1 00:00:00,120 --> 00:00:03,319 Speaker 1: Imagine a small object, something you could just hold between 2 00:00:03,359 --> 00:00:06,599 your finger and thumb. Let's say a golf ball. Now 3 00:00:06,679 --> 00:00:09,519 try to imagine that that same golf ball weighs more 4 00:00:09,560 --> 00:00:10,720 than the entire planet Earth. 5 00:00:10,800 --> 00:00:13,000 Speaker 2: Yeah, it's already an impossible thought, right. 6 00:00:12,880 --> 00:00:15,359 Speaker 1: And not just a little more, but so dense, so 7 00:00:16,640 --> 00:00:19,640 gravitationally powerful, that if you brought it near our world, 8 00:00:19,719 --> 00:00:23,079 it would just consume it instantly. And what's left behind 9 00:00:23,160 --> 00:00:27,160 is just this sphere of influence, barely bigger than a line. 10 00:00:27,480 --> 00:00:29,120 I mean, it sounds like complete science fiction. 11 00:00:29,280 --> 00:00:29,719 Speaker 2: It does. 12 00:00:30,039 --> 00:00:32,479 Speaker 3: But you know the fact that this isn't just possible, 13 00:00:32,520 --> 00:00:35,159 but is actually an unavoidable outcome of the laws of nature. 14 00:00:35,240 --> 00:00:36,200 Speaker 2: Well, that tells you something. 15 00:00:36,399 --> 00:00:39,159 Speaker 3: It tells you just how unreliable our own senses really are. 16 00:00:39,159 --> 00:00:43,719 The universe it operates on scales and densities our brains 17 00:00:43,759 --> 00:00:46,159 never ever evolve to grasp. 18 00:00:46,560 --> 00:00:49,520 Speaker 1: Welcome to thrilling threads. We take a stack of dense, 19 00:00:49,600 --> 00:00:54,079 fascinating sources, articles, research, conversations, and we untangle them to 20 00:00:54,119 --> 00:00:57,000 give you the knowledge you need, fast and thorough. Our 21 00:00:57,039 --> 00:00:59,880 mission today is to pull insights from a conversation with 22 00:01:00,119 --> 00:01:04,200 a leading astrophysicist who really he challenges our most basic 23 00:01:04,280 --> 00:01:07,480 ideas about reality, about scale, and about our place in 24 00:01:07,519 --> 00:01:10,120 the cosmos. We are going way beyond what our five 25 00:01:10,159 --> 00:01:11,040 senses can tell us. 26 00:01:11,079 --> 00:01:12,640 Speaker 2: And that's the whole point of the source material. 27 00:01:12,680 --> 00:01:16,200 Speaker 3: Really, the central idea is that human perception is, to 28 00:01:16,239 --> 00:01:19,519 put it, mildly, wildly insufficient for understanding what's real. 29 00:01:19,680 --> 00:01:20,760 Speaker 1: Insufficient. I like that. 30 00:01:21,000 --> 00:01:21,680 Speaker 2: Think about it. 31 00:01:22,200 --> 00:01:25,200 Speaker 3: Our eyes they see this tiny, tiny sliver of the 32 00:01:25,239 --> 00:01:29,439 electromagnetic spectrum. Our ears pick up a narrow band of vibrations. 33 00:01:29,760 --> 00:01:33,239 Science only moves forward when we stop trusting our what 34 00:01:33,280 --> 00:01:35,959 the source calls are error prone biology. 35 00:01:35,480 --> 00:01:36,680 Speaker 1: And start trusting the machine. 36 00:01:36,760 --> 00:01:37,280 Speaker 2: Exactly. 37 00:01:37,319 --> 00:01:40,560 Speaker 3: We have to use machine driven methods, telescopes, particle accelerators, 38 00:01:40,560 --> 00:01:43,239 all of it to get an objective report on reality. 39 00:01:43,680 --> 00:01:46,280 And that objectivity that's the only way we ever arrived 40 00:01:46,319 --> 00:01:49,000 at the frankly terrifying truth of the black hole. 41 00:01:49,519 --> 00:01:53,959 Speaker 1: Okay, so let's get into it, this massive concept the 42 00:01:54,000 --> 00:01:56,879 black hole. We started with that crazy golf ball analogy, 43 00:01:56,920 --> 00:01:58,799 But to really build up to that, we need to 44 00:01:58,799 --> 00:02:02,400 start with something a bit simpler, right, something like escape velocity. 45 00:02:02,599 --> 00:02:03,120 Speaker 2: Exactly. 46 00:02:03,239 --> 00:02:06,000 Speaker 3: Escape velocity is just the specific speed you need to 47 00:02:06,000 --> 00:02:09,039 go to well to break free from the gravity of 48 00:02:09,080 --> 00:02:10,800 a planet or a star and never. 49 00:02:10,639 --> 00:02:12,280 Speaker 1: Come back like a rocket launch. 50 00:02:12,479 --> 00:02:15,759 Speaker 3: Perfect example for Earth. That speed is about seven miles 51 00:02:15,800 --> 00:02:18,800 per second. That's roughly twenty five thousand miles per hour. 52 00:02:18,840 --> 00:02:21,159 Speaker 1: Seven miles per second. You know, when you say it 53 00:02:21,199 --> 00:02:23,039 like that, it makes that old saying what goes up 54 00:02:23,120 --> 00:02:25,680 must come down. It's not actually true, is it. 55 00:02:25,800 --> 00:02:28,199 Speaker 2: Hey, No, it's true for a baseball. 56 00:02:28,240 --> 00:02:30,520 Speaker 3: Sure, But if you have the power to get something 57 00:02:30,560 --> 00:02:33,199 moving at seven miles per second, it is gone. 58 00:02:33,319 --> 00:02:35,159 Speaker 2: It has escaped Earth grasp for good. 59 00:02:35,240 --> 00:02:37,319 Speaker 1: Okay, so let's scale that up. This is the thought. 60 00:02:37,080 --> 00:02:39,120 Speaker 3: Experiment, right, This is the thought experiment that leads us 61 00:02:39,120 --> 00:02:42,479 straight to a black hole. Imagine if Earth had more mass, 62 00:02:42,960 --> 00:02:44,919 its gravity would be stronger. 63 00:02:44,680 --> 00:02:46,159 Speaker 1: Right, it would be harder to get. 64 00:02:46,039 --> 00:02:47,199 Speaker 2: Away, exactly. 65 00:02:47,240 --> 00:02:49,719 Speaker 3: The gravitational well gets deeper, so you'd need a higher 66 00:02:49,800 --> 00:02:52,759 escape velocity to climb out of it. You're seven miles 67 00:02:52,759 --> 00:02:56,199 per second becomes eight thn ten than one hundred. 68 00:02:56,639 --> 00:02:58,560 Speaker 1: So we just keep packing more and more mass into 69 00:02:58,599 --> 00:03:02,319 the same space. Gravity get stronger, and the escape velocity 70 00:03:02,360 --> 00:03:03,039 just keeps climbing. 71 00:03:03,120 --> 00:03:04,159 Speaker 2: It just keeps going up. 72 00:03:04,319 --> 00:03:07,199 Speaker 3: But here's where it gets really interesting, because eventually you 73 00:03:07,280 --> 00:03:09,439 hit a wall, you hit the cosmic speed limit. 74 00:03:09,240 --> 00:03:11,000 Speaker 1: The absolute fastest anything. 75 00:03:10,680 --> 00:03:11,879 Speaker 2: Can go, the speed of light. 76 00:03:12,240 --> 00:03:15,159 Speaker 3: It's about one hundred and eighty six thousand miles per second, 77 00:03:15,719 --> 00:03:18,560 and once the escape velocity needed to leave an object's 78 00:03:18,560 --> 00:03:22,159 surface hits that number, you've reached the threshold. 79 00:03:22,240 --> 00:03:24,240 Speaker 1: Because nothing can go faster than light. 80 00:03:24,479 --> 00:03:28,080 Speaker 3: Nothing, it's an absolute constant of nature. So if even 81 00:03:28,159 --> 00:03:32,479 light itself cannot escape that gravitational pole, then absolutely nothing 82 00:03:32,520 --> 00:03:35,159 else can, not matter, not energy, nothing. 83 00:03:35,400 --> 00:03:36,120 Speaker 2: It's a trap. 84 00:03:36,240 --> 00:03:38,280 Speaker 1: And that's it. That's the definition of a black hole, 85 00:03:38,639 --> 00:03:40,360 the point where even light can't get out. 86 00:03:40,560 --> 00:03:43,800 Speaker 3: That's the fundamental definition. Yes, and it's not a flat, 87 00:03:43,840 --> 00:03:46,120 two dimensional hole. You have to remember, it's a three 88 00:03:46,120 --> 00:03:49,639 dimensional hole in the fabric of space time itself. No 89 00:03:49,719 --> 00:03:52,560 matter which direction you approach it from, you're caught. 90 00:03:52,759 --> 00:03:56,400 Speaker 1: It brings us back to that golf ball, that density paradox. 91 00:03:56,680 --> 00:03:59,759 Speaker 3: It's a mind bender, isn't it. The source details that 92 00:03:59,800 --> 00:04:01,960 for a black hole to have the mass of our 93 00:04:02,120 --> 00:04:05,199 entire Earth, all that matter would have to be crushed 94 00:04:05,240 --> 00:04:07,400 down into a volume the size of a golf. 95 00:04:07,199 --> 00:04:10,280 Speaker 1: Ball, and the boundary the point of no return. 96 00:04:10,240 --> 00:04:12,400 Speaker 2: The event horizon. That would be a sphere just a 97 00:04:12,439 --> 00:04:13,520 little bit bigger than a lime. 98 00:04:13,680 --> 00:04:15,400 Speaker 1: That's the part I just can't get my head around. 99 00:04:15,599 --> 00:04:18,759 You take our entire planet eight thousand miles across and 100 00:04:18,800 --> 00:04:21,079 you shrink it to a lime. Where does all the 101 00:04:22,079 --> 00:04:24,920 stuff go? It can't just vanish, It doesn't. 102 00:04:24,959 --> 00:04:28,360 Speaker 3: And this is a really important distinction. That line sized sphere, 103 00:04:28,360 --> 00:04:31,600 that's just the event horizon. It's the boundary line the 104 00:04:31,639 --> 00:04:34,519 gravitational agg right, all the actual mass of the Earth, 105 00:04:34,560 --> 00:04:37,199 every bit of it, has been compressed down inside that 106 00:04:37,279 --> 00:04:42,319 boundary to a single, infinitely dense point at the very 107 00:04:42,399 --> 00:04:46,480 center the singularity. A singularity a point with zero volume 108 00:04:46,519 --> 00:04:50,000 but all the mass exactly. It's a point where our 109 00:04:50,079 --> 00:04:53,279 current laws of physics just break down. We can't really 110 00:04:53,319 --> 00:04:56,120 describe it. So the mass is definitely still in there, 111 00:04:56,160 --> 00:04:59,879 it's just compacted into a space we literally can't comprehend. 112 00:05:00,160 --> 00:05:03,360 Speaker 1: That's terrifying. But it also leads to this really crucial 113 00:05:03,399 --> 00:05:06,959 point that you know movies always get wrong. Black holes 114 00:05:07,000 --> 00:05:10,439 are not giant cosmic vacuum cleaners, are They not? 115 00:05:10,600 --> 00:05:13,040 Speaker 3: At all? That is such a critical thing to understand. 116 00:05:13,439 --> 00:05:16,439 The gravity you feel from an object depends on its mass, 117 00:05:16,519 --> 00:05:19,160 not its density. As long as you're you know, a 118 00:05:19,199 --> 00:05:20,199 safe distance away. 119 00:05:20,279 --> 00:05:22,160 Speaker 1: So the gravity is the same whether it's a star 120 00:05:22,360 --> 00:05:23,680 or a tiny black hole, as. 121 00:05:23,600 --> 00:05:24,639 Speaker 2: Long as the mass is the same. 122 00:05:24,720 --> 00:05:28,800 Speaker 3: Yes, The source gives this perfect unsettling example. If our 123 00:05:28,920 --> 00:05:31,839 sun right now just magically turned into a black hole, 124 00:05:32,000 --> 00:05:34,079 oh wow, we wouldn't fly into it. Earth would just 125 00:05:34,079 --> 00:05:36,839 continue orbiting it at the exact same distance, feeling the 126 00:05:36,920 --> 00:05:40,360 exact same gravitational pull. Nothing would change gravitationally. 127 00:05:40,480 --> 00:05:42,920 Speaker 1: We'd freeze, obviously, but we wouldn't get sucked in. 128 00:05:43,079 --> 00:05:45,639 Speaker 3: You'd freeze, but you'd be in a stable orbit. The 129 00:05:45,759 --> 00:05:48,319 danger is only if you get too close and cross 130 00:05:48,399 --> 00:05:50,000 that now tiny event horizon. 131 00:05:50,279 --> 00:05:53,480 Speaker 1: Okay, so if they're invisible light traps, how on Earth 132 00:05:53,480 --> 00:05:55,120 do we know they're real? We can't see them. 133 00:05:55,240 --> 00:05:59,000 Speaker 3: This is where modern astrophysics just completely triumphs over our 134 00:05:59,360 --> 00:06:00,839 you know, our naked eyes. 135 00:06:01,720 --> 00:06:05,000 Speaker 2: We have a few key methods. The first one is cure. 136 00:06:04,800 --> 00:06:06,519 Speaker 1: Einstein general relativity. 137 00:06:06,639 --> 00:06:07,519 Speaker 2: General relativity. 138 00:06:07,560 --> 00:06:10,120 Speaker 3: It tells us that gravity isn't a force, it's a 139 00:06:10,160 --> 00:06:14,199 curvature in the fabric of space time. Massive objects warp 140 00:06:14,319 --> 00:06:15,360 the space around them. 141 00:06:15,480 --> 00:06:17,160 Speaker 1: So we don't look at the black hole. We look 142 00:06:17,199 --> 00:06:20,879 at what's happening around it, or even behind it exactly. 143 00:06:21,360 --> 00:06:24,600 Speaker 3: We look deep into the cosmos at galaxies that are 144 00:06:24,720 --> 00:06:28,480 way way behind a suspected black hole. The black hole's 145 00:06:28,519 --> 00:06:32,439 immense gravity acts like a lens, a cosmic magnifying glass, 146 00:06:32,439 --> 00:06:35,639 a gravitational lens, a gravitational lens yes, and when the 147 00:06:35,759 --> 00:06:39,079 light from that background galaxy passes through this warped space 148 00:06:39,160 --> 00:06:41,160 on its way to us, the light gets bent. 149 00:06:41,319 --> 00:06:42,160 Speaker 1: So what does that look like? 150 00:06:42,199 --> 00:06:45,240 Speaker 3: In our telescopes we see the distant galaxy shape get 151 00:06:45,279 --> 00:06:49,120 completely distorted. It gets stretched, smeared out into arcs. Sometimes 152 00:06:49,120 --> 00:06:51,639 you even see multiple images of the same galaxy. 153 00:06:51,319 --> 00:06:52,800 Speaker 1: IEP Looking through a warped piece of. 154 00:06:52,720 --> 00:06:56,920 Speaker 3: Glass precisely and in the most perfect alignments, you can 155 00:06:56,959 --> 00:07:01,079 get what's called an Einstein ring. Out of distortion tells 156 00:07:01,160 --> 00:07:03,839 us exactly how much mass is in the foreground, even 157 00:07:03,839 --> 00:07:07,040 though we can't see it. It's undeniable proof that something 158 00:07:07,199 --> 00:07:12,240 incredibly massive is sitting there bending space exactly as Einstein predicted. 159 00:07:12,639 --> 00:07:15,240 Speaker 1: That's incredible. It's like seeing the wind by watching the 160 00:07:15,240 --> 00:07:17,519 trees bend. What's the second method? 161 00:07:17,920 --> 00:07:20,680 Speaker 3: The second way involves something really common in the universe, 162 00:07:21,519 --> 00:07:25,319 binary star systems. Most stars you see in the sky 163 00:07:25,519 --> 00:07:28,600 aren't alone like our sun. They're locked in a gravitational 164 00:07:28,720 --> 00:07:30,160 dance with a companion. 165 00:07:29,759 --> 00:07:32,240 Speaker 1: Two stars orbiting each other or more. 166 00:07:32,680 --> 00:07:35,079 Speaker 3: And when one of those stars is massive enough, it 167 00:07:35,120 --> 00:07:37,279 can end its life and collapse into a black hole, 168 00:07:37,600 --> 00:07:39,439 but its companion star is still there. 169 00:07:39,480 --> 00:07:42,040 Speaker 1: So you have a normal star orbiting nothing. 170 00:07:42,199 --> 00:07:45,639 Speaker 3: Orbiting an invisible partner. And as that remaining star gets older, 171 00:07:45,680 --> 00:07:48,199 it starts to expand, it swells up, and its outer 172 00:07:48,279 --> 00:07:50,439 layers of gas can get close enough to be pulled 173 00:07:50,439 --> 00:07:52,040 away by the black hole's gravity. 174 00:07:52,160 --> 00:07:54,519 Speaker 1: And that material, I'm guessing it doesn't just fall straight in. 175 00:07:54,959 --> 00:07:59,199 Speaker 3: No, because of angular momentum, it spirals in. It forms 176 00:07:59,240 --> 00:08:02,879 this incredible violent structure called an accretion disc. It's like 177 00:08:02,920 --> 00:08:07,439 a giant, terrifying whirlpool of plasma swirling around the event 178 00:08:07,480 --> 00:08:11,519 horizon and then must get hot, unimaginably hot. The material 179 00:08:11,560 --> 00:08:14,079 in this disc is moving at a huge fraction of 180 00:08:14,120 --> 00:08:17,519 the speed of light. The friction, the magnetic fields, the 181 00:08:17,519 --> 00:08:21,240 gravitational shear, it all converts that energy into heat. 182 00:08:21,399 --> 00:08:22,240 Speaker 1: How hot are we talking? 183 00:08:22,560 --> 00:08:26,279 Speaker 3: Millions of degrees and something that hot radiates energy, but 184 00:08:26,399 --> 00:08:29,920 not as visible light. It shines brightly in high energy 185 00:08:29,920 --> 00:08:32,840 wavelengths like X rays and ultraviolet light. 186 00:08:32,799 --> 00:08:35,200 Speaker 1: AH, which is invisible to us but not to. 187 00:08:35,120 --> 00:08:36,639 Speaker 2: Our space telescope exactly. 188 00:08:36,679 --> 00:08:38,840 Speaker 3: We have X ray and UV telescopes in orbit that 189 00:08:38,879 --> 00:08:41,559 are designed specifically to see these things. We can see 190 00:08:41,600 --> 00:08:43,919 the X ray pulses, we can measure the spectrum of light, 191 00:08:44,159 --> 00:08:46,360 and by watching the orbit of the visible star, we 192 00:08:46,399 --> 00:08:48,720 can calculate the mass of its invisible partner. 193 00:08:48,799 --> 00:08:50,399 Speaker 1: And if that mass is too big to be a 194 00:08:50,440 --> 00:08:52,960 regular star or a neutron star, if. 195 00:08:52,879 --> 00:08:55,080 Speaker 3: It's over about three times the mass of our Sun, 196 00:08:55,120 --> 00:08:56,519 there's only one thing it can be. 197 00:08:56,679 --> 00:08:59,360 Speaker 2: It has to be a black hole. And we've found 198 00:08:59,639 --> 00:09:03,000 does and dozens of these systems. We're literally watching black 199 00:09:03,039 --> 00:09:03,679 holes feed. 200 00:09:03,960 --> 00:09:06,120 Speaker 1: Wow. Okay, so how do they form in the first place? 201 00:09:06,159 --> 00:09:07,559 What creates one of these things? 202 00:09:07,639 --> 00:09:10,679 Speaker 3: It's all about the death of the most massive stars. 203 00:09:10,840 --> 00:09:13,279 Star is much much bigger than our Sun. 204 00:09:13,559 --> 00:09:15,200 Speaker 1: So not every star becomes a black hole. 205 00:09:15,279 --> 00:09:16,399 Speaker 2: Oh no, most don't. 206 00:09:16,399 --> 00:09:19,039 Speaker 3: At the end of its life, a massive star runs 207 00:09:19,039 --> 00:09:22,120 out of fuel and its core collapses. This triggers a 208 00:09:22,240 --> 00:09:28,039 huge explosion, a supernova. But if the star is truly enormous, 209 00:09:28,679 --> 00:09:31,879 maybe twenty times the mass of our Sun or more. 210 00:09:31,759 --> 00:09:33,240 Speaker 1: The gravity is just too strong. 211 00:09:33,360 --> 00:09:36,080 Speaker 3: The inward pull of gravity is so overwhelming that the 212 00:09:36,120 --> 00:09:40,639 outward explosion just fails. The energy of the supernova isn't 213 00:09:40,720 --> 00:09:41,919 enough to escape. 214 00:09:41,600 --> 00:09:44,120 Speaker 1: So instead of blowing itself apart, it crushes itself. 215 00:09:44,159 --> 00:09:47,320 Speaker 3: The star implodes, the explosion is snuffed out by its 216 00:09:47,320 --> 00:09:50,679 own gravity, and the entire core collapses down on itself, 217 00:09:50,720 --> 00:09:52,440 all the way down to a singularity. 218 00:09:52,679 --> 00:09:54,639 Speaker 2: It's gravity winning the final. 219 00:09:54,399 --> 00:09:56,679 Speaker 1: Battle, and the Source points out that it's actually good 220 00:09:56,720 --> 00:09:57,960 thing that not all stars do this. 221 00:09:58,240 --> 00:10:01,879 Speaker 3: It's vital for our existence. The stars that do succeed 222 00:10:01,960 --> 00:10:05,080 in exploding as supernovae are the ones that spread all 223 00:10:05,120 --> 00:10:07,600 the heavy elements they created in their cores out into 224 00:10:07,600 --> 00:10:11,240 the galaxy. Carbon, oxygen, iron, all the building blocks of 225 00:10:11,279 --> 00:10:15,200 planets and people. Those explosions enrich the gas clouds that 226 00:10:15,320 --> 00:10:19,000 form the next generation of solar systems. If every big 227 00:10:19,080 --> 00:10:22,240 star just collapse into a black hole, the universe would 228 00:10:22,279 --> 00:10:24,200 be mostly hydrogen and helium. 229 00:10:24,679 --> 00:10:26,639 Speaker 2: Life as we know it would be impossible. 230 00:10:27,399 --> 00:10:31,600 Speaker 3: We are quite literally made of the ashes of successful supernovae. 231 00:10:31,639 --> 00:10:34,279 Speaker 1: That is just an incredible connection, and it brings us 232 00:10:34,320 --> 00:10:36,600 right back home to our own star. The Source calls 233 00:10:36,639 --> 00:10:39,080 our sun wimpy, which is kind of reassuring. 234 00:10:39,240 --> 00:10:42,159 Speaker 3: Yeah, yes, in the black hole department, it's definitely a wimp. 235 00:10:42,240 --> 00:10:44,720 It doesn't have nearly enough mass. But you know, that 236 00:10:44,720 --> 00:10:47,039 doesn't mean it won't eventually kill us. It'll just do 237 00:10:47,120 --> 00:10:47,919 it in a different. 238 00:10:47,679 --> 00:10:50,120 Speaker 1: Way by expanding into a red giant. Right, It'll swell 239 00:10:50,200 --> 00:10:51,360 up and swallow the inner planet. 240 00:10:51,600 --> 00:10:53,960 Speaker 3: That's the endgame, yes, But before we get to that, 241 00:10:54,039 --> 00:10:55,200 let's talk about the timeline. 242 00:10:55,240 --> 00:10:56,679 Speaker 2: How long does the Sun have left? 243 00:10:56,960 --> 00:10:59,600 Speaker 1: The consensus I think is about another five billion years, 244 00:11:00,200 --> 00:11:02,159 which is a number so big it's hard to even 245 00:11:02,320 --> 00:11:03,440 think about. It is. 246 00:11:03,639 --> 00:11:06,000 Speaker 2: It's longer than the Earth has even existed so far. 247 00:11:06,159 --> 00:11:08,919 Speaker 3: But the amazing thing is we know that number with 248 00:11:09,000 --> 00:11:10,960 a pretty high degree of certainty. 249 00:11:11,399 --> 00:11:13,080 Speaker 1: I mean, it's not like we can stick a dipstick 250 00:11:13,120 --> 00:11:14,759 in the Sun and check the fuel level. 251 00:11:15,039 --> 00:11:15,720 Speaker 2: No, we can't. 252 00:11:15,759 --> 00:11:18,519 Speaker 3: This is really one of the great triumphs of twentieth 253 00:11:18,559 --> 00:11:19,799 century astrophysics. 254 00:11:19,840 --> 00:11:21,000 Speaker 2: It's a comparative method. 255 00:11:21,600 --> 00:11:24,480 Speaker 3: First, we identify our stars type it's a G type 256 00:11:24,559 --> 00:11:25,159 yellow dwarf. 257 00:11:25,279 --> 00:11:25,600 Speaker 1: Okay. 258 00:11:25,960 --> 00:11:28,799 Speaker 3: Then we look out across the universe. We find huge 259 00:11:29,000 --> 00:11:32,519 clusters of stars, thousands of them that all formed at 260 00:11:32,519 --> 00:11:35,360 the same time. And within those clusters we see stars 261 00:11:35,440 --> 00:11:38,039 like our Sun, but at every different stage of their 262 00:11:38,080 --> 00:11:38,639 life cycle. 263 00:11:38,799 --> 00:11:42,720 Speaker 1: So you find baby yellow dwarfs, teenage ones, middle aged ones, 264 00:11:42,720 --> 00:11:43,799 and dying ones. 265 00:11:43,559 --> 00:11:45,679 Speaker 3: Exactly, and we can plot them all in a chart 266 00:11:45,919 --> 00:11:48,360 based on their brightness and their temperature. It's called the 267 00:11:48,440 --> 00:11:51,600 hurt Sprung Russell diagram or the HR diagram. 268 00:11:51,159 --> 00:11:53,480 Speaker 1: And this diagram shows the whole life story of a star. 269 00:11:53,879 --> 00:11:55,559 Speaker 2: It's a map of stellar evolution. 270 00:11:56,440 --> 00:11:58,879 Speaker 3: And by finding where our own Sun fits on that 271 00:11:59,039 --> 00:12:01,919 universal map, we can tell exactly how far along it 272 00:12:01,960 --> 00:12:04,679 is in its life. The data show is it's right 273 00:12:04,720 --> 00:12:09,039 in the middle, about halfway through its stable hydrogen burning phase. 274 00:12:09,120 --> 00:12:10,639 Speaker 1: And we have a way to double check that, don't 275 00:12:10,639 --> 00:12:11,840 we something right here at home? 276 00:12:11,879 --> 00:12:12,240 Speaker 2: We do? 277 00:12:12,320 --> 00:12:15,720 Speaker 3: We cross validated with geology. We can use things like 278 00:12:15,879 --> 00:12:19,480 radiometric dating of meteorites and rocks to get a very 279 00:12:19,519 --> 00:12:22,159 precise age for the Earth itself. 280 00:12:21,720 --> 00:12:24,039 Speaker 1: Which is about four and a half billion years right. 281 00:12:24,440 --> 00:12:27,039 Speaker 3: And since the Earth and the Sun formed together out 282 00:12:27,080 --> 00:12:29,960 of the same cloud of gas and dust, their ages 283 00:12:30,039 --> 00:12:32,279 have to match. The fact that the age of the 284 00:12:32,320 --> 00:12:35,320 Earth lines up perfectly with the astrophysical models for the 285 00:12:35,360 --> 00:12:38,480 Sun's age. While that gives us incredible confidence in the 286 00:12:38,480 --> 00:12:42,159 five billion year timeline. The two independent fields agree perfectly. 287 00:12:42,480 --> 00:12:46,480 Speaker 1: Okay, So another thought experiment from the source, a terrifying one. 288 00:12:46,679 --> 00:12:50,320 What if the Sun didn't expand but just blanked out? 289 00:12:51,000 --> 00:12:52,360 Right now, what happens to us? 290 00:12:52,720 --> 00:12:54,440 Speaker 2: Well, the first thing is we wouldn't know. 291 00:12:54,480 --> 00:12:56,799 Speaker 1: For a bit, right the eight minute lightspeed delay. 292 00:12:57,039 --> 00:12:59,639 Speaker 3: For eight minutes and twenty seconds, everything would seem normal. 293 00:13:00,200 --> 00:13:03,879 Then suddenly the sky would go completely black. A moment 294 00:13:03,919 --> 00:13:07,039 after that, we'd feel the gravity vanish. Earth would stop 295 00:13:07,159 --> 00:13:09,600 orbiting and just fly off in a straight line into 296 00:13:09,600 --> 00:13:10,720 deep space, and it. 297 00:13:10,720 --> 00:13:13,879 Speaker 1: Would get cold. The source says we'd freeze at minus 298 00:13:13,919 --> 00:13:15,840 four hundred and sixty two degrees fahrenheit. 299 00:13:16,000 --> 00:13:19,360 Speaker 3: That's the background temperature of the universe, about three degrees 300 00:13:19,399 --> 00:13:22,759 above absolute zero. The temperature drop on the surface would 301 00:13:22,759 --> 00:13:26,600 be quick, but not instant. Why not the oceans and 302 00:13:26,679 --> 00:13:29,360 the atmosphere they hold a huge amount of heat. Think 303 00:13:29,360 --> 00:13:32,559 of it like a giant thermal battery. That stored solar 304 00:13:32,679 --> 00:13:35,639 energy would take oh maybe a few weeks, maybe a 305 00:13:35,639 --> 00:13:38,720 few months to radiate away completely. But once it's gone, 306 00:13:38,879 --> 00:13:41,120 we plummet to that deep space temperature. 307 00:13:41,279 --> 00:13:43,759 Speaker 1: So is there any way to survive in the short. 308 00:13:43,600 --> 00:13:45,799 Speaker 3: Term, maybe we'd have to abandon the surface and go 309 00:13:45,840 --> 00:13:49,320 deep underground, relying on the Earth's own internal. 310 00:13:48,840 --> 00:13:50,879 Speaker 1: Heat from the core, right from. 311 00:13:50,840 --> 00:13:55,480 Speaker 3: Geothermal energy, radioactive decay in the core, volcanic vents. That 312 00:13:55,639 --> 00:13:58,320 energy is totally independent of the Sun. You could build 313 00:13:58,360 --> 00:13:59,759 a habitat near one of those, but. 314 00:13:59,679 --> 00:14:01,480 Speaker 1: That's a finite supply too, isn't. 315 00:14:01,320 --> 00:14:02,080 Speaker 2: It It is. 316 00:14:02,440 --> 00:14:05,480 Speaker 3: It would last a very very long time, maybe millions 317 00:14:05,480 --> 00:14:08,600 of years, but eventually the Earth's core would cool two. 318 00:14:09,240 --> 00:14:11,879 The long term goal would have to be finding a 319 00:14:11,919 --> 00:14:13,320 new planet, a new star. 320 00:14:13,840 --> 00:14:14,759 Speaker 2: There's no other. 321 00:14:14,600 --> 00:14:18,440 Speaker 1: Way that shift from these huge cosmic scales back to 322 00:14:18,519 --> 00:14:21,639 our own survival. It leads to one of the most 323 00:14:22,000 --> 00:14:25,600 I think profound ideas in the source material, this idea 324 00:14:25,720 --> 00:14:27,000 of molecular kinship. 325 00:14:27,200 --> 00:14:28,840 Speaker 2: It is an astonishing concept. 326 00:14:28,960 --> 00:14:32,240 Speaker 1: The claim is that every single breath you take contains 327 00:14:32,279 --> 00:14:35,039 molecules that were once inhaled by every other human who 328 00:14:35,120 --> 00:14:35,759 has ever lived. 329 00:14:35,799 --> 00:14:37,919 Speaker 2: It sounds totally impossible until you. 330 00:14:37,919 --> 00:14:39,679 Speaker 1: Do the mas right. It's a numbers game. 331 00:14:39,759 --> 00:14:42,840 Speaker 3: It's all about the sheer number of molecules. Here's the 332 00:14:42,919 --> 00:14:45,919 ratio that breaks your brain. There are more molecules of 333 00:14:45,960 --> 00:14:48,320 air in a single breath you take than there are 334 00:14:48,399 --> 00:14:50,559 breaths of air in the entire atmosphere of the Earth. 335 00:14:50,639 --> 00:14:53,879 Speaker 1: Let we just process that more molecules in one breath. 336 00:14:53,600 --> 00:14:56,240 Speaker 3: Than total breaths in all the air on the whole planet. 337 00:14:56,279 --> 00:14:58,480 The number of molecules is just that much bigger. 338 00:14:58,759 --> 00:15:01,559 Speaker 1: So when I breathe out, those billions and billions of 339 00:15:01,600 --> 00:15:02,399 molecules go out. 340 00:15:02,320 --> 00:15:03,879 Speaker 2: Into the air and they mix. 341 00:15:04,080 --> 00:15:07,320 Speaker 3: The atmosphere is an incredibly efficient mixer. You have wind, 342 00:15:07,480 --> 00:15:12,279 weather patterns, convection. The source says that within about a decade, 343 00:15:12,639 --> 00:15:16,679 those molecules you just exhaled are thoroughly and evenly distributed 344 00:15:16,720 --> 00:15:18,879 across the entire globe, which. 345 00:15:18,679 --> 00:15:21,559 Speaker 1: Means they are guaranteed to be in every breath taken 346 00:15:21,639 --> 00:15:22,960 by every other person on. 347 00:15:22,919 --> 00:15:24,039 Speaker 2: The planet, guaranteed. 348 00:15:24,240 --> 00:15:28,679 Speaker 3: It creates this literal physical connection. You are breathing in 349 00:15:28,759 --> 00:15:31,279 atoms that were once in the lungs of your ancestors, 350 00:15:31,720 --> 00:15:34,120 of Julius Caesar, of every person in history. 351 00:15:34,480 --> 00:15:37,879 Speaker 1: It's a wild thought, a real sense of kinship. 352 00:15:38,039 --> 00:15:39,120 Speaker 2: And it's not just air. 353 00:15:39,440 --> 00:15:42,759 Speaker 3: The source points out the exact same principle applies to water. 354 00:15:43,039 --> 00:15:46,320 Speaker 1: Let me guess the ratio more molecules of water in 355 00:15:46,399 --> 00:15:47,759 a single glass. 356 00:15:47,639 --> 00:15:50,000 Speaker 3: Than there are glasses of water in all the world's 357 00:15:50,039 --> 00:15:50,919 oceans combined. 358 00:15:51,120 --> 00:15:51,840 Speaker 1: That's amazing. 359 00:15:51,879 --> 00:15:53,360 Speaker 3: So when you drink a glass of water and your 360 00:15:53,360 --> 00:15:57,000 body processes it and it eventually returns to the environment 361 00:15:57,039 --> 00:16:00,240 through the water cycle, those molecules scatter, they become part 362 00:16:00,240 --> 00:16:02,279 of the universal reservoir, and they end up in everyone 363 00:16:02,279 --> 00:16:03,559 else's glass of water too. 364 00:16:03,759 --> 00:16:07,279 Speaker 1: So we're all literally sharing the same atoms. When you 365 00:16:07,360 --> 00:16:10,720 realize that this deep interconnectedness, what does that do to you? 366 00:16:11,240 --> 00:16:13,080 Does it make you kinder? Or does it push you 367 00:16:13,120 --> 00:16:15,600 toward nihilism? You know, if we're all just tiny specks 368 00:16:15,639 --> 00:16:18,039 made of the same recycled stuff, does any of it matter? 369 00:16:18,200 --> 00:16:20,639 Speaker 3: That is the philosophical core of it isn't it? And 370 00:16:20,679 --> 00:16:23,919 the source takes a very strong stance against nihilism. 371 00:16:24,279 --> 00:16:25,039 Speaker 2: The argument is. 372 00:16:25,039 --> 00:16:27,759 Speaker 3: That the wisdom you gain from studying the universe contains 373 00:16:27,879 --> 00:16:31,720 no force of nihilism at all. Ohso the proof is 374 00:16:31,759 --> 00:16:35,759 in the behavior. You will not find armies of astrophysicists 375 00:16:35,759 --> 00:16:39,600 marching under a banner of cosmic indifference, slaughtering each other 376 00:16:39,639 --> 00:16:43,159 over borders. The perspective it grants prevents that. 377 00:16:43,320 --> 00:16:46,120 Speaker 1: It's a check on our ego on our petty conflict. 378 00:16:45,759 --> 00:16:46,600 Speaker 2: Now lifts you above it. 379 00:16:46,919 --> 00:16:49,559 Speaker 3: The Source describes it as looking down on human arguments 380 00:16:49,559 --> 00:16:52,559 from a plane of existence above what you're arguing. When 381 00:16:52,600 --> 00:16:55,399 you're thinking about the five billion years until the sun dies, 382 00:16:55,559 --> 00:17:00,000 a fight over a parking spot seems ridiculous, Absolutely ridiculous. 383 00:17:00,080 --> 00:17:00,919 Speaker 2: Frames the whole thing. 384 00:17:01,279 --> 00:17:04,319 Speaker 3: It's not about ignoring problems, but about seeing them in 385 00:17:04,359 --> 00:17:08,359 their true minuscule scale, which gives you the clarity and 386 00:17:08,440 --> 00:17:11,039 humility to solve them without the usual aggression. 387 00:17:11,319 --> 00:17:13,720 Speaker 1: And that idea of humility of seeing ourselves in the 388 00:17:13,720 --> 00:17:17,319 proper scale that leads right into this next really provocative 389 00:17:17,359 --> 00:17:21,160 claim human physiology may be overrated. 390 00:17:20,880 --> 00:17:22,400 Speaker 2: And necessary reality check. 391 00:17:22,440 --> 00:17:26,519 Speaker 3: I think we have this deep seated bias anthroposcentrism that 392 00:17:26,640 --> 00:17:29,440 our physical form is somehow the pinnacle of evolution. 393 00:17:29,680 --> 00:17:31,720 Speaker 1: But the Source argues that's not the case. 394 00:17:31,559 --> 00:17:32,079 Speaker 2: Not at all. 395 00:17:32,119 --> 00:17:34,319 Speaker 3: It argues that the one thing that truly stands out 396 00:17:34,440 --> 00:17:38,039 is our mind, our brain's capacity for abstract thought, for science, 397 00:17:38,160 --> 00:17:42,480 for art. Our physical bodies, they're actually incredibly fragile, so 398 00:17:42,680 --> 00:17:45,359 specialized for this one planet, this one gravity. 399 00:17:45,480 --> 00:17:47,519 Speaker 1: And this feeds right into what the Source calls the 400 00:17:47,599 --> 00:17:51,000 alien paradox. Which is when we imagine aliens, we can't 401 00:17:51,000 --> 00:17:52,039 help but imagine us. 402 00:17:52,160 --> 00:17:52,559 Speaker 2: We do. 403 00:17:52,640 --> 00:17:55,799 Speaker 3: We imagine them with two arms, two legs, ahead eyes, fingers, 404 00:17:55,920 --> 00:17:59,160 a humanoid body plan, and that, the Source argues, is 405 00:17:59,160 --> 00:18:01,480 a profound failure of imagination. 406 00:18:01,160 --> 00:18:03,920 Speaker 1: Because our bodies are just the result of one specific 407 00:18:04,000 --> 00:18:06,920 path evolution took here on Earth exactly. 408 00:18:07,039 --> 00:18:10,079 Speaker 3: Our gravity, our atmosphere, our history of coming out of 409 00:18:10,079 --> 00:18:13,240 the water, all those pressures shaped us. An alien that 410 00:18:13,319 --> 00:18:16,680 evolved on a different world under totally different pressures would 411 00:18:16,680 --> 00:18:18,279 have no reason to look like us. 412 00:18:18,400 --> 00:18:21,240 Speaker 1: The Source gives two great reality checks for this it does. 413 00:18:21,519 --> 00:18:24,400 Speaker 3: The first is just to look around on Earth. A bananatree, 414 00:18:24,480 --> 00:18:28,960 a mushroom, an octopus. They don't have humanoid bodies, yet 415 00:18:28,960 --> 00:18:30,200 we share DNA with them. 416 00:18:30,440 --> 00:18:31,880 Speaker 1: The second reality check. 417 00:18:31,880 --> 00:18:35,160 Speaker 3: An alien from another planet which shares zero DNA with us. 418 00:18:35,319 --> 00:18:38,359 There's no shared ancestry at all. So the idea that 419 00:18:38,400 --> 00:18:42,799 convergent evolution across light years of space would somehow produce 420 00:18:42,880 --> 00:18:47,200 a near identical body plan is well, it's statistically absurd. 421 00:18:47,319 --> 00:18:49,440 Speaker 1: So it truly advanced intelligence might not even have a 422 00:18:49,440 --> 00:18:52,480 body we recognize. It could be a cloud of gas, 423 00:18:52,799 --> 00:18:53,880 a planet sized. 424 00:18:53,640 --> 00:18:56,000 Speaker 2: Fungus, a decentralized consciousness. We just don't know. 425 00:18:56,039 --> 00:18:58,279 Speaker 3: We're so locked into our own physical form that we 426 00:18:58,400 --> 00:19:01,559 keep projecting it onto the star. To truly look for life, 427 00:19:02,039 --> 00:19:03,480 we have to let go of that bias. 428 00:19:03,720 --> 00:19:06,000 Speaker 1: Speaking of things we can barely imagine. What about the 429 00:19:06,039 --> 00:19:09,519 biggest boundary of all, The size of the universe itself 430 00:19:10,200 --> 00:19:10,839 is an infinite? 431 00:19:11,000 --> 00:19:13,960 Speaker 3: The short, honest answer is, we don't know for sure. But, 432 00:19:14,319 --> 00:19:17,480 and this is important, we have no reason to believe. 433 00:19:17,279 --> 00:19:18,079 Speaker 2: It is an infinite. 434 00:19:18,200 --> 00:19:19,160 Speaker 1: Okay, so what do we know. 435 00:19:19,319 --> 00:19:21,759 Speaker 3: We know the size of our observable universe. That's the 436 00:19:21,799 --> 00:19:24,519 part we can see, and it has an edge, a horizon. 437 00:19:24,880 --> 00:19:27,200 Speaker 1: The Source uses a really good analogy for this, the 438 00:19:27,240 --> 00:19:28,160 ship at sea. 439 00:19:28,240 --> 00:19:29,880 Speaker 2: It's the perfect way to think about it. 440 00:19:29,880 --> 00:19:31,640 Speaker 3: If you're on a ship in the middle of the ocean, 441 00:19:32,240 --> 00:19:35,400 you can see the horizon right, a clear edge. But 442 00:19:35,440 --> 00:19:36,599 you know the ocean doesn't end. 443 00:19:36,519 --> 00:19:38,640 Speaker 1: There, right. If you sail towards it, you just see 444 00:19:38,680 --> 00:19:39,319 more ocean. 445 00:19:39,480 --> 00:19:40,839 Speaker 2: A new horizon appears. 446 00:19:42,119 --> 00:19:44,680 Speaker 3: The edge was just the limit of your vision from 447 00:19:44,680 --> 00:19:48,799 your specific location. The universe is like that. Our cosmic 448 00:19:48,839 --> 00:19:52,279 horizon is about fourteen billion light years away in every direction. 449 00:19:52,480 --> 00:19:54,759 That's simply the farthest that light has had time to 450 00:19:54,799 --> 00:19:56,480 travel to reach us since the Big Bang. 451 00:19:56,839 --> 00:19:59,480 Speaker 1: So if we could magically teleport to that edge, we. 452 00:19:59,440 --> 00:20:02,440 Speaker 3: Would just find ourselves in a new patch of universe, 453 00:20:02,720 --> 00:20:06,279 with a whole new observable bubble around us, stretching out 454 00:20:06,279 --> 00:20:09,720 another fourteen billion light years. We can only talk about 455 00:20:09,759 --> 00:20:13,720 a little bubble. What's beyond that is for now conjecture. 456 00:20:13,839 --> 00:20:16,880 Speaker 1: It's mathematically simpler to just assume it goes on forever, 457 00:20:16,920 --> 00:20:17,279 isn't it. 458 00:20:17,359 --> 00:20:20,319 Speaker 3: In many ways, yes, the equations of cosmology work out 459 00:20:20,519 --> 00:20:24,640 very nicely if you assume an infinite, uniform universe. It's 460 00:20:24,720 --> 00:20:27,839 cleaner than trying to invent some kind of arbitrary edge. 461 00:20:28,119 --> 00:20:30,599 So for now we can only speak with certainty about 462 00:20:30,640 --> 00:20:32,720 our own observable horizon, and. 463 00:20:32,640 --> 00:20:35,759 Speaker 1: That limit on what we can observe brings us right 464 00:20:35,799 --> 00:20:40,079 to the public's fascination with well with things that might 465 00:20:40,119 --> 00:20:44,319 be observing us. UFOs UAPs all this military footage that 466 00:20:44,400 --> 00:20:44,920 keeps coming out. 467 00:20:45,079 --> 00:20:49,079 Speaker 3: Yes, and this is where a scientific rigor becomes absolutely essential. 468 00:20:49,079 --> 00:20:51,279 Speaker 2: The source is very firm on this. We have to 469 00:20:51,279 --> 00:20:55,279 be precise with our words. UFO means unidentified flying. 470 00:20:54,960 --> 00:20:57,519 Speaker 1: Object, the keyword being unidentified. 471 00:20:57,599 --> 00:20:58,160 Speaker 2: The keyword. 472 00:20:58,279 --> 00:21:00,599 Speaker 3: The problem is that so many people in imediately make 473 00:21:00,599 --> 00:21:03,799 the leap from UFO to alien spaceship, and those are 474 00:21:03,839 --> 00:21:05,279 not the same thing at all. 475 00:21:05,319 --> 00:21:07,240 Speaker 1: It's a huge logical fallacy, isn't it. 476 00:21:07,240 --> 00:21:10,359 Speaker 2: It's the definition of one. The thinking goes, I don't 477 00:21:10,359 --> 00:21:10,920 know what that. 478 00:21:10,960 --> 00:21:14,200 Speaker 3: Is, therefore it must be an advanced alien from another 479 00:21:14,240 --> 00:21:17,759 star system. The Source just says, look, once you admit 480 00:21:17,799 --> 00:21:19,559 I don't know what it is, that's the end of 481 00:21:19,599 --> 00:21:20,119 the sentence. 482 00:21:20,680 --> 00:21:21,640 Speaker 2: You can't then. 483 00:21:21,559 --> 00:21:25,079 Speaker 3: Jump to an extraordinary conclusion from a position of ignorance. 484 00:21:25,160 --> 00:21:28,559 Speaker 1: It could be anything a weather balloon, a drone, weird. 485 00:21:28,319 --> 00:21:32,799 Speaker 3: Reflection, a secret military project, and atmospheric phenomenon. There's a 486 00:21:32,839 --> 00:21:35,319 long list of possibilities you have to rule out before 487 00:21:35,319 --> 00:21:39,440 you can even begin to consider interstellar visitor. You need 488 00:21:39,839 --> 00:21:43,440 extraordinary evidence for an extraordinary claim. 489 00:21:43,920 --> 00:21:45,759 Speaker 2: A blurry video is not it. 490 00:21:46,599 --> 00:21:49,039 Speaker 1: And then there's the other part of the narrative, the 491 00:21:49,079 --> 00:21:51,960 massive government cover up. The Source has a pretty witty 492 00:21:52,000 --> 00:21:52,519 take on this. 493 00:21:52,720 --> 00:21:54,640 Speaker 3: It's a great observation. It's the irony of what it 494 00:21:54,640 --> 00:21:57,759 calls the competence critique. Explain that the same people who 495 00:21:57,799 --> 00:22:00,720 will tell you often very loudly, but the government is 496 00:22:00,759 --> 00:22:04,680 a bloated, inefficient, incompetent bureaucracy that can't even pave a 497 00:22:04,759 --> 00:22:05,480 road properly. 498 00:22:05,759 --> 00:22:08,720 Speaker 1: Are often the same people who believe that this same 499 00:22:08,880 --> 00:22:15,440 incompetent government has flawlessly executed a perfect, multi decade leak 500 00:22:15,480 --> 00:22:19,519 proof conspiracy to hide the single most important event in 501 00:22:19,599 --> 00:22:20,359 human history. 502 00:22:20,720 --> 00:22:23,160 Speaker 3: The two ideas are mutually exclusive. You can't have it 503 00:22:23,160 --> 00:22:25,839 both ways. If they're capable of that kind of perfect, 504 00:22:25,920 --> 00:22:30,319 silent competence, then they're not the bumbling organization everyone complains about. 505 00:22:30,440 --> 00:22:33,440 Speaker 1: The source also points to a really interesting group of witnesses, 506 00:22:33,759 --> 00:22:35,039 the amateur astronomers. 507 00:22:35,160 --> 00:22:38,359 Speaker 3: Yes and amateur here is a badge of honor. These 508 00:22:38,400 --> 00:22:41,680 aren't just casual stargazers. These people know the night sky 509 00:22:41,759 --> 00:22:44,480 inside and out. They know where Jupiter is supposed to be, 510 00:22:44,880 --> 00:22:47,759 what a satellite flare looks like, how weather affects observation. 511 00:22:48,000 --> 00:22:50,440 Speaker 1: They have the baseline knowledge. They know what's normal. 512 00:22:50,640 --> 00:22:53,000 Speaker 3: Because they know what's normal, they are the least likely 513 00:22:53,039 --> 00:22:56,319 grouped to be fooled by something mundane. And what's fascinating 514 00:22:56,359 --> 00:23:00,000 is that they as a group report fewer unexplainable sightings 515 00:23:00,079 --> 00:23:01,039 than the general public. 516 00:23:01,079 --> 00:23:02,920 Speaker 1: Because they can identify things. 517 00:23:02,799 --> 00:23:05,200 Speaker 3: The moment they see something strange and figure out it's 518 00:23:05,319 --> 00:23:08,799 say a high altitude balloon, it stops being a UFO, 519 00:23:09,119 --> 00:23:12,039 it becomes an IFO and identified flying object. 520 00:23:12,680 --> 00:23:14,640 Speaker 2: Their expertise filters out the noise. 521 00:23:14,799 --> 00:23:18,400 Speaker 1: So, after decades of searching, the scientific community just hasn't 522 00:23:18,440 --> 00:23:22,000 seen the evidence it needs. The Source has this locked 523 00:23:22,039 --> 00:23:23,000 box metaphor. 524 00:23:23,319 --> 00:23:25,359 Speaker 3: Right if if someone tells you I have an alien 525 00:23:25,359 --> 00:23:27,240 in this locked box, but I won't let you open 526 00:23:27,279 --> 00:23:29,240 it or scan it or test it, then from a 527 00:23:29,240 --> 00:23:31,920 scientific perspective, that's exactly. 528 00:23:31,480 --> 00:23:33,319 Speaker 2: The same as not having an alien at all. 529 00:23:33,960 --> 00:23:38,160 Speaker 3: Claims require proof, verifiable, testable, high quality data. 530 00:23:38,039 --> 00:23:41,200 Speaker 1: But other and this is the big turn. After tearing 531 00:23:41,240 --> 00:23:44,799 down the poor evidence, the source makes this incredibly powerful 532 00:23:44,880 --> 00:23:46,720 case for why aliens must exist. 533 00:23:47,240 --> 00:23:50,319 Speaker 3: This is the core conclusion based on pure probability. The 534 00:23:50,359 --> 00:23:53,720 Source is unequivocal. Aliens almost certainly exist out there. The 535 00:23:53,759 --> 00:23:55,079 logic is simple and powerful. 536 00:23:55,160 --> 00:23:56,160 Speaker 1: What's the foundation of it. 537 00:23:56,240 --> 00:23:56,759 Speaker 2: Two things. 538 00:23:56,799 --> 00:23:59,559 Speaker 3: One, the universe is fourteen billion years old. That's an 539 00:23:59,640 --> 00:24:02,160 enormous amount of time for life to get started. Two, 540 00:24:02,359 --> 00:24:05,680 the ingredients for life as we know it, carbon, hydrogen, oxygen, 541 00:24:05,799 --> 00:24:09,559 nitrogen are the most common abundant ingredients in the entire cosmos. 542 00:24:09,799 --> 00:24:11,920 Speaker 1: The raw materials are everywhere, and we have. 543 00:24:11,920 --> 00:24:14,799 Speaker 3: Our own planet as a test case. Life got started 544 00:24:14,799 --> 00:24:17,599 on Earth almost as soon as it possibly could. Once 545 00:24:17,640 --> 00:24:21,200 the planet cooled down, Bang, single celled life appeared within 546 00:24:21,240 --> 00:24:24,720 a couple hundred million years. Nature had no trouble getting 547 00:24:24,720 --> 00:24:25,599 the job done here. 548 00:24:25,759 --> 00:24:29,640 Speaker 1: So if it happened here so easily with common ingredients. 549 00:24:29,359 --> 00:24:32,559 Speaker 3: It's statistically very likely to have happened on a huge 550 00:24:32,640 --> 00:24:37,160 number of other planets. We now know that exoplanets are everywhere, 551 00:24:37,759 --> 00:24:40,880 billions of them in our galaxy alone. To suggest we're 552 00:24:40,920 --> 00:24:44,880 the only ones is, as the source puts it, philosophically irresponsible. 553 00:24:45,000 --> 00:24:47,400 Speaker 1: And we're not just talking about intelligent life, are we. 554 00:24:47,640 --> 00:24:49,119 Speaker 2: No, that's what everyone jumps to. 555 00:24:49,200 --> 00:24:52,480 Speaker 3: But finding any life, even just bacteria on Mars or 556 00:24:52,519 --> 00:24:56,839 algae in an ocean on Europa, would completely revolutionize biology. 557 00:24:56,839 --> 00:24:58,279 Speaker 2: It would be the biggest discovery ever. 558 00:24:58,359 --> 00:25:01,160 Speaker 1: So to understand how little we've actually looked, we need 559 00:25:01,160 --> 00:25:02,559 another Scoale analogy. 560 00:25:02,680 --> 00:25:04,240 Speaker 2: We do our galaxy. 561 00:25:04,279 --> 00:25:07,160 Speaker 3: The Milky Way has a few hundred billion stars. The 562 00:25:07,240 --> 00:25:11,559 observable universe has maybe a trillion galaxies. It's just numbers 563 00:25:11,559 --> 00:25:13,680 on a page until you try to visualize it. In 564 00:25:13,680 --> 00:25:16,400 our search so far, If you imagine our Milky Way 565 00:25:16,440 --> 00:25:19,359 galaxy is the size of a large dining room table, 566 00:25:19,720 --> 00:25:22,480 the entire volume of space we have searched for signs 567 00:25:22,480 --> 00:25:25,359 of life is about the size of a single coin 568 00:25:25,440 --> 00:25:26,400 placed on that table. 569 00:25:26,559 --> 00:25:28,240 Speaker 1: Wow, we barely started. 570 00:25:28,319 --> 00:25:31,039 Speaker 3: We've barely looked out our front door. The Seti Institute 571 00:25:31,039 --> 00:25:33,039 has a great analogy for this. To say there's no 572 00:25:33,240 --> 00:25:35,559 life out there based on our search so far is 573 00:25:35,599 --> 00:25:38,559 like scooping one cup of water from the ocean, finding 574 00:25:38,599 --> 00:25:41,200 no whales in it, and concluding the entire ocean is 575 00:25:41,279 --> 00:25:42,000 empty of whales. 576 00:25:42,079 --> 00:25:45,640 Speaker 1: It's an absurd conclusion. And our search is limited by 577 00:25:45,680 --> 00:25:47,160 time too, not just space. 578 00:25:47,440 --> 00:25:50,519 Speaker 3: That's maybe the biggest hurdle, the synchronicity problem. If an 579 00:25:50,640 --> 00:25:54,480 alien civilization sent a radio message two thousand years ago, 580 00:25:54,720 --> 00:25:55,839 who was here to receive it? 581 00:25:56,240 --> 00:25:59,640 Speaker 2: The Romans? They didn't have radio telescopes. 582 00:25:59,000 --> 00:26:01,200 Speaker 1: And we've only had a technology for about eighty years. 583 00:26:01,400 --> 00:26:05,000 Speaker 3: It's this tiny, tiny window in cosmic history. We have 584 00:26:05,079 --> 00:26:07,680 to be listening at the exact moment a civilization that 585 00:26:07,759 --> 00:26:10,160 is alive at the exact same time as us happens 586 00:26:10,160 --> 00:26:13,240 to be transmitting in our direction. With technology we can detect, 587 00:26:13,559 --> 00:26:15,440 the odds of that overlap are slim. 588 00:26:15,440 --> 00:26:18,880 Speaker 1: But even with all those constraints, the astrophysicist in the 589 00:26:18,920 --> 00:26:21,000 source material ran the numbers. 590 00:26:21,279 --> 00:26:24,880 Speaker 3: They did using a framework like the Drake equation, but 591 00:26:25,079 --> 00:26:28,400 updated with our latest knowledge about exoplanets and the speed 592 00:26:28,400 --> 00:26:31,119 at which life formed here. They came to an estimate. 593 00:26:31,319 --> 00:26:32,680 Speaker 1: And the number is They. 594 00:26:32,559 --> 00:26:37,359 Speaker 3: Calculate there are probably about one hundred living active civilizations 595 00:26:37,400 --> 00:26:39,519 in our Milky Way galaxy right now. 596 00:26:39,759 --> 00:26:43,079 Speaker 1: One hundred. That's incredible, not millions, but not zero. 597 00:26:43,279 --> 00:26:45,720 Speaker 3: It means we're not alone. But the galaxy is not 598 00:26:45,839 --> 00:26:48,799 exactly crowded either. Space is just that big. 599 00:26:49,000 --> 00:26:51,000 Speaker 1: So if they are out there, what happens if we 600 00:26:51,039 --> 00:26:53,759 find them? This is where the source offers a pretty 601 00:26:53,759 --> 00:26:54,880 stark warning. 602 00:26:54,759 --> 00:26:57,400 Speaker 2: A warning that's really about us, not them. 603 00:26:57,920 --> 00:27:01,359 Speaker 3: It points out this irony we are obsessed with meeting 604 00:27:01,400 --> 00:27:05,400 aliens while we actively ignore and destroy the incredible unstudied 605 00:27:05,440 --> 00:27:07,440 species right here on our own. 606 00:27:07,240 --> 00:27:09,480 Speaker 1: Planet, and we tend to project our own nature onto 607 00:27:09,519 --> 00:27:10,359 them constantly. 608 00:27:10,440 --> 00:27:13,640 Speaker 3: Hollywood loves the idea of evil alien invaders, but the 609 00:27:13,680 --> 00:27:16,680 truth is we have zero evidence that aliens would be hostile. 610 00:27:17,000 --> 00:27:19,880 We have, however, thousands of years of undeniable evidence that 611 00:27:19,960 --> 00:27:21,680 humans are hostile to other humans. 612 00:27:21,799 --> 00:27:23,119 Speaker 1: That's the mirror, isn't it. 613 00:27:23,119 --> 00:27:27,279 Speaker 3: It's the mirror. The source points to a brutal historical fact. 614 00:27:28,079 --> 00:27:31,640 Every single time in human history that a technologically advanced 615 00:27:31,640 --> 00:27:35,279 civilization has encountered a less advanced one, it has ended 616 00:27:35,319 --> 00:27:38,640 disastrously for the less advanced group every single time. 617 00:27:38,759 --> 00:27:42,400 Speaker 1: So when we imagine aliens coming here to conquer us 618 00:27:42,559 --> 00:27:43,359 or steal our. 619 00:27:43,240 --> 00:27:46,440 Speaker 3: Resources, you're just imagining what we would do. We're projecting 620 00:27:46,480 --> 00:27:49,000 our own colonial, violent history onto the stars. 621 00:27:49,319 --> 00:27:50,359 Speaker 2: We assume they would. 622 00:27:50,200 --> 00:27:52,200 Speaker 1: Act like us, and if they're advanced enough to cross 623 00:27:52,200 --> 00:27:54,960 the galaxy, they're obviously way way smarter than us. 624 00:27:55,039 --> 00:27:56,839 Speaker 3: I mean, we haven't even been back to the Moon 625 00:27:57,039 --> 00:27:59,880 in over fifty years. A species that can travel, but 626 00:28:00,039 --> 00:28:02,920 queen stars is on a completely different level. The Source 627 00:28:03,039 --> 00:28:06,480 ends with this funny but also kind of sad observation 628 00:28:06,920 --> 00:28:09,440 that if they did show up, our first instinct would 629 00:28:09,440 --> 00:28:12,200 probably be to shoot at them, and they wouldn't be scared, 630 00:28:12,240 --> 00:28:15,079 they wouldn't be defeated. They would probably just laugh at 631 00:28:15,079 --> 00:28:18,240 the primitive little species, turn around and leave, confirming we're 632 00:28:18,279 --> 00:28:21,359 not ready to join the galactic community. So we've gone 633 00:28:21,400 --> 00:28:24,400 from the immense scale of black holes, these singularities we 634 00:28:24,440 --> 00:28:27,599 can only detect by their gravitational shadow, to the ticking 635 00:28:27,640 --> 00:28:31,119 clock of our own son's finite life, and then down 636 00:28:31,160 --> 00:28:35,359 to this incredibly intimate idea of molecular kinship. The fact 637 00:28:35,400 --> 00:28:38,240 that we're all breathing the same historical air, and. 638 00:28:38,160 --> 00:28:42,240 Speaker 1: That cosmic perspective. It really does challenge us, doesn't it. 639 00:28:42,240 --> 00:28:45,440 It suggests our physical form is nothing special, our earthly 640 00:28:45,559 --> 00:28:48,319 fights are petty, and that the universe is almost certainly 641 00:28:48,319 --> 00:28:50,880 full of life, even if we've only just started looking. 642 00:28:51,359 --> 00:28:54,000 Speaker 3: But that brings us back to that final difficult question 643 00:28:54,039 --> 00:28:56,759 about what happens when we do find someone. We know 644 00:28:56,839 --> 00:28:59,240 our own history, We know how the powerful have always 645 00:28:59,279 --> 00:29:02,000 treated the less power, and if we finally need a 646 00:29:02,039 --> 00:29:05,759 civilization that is exponentially more capable than we are, all 647 00:29:05,799 --> 00:29:08,720 of our fears about them are movies, are stories. They 648 00:29:08,759 --> 00:29:11,279 aren't based on any knowledge of who they are. They're 649 00:29:11,319 --> 00:29:14,359 based on a perfect, dark reflection of who we have been. 650 00:29:14,640 --> 00:29:17,720 Speaker 1: So, given that historical pattern of contact here on Earth 651 00:29:18,119 --> 00:29:20,720 and the warning about our own tendencies, what do you 652 00:29:20,759 --> 00:29:24,279 think is the greater risk in finding an advanced alien civilization, 653 00:29:24,720 --> 00:29:29,079 their actual intentions, or our own immediate and probably fearful reaction. 654 00:29:29,240 --> 00:29:30,240 We'd love to know what you think.