutrino. 147 00:04:57,600 --> 00:04:58,920 Sterile neutrino. 148 00:04:58,920 --> 00:05:01,700 You're probably familiar with regular neutrinos, 149 00:05:01,700 --> 00:05:05,600 those incredibly light, almost massless particles that 150 00:05:05,600 --> 00:05:08,760 zip through the cosmos, rarely interacting with anything. 151 00:05:08,760 --> 00:05:10,600 Yeah, I remember you mentioning them earlier 152 00:05:10,600 --> 00:05:11,680 when we were talking about WIMPs. 153 00:05:11,680 --> 00:05:12,180 Right. 154 00:05:12,180 --> 00:05:14,440 They are indeed weakly interacting as well. 155 00:05:14,440 --> 00:05:17,360 Well, sterile neutrinos are a hypothetical type of neutrino 156 00:05:17,360 --> 00:05:19,160 that are even more elusive. 157 00:05:19,160 --> 00:05:20,880 They wouldn't interact with the weak force, 158 00:05:20,880 --> 00:05:23,840 like regular neutrinos, only through gravity, 159 00:05:23,840 --> 00:05:26,760 making them incredibly difficult to detect. 160 00:05:26,760 --> 00:05:27,280 Wow. 161 00:05:27,280 --> 00:05:29,880 However, some theoretical models suggest 162 00:05:29,880 --> 00:05:32,040 that they could be produced in the early universe 163 00:05:32,040 --> 00:05:34,440 and contribute to the dark matter puzzle. 164 00:05:34,440 --> 00:05:37,800 So we have these hypothetical particles, WIMPs, axions, 165 00:05:37,800 --> 00:05:39,120 sterile neutrinos. 166 00:05:39,120 --> 00:05:40,880 They seem to be the prime suspects. 167 00:05:40,880 --> 00:05:42,920 Are there any other radically different approaches 168 00:05:42,920 --> 00:05:45,680 to solving this dark matter mystery? 169 00:05:45,680 --> 00:05:46,680 There are. 170 00:05:46,680 --> 00:05:48,520 Some physicists believe that we might not 171 00:05:48,520 --> 00:05:50,120 need new particles at all. 172 00:05:50,120 --> 00:05:52,120 They propose that our understanding of gravity 173 00:05:52,120 --> 00:05:53,480 might be incomplete. 174 00:05:53,480 --> 00:05:55,600 Perhaps instead of invisible particles lurking 175 00:05:55,600 --> 00:05:57,400 in the shadows, it's the force of gravity 176 00:05:57,400 --> 00:05:59,780 itself that behaves differently on galactic scales 177 00:05:59,780 --> 00:06:01,360 than we currently predict. 178 00:06:01,360 --> 00:06:02,840 So instead of adding new ingredients 179 00:06:02,840 --> 00:06:04,800 to the cosmic recipe, we might need 180 00:06:04,800 --> 00:06:06,440 to tweak the cooking instructions. 181 00:06:06,440 --> 00:06:07,640 Precisely. 182 00:06:07,640 --> 00:06:11,180 This approach is known as modified Newtonian dynamics, 183 00:06:11,180 --> 00:06:13,280 or MOND for short. 184 00:06:13,280 --> 00:06:13,920 MOD. 185 00:06:13,920 --> 00:06:16,680 These theories try to explain the observed discrepancies 186 00:06:16,680 --> 00:06:19,800 in galaxy rotation without invoking dark matter. 187 00:06:19,800 --> 00:06:21,560 They suggest that gravity's pull might 188 00:06:21,560 --> 00:06:23,760 be stronger than predicted by Newton's law 189 00:06:23,760 --> 00:06:27,840 of universal gravitation at extremely low accelerations, 190 00:06:27,840 --> 00:06:30,240 which are typical in the outer regions of galaxies. 191 00:06:30,240 --> 00:06:32,240 So instead of needing this halo of dark matter 192 00:06:32,240 --> 00:06:34,040 to keep those stars speeding along, 193 00:06:34,040 --> 00:06:36,800 gravity itself gets a boost in those outer regions. 194 00:06:36,800 --> 00:06:37,640 Exactly. 195 00:06:37,640 --> 00:06:39,720 And some of these MOND theories even 196 00:06:39,720 --> 00:06:42,480 try to fit within the framework of general relativity, 197 00:06:42,480 --> 00:06:44,700 offering an alternative interpretation 198 00:06:44,700 --> 00:06:46,640 of the gravitational lensing observations 199 00:06:46,640 --> 00:06:48,000 we discussed earlier. 200 00:06:48,000 --> 00:06:49,920 It's fascinating how the same set of clues 201 00:06:49,920 --> 00:06:52,240 can lead to such radically different explanations. 202 00:06:52,240 --> 00:06:54,200 It seems we have a classic scientific showdown 203 00:06:54,200 --> 00:06:56,960 brewing new particles versus new physics. 204 00:06:56,960 --> 00:06:59,320 How do scientists go about testing these competing 205 00:06:59,320 --> 00:07:00,040 theories? 206 00:07:00,040 --> 00:07:02,560 It's a multifaceted battle fought on many fronts, 207 00:07:02,560 --> 00:07:04,440 from deep underground laboratories 208 00:07:04,440 --> 00:07:07,200 to space-based observatories. 209 00:07:07,200 --> 00:07:09,120 One approach is direct detection, where 210 00:07:09,120 --> 00:07:12,080 scientists are literally waiting for a dark matter particle 211 00:07:12,080 --> 00:07:13,680 to bump into a detector. 212 00:07:13,680 --> 00:07:16,280 It's like setting a cosmic trap and hoping something invisible 213 00:07:16,280 --> 00:07:17,280 stumbles into it. 214 00:07:17,280 --> 00:07:18,840 In essence, yes. 215 00:07:18,840 --> 00:07:21,720 These detectors are often located deep underground 216 00:07:21,720 --> 00:07:24,960 to shield them from cosmic rays and other background noise. 217 00:07:24,960 --> 00:07:26,820 They use incredibly sensitive instruments 218 00:07:26,820 --> 00:07:30,080 to detect the faintest recoil or energy deposit that 219 00:07:30,080 --> 00:07:33,520 would occur if a wimp or another weakly interacting particle 220 00:07:33,520 --> 00:07:35,880 collided with an atom in the detector. 221 00:07:35,880 --> 00:07:38,560 What about those lighter, even more elusive candidates, 222 00:07:38,560 --> 00:07:41,400 like axions and sterile neutrinos? 223 00:07:41,400 --> 00:07:43,200 How do scientists try to catch those? 224 00:07:43,200 --> 00:07:46,160 For those we often rely on indirect detection. 225 00:07:46,160 --> 00:07:48,240 Instead of trying to catch the particles themselves, 226 00:07:48,240 --> 00:07:50,560 we look for telltale signs of their presence. 227 00:07:50,560 --> 00:07:52,200 For example, if dark matter particles 228 00:07:52,200 --> 00:07:54,280 can annihilate each other, this process 229 00:07:54,280 --> 00:07:57,440 could produce other particles, like gamma rays or neutrinos, 230 00:07:57,440 --> 00:07:59,640 that we can detect with specialized telescopes. 231 00:07:59,640 --> 00:08:01,800 So it's like searching for the footprints left behind 232 00:08:01,800 --> 00:08:03,680 by a creature we can't see directly. 233 00:08:03,680 --> 00:08:05,240 That's a great analogy. 234 00:08:05,240 --> 00:08:08,600 Scientists are looking for specific patterns or excesses 235 00:08:08,600 --> 00:08:10,280 in these cosmic signals that could 236 00:08:10,280 --> 00:08:12,800 betray the presence of dark matter interactions. 237 00:08:12,800 --> 00:08:15,520 We've talked about detectors, hidden deep underground 238 00:08:15,520 --> 00:08:18,520 telescopes, scanning the skies. 239 00:08:18,520 --> 00:08:21,480 What other tools do scientists have in their arsenal 240 00:08:21,480 --> 00:08:23,280 to probe this mystery? 241 00:08:23,280 --> 00:08:25,680 Particle accelerators like the Large Hadron Collider 242 00:08:25,680 --> 00:08:27,120 play a crucial role. 243 00:08:27,120 --> 00:08:30,040 These massive machines smash protons together 244 00:08:30,040 --> 00:08:32,000 at incredibly high energies, creating 245 00:08:32,000 --> 00:08:34,000 a shower of new particles. 246 00:08:34,000 --> 00:08:35,760 The hope is that some of these collisions 247 00:08:35,760 --> 00:08:37,520 might produce dark matter particles, 248 00:08:37,520 --> 00:08:40,080 allowing us to study their properties directly. 249 00:08:40,080 --> 00:08:42,360 So if we can create dark matter in the lab, 250 00:08:42,360 --> 00:08:44,880 it could finally lift the veil on its true nature. 251 00:08:44,880 --> 00:08:46,040 Exactly. 252 00:08:46,040 --> 00:08:48,120 And there are even more ambitious experiments 253 00:08:48,120 --> 00:08:50,680 on the horizon, like next generation detectors that 254 00:08:50,680 --> 00:08:54,200 utilize quantum technology to achieve unprecedented levels 255 00:08:54,200 --> 00:08:55,640 of sensitivity. 256 00:08:55,640 --> 00:08:56,960 These detectors could potentially 257 00:08:56,960 --> 00:08:59,320 detect even the faintest whispers of dark matter 258 00:08:59,320 --> 00:09:00,560 interactions. 259 00:09:00,560 --> 00:09:03,280 It sounds like the field is buzzing with activity. 260 00:09:03,280 --> 00:09:05,200 But even with all these efforts, dark matter 261 00:09:05,200 --> 00:09:06,520 remains a stubborn puzzle. 262 00:09:06,520 --> 00:09:08,120 What are some of the biggest challenges 263 00:09:08,120 --> 00:09:11,120 that researchers face in cracking this cosmic case? 264 00:09:11,120 --> 00:09:13,800 Well, one of the biggest hurdles is the very nature of dark matter 265 00:09:13,800 --> 00:09:14,960 itself. 266 00:09:14,960 --> 00:09:17,560 It's incredibly elusive, interacting so weakly 267 00:09:17,560 --> 00:09:20,280 with ordinary matter and light that it's incredibly 268 00:09:20,280 --> 00:09:21,920 difficult to detect directly. 269 00:09:21,920 --> 00:09:22,440 Yeah. 270 00:09:22,440 --> 00:09:25,080 We're essentially trying to catch a shadow. 271 00:09:25,080 --> 00:09:27,800 And then there's the challenge of differentiating the signal 272 00:09:27,800 --> 00:09:29,280 from the noise. 273 00:09:29,280 --> 00:09:30,280 What do you mean by that? 274 00:09:30,280 --> 00:09:32,560 The universe is a noisy place. 275 00:09:32,560 --> 00:09:36,880 Cosmic rays, radioactive decay, even the faintest vibrations 276 00:09:36,880 --> 00:09:39,520 on the Earth's crust can create signals 277 00:09:39,520 --> 00:09:42,600 that mimic those we're looking for from dark matter. 278 00:09:42,600 --> 00:09:44,800 So scientists have to go to great lengths 279 00:09:44,800 --> 00:09:47,480 to shield their experiments and analyze their data 280 00:09:47,480 --> 00:09:51,080 meticulously to tease out any genuine signs of dark matter. 281 00:09:51,080 --> 00:09:52,680 So it's like trying to hear a whisper 282 00:09:52,680 --> 00:09:53,920 in the middle of a hurricane. 283 00:09:53,920 --> 00:09:55,400 A very apt analogy. 284 00:09:55,400 --> 00:09:57,240 And to make things even more challenging, 285 00:09:57,240 --> 00:09:59,760 there's the sheer diversity of possible candidates 286 00:09:59,760 --> 00:10:00,760 and theories. 287 00:10:00,760 --> 00:10:02,920 It's like having a thousand piece puzzle where you're not 288 00:10:02,920 --> 00:10:05,160 even sure what the final image is supposed to be. 289 00:10:05,160 --> 00:10:06,920 That sounds incredibly daunting. 290 00:10:06,920 --> 00:10:09,160 It makes you wonder if all this effort is worth it. 291 00:10:09,160 --> 00:10:11,200 Why are we so obsessed with understanding something we 292 00:10:11,200 --> 00:10:12,760 can't even see or touch? 293 00:10:12,760 --> 00:10:14,320 What's the big deal with dark matter? 294 00:10:14,320 --> 00:10:16,080 That's a question that often comes up. 295 00:10:16,080 --> 00:10:20,080 And the answer lies in its profound implications. 296 00:10:20,080 --> 00:10:23,240 Dark matter isn't just some esoteric curiosity. 297 00:10:23,240 --> 00:10:26,720 It's the cosmic scaffolding upon which the entire universe 298 00:10:26,720 --> 00:10:27,360 is built. 299 00:10:27,360 --> 00:10:28,820 Can you elaborate on that? 300 00:10:28,820 --> 00:10:32,360 How does something unseen have such a monumental impact? 301 00:10:32,360 --> 00:10:35,440 Imagine the early universe, a swirling soup 302 00:10:35,440 --> 00:10:37,240 of hot, dense gas. 303 00:10:37,240 --> 00:10:41,000 Now imagine trying to form galaxies from that chaos. 304 00:10:41,000 --> 00:10:44,400 It's like trying to build a sandcastle on a windy beach. 305 00:10:44,400 --> 00:10:46,160 Gravity wants to pull matter together, 306 00:10:46,160 --> 00:10:47,720 but the expansion of the universe 307 00:10:47,720 --> 00:10:49,360 and the random motions of particles 308 00:10:49,360 --> 00:10:50,440 are working against it. 309 00:10:50,440 --> 00:10:51,880 There's a cosmic tug of war. 310 00:10:51,880 --> 00:10:52,840 Precisely. 311 00:10:52,840 --> 00:10:55,120 And this is where dark matter enters the stage. 312 00:10:55,120 --> 00:10:57,120 Because it interacts primarily through gravity, 313 00:10:57,120 --> 00:10:59,120 it's less affected by those other forces. 314 00:10:59,120 --> 00:11:00,800 It's like a cosmic anchor providing 315 00:11:00,800 --> 00:11:03,040 the extra gravitational pull needed 316 00:11:03,040 --> 00:11:04,960 to overcome those disruptive forces 317 00:11:04,960 --> 00:11:06,880 and allow matter to clump together, forming 318 00:11:06,880 --> 00:11:08,440 the seeds of future galaxies. 319 00:11:08,440 --> 00:11:11,060 So without dark matter's gravitational embrace, 320 00:11:11,060 --> 00:11:13,400 those early galaxies wouldn't have stood a chance. 321 00:11:13,400 --> 00:11:14,160 Exactly. 322 00:11:14,160 --> 00:11:15,960 They would have been torn apart before they 323 00:11:15,960 --> 00:11:17,360 could even begin to form. 324 00:11:17,360 --> 00:11:20,640 And this influence extends beyond the early universe. 325 00:11:20,640 --> 00:11:22,920 Dark matter continues to play a crucial role 326 00:11:22,920 --> 00:11:25,520 in the evolution and structure of galaxies today. 327 00:11:25,520 --> 00:11:26,200 Awesome. 328 00:11:26,200 --> 00:11:28,560 Galaxies rotate, and without enough mass, 329 00:11:28,560 --> 00:11:32,040 they would simply fly apart due to centrifugal force. 330 00:11:32,040 --> 00:11:34,760 But we observe that galaxies are rotating much faster 331 00:11:34,760 --> 00:11:37,200 than they should based on the visible matter alone. 332 00:11:37,200 --> 00:11:39,360 So dark matter provides the extra gravity 333 00:11:39,360 --> 00:11:41,080 to keep them from spinning themselves apart. 334 00:11:41,080 --> 00:11:41,800 Precisely. 335 00:11:41,800 --> 00:11:44,760 It acts like an invisible halo surrounding each galaxy, 336 00:11:44,760 --> 00:11:46,720 providing the gravitational force needed 337 00:11:46,720 --> 00:11:48,640 to keep everything in check. 338 00:11:48,640 --> 00:11:51,400 It's mind boggling to think about this unseen force 339 00:11:51,400 --> 00:11:55,120 orchestrating the cosmos on such a grand scale. 340 00:11:55,120 --> 00:11:57,080 But I'm curious, what are the implications for us 341 00:11:57,080 --> 00:11:58,400 here on Earth? 342 00:11:58,400 --> 00:12:00,960 Does dark matter have any direct impact on our lives? 343 00:12:00,960 --> 00:12:02,760 It's a fascinating question, and one 344 00:12:02,760 --> 00:12:04,720 that scientists are still exploring. 345 00:12:04,720 --> 00:12:06,760 While dark matter doesn't interact strongly 346 00:12:06,760 --> 00:12:08,920 with ordinary matter, there are subtle ways 347 00:12:08,920 --> 00:12:10,480 it could influence our planet. 348 00:12:10,480 --> 00:12:12,000 For example, some theories suggest 349 00:12:12,000 --> 00:12:14,080 that dark matter particles passing through Earth 350 00:12:14,080 --> 00:12:16,680 could occasionally interact with atoms potentially causing 351 00:12:16,680 --> 00:12:19,440 tiny temperature fluctuations or even triggering mutations 352 00:12:19,440 --> 00:12:20,320 in DNA. 353 00:12:20,320 --> 00:12:23,880 So dark matter could be playing a role in evolution. 354 00:12:23,880 --> 00:12:26,160 That's wild, but these interactions 355 00:12:26,160 --> 00:12:27,880 must be incredibly rare, right? 356 00:12:27,880 --> 00:12:29,640 Incredibly rare indeed. 357 00:12:29,640 --> 00:12:32,600 The effects, if any, would be extremely subtle and difficult 358 00:12:32,600 --> 00:12:33,560 to detect. 359 00:12:33,560 --> 00:12:35,760 But even if its impact on our daily lives 360 00:12:35,760 --> 00:12:38,200 is minimal understanding, dark matter 361 00:12:38,200 --> 00:12:41,400 is crucial for understanding the universe as a whole. 362 00:12:41,400 --> 00:12:43,920 It's a fundamental component of the cosmic web, 363 00:12:43,920 --> 00:12:46,200 the intricate network of galaxies, gas, 364 00:12:46,200 --> 00:12:48,300 and dark matter that makes up the large scale 365 00:12:48,300 --> 00:12:50,040 structure of the universe. 366 00:12:50,040 --> 00:12:52,040 It sounds like we're just scratching the surface 367 00:12:52,040 --> 00:12:53,280 of this cosmic enigma. 368 00:12:53,280 --> 00:12:56,040 What's next in the quest to understand dark matter? 369 00:12:56,040 --> 00:12:57,760 What exciting discoveries might be 370 00:12:57,760 --> 00:12:59,360 lurking just around the corner? 371 00:12:59,360 --> 00:13:01,440 Well, one avenue that holds a lot of promise 372 00:13:01,440 --> 00:13:03,800 is the development of even more sensitive dark matter 373 00:13:03,800 --> 00:13:04,920 detectors. 374 00:13:04,920 --> 00:13:07,040 For example, researchers are working on detectors 375 00:13:07,040 --> 00:13:10,840 that use liquid xenon or argon cooled to extremely low 376 00:13:10,840 --> 00:13:12,400 temperatures. 377 00:13:12,400 --> 00:13:15,400 The idea is that if a dark matter particle collides 378 00:13:15,400 --> 00:13:17,160 with an atom in these detectors, it 379 00:13:17,160 --> 00:13:19,920 would produce this tiny flash of light 380 00:13:19,920 --> 00:13:22,880 that can be picked up by these incredibly sensitive sensors. 381 00:13:22,880 --> 00:13:26,000 It's like waiting for a faint spark in a vast dark chamber. 382 00:13:26,000 --> 00:13:26,920 Exactly. 383 00:13:26,920 --> 00:13:28,940 And these next generation detectors 384 00:13:28,940 --> 00:13:31,440 are being designed to be even more sensitive than previous 385 00:13:31,440 --> 00:13:33,720 experiments, pushing the limits of our ability 386 00:13:33,720 --> 00:13:37,040 to detect those elusive whispers of dark matter. 387 00:13:37,040 --> 00:13:38,800 We've also talked about space telescopes. 388 00:13:38,800 --> 00:13:40,840 What role do they play in this cosmic hunt? 389 00:13:40,840 --> 00:13:43,680 Yeah, space telescopes offer a unique vantage point. 390 00:13:43,680 --> 00:13:45,720 They're above the Earth's atmosphere, 391 00:13:45,720 --> 00:13:47,720 which blocks many types of radiation, 392 00:13:47,720 --> 00:13:49,900 giving them a clear view of the cosmos. 393 00:13:49,900 --> 00:13:52,840 For example, the Fermi Gamma Ray Space Telescope 394 00:13:52,840 --> 00:13:55,800 is searching for signs of dark matter annihilation 395 00:13:55,800 --> 00:13:58,080 in the centers of galaxies where dark matter is thought 396 00:13:58,080 --> 00:13:59,560 to be most concentrated. 397 00:13:59,560 --> 00:14:01,800 So it's like having a cosmic spy satellite scanning 398 00:14:01,800 --> 00:14:03,080 the universe for clues. 399 00:14:03,080 --> 00:14:05,000 A very apt analogy. 400 00:14:05,000 --> 00:14:08,240 And there are other exciting space missions on the horizon. 401 00:14:08,240 --> 00:14:10,200 For example, the Euclid Space Telescope 402 00:14:10,200 --> 00:14:12,040 set to launch in the next few years 403 00:14:12,040 --> 00:14:15,040 will create a 3D map of the distribution of dark matter 404 00:14:15,040 --> 00:14:18,320 across the universe by observing how its gravity distorts 405 00:14:18,320 --> 00:14:20,400 the images of distant galaxies. 406 00:14:20,400 --> 00:14:23,200 It sounds like we're entering a golden age of dark matter 407 00:14:23,200 --> 00:14:27,520 exploration with new tools and techniques constantly 408 00:14:27,520 --> 00:14:28,680 being developed. 409 00:14:28,680 --> 00:14:32,080 But I'm curious, what would a definitive eureka moment 410 00:14:32,080 --> 00:14:34,160 look like in this field? 411 00:14:34,160 --> 00:14:35,880 How would we know for sure that we've finally 412 00:14:35,880 --> 00:14:37,600 cracked the code of dark matter? 413 00:14:37,600 --> 00:14:38,980 Well, there are a few different scenarios 414 00:14:38,980 --> 00:14:41,060 that would send shock waves through the scientific 415 00:14:41,060 --> 00:14:41,880 community. 416 00:14:41,880 --> 00:14:43,440 One would be the direct detection 417 00:14:43,440 --> 00:14:45,960 of a dark matter particle in one of these ultra-sensitive 418 00:14:45,960 --> 00:14:47,560 underground laboratories. 419 00:14:47,560 --> 00:14:49,760 If we can capture a wimp or an axion 420 00:14:49,760 --> 00:14:52,040 and study its properties, it would be a game changer. 421 00:14:52,040 --> 00:14:54,400 It would be like finally meeting the mysterious stranger 422 00:14:54,400 --> 00:14:55,920 we've been chasing for so long. 423 00:14:55,920 --> 00:14:57,080 Exactly. 424 00:14:57,080 --> 00:14:59,960 Another breakthrough could come from particle accelerators. 425 00:14:59,960 --> 00:15:02,960 If experiments at the Large Hadron Collider or future even 426 00:15:02,960 --> 00:15:05,620 more powerful colliders produce particles 427 00:15:05,620 --> 00:15:08,000 that match the predicted properties of dark matter, 428 00:15:08,000 --> 00:15:10,800 it would provide strong evidence for its existence. 429 00:15:10,800 --> 00:15:12,520 So we could create dark matter ourselves 430 00:15:12,520 --> 00:15:13,840 and study it up close. 431 00:15:13,840 --> 00:15:17,740 It's a possibility that has many physicists incredibly excited. 432 00:15:17,740 --> 00:15:19,440 And then there's the possibility of observing 433 00:15:19,440 --> 00:15:21,800 a completely unexpected phenomenon that 434 00:15:21,800 --> 00:15:24,880 can only be explained by the presence of dark matter. 435 00:15:24,880 --> 00:15:27,740 Like a cosmic smoking gun that points directly 436 00:15:27,740 --> 00:15:29,120 to dark matter's existence. 437 00:15:29,120 --> 00:15:29,960 Precisely. 438 00:15:29,960 --> 00:15:33,160 It could be a new type of astrophysical observation 439 00:15:33,160 --> 00:15:35,920 or an anomaly in particle physics experiments 440 00:15:35,920 --> 00:15:38,160 that defies our current understanding 441 00:15:38,160 --> 00:15:40,720 and forces us to rethink our models of the universe. 442 00:15:40,720 --> 00:15:42,400 It's incredible to think that we could be 443 00:15:42,400 --> 00:15:44,600 on the verge of such groundbreaking discoveries. 444 00:15:44,600 --> 00:15:47,160 It feels like we're standing on the precipice of a new era 445 00:15:47,160 --> 00:15:49,240 in our understanding of the universe. 446 00:15:49,240 --> 00:15:51,320 But I'm curious, what are some of the broader 447 00:15:51,320 --> 00:15:54,320 implications of solving the dark matter mystery? 448 00:15:54,320 --> 00:15:57,200 How would it change our view of the cosmos and our place in it? 449 00:15:57,200 --> 00:15:59,320 The implications are profound. 450 00:15:59,320 --> 00:16:01,920 If we can definitively identify dark matter, 451 00:16:01,920 --> 00:16:04,120 it would not only fill a major gap in our understanding 452 00:16:04,120 --> 00:16:07,120 of the universe, but also open up entirely new avenues 453 00:16:07,120 --> 00:16:08,320 of inquiry. 454 00:16:08,320 --> 00:16:10,180 For example, if dark matter interacts 455 00:16:10,180 --> 00:16:12,040 through forces other than gravity, 456 00:16:12,040 --> 00:16:13,520 it would point towards new physics 457 00:16:13,520 --> 00:16:15,800 beyond the standard model potentially 458 00:16:15,800 --> 00:16:17,920 leading to a revolution in our understanding 459 00:16:17,920 --> 00:16:18,760 of particle physics. 460 00:16:18,760 --> 00:16:20,440 So it could rewrite the textbooks 461 00:16:20,440 --> 00:16:22,600 on the fundamental building blocks of the universe. 462 00:16:22,600 --> 00:16:23,920 It certainly could. 463 00:16:23,920 --> 00:16:25,640 And understanding dark matter could also 464 00:16:25,640 --> 00:16:28,320 shed light on the evolution of the universe as a whole. 465 00:16:28,320 --> 00:16:31,600 It could help us understand how galaxies formed and evolved, 466 00:16:31,600 --> 00:16:34,520 how the cosmic web took shape, and perhaps even 467 00:16:34,520 --> 00:16:37,320 provide clues about the ultimate fate of the universe. 468 00:16:37,320 --> 00:16:40,120 It's a reminder that even the most invisible things can 469 00:16:40,120 --> 00:16:42,360 have the most profound impacts. 470 00:16:42,360 --> 00:16:45,700 But I'm also wondering, what if we never solve the mystery? 471 00:16:45,700 --> 00:16:48,060 What if dark matter remains elusive, 472 00:16:48,060 --> 00:16:50,760 a cosmic enigma that continues to taunt us? 473 00:16:50,760 --> 00:16:53,200 It's a possibility we have to consider. 474 00:16:53,200 --> 00:16:56,560 But even if we never definitively identify dark matter, 475 00:16:56,560 --> 00:16:59,120 the search itself is incredibly valuable. 476 00:16:59,120 --> 00:17:01,480 It's pushing the boundaries of science and technology, 477 00:17:01,480 --> 00:17:03,960 inspiring new generations of scientists, 478 00:17:03,960 --> 00:17:07,080 and forcing us to confront the limits of our knowledge. 479 00:17:07,080 --> 00:17:09,160 It's a humbling reminder that there's still so much 480 00:17:09,160 --> 00:17:11,200 we don't know about the universe, 481 00:17:11,200 --> 00:17:12,560 and that the journey of discovery 482 00:17:12,560 --> 00:17:14,960 is just as important as the destination. 483 00:17:14,960 --> 00:17:15,920 Absolutely. 484 00:17:15,920 --> 00:17:18,720 The pursuit of knowledge is what drives us forward. 485 00:17:18,720 --> 00:17:21,240 And who knows, perhaps the most profound discoveries 486 00:17:21,240 --> 00:17:23,400 are the ones we haven't even imagined yet. 487 00:17:23,400 --> 00:17:25,160 It's been an incredible journey exploring 488 00:17:25,160 --> 00:17:27,000 the enigmatic world of dark matter, 489 00:17:27,000 --> 00:17:30,880 from its elusive nature to its profound cosmic influence. 490 00:17:30,880 --> 00:17:32,920 Thanks for guiding us through this cosmic mystery. 491 00:17:32,920 --> 00:17:33,960 It's been my pleasure. 492 00:17:33,960 --> 00:17:36,000 And for those of you listening, if this deep dive 493 00:17:36,000 --> 00:17:39,000 into the world of dark matter has sparked your curiosity, 494 00:17:39,000 --> 00:17:41,120 I encourage you to delve deeper into the subject. 495 00:17:41,120 --> 00:17:44,040 There are countless resources available online in libraries 496 00:17:44,040 --> 00:17:46,000 and through science organizations. 497 00:17:46,000 --> 00:17:47,800 And who knows, maybe one of you listening 498 00:17:47,800 --> 00:17:50,000 will be the one to finally unlock the secrets 499 00:17:50,000 --> 00:17:51,680 of this cosmic enigma. 500 00:17:51,680 --> 00:17:54,160 And that wraps up our exploration of dark matter 501 00:17:54,160 --> 00:17:57,080 for this episode of Cosmos CinePod. 502 00:17:57,080 --> 00:17:59,920 Don't forget to follow and subscribe to Cosmos CinePod 503 00:17:59,920 --> 00:18:01,940 on your favorite podcast platform 504 00:18:01,940 --> 00:18:04,760 so you don't miss our next cosmic adventure. 505 00:18:04,760 --> 00:18:06,720 We release new episodes every week, 506 00:18:06,720 --> 00:18:08,800 exploring all sorts of fascinating topics 507 00:18:08,800 --> 00:18:10,280 in space and astronomy. 508 00:18:10,280 --> 00:18:11,920 And be sure to check out our YouTube channel 509 00:18:11,920 --> 00:18:15,120 for even more cosmic content, including stunning visuals, 510 00:18:15,120 --> 00:18:17,520 animations, and interviews with leading scientists. 511 00:18:17,520 --> 00:18:20,440 Until next time, keep looking up and keep wondering. 512 00:18:20,440 --> 00:18:42,800 The universe is full of mysteries waiting to be uncovered.