1 00:00:07,360 --> 00:00:09,800 Speaker 1: Hey, Daniel, I've kind a dumb question. Oh, those are 2 00:00:09,840 --> 00:00:13,200 Speaker 1: always the hardest questions to answer. Why is it hard 3 00:00:13,200 --> 00:00:16,320 Speaker 1: to come with a dumb answer? He said, You know, 4 00:00:16,520 --> 00:00:20,640 Speaker 1: what people call dumb questions are sometimes really simple, deep questions, 5 00:00:20,680 --> 00:00:22,800 Speaker 1: and those are the hardest but sometimes the most fun 6 00:00:22,920 --> 00:00:26,079 Speaker 1: to tackle. Okay, here's my dumb question, Daniel. Where where 7 00:00:26,120 --> 00:00:29,360 Speaker 1: does space start? You know, like, technically we are in space, 8 00:00:29,400 --> 00:00:31,320 Speaker 1: but we don't think of ourselves in space. We're sort 9 00:00:31,320 --> 00:00:34,440 Speaker 1: of on Earth. There's an official definition a hundred kilometers up. 10 00:00:34,760 --> 00:00:37,640 Speaker 1: That's the official beginning of space and stuff, and that 11 00:00:37,840 --> 00:00:40,520 Speaker 1: sounds totally made up because it's a perfectly round number. 12 00:00:41,479 --> 00:00:43,919 Speaker 1: All right, Well, I guess the question is what is 13 00:00:44,400 --> 00:00:46,680 Speaker 1: a space? Right? It's it's kind of like when you 14 00:00:46,760 --> 00:00:50,080 Speaker 1: no longer have air, or when there's a vacuum. Yeah, exactly. 15 00:00:50,080 --> 00:00:52,800 Speaker 1: It's you know, when you're out there, like deep into space, 16 00:00:52,880 --> 00:00:55,520 Speaker 1: you know, when you're not there here on Earth, and 17 00:00:55,600 --> 00:00:57,840 Speaker 1: the boundary between them is it's a bit funny, you know, 18 00:00:57,840 --> 00:01:01,279 Speaker 1: it's sort of like growing up. You know, officially you're 19 00:01:01,280 --> 00:01:02,880 Speaker 1: grown up on you turn a team, but it's not 20 00:01:02,920 --> 00:01:06,959 Speaker 1: like a moment when you suddenly get wisdom and context 21 00:01:07,040 --> 00:01:10,080 Speaker 1: and vision and understanding and perspective, and you can make 22 00:01:10,120 --> 00:01:12,880 Speaker 1: grown up decisions. You know. It's something that very slowly happens. 23 00:01:13,280 --> 00:01:15,600 Speaker 1: Well Offecially, the government does give you a certificate in 24 00:01:15,640 --> 00:01:20,080 Speaker 1: your a team. That's right, Please register for the army. Congratulations, 25 00:01:20,080 --> 00:01:23,399 Speaker 1: I'm being an adult. Yeah, you saying technically, I I'm 26 00:01:23,480 --> 00:01:25,800 Speaker 1: I haven't grown up like technically you may. You may 27 00:01:25,840 --> 00:01:28,280 Speaker 1: never grow up. That's right. You and Peter Pan are 28 00:01:28,280 --> 00:01:31,360 Speaker 1: officially not grown up. There you go, Peter Pan, the 29 00:01:31,400 --> 00:01:52,480 Speaker 1: first thats wrong? That's probably truck too. H I am 30 00:01:52,600 --> 00:01:55,800 Speaker 1: or Hey, I'm a cartoonist and the creator of PhD Comics. Hi. 31 00:01:55,920 --> 00:01:58,280 Speaker 1: I'm Daniel Whitson. I'm a part of the physicist I 32 00:01:58,320 --> 00:02:01,400 Speaker 1: work at certain smashing stuff together to reveal the secrets 33 00:02:01,400 --> 00:02:04,440 Speaker 1: of the universe. And I am not a cartoonist. That's right. Also, 34 00:02:04,440 --> 00:02:06,280 Speaker 1: I forgot to mention, I'm also not if this isis 35 00:02:06,600 --> 00:02:09,519 Speaker 1: but in any case, welcome to our podcast Daniel and 36 00:02:09,600 --> 00:02:12,840 Speaker 1: Jorge Explained the Universe, a production of I Heart Radio 37 00:02:12,960 --> 00:02:15,799 Speaker 1: where we explain all the crazy and amazing things that 38 00:02:15,840 --> 00:02:18,200 Speaker 1: are out there in the universe and we have long 39 00:02:18,240 --> 00:02:20,920 Speaker 1: conversations about it. That's right. We're gonna take a mind 40 00:02:21,040 --> 00:02:23,280 Speaker 1: blowing tour of all the crazy stuff out there in 41 00:02:23,280 --> 00:02:25,280 Speaker 1: the universe. And the most important thing is that we're 42 00:02:25,280 --> 00:02:27,079 Speaker 1: going to do our best to explain in a way 43 00:02:27,120 --> 00:02:30,280 Speaker 1: that actually makes sense to you and hopefully entertains you 44 00:02:30,320 --> 00:02:32,720 Speaker 1: along the way. I mean, where else can you sit 45 00:02:32,800 --> 00:02:36,400 Speaker 1: for an hour and hear about nothing? Literally nothing? That's right. 46 00:02:36,680 --> 00:02:39,320 Speaker 1: We are going to get spacey today, folks. That's right. 47 00:02:39,320 --> 00:02:41,560 Speaker 1: Today on the program, we're gonna be asking the question 48 00:02:46,600 --> 00:02:51,480 Speaker 1: can space be empty? Truly empty? Like nothing? That's right? 49 00:02:51,840 --> 00:02:54,280 Speaker 1: What's actually out there in space? If you went out 50 00:02:54,320 --> 00:02:57,240 Speaker 1: into space and you like grabbed a big box and 51 00:02:57,240 --> 00:03:00,600 Speaker 1: and closed up some space, what would you capture? Is 52 00:03:00,639 --> 00:03:03,840 Speaker 1: space pretty empty? Is it mostly full of stuff that's invisible? 53 00:03:03,960 --> 00:03:06,080 Speaker 1: What's going on out there in space? And you can 54 00:03:06,080 --> 00:03:08,360 Speaker 1: think of this question for those of you keeping track 55 00:03:08,400 --> 00:03:12,000 Speaker 1: at home as part of our Extreme Universe series, This 56 00:03:12,040 --> 00:03:15,080 Speaker 1: one sort of like what is the emptiest place in 57 00:03:15,120 --> 00:03:18,760 Speaker 1: the universe? Where in the universe is space? The space 58 00:03:19,040 --> 00:03:22,160 Speaker 1: is yeah, I think most importantly, can it be empty? 59 00:03:22,200 --> 00:03:26,359 Speaker 1: Like is it possible to have nothingness in space? That's right? Yeah, 60 00:03:26,360 --> 00:03:27,960 Speaker 1: And that's a fun question too, like do you mean 61 00:03:28,040 --> 00:03:32,360 Speaker 1: experimentally like could we build something which makes a cubic 62 00:03:32,440 --> 00:03:35,960 Speaker 1: meter of truly empty space? Or theoretically, like is it 63 00:03:36,280 --> 00:03:38,280 Speaker 1: is it against the laws of physics for space to 64 00:03:38,320 --> 00:03:41,160 Speaker 1: be empty? Yeah? Or I mean just are there's are 65 00:03:41,200 --> 00:03:43,600 Speaker 1: there spots out there in the huge universe that we 66 00:03:43,680 --> 00:03:46,280 Speaker 1: live in that are really truly empty? Do you know 67 00:03:46,280 --> 00:03:48,400 Speaker 1: what I mean? Like we know that you know that 68 00:03:48,600 --> 00:03:50,360 Speaker 1: we know the stuff right here on Earth, on on 69 00:03:50,440 --> 00:03:53,119 Speaker 1: this planet, but are there parts of the universe where 70 00:03:53,160 --> 00:03:55,960 Speaker 1: there's truly nothing in there? That's right? Because the universe 71 00:03:56,120 --> 00:03:59,280 Speaker 1: is huge, it certainly a lot of space out there, right, 72 00:03:59,360 --> 00:04:01,440 Speaker 1: and not that much stuff. You know, you just look 73 00:04:01,480 --> 00:04:04,200 Speaker 1: up at the night sky and it's mostly space, right, 74 00:04:04,200 --> 00:04:06,160 Speaker 1: There's not that many stars, even if you have a 75 00:04:06,240 --> 00:04:09,400 Speaker 1: really amazing telescope because he really really far away, there's 76 00:04:09,400 --> 00:04:12,400 Speaker 1: a lot more space than stars. And so that makes 77 00:04:12,440 --> 00:04:14,720 Speaker 1: me wonder, and I think other people wonder, like what's 78 00:04:14,760 --> 00:04:17,760 Speaker 1: in that space? How empty is it? How much stuff 79 00:04:18,120 --> 00:04:22,520 Speaker 1: is there in space? How spacey is space? How spacious? 80 00:04:22,560 --> 00:04:24,679 Speaker 1: I think maybe the question is how spacious is space? 81 00:04:25,360 --> 00:04:28,200 Speaker 1: How spacious in space? Exactly? Is there room for me 82 00:04:28,279 --> 00:04:30,160 Speaker 1: to move out there and like really spread out with 83 00:04:30,200 --> 00:04:32,520 Speaker 1: my stuff? You got a lot of stuff in storage. 84 00:04:32,520 --> 00:04:35,359 Speaker 1: You're gonna take out an unpack, right, Yeah. And we 85 00:04:35,440 --> 00:04:38,479 Speaker 1: have had podcasts about how big the universe is, right, 86 00:04:38,640 --> 00:04:41,440 Speaker 1: and what's the biggest thing in the universe, But this 87 00:04:41,480 --> 00:04:44,839 Speaker 1: is the first time we're asking can't space actually be empty? Yeah? Exactly? 88 00:04:44,880 --> 00:04:48,000 Speaker 1: How empty is it? So as usual, before we dig 89 00:04:48,000 --> 00:04:50,920 Speaker 1: into the topic, I thought I would crowdsource of information, 90 00:04:50,960 --> 00:04:52,960 Speaker 1: and I walked around the UC Irvine campus and I 91 00:04:53,000 --> 00:04:55,679 Speaker 1: asked people, what do you think would be in a 92 00:04:55,839 --> 00:04:58,479 Speaker 1: random cubic meter of space? How empty is it? Is 93 00:04:58,480 --> 00:05:01,440 Speaker 1: there stuff out there? Or is it mostly empty? Yeah? 94 00:05:01,640 --> 00:05:04,000 Speaker 1: So thank for a moment before you hear the answers, 95 00:05:04,040 --> 00:05:07,000 Speaker 1: and ask yourself if you encountered a random physicist on 96 00:05:07,040 --> 00:05:09,279 Speaker 1: the street and they asked you, what do you think 97 00:05:09,360 --> 00:05:12,000 Speaker 1: is in a one cubic meter of space? What would 98 00:05:12,000 --> 00:05:15,000 Speaker 1: you answer? Here's what people had to say, what's in 99 00:05:15,480 --> 00:05:21,360 Speaker 1: a random cubic meter of empty space? Do you think of? Adams? Adams? 100 00:05:21,760 --> 00:05:29,599 Speaker 1: That's all I can think of. Jeez, I'm not too sure. Um, 101 00:05:29,640 --> 00:05:31,719 Speaker 1: I don't know. I know that the particles is what 102 00:05:31,760 --> 00:05:39,960 Speaker 1: I'd assume, cubic million, moleculous, preaky million. I don't know. 103 00:05:42,720 --> 00:05:44,840 Speaker 1: Guessing it depends where you're on. I mean, if you're 104 00:05:44,839 --> 00:05:47,320 Speaker 1: out in space, it'll just be filled with space. I 105 00:05:47,320 --> 00:05:49,680 Speaker 1: mean if it's space is empty, then there's nothing. I'm 106 00:05:49,680 --> 00:05:54,680 Speaker 1: assuming of the matter. We know, probably nothing, but there 107 00:05:54,720 --> 00:05:58,320 Speaker 1: could be dark energy and that cubic meter or dark 108 00:05:59,000 --> 00:06:04,800 Speaker 1: dark matter. Cool third reaffraightation. Awesome, thanks very much, dark matters, 109 00:06:04,839 --> 00:06:08,359 Speaker 1: dark quarters, dark matter, and yeah, I mean I'll watchally 110 00:06:08,400 --> 00:06:13,640 Speaker 1: all dark matter. What about like far between galaxies? Um, 111 00:06:13,839 --> 00:06:15,480 Speaker 1: is the dark matter everywhere? Or is it just near 112 00:06:15,560 --> 00:06:19,400 Speaker 1: the galaxies? No, it's I think it's like every open space. 113 00:06:19,440 --> 00:06:23,400 Speaker 1: You're like like in between like planets and stars and cool, 114 00:06:23,920 --> 00:06:26,120 Speaker 1: all right, I would say that there's stuff in there. 115 00:06:26,200 --> 00:06:28,960 Speaker 1: I wouldn't say it was like completely empty space. It's 116 00:06:28,960 --> 00:06:32,239 Speaker 1: probably a bunch of its particles or components of something. 117 00:06:32,279 --> 00:06:36,960 Speaker 1: I would say, okay, dust, there are different types of particles. 118 00:06:37,240 --> 00:06:40,640 Speaker 1: Is it totally empty? Vacuum energy? I guess all right, cool, 119 00:06:41,720 --> 00:06:45,200 Speaker 1: you'd probably get some particles of some swords like how 120 00:06:45,200 --> 00:06:50,520 Speaker 1: many holding up to like eight grade science? Al Right? 121 00:06:50,640 --> 00:06:53,919 Speaker 1: I like, I like, um, most people just said stuff 122 00:06:54,520 --> 00:06:58,160 Speaker 1: like I feel like, did you just say maybe? I mean, 123 00:06:58,240 --> 00:06:59,960 Speaker 1: you couldn't just say the Big Bang that would have 124 00:07:00,000 --> 00:07:04,560 Speaker 1: in it physics remnants of the Big Bang. I mean 125 00:07:04,560 --> 00:07:07,360 Speaker 1: that's always correct, but stuff is also pretty versatile as 126 00:07:07,520 --> 00:07:09,560 Speaker 1: as a physics answer. Well, that's sort of the question 127 00:07:09,760 --> 00:07:12,640 Speaker 1: is space have any stuff in it? And so if 128 00:07:12,640 --> 00:07:14,960 Speaker 1: you want to make it binary, like you know it's 129 00:07:15,000 --> 00:07:16,880 Speaker 1: empty or there's stuff and it, then these people were 130 00:07:16,960 --> 00:07:19,160 Speaker 1: voting for stuff. I think a lot of people have 131 00:07:19,280 --> 00:07:21,800 Speaker 1: the sense that space is not truly empty, that there's 132 00:07:21,840 --> 00:07:24,360 Speaker 1: always something in there, even if you can't see it. Oh, 133 00:07:24,560 --> 00:07:28,640 Speaker 1: I see you're saying that most people didn't say nothing 134 00:07:29,840 --> 00:07:32,559 Speaker 1: or vacuum. Do you know what I mean? Like, most 135 00:07:32,600 --> 00:07:35,840 Speaker 1: people assumed that they had stuff in it. Yeah, exactly. 136 00:07:35,920 --> 00:07:37,560 Speaker 1: That was the sense that I got from most people 137 00:07:37,560 --> 00:07:39,640 Speaker 1: that they weren't quite sure what was in there. They 138 00:07:39,640 --> 00:07:42,400 Speaker 1: thought it was mostly empty, but not truly empty. There 139 00:07:42,480 --> 00:07:45,760 Speaker 1: was still some residual stuff in there. So if you're 140 00:07:45,840 --> 00:07:49,560 Speaker 1: giving a test annual in a student, you as like, um, hey, 141 00:07:49,600 --> 00:07:53,640 Speaker 1: what is quantum physics? And the student writes stuff, what 142 00:07:53,680 --> 00:07:55,920 Speaker 1: would you would you taken a clean market wrong? Oh 143 00:07:56,000 --> 00:07:58,880 Speaker 1: for sure, yeah, but I always give credit. Um, I 144 00:07:58,880 --> 00:08:00,600 Speaker 1: always have a lot of partial it and you always 145 00:08:00,600 --> 00:08:03,800 Speaker 1: get some points for writting down anything like even stray 146 00:08:03,880 --> 00:08:06,600 Speaker 1: pencil marks. I will get partial credit for sometimes really, 147 00:08:07,240 --> 00:08:10,120 Speaker 1: because when it's when they leave the space empty that 148 00:08:10,200 --> 00:08:14,400 Speaker 1: you really bothers you exactly pure empty space that bothers me. 149 00:08:14,680 --> 00:08:17,239 Speaker 1: For that, you get a zero right reflecting the amount 150 00:08:17,280 --> 00:08:19,240 Speaker 1: of effort you put into the problem. But you write 151 00:08:19,240 --> 00:08:22,840 Speaker 1: down something anything, um, I'll give you some points. Maybe 152 00:08:22,840 --> 00:08:24,160 Speaker 1: you didn't know this. At the end of all of 153 00:08:24,200 --> 00:08:28,680 Speaker 1: my mid terms, I also do a physics cartoon contest. Really, yeah, 154 00:08:28,960 --> 00:08:31,480 Speaker 1: what do you mean? I pick a random cartoon from 155 00:08:31,480 --> 00:08:34,480 Speaker 1: the New Yorker, usually that looks a little physically like 156 00:08:34,520 --> 00:08:37,160 Speaker 1: there's a wheel or something physically in it, and I 157 00:08:37,200 --> 00:08:40,959 Speaker 1: asked them to write a physics related caption for that 158 00:08:41,000 --> 00:08:44,800 Speaker 1: cartoon related to what they learned on the exam. Well, 159 00:08:44,800 --> 00:08:49,319 Speaker 1: hopefully they didn't learn it on the exam hopefully before 160 00:08:48,760 --> 00:08:52,760 Speaker 1: for yeah. And then I have the ta tas always 161 00:08:52,760 --> 00:08:54,800 Speaker 1: created and I tell them if they write anything, give 162 00:08:54,880 --> 00:08:57,160 Speaker 1: them a point. If they write something that actually makes 163 00:08:57,200 --> 00:09:01,000 Speaker 1: you laugh, give them two points. And you know, sometimes 164 00:09:01,000 --> 00:09:03,520 Speaker 1: these kids are pretty funny. I can imagine being stress 165 00:09:03,600 --> 00:09:05,959 Speaker 1: stressed out student thinking, oh my gosh, should I devote 166 00:09:06,000 --> 00:09:07,480 Speaker 1: my last two minutes of trying to come up with 167 00:09:07,520 --> 00:09:10,400 Speaker 1: a clever caption, or should I try to solve this 168 00:09:10,480 --> 00:09:14,400 Speaker 1: quantum physics problem. Well, I hope it will get more pointive. 169 00:09:14,440 --> 00:09:16,040 Speaker 1: I hope you give them a little bit of stress relief. 170 00:09:16,040 --> 00:09:19,559 Speaker 1: But it's actually some interesting stuff in the physics education 171 00:09:19,679 --> 00:09:23,320 Speaker 1: literature that shows that making people think about the the 172 00:09:23,800 --> 00:09:26,240 Speaker 1: about physics in the context of their real lives or 173 00:09:26,280 --> 00:09:29,920 Speaker 1: in real life contexts helps them understand these concepts. So 174 00:09:29,960 --> 00:09:31,880 Speaker 1: it's not just a joke on my part. It's like, 175 00:09:31,920 --> 00:09:34,160 Speaker 1: I really think that it helps them understand. They have 176 00:09:34,200 --> 00:09:37,079 Speaker 1: to think about, how is this relevant to some situation? 177 00:09:37,640 --> 00:09:40,800 Speaker 1: Oh interesting, haven't kind of take a step back and 178 00:09:41,720 --> 00:09:44,240 Speaker 1: try to find a think about the context of the 179 00:09:44,240 --> 00:09:47,480 Speaker 1: stuff they learned. Yeah, exactly exactly, because we don't learn 180 00:09:47,559 --> 00:09:49,679 Speaker 1: everything in the vacuum, right, it's not just out there 181 00:09:49,720 --> 00:09:52,480 Speaker 1: floating in space. Right. Well, now, now I'm a little 182 00:09:52,520 --> 00:09:54,439 Speaker 1: nervous for the universe. I feel like if the universe 183 00:09:54,800 --> 00:09:57,280 Speaker 1: is truly can be truly empty, you might give it 184 00:09:57,520 --> 00:10:01,240 Speaker 1: zero points, no partial. Well, you know the universe is 185 00:10:01,280 --> 00:10:05,000 Speaker 1: making it ever um talking about being truly empty. When 186 00:10:05,000 --> 00:10:07,400 Speaker 1: I was doing some reading for this episode, I was 187 00:10:07,440 --> 00:10:10,560 Speaker 1: shocked to discover some things about what we consider empty 188 00:10:10,600 --> 00:10:13,400 Speaker 1: space here on Earth. You know, here on Earth, we 189 00:10:13,520 --> 00:10:16,559 Speaker 1: can do things that create vacuum in the lab, right, 190 00:10:17,040 --> 00:10:19,200 Speaker 1: people do this to to do all sorts of experiments, 191 00:10:19,200 --> 00:10:21,840 Speaker 1: and we have pretty good vacuum for example, the large 192 00:10:21,880 --> 00:10:24,720 Speaker 1: age on collider where we smash protons together. We suck 193 00:10:24,760 --> 00:10:26,360 Speaker 1: all the other stuff out because we don't want it 194 00:10:26,400 --> 00:10:28,880 Speaker 1: to interfere with the collisions. But it turns out that 195 00:10:28,880 --> 00:10:32,760 Speaker 1: that vacuum is not really empty like at all. If 196 00:10:32,800 --> 00:10:35,160 Speaker 1: you look at the density of air that we're breathing, 197 00:10:35,200 --> 00:10:38,160 Speaker 1: like the air that I'm breathing right now, there's about 198 00:10:38,360 --> 00:10:42,120 Speaker 1: ten to the twenty five molecules per cubic meter. So 199 00:10:42,160 --> 00:10:45,840 Speaker 1: that's a huge number, right, like ten with twenty five zeros. 200 00:10:45,880 --> 00:10:48,280 Speaker 1: I don't even know what the scientific prefixes for like. 201 00:10:48,320 --> 00:10:51,440 Speaker 1: And it's all like air molecules and gas molecules. And 202 00:10:53,360 --> 00:10:56,160 Speaker 1: and when they when they make vacuum, they pump the 203 00:10:56,160 --> 00:10:58,120 Speaker 1: air out, right, they suck it all out. Sometimes they 204 00:10:58,160 --> 00:11:00,120 Speaker 1: even bake it to try to get as much the 205 00:11:00,120 --> 00:11:02,440 Speaker 1: air out of it as possible. And you'd imagine they 206 00:11:02,480 --> 00:11:04,800 Speaker 1: maybe they get it down to really pretty good vacuum. 207 00:11:05,040 --> 00:11:07,559 Speaker 1: But what they call like ultra high vacuum in the 208 00:11:07,640 --> 00:11:11,000 Speaker 1: lab still has like ten to the twelve or ten 209 00:11:11,040 --> 00:11:14,839 Speaker 1: to the fifteen particles per cubic meter, which is still 210 00:11:14,840 --> 00:11:17,720 Speaker 1: a huge number, right, I mean it's a much smaller number. 211 00:11:17,960 --> 00:11:22,000 Speaker 1: You're down like ten or fifteen orders of magnitude, but 212 00:11:22,320 --> 00:11:25,520 Speaker 1: super high vacuum here on Earth is filled with particles. 213 00:11:26,400 --> 00:11:28,160 Speaker 1: What do you think is a limitation? Why can't they 214 00:11:28,200 --> 00:11:31,040 Speaker 1: suck out those last few particles? I mean last few 215 00:11:31,040 --> 00:11:32,959 Speaker 1: by me, I mean the last ten to the fifteen 216 00:11:33,160 --> 00:11:36,960 Speaker 1: part exactly. It's difficult. You know, you've gotta have really 217 00:11:36,960 --> 00:11:39,640 Speaker 1: powerful pumps, and you've gotta have no leaks. You know, 218 00:11:39,720 --> 00:11:43,120 Speaker 1: it's really pretty tricky. It's hard to get nothingness, like 219 00:11:43,160 --> 00:11:45,800 Speaker 1: to pull everything out of a space, yeah, because the 220 00:11:45,840 --> 00:11:48,800 Speaker 1: pressure on it is tremendous. Right, If there's nothing in it, 221 00:11:49,000 --> 00:11:51,040 Speaker 1: then things are pressing on it from all sides, and 222 00:11:51,080 --> 00:11:53,640 Speaker 1: then there's nothing in it to push back, right, So 223 00:11:53,679 --> 00:11:55,600 Speaker 1: things are trying to squeeze in everywhere. So you have 224 00:11:55,679 --> 00:11:58,800 Speaker 1: like the tiniest little gap, like an atom sized gap 225 00:11:58,880 --> 00:12:01,240 Speaker 1: in your in your well did seem or something, and 226 00:12:01,280 --> 00:12:03,640 Speaker 1: particles are going to find their way through. It's a 227 00:12:03,720 --> 00:12:07,119 Speaker 1: very powerful pressure from the outside, and you know, vacuums 228 00:12:07,160 --> 00:12:10,040 Speaker 1: don't suck, right, It's not like the vacuum inside this 229 00:12:10,080 --> 00:12:13,040 Speaker 1: machine is like actively sucking stuff in. It's all the 230 00:12:13,080 --> 00:12:16,720 Speaker 1: air outside that's pressing down, that's pushing in. Wait, what 231 00:12:16,760 --> 00:12:20,080 Speaker 1: do you mean it's not the vacuum. Well, you can 232 00:12:20,080 --> 00:12:22,040 Speaker 1: think about it in two ways, but I never like 233 00:12:22,080 --> 00:12:24,760 Speaker 1: thinking about the vacuum is like actively sucking stuff in. 234 00:12:24,840 --> 00:12:27,920 Speaker 1: It's not like there's something inside a vacuum chamber that's 235 00:12:27,960 --> 00:12:33,080 Speaker 1: going right. The reason things like things get sucked into 236 00:12:33,080 --> 00:12:35,800 Speaker 1: a vacuum, it's not like a black hole black holes 237 00:12:35,840 --> 00:12:39,720 Speaker 1: actively pulling stuff in. The reason things um rush into 238 00:12:39,760 --> 00:12:45,040 Speaker 1: a vacuum is because the air is being pressed into it. Right. Well, 239 00:12:45,080 --> 00:12:48,160 Speaker 1: you know, my grandma used to say, nature abhorts a vacuum. 240 00:12:48,440 --> 00:12:51,120 Speaker 1: Did your grandma invent that? Right? I think she invented that. 241 00:12:51,160 --> 00:12:53,280 Speaker 1: I'm not quite sure, but she used to say it. All. 242 00:12:53,760 --> 00:12:57,800 Speaker 1: My grandma used to say, I think therefore, I am wow, 243 00:12:58,360 --> 00:13:04,200 Speaker 1: that is still original. Over they are Our grammars were contemporaries, 244 00:13:04,440 --> 00:13:08,640 Speaker 1: geniuses of modern philosophy. She said, she ab pours vacuuming. 245 00:13:08,640 --> 00:13:15,600 Speaker 1: I'm not quite sure which one, probably probably the ladder. Okay, sorry, yeah, 246 00:13:15,679 --> 00:13:22,959 Speaker 1: exactly say you're in a spaceship, right and there's a leak, right, 247 00:13:23,520 --> 00:13:26,559 Speaker 1: then is the vacuum sucking all the air out of 248 00:13:26,600 --> 00:13:28,480 Speaker 1: the ship. No, it's the air and the ship is 249 00:13:28,520 --> 00:13:30,679 Speaker 1: like a balloon. It's under high pressure and you get 250 00:13:30,679 --> 00:13:33,480 Speaker 1: a leak and the air is pushing itself out. Right. 251 00:13:33,800 --> 00:13:36,400 Speaker 1: So the reason when you when they open the airlock 252 00:13:36,480 --> 00:13:38,400 Speaker 1: on a spaceship on a movie and you get that 253 00:13:38,440 --> 00:13:41,760 Speaker 1: tremendous wind, it's not the space sucking the air out 254 00:13:41,760 --> 00:13:44,600 Speaker 1: of the spaceship. It's the air pushing itself out because 255 00:13:44,600 --> 00:13:48,320 Speaker 1: it's under pressure. Okay, So we're talking about space and 256 00:13:48,320 --> 00:13:51,959 Speaker 1: whether space can be truly empty, right, and so the 257 00:13:52,040 --> 00:13:55,079 Speaker 1: question it is space like the perfect vacuum. Is there 258 00:13:55,120 --> 00:13:57,360 Speaker 1: really nothing out there? And the point I wanted to 259 00:13:57,360 --> 00:13:59,720 Speaker 1: make was that even super good vacuums here on Earth 260 00:13:59,800 --> 00:14:02,600 Speaker 1: are pretty terrible when it comes to when it comes 261 00:14:02,600 --> 00:14:04,640 Speaker 1: to relationships to space. So I just wanted to set 262 00:14:04,679 --> 00:14:07,200 Speaker 1: that stage right that we're gonna be talking about a 263 00:14:07,200 --> 00:14:10,240 Speaker 1: certain number of molecules per per cubic meter and the 264 00:14:10,360 --> 00:14:13,040 Speaker 1: air you breathe. This tend to the twenty five molecules 265 00:14:13,040 --> 00:14:15,800 Speaker 1: per cubic meter and the air and a super awesome, 266 00:14:15,880 --> 00:14:18,840 Speaker 1: fancy vacuum is like ten to the twelve particles per 267 00:14:18,880 --> 00:14:22,880 Speaker 1: cubic meter. Okay, so that that that's like the goal 268 00:14:22,960 --> 00:14:25,760 Speaker 1: you're saying, that's the gold standards for vacuum nows here 269 00:14:25,760 --> 00:14:29,080 Speaker 1: on Earth. That's right, Yeah, in terms of human engineering exactly. Yeah. 270 00:14:29,640 --> 00:14:32,840 Speaker 1: And um, so so let's take a tour, right, Let's 271 00:14:32,840 --> 00:14:36,040 Speaker 1: go up from the planet and think about and explore 272 00:14:36,080 --> 00:14:38,600 Speaker 1: space and and talk about how much stuff there is 273 00:14:38,600 --> 00:14:41,200 Speaker 1: in space as we leave the Earth, because the fascinating 274 00:14:41,240 --> 00:14:43,800 Speaker 1: thing to me is the amount of stuff in space. 275 00:14:43,840 --> 00:14:47,760 Speaker 1: The emptiness of space changes where you're depending on where 276 00:14:47,800 --> 00:14:51,440 Speaker 1: you are in space. So the answer to the question 277 00:14:51,520 --> 00:14:55,920 Speaker 1: is can space be empty you're saying, changes depending on 278 00:14:55,920 --> 00:14:59,440 Speaker 1: on where you are. Yeah, there's different levels of spaces. Yeah, 279 00:14:59,600 --> 00:15:03,680 Speaker 1: different levels of spaciness exactly. So for example, um, let's 280 00:15:03,680 --> 00:15:05,520 Speaker 1: dig into it. Like, if you take off from the 281 00:15:05,560 --> 00:15:08,240 Speaker 1: Earth and you leave the Earth's atmosphere and you're out 282 00:15:08,280 --> 00:15:11,840 Speaker 1: in space, then you're you're in this extended region we 283 00:15:11,920 --> 00:15:15,400 Speaker 1: call the heliosphere, which is where the Sun dominates and 284 00:15:15,440 --> 00:15:18,000 Speaker 1: the Sun is pumping out particles all the time. We 285 00:15:18,040 --> 00:15:20,520 Speaker 1: call it the solar wind. So yeah, you're far away 286 00:15:20,520 --> 00:15:22,760 Speaker 1: from the Earth's atmosphere, but you're in this region of 287 00:15:22,800 --> 00:15:26,680 Speaker 1: space that's filled with particles streaming from the Sun. And 288 00:15:27,080 --> 00:15:31,400 Speaker 1: that's basically the entire Solar system, right, I mean, basically 289 00:15:31,400 --> 00:15:35,320 Speaker 1: the entire Solar System is kind of within the heliosphere. Yeah, exactly, 290 00:15:35,480 --> 00:15:37,360 Speaker 1: the entire Solar system. And if you look, if you 291 00:15:37,400 --> 00:15:40,920 Speaker 1: Google image search heliosphere, you'll see that the heliosphere is 292 00:15:41,080 --> 00:15:44,400 Speaker 1: much bigger than like even the orbit of Pluto, because 293 00:15:44,400 --> 00:15:47,280 Speaker 1: the soul of the Sun dominates the local environment. At 294 00:15:47,280 --> 00:15:50,640 Speaker 1: some point, Peter's out and like the magnetic fields inside 295 00:15:50,640 --> 00:15:53,800 Speaker 1: the galaxy start to take over. But in the environment 296 00:15:53,800 --> 00:15:56,760 Speaker 1: around the Sun, you know, the the space in our 297 00:15:56,800 --> 00:15:59,560 Speaker 1: Solar system is dominated by the solar wind, and the 298 00:15:59,560 --> 00:16:02,240 Speaker 1: solar wind has all these particles that come from the 299 00:16:02,280 --> 00:16:04,640 Speaker 1: outer level of plasma of the Sun, which is obviously 300 00:16:04,840 --> 00:16:08,400 Speaker 1: glowing hot and shooting out light, but also shooting out 301 00:16:08,400 --> 00:16:11,720 Speaker 1: electrons and protons and other kind of radiation. So you're 302 00:16:11,760 --> 00:16:16,320 Speaker 1: saying the space in between planets, like between here and Mars, 303 00:16:16,400 --> 00:16:19,080 Speaker 1: here and Jupiter here in the Sun, it's not empty 304 00:16:19,120 --> 00:16:22,680 Speaker 1: at all. It's like it's full of sunweather exactly. It's 305 00:16:22,720 --> 00:16:26,160 Speaker 1: full of solar weather and it's about five to ten 306 00:16:26,360 --> 00:16:29,640 Speaker 1: million protons per cubic meter, which is still you know, 307 00:16:29,920 --> 00:16:33,160 Speaker 1: a hundred or a thousand times better than the vacuum 308 00:16:33,240 --> 00:16:35,600 Speaker 1: chambers we have on Earth. But it's not in zero. 309 00:16:36,120 --> 00:16:38,880 Speaker 1: So you said protons. Are you saying protons mostly because 310 00:16:38,880 --> 00:16:41,880 Speaker 1: that's that's those are matter particles? Yeah, exactly. Well, the 311 00:16:41,880 --> 00:16:45,320 Speaker 1: solar wind is mostly electrons and protons and a few 312 00:16:45,320 --> 00:16:48,240 Speaker 1: other kinds of particles, but mostly it's it's it's those 313 00:16:48,240 --> 00:16:50,280 Speaker 1: protons and electrons, and so you count them in turn. 314 00:16:50,320 --> 00:16:52,440 Speaker 1: And the protons are much heavier than the electrons, so 315 00:16:52,480 --> 00:16:55,560 Speaker 1: they dominate the calculation. Oh, I see they count of stuff, 316 00:16:56,000 --> 00:16:58,400 Speaker 1: but like photons, and do they count it stuff photons? 317 00:16:58,480 --> 00:17:02,840 Speaker 1: Do photons counts stuff? Hmm, that's a good question. Um. 318 00:17:02,880 --> 00:17:06,600 Speaker 1: You know, later when we talk about what's in in between, 319 00:17:06,800 --> 00:17:09,679 Speaker 1: like superclusters of galaxies and all we have is energy, 320 00:17:10,080 --> 00:17:12,679 Speaker 1: then I think you'll have to count that. Um. But 321 00:17:12,800 --> 00:17:15,880 Speaker 1: you know, photons are not matter there they are radiation though. 322 00:17:16,640 --> 00:17:20,720 Speaker 1: That's a great good question. So you're saying, within the 323 00:17:20,760 --> 00:17:22,880 Speaker 1: Solar system, the space is still not empty, it's full. 324 00:17:23,000 --> 00:17:25,800 Speaker 1: It's still full of stuff from the Sun. That's right, 325 00:17:25,840 --> 00:17:28,879 Speaker 1: And we should remember that all the stuff that we 326 00:17:28,920 --> 00:17:31,680 Speaker 1: know about everything that's made of atoms, right, that's a 327 00:17:31,720 --> 00:17:35,080 Speaker 1: little fraction of the universe. Right, that's only five of 328 00:17:35,080 --> 00:17:38,200 Speaker 1: all the energy in the universe, and it's about twenty 329 00:17:38,600 --> 00:17:40,600 Speaker 1: of all the matter. The stuff in the universe. The 330 00:17:40,640 --> 00:17:43,480 Speaker 1: rest of it is dark matter, and we and dark 331 00:17:43,520 --> 00:17:46,679 Speaker 1: matter normal matter both cluster into structures like you know, 332 00:17:46,880 --> 00:17:49,800 Speaker 1: planets and galaxies. Whenever those are the structures of normal matter, 333 00:17:50,080 --> 00:17:53,320 Speaker 1: dark matter follows those. So basically you can think of 334 00:17:53,320 --> 00:17:56,320 Speaker 1: it like anywhere you see blobs of matter, there's also 335 00:17:56,440 --> 00:18:00,679 Speaker 1: dark matter there, and about five times as much. So 336 00:18:00,840 --> 00:18:04,720 Speaker 1: there's five million protons, you're saying, there's probably twenty five 337 00:18:04,840 --> 00:18:08,600 Speaker 1: million amount of stuff of dark matter in that in 338 00:18:08,640 --> 00:18:11,280 Speaker 1: that space between planets. Yeah, and then we don't know 339 00:18:11,359 --> 00:18:13,840 Speaker 1: a whole lot about the structure of dark matter. We 340 00:18:13,920 --> 00:18:15,639 Speaker 1: know clumps at the center of the galaxy and then 341 00:18:15,680 --> 00:18:17,959 Speaker 1: spreads out. We don't know how clumpy it is, if 342 00:18:18,000 --> 00:18:21,160 Speaker 1: it's pretty smooth or if it's not. But on average, yeah, 343 00:18:21,160 --> 00:18:23,160 Speaker 1: you can just take the amount of matter and multiplied 344 00:18:23,160 --> 00:18:25,360 Speaker 1: by five, and that's a pretty good estimate for how 345 00:18:25,440 --> 00:18:27,879 Speaker 1: much dark matter there is. Like in this room with 346 00:18:27,960 --> 00:18:30,640 Speaker 1: me right now, you know, in the air I'm breathing, 347 00:18:30,960 --> 00:18:34,120 Speaker 1: there's what ten to the twenty five molecules of air 348 00:18:34,359 --> 00:18:37,600 Speaker 1: right that much mass, there's five times as much dark 349 00:18:37,640 --> 00:18:40,520 Speaker 1: matter in this room per cubic meter with me right now, 350 00:18:40,680 --> 00:18:42,960 Speaker 1: And the same is true out in space. Dark matter 351 00:18:43,000 --> 00:18:45,440 Speaker 1: follows the normal matter. So you can basically just multiply 352 00:18:45,720 --> 00:18:47,520 Speaker 1: the normal matter by five and it tells you how 353 00:18:47,600 --> 00:18:50,520 Speaker 1: much dark matter there is. So there's still a lot 354 00:18:50,520 --> 00:18:54,080 Speaker 1: of stuff out there in the Solar System. The space 355 00:18:54,119 --> 00:18:56,119 Speaker 1: is not quite into but it's sort of really empty 356 00:18:56,200 --> 00:18:58,760 Speaker 1: compared to what we can do on Earth, right, Like 357 00:18:58,960 --> 00:19:01,879 Speaker 1: you're saying, here on Earth, we can you tend, but 358 00:19:01,960 --> 00:19:04,920 Speaker 1: you're staying out in between the Solar System, between planets. 359 00:19:05,240 --> 00:19:07,520 Speaker 1: It's about tend to the six tend to the six, 360 00:19:07,560 --> 00:19:10,200 Speaker 1: which is much better than vacuums on Earth. But it's 361 00:19:10,240 --> 00:19:12,520 Speaker 1: not that small. And in fact, if you're an astronaut 362 00:19:12,920 --> 00:19:15,960 Speaker 1: you need you need like really really good sunscreen because 363 00:19:16,000 --> 00:19:18,639 Speaker 1: it's enough radiation to fry you and give you cancer 364 00:19:18,800 --> 00:19:22,240 Speaker 1: pretty quickly. So the fact that it's not empty has consequences. 365 00:19:22,480 --> 00:19:26,399 Speaker 1: Oh you're saying, if it if it was, if you 366 00:19:26,440 --> 00:19:29,040 Speaker 1: were just out there in a very really thin space, 367 00:19:29,040 --> 00:19:32,040 Speaker 1: suit without a whole lot of protection from radiation, you 368 00:19:32,080 --> 00:19:36,040 Speaker 1: would get fried from that radiation. Wow. So the fact 369 00:19:36,040 --> 00:19:39,399 Speaker 1: that it is pretty empty means that you feel those 370 00:19:39,760 --> 00:19:42,960 Speaker 1: that light from the Sun a lot stronger. Exactly. We 371 00:19:43,040 --> 00:19:45,280 Speaker 1: have an atmosphere between us and the Sun that protects 372 00:19:45,320 --> 00:19:47,240 Speaker 1: us from the solar wind. Right, the solar wind doesn't 373 00:19:47,240 --> 00:19:49,399 Speaker 1: come down to the surface because we're protected by the 374 00:19:49,400 --> 00:19:51,879 Speaker 1: buff or the atmosphere. But out in space you're not 375 00:19:51,960 --> 00:19:54,280 Speaker 1: shielded by that, and so you feel the full brunt 376 00:19:54,320 --> 00:19:57,879 Speaker 1: of the solar solar radiation. And uh, yeah, it's dangerous stuff. 377 00:19:58,000 --> 00:20:01,760 Speaker 1: It's dangerous stuff, is it? There's stuff out there and 378 00:20:01,840 --> 00:20:04,639 Speaker 1: it can kill you. Right, you'll run through traffic, folks. 379 00:20:05,880 --> 00:20:07,520 Speaker 1: It should be the title, right next book, can you 380 00:20:08,040 --> 00:20:11,159 Speaker 1: space traffic? All this stuff they can kill you. Space 381 00:20:11,240 --> 00:20:15,159 Speaker 1: can kill you. Well, let's let's take off from the 382 00:20:15,160 --> 00:20:18,679 Speaker 1: Solar System and let's go into interstellar space. But first 383 00:20:18,760 --> 00:20:33,600 Speaker 1: let's take a quick break. All right, we're talking about 384 00:20:33,600 --> 00:20:37,480 Speaker 1: how empty is space, and we we learned that um 385 00:20:37,520 --> 00:20:41,120 Speaker 1: that inner inner planetary space, like between us and other 386 00:20:41,160 --> 00:20:43,800 Speaker 1: planets in our Solar system, is pretty empty, but not 387 00:20:43,920 --> 00:20:46,680 Speaker 1: quite empty. Right, there's still millions of millions of protons 388 00:20:46,720 --> 00:20:49,880 Speaker 1: and stuff in like a cubic meter of space, right, 389 00:20:50,560 --> 00:20:52,439 Speaker 1: and there's a lot of cubic meters in that space. 390 00:20:52,480 --> 00:20:55,280 Speaker 1: So you're talking a huge amount of particles, Like if 391 00:20:55,280 --> 00:20:57,400 Speaker 1: you have to count them or number them or name them, 392 00:20:57,600 --> 00:20:59,520 Speaker 1: I mean, it's it's too big a number to really 393 00:20:59,560 --> 00:21:02,840 Speaker 1: think about, which, which is sort of strange, is cognitively 394 00:21:02,880 --> 00:21:05,199 Speaker 1: dissended from the fact that we think of it is empty. Right, 395 00:21:05,280 --> 00:21:08,200 Speaker 1: So remember it's just like chok full of particles, right, 396 00:21:08,240 --> 00:21:12,040 Speaker 1: It's like you're swimming in protons and stuff exactly, You're 397 00:21:12,080 --> 00:21:15,280 Speaker 1: literally swimming in it um. But then once you leave 398 00:21:15,359 --> 00:21:18,400 Speaker 1: our Solar system, you go past the heliosphere, and only 399 00:21:18,400 --> 00:21:20,600 Speaker 1: a couple of man made objects have ever done this, 400 00:21:20,720 --> 00:21:23,840 Speaker 1: like the Voyager probes. They've been traveling for decades and 401 00:21:23,880 --> 00:21:28,320 Speaker 1: they finally broke past into like the inter interstellar space, 402 00:21:28,400 --> 00:21:30,240 Speaker 1: like the stuff that the galaxy is made out of. 403 00:21:30,920 --> 00:21:32,960 Speaker 1: So you're saying that the stuff that comes out from 404 00:21:32,960 --> 00:21:35,560 Speaker 1: the Sun, all those protons and ions and stuff, at 405 00:21:35,600 --> 00:21:39,080 Speaker 1: some point kind of doesn't go on forever, right, like 406 00:21:39,119 --> 00:21:41,640 Speaker 1: they maybe they come back because of gravity. Is that 407 00:21:41,760 --> 00:21:43,719 Speaker 1: is that kind of what happens, Like they cluster around 408 00:21:43,960 --> 00:21:46,399 Speaker 1: the Solar system. Well, they Peter out there at the 409 00:21:46,400 --> 00:21:49,240 Speaker 1: intensity gets less and less just because the volume gets 410 00:21:49,280 --> 00:21:52,280 Speaker 1: larger and larger um. And then also they hit the 411 00:21:52,359 --> 00:21:57,040 Speaker 1: interstellar magnetic field, right, what, there's magnetic fields inside the 412 00:21:57,080 --> 00:21:59,800 Speaker 1: galaxy you mean, And and that's different than the one 413 00:21:59,840 --> 00:22:03,359 Speaker 1: we feel inside the solar system. Yeah, because our solar system, 414 00:22:03,400 --> 00:22:05,560 Speaker 1: the magnetic field is dominant by the magnetic field of 415 00:22:05,600 --> 00:22:08,520 Speaker 1: the Sun. Right, And the same way the Earth's magnetic 416 00:22:08,520 --> 00:22:12,280 Speaker 1: field also helps shield us from the solar wind, right, 417 00:22:12,320 --> 00:22:15,080 Speaker 1: the Sun's magnetic field helps shield us from like the 418 00:22:15,119 --> 00:22:20,119 Speaker 1: galactic wind. Whoa h yeah exactly. But then if Peter's 419 00:22:20,160 --> 00:22:22,119 Speaker 1: out right, and you're no longer really protected by the 420 00:22:22,119 --> 00:22:25,280 Speaker 1: Sun's magnetic field, where the point where the Sun's magnetic 421 00:22:25,359 --> 00:22:27,600 Speaker 1: field is about as strong as the magnetic field of 422 00:22:27,640 --> 00:22:30,600 Speaker 1: the galaxy, right, and you're really really far away, and 423 00:22:30,760 --> 00:22:33,760 Speaker 1: so the density of these particles the solar wind is dropping. 424 00:22:34,080 --> 00:22:36,920 Speaker 1: That's when we say you're you're in the interstellar space. 425 00:22:36,960 --> 00:22:40,399 Speaker 1: You've left the heliosphere. So who gives you a certificate 426 00:22:40,440 --> 00:22:45,200 Speaker 1: that at that point you can make your own certificate, 427 00:22:45,200 --> 00:22:48,480 Speaker 1: because you can do anything, because you've accomplished something nobody's 428 00:22:48,520 --> 00:22:51,480 Speaker 1: ever done before. Just bring your own printer and print 429 00:22:51,520 --> 00:22:55,439 Speaker 1: yourself a little certificate. Well, that's probably where the you know, 430 00:22:55,440 --> 00:22:58,400 Speaker 1: our our alien overlords are waiting for us. Oh, I see, 431 00:22:58,440 --> 00:23:00,200 Speaker 1: so you're saying that they're just waiting to I ne 432 00:23:00,359 --> 00:23:03,040 Speaker 1: something as as we step out there. Yeah. Sometimes I 433 00:23:03,080 --> 00:23:05,600 Speaker 1: think that the reason we've never heard from alien species 434 00:23:05,920 --> 00:23:08,840 Speaker 1: is that they're running some massive cosmic zoo, you know, 435 00:23:08,920 --> 00:23:10,800 Speaker 1: and they're just out there watching us, laughing at all 436 00:23:10,800 --> 00:23:12,959 Speaker 1: of our antics. And then all we need to do 437 00:23:13,000 --> 00:23:15,320 Speaker 1: to figure that out and just get out there and 438 00:23:15,640 --> 00:23:17,760 Speaker 1: say hello. And maybe they're like hanging out there waiting 439 00:23:17,760 --> 00:23:19,880 Speaker 1: for us to um, you know, get far enough away 440 00:23:19,880 --> 00:23:22,480 Speaker 1: from our planet that we're really talking to you. They're 441 00:23:22,520 --> 00:23:24,120 Speaker 1: just waiting for us to get put us back into 442 00:23:24,160 --> 00:23:28,280 Speaker 1: our cages. Is that don't make me use the house 443 00:23:29,280 --> 00:23:36,760 Speaker 1: exactly again for the first time. Um. So, if you 444 00:23:36,800 --> 00:23:39,280 Speaker 1: do get out there, if you do get out there 445 00:23:39,320 --> 00:23:42,000 Speaker 1: past our solar system in the in the area dominated 446 00:23:42,000 --> 00:23:43,960 Speaker 1: by the Sun, then you're in what we call the 447 00:23:44,000 --> 00:23:48,720 Speaker 1: interstellar medium. And this is mostly gas. It's like gas 448 00:23:48,840 --> 00:23:51,639 Speaker 1: and a little bit of dust in some cosmic rays. Okay, 449 00:23:51,640 --> 00:23:53,879 Speaker 1: what's the difference between gas and dust? Is it that 450 00:23:54,080 --> 00:23:57,320 Speaker 1: like more complex atoms and stuff. Yeah, dust is like 451 00:23:57,560 --> 00:24:01,199 Speaker 1: pulverized rock, right, So you have the stuff from the 452 00:24:01,240 --> 00:24:05,159 Speaker 1: inside of supernova and old planets that got destroyed and whatever, 453 00:24:05,640 --> 00:24:08,120 Speaker 1: and so yeah, you have like metals and and all 454 00:24:08,160 --> 00:24:11,199 Speaker 1: the silicates and all sorts of stuff. That's what dust is. 455 00:24:11,240 --> 00:24:14,440 Speaker 1: Gas is masic, just hydrogen, right, most of the most 456 00:24:14,440 --> 00:24:16,800 Speaker 1: of the universe is gas, and most of that is hydrogen. 457 00:24:16,920 --> 00:24:19,360 Speaker 1: So it's a proton with electron whizzing around it. Well, 458 00:24:19,440 --> 00:24:22,280 Speaker 1: and what's the concentration at that point? It actually varies 459 00:24:22,320 --> 00:24:24,280 Speaker 1: a lot once you get out of the Solar System 460 00:24:24,320 --> 00:24:27,159 Speaker 1: past the heliosphere. At the high end it's about a 461 00:24:27,240 --> 00:24:30,280 Speaker 1: million molecules per cubic meter, which is just a little 462 00:24:30,280 --> 00:24:33,239 Speaker 1: lower than the density inside the Solar System. But then 463 00:24:33,280 --> 00:24:34,879 Speaker 1: at the low end it goes down to about a 464 00:24:35,000 --> 00:24:38,240 Speaker 1: hundred particles per cubic meter. It's because the galaxy is 465 00:24:38,280 --> 00:24:40,840 Speaker 1: just not that smooth right there, like hot spots and 466 00:24:40,920 --> 00:24:43,639 Speaker 1: cold spots, the spots where it's more dense and spots 467 00:24:43,640 --> 00:24:46,159 Speaker 1: where it's less dense. So it varies between like a 468 00:24:46,240 --> 00:24:49,239 Speaker 1: hundred and a million molecules per cubic meter. In the 469 00:24:49,320 --> 00:24:54,080 Speaker 1: interstellar medium, the spaces between solar systems. Well, here's here's 470 00:24:54,080 --> 00:24:56,200 Speaker 1: a question. How do we know what spaces like out 471 00:24:56,200 --> 00:25:00,680 Speaker 1: there if we've never been there, been there present, that's 472 00:25:00,680 --> 00:25:03,560 Speaker 1: a great question. Well, we haven't been there personally, but 473 00:25:03,640 --> 00:25:08,240 Speaker 1: we have sent for example, the voyager probes, right, um. 474 00:25:08,320 --> 00:25:10,639 Speaker 1: And after that, we have models, right, we have models 475 00:25:10,680 --> 00:25:14,440 Speaker 1: that describe how galaxies are formed and how some how 476 00:25:14,480 --> 00:25:18,280 Speaker 1: stars work and the radiation we expect from them. And 477 00:25:18,359 --> 00:25:22,080 Speaker 1: so we can we can see you know, activity from 478 00:25:22,080 --> 00:25:24,840 Speaker 1: that gas because you know it ionizes or it or 479 00:25:25,040 --> 00:25:28,280 Speaker 1: it deflects light, and so we can probe it even 480 00:25:28,320 --> 00:25:32,800 Speaker 1: without going there, just by seeing like stuff go through it. Right, Okay, cool, 481 00:25:33,359 --> 00:25:35,160 Speaker 1: So we we're sort of guessing in a way. I mean, 482 00:25:35,200 --> 00:25:39,600 Speaker 1: we have models, but we think that's what the emptiness 483 00:25:39,640 --> 00:25:41,280 Speaker 1: is like up there. Yeah. Well, if there was a 484 00:25:41,320 --> 00:25:43,919 Speaker 1: lot more, for example, then we would see more absorption 485 00:25:43,920 --> 00:25:45,520 Speaker 1: of light. If there was a lot less, we would 486 00:25:45,520 --> 00:25:49,600 Speaker 1: see less absorption of light. Remember, gas absorbs photons, and 487 00:25:49,640 --> 00:25:51,560 Speaker 1: so we can have some measure of the gas and 488 00:25:51,560 --> 00:25:54,280 Speaker 1: the dust in our galaxy by just by seeing how 489 00:25:54,400 --> 00:25:57,960 Speaker 1: light is absorbed. So that's kind of the space inside 490 00:25:57,960 --> 00:26:02,240 Speaker 1: the galaxy between star in between solar systems that's that's 491 00:26:02,280 --> 00:26:05,560 Speaker 1: the interstellar medium, that's right. And remember to multiply by 492 00:26:05,560 --> 00:26:08,040 Speaker 1: five for a dark matter because there's a lot of 493 00:26:08,119 --> 00:26:10,680 Speaker 1: dark matter in the galaxy, and the galaxy is mostly 494 00:26:10,760 --> 00:26:13,919 Speaker 1: dark matter, and between the stars is definitely oodles and 495 00:26:13,920 --> 00:26:17,600 Speaker 1: oodles of dark matter on average, right on average. We 496 00:26:17,640 --> 00:26:20,280 Speaker 1: don't really very know very well the distribution. We know 497 00:26:20,359 --> 00:26:22,639 Speaker 1: again it peaks near the center of the galaxy and 498 00:26:22,720 --> 00:26:25,639 Speaker 1: that the amount of dark matter extends past the visible 499 00:26:25,720 --> 00:26:27,719 Speaker 1: edge of the galaxy, but we don't know that much 500 00:26:27,760 --> 00:26:32,040 Speaker 1: about exactly how it's distributed. So pretty empty, it starts 501 00:26:32,040 --> 00:26:34,320 Speaker 1: to drop off exactly once you get out past the 502 00:26:34,400 --> 00:26:36,639 Speaker 1: edge of the Solar System, but still pretty full of 503 00:26:36,800 --> 00:26:45,600 Speaker 1: like dark matter and and in some gas. Right, So, 504 00:26:45,680 --> 00:26:47,440 Speaker 1: now what happens if you keep going that, if you 505 00:26:47,520 --> 00:26:52,320 Speaker 1: keep going past our Solar system, past other solar systems 506 00:26:52,320 --> 00:26:54,840 Speaker 1: and out of the galaxy. What what do we get? 507 00:26:55,080 --> 00:26:57,680 Speaker 1: Well out there between the galaxies is something we very 508 00:26:57,720 --> 00:27:01,960 Speaker 1: cleverly call the intergalactic medium. And um, this is not 509 00:27:02,080 --> 00:27:05,119 Speaker 1: very exciting, and it's basically these it's it's mostly empty, 510 00:27:05,400 --> 00:27:10,400 Speaker 1: it's these strands of of plasma really really really dilute plasma, 511 00:27:10,680 --> 00:27:13,280 Speaker 1: and so it's mostly ionized hydrogen. That's what we mean 512 00:27:13,320 --> 00:27:17,600 Speaker 1: by plasma, and it's on average like one to ten 513 00:27:18,160 --> 00:27:24,439 Speaker 1: molecules of hydrogen per cubic meter. Wow. That so for 514 00:27:24,440 --> 00:27:27,920 Speaker 1: for a cubic meter, which is like a large moving box, right, 515 00:27:28,680 --> 00:27:32,840 Speaker 1: you would only see one to tend atoms of stuff. Yeah, exactly, 516 00:27:33,200 --> 00:27:36,360 Speaker 1: And so that's pretty empty, right. You could like take 517 00:27:36,359 --> 00:27:38,720 Speaker 1: a whole cubic meter and look all around and see 518 00:27:38,760 --> 00:27:42,600 Speaker 1: like one or two or few atoms inside the entire box. 519 00:27:42,680 --> 00:27:46,000 Speaker 1: That's so much more empty than a vacuum here on Earth. 520 00:27:46,840 --> 00:27:50,520 Speaker 1: Between galaxies, is what you're saying. Yeah, exactly, you're between galaxies. 521 00:27:50,960 --> 00:27:52,840 Speaker 1: And the thing that kind of blows my mind about 522 00:27:52,840 --> 00:27:55,760 Speaker 1: this is that, remember, the galaxies are really really really 523 00:27:55,800 --> 00:27:58,720 Speaker 1: far apart. So even though the density of stuff out 524 00:27:58,720 --> 00:28:02,240 Speaker 1: there is almost zero, if you add it all up, 525 00:28:03,000 --> 00:28:06,960 Speaker 1: all the stuff, all the matter between galaxies, a counter 526 00:28:07,080 --> 00:28:12,520 Speaker 1: about half the atoms in the entire universe. What Yeah, 527 00:28:12,640 --> 00:28:15,480 Speaker 1: so like half the atoms in the universe are in galaxies. 528 00:28:15,800 --> 00:28:18,560 Speaker 1: Half the atoms and the universe are not in galaxies. 529 00:28:19,000 --> 00:28:21,120 Speaker 1: And the reason that makes sense is that galaxies are 530 00:28:21,240 --> 00:28:25,159 Speaker 1: tiny compared to the space between galaxies. So if you 531 00:28:25,160 --> 00:28:27,760 Speaker 1: want to fill all the space between galaxies. With even 532 00:28:27,800 --> 00:28:31,280 Speaker 1: a really really low density of molecules, it takes a 533 00:28:31,400 --> 00:28:33,679 Speaker 1: lot of molecules to spread it out. It's like spreading 534 00:28:33,720 --> 00:28:37,320 Speaker 1: your frosting really thin across the cake. Wow, that's amazing 535 00:28:37,680 --> 00:28:40,960 Speaker 1: to think that there's more. There's as much stuff in 536 00:28:41,120 --> 00:28:44,000 Speaker 1: empty space quote unquote what we call empty space as 537 00:28:44,040 --> 00:28:48,920 Speaker 1: there are and like all those black holes and stars, stars, 538 00:28:49,400 --> 00:28:52,840 Speaker 1: the hamsters, hamsters, bananas, half of so much stuff is 539 00:28:52,880 --> 00:28:56,880 Speaker 1: just floating out in this super ultro vacuum. Yeah, exactly. 540 00:28:57,320 --> 00:29:00,560 Speaker 1: And between these galaxies also, we think they're must be 541 00:29:00,640 --> 00:29:03,480 Speaker 1: some dark matter. We don't know because it's really hard 542 00:29:03,480 --> 00:29:05,800 Speaker 1: to see dark matter. Remember, we only see dark matter 543 00:29:05,960 --> 00:29:08,640 Speaker 1: because of its gravitational effects, which means we can only 544 00:29:08,680 --> 00:29:10,680 Speaker 1: really see it when it's pretty dense, like the center 545 00:29:10,680 --> 00:29:13,320 Speaker 1: of a galaxy or a big blob. And so between 546 00:29:13,440 --> 00:29:17,280 Speaker 1: galaxies there might be these filaments there's a rarefied thin 547 00:29:17,360 --> 00:29:19,720 Speaker 1: strands of dark matter, but it's pretty hard to see that. 548 00:29:19,800 --> 00:29:22,800 Speaker 1: We can't see those directly. And again we know this 549 00:29:22,920 --> 00:29:26,080 Speaker 1: because it was if it was not that empty, then 550 00:29:26,160 --> 00:29:28,640 Speaker 1: we wouldn't be able to see other galaxies. So clearly 551 00:29:28,960 --> 00:29:31,120 Speaker 1: that's right, that's how we know, but the composition of 552 00:29:31,160 --> 00:29:35,560 Speaker 1: intergalactic space, because we can measure the absorption of photons 553 00:29:35,600 --> 00:29:37,000 Speaker 1: between here and there, and so we can sort of 554 00:29:37,040 --> 00:29:40,280 Speaker 1: like integrate over here to there and figure out how 555 00:29:40,320 --> 00:29:46,520 Speaker 1: many how much light was absorbed, how clear the spaces? Yeah, yeah, 556 00:29:46,560 --> 00:29:48,520 Speaker 1: And the other interesting thing that happens when you go 557 00:29:48,600 --> 00:29:51,600 Speaker 1: between galaxies is that you have to start to account 558 00:29:51,600 --> 00:29:53,880 Speaker 1: for the other crazy thing in the universe, which is 559 00:29:53,920 --> 00:29:57,880 Speaker 1: the dark energy. Right we said before that matters five 560 00:29:57,920 --> 00:30:00,920 Speaker 1: percent of the stuff in the universe. Dark of matter's 561 00:30:00,960 --> 00:30:04,160 Speaker 1: five times as much as this like of that, the 562 00:30:04,200 --> 00:30:06,160 Speaker 1: rest of it is this thing we call dark energy. 563 00:30:06,360 --> 00:30:08,480 Speaker 1: And the really weird thing about dark energy is that 564 00:30:08,520 --> 00:30:11,600 Speaker 1: it's not clustered at all. Right, Matter it gets pulled 565 00:30:11,600 --> 00:30:14,200 Speaker 1: together by gravity. You get planets and stars and galaxies. 566 00:30:14,480 --> 00:30:19,360 Speaker 1: Dark energy is spread uniformly, right, So it's equally present everywhere, 567 00:30:19,680 --> 00:30:22,040 Speaker 1: right even here with those right now, right right, that's 568 00:30:22,120 --> 00:30:25,200 Speaker 1: right between me and this microphone, between you and your seat, everywhere. 569 00:30:25,720 --> 00:30:29,280 Speaker 1: But because the universe is so big, spreading it uniformly 570 00:30:29,280 --> 00:30:32,120 Speaker 1: means it's not very dense. So, like if you added 571 00:30:32,160 --> 00:30:34,000 Speaker 1: up how much dark energy there is here on Earth 572 00:30:34,120 --> 00:30:36,720 Speaker 1: or in this room with me, there's almost none. But 573 00:30:36,880 --> 00:30:39,120 Speaker 1: once you start getting out there into really really far 574 00:30:39,240 --> 00:30:42,400 Speaker 1: stretches of space where space becomes huge, then it starts 575 00:30:42,480 --> 00:30:45,400 Speaker 1: to take over huge and empty, right, huge and emptier 576 00:30:45,480 --> 00:30:48,640 Speaker 1: and emptier. Exactly right. Yeah, I mean I think what 577 00:30:48,680 --> 00:30:51,400 Speaker 1: you're saying is that out there there's so little stuff 578 00:30:51,600 --> 00:30:55,160 Speaker 1: matter that basically dark energy is like that the main 579 00:30:55,200 --> 00:30:57,560 Speaker 1: thing going on out there. That's right. Once you get 580 00:30:58,040 --> 00:31:01,720 Speaker 1: outside our galaxy and then you get like outside the 581 00:31:01,800 --> 00:31:04,520 Speaker 1: cluster of galaxies that we're in, we're inside this cluster 582 00:31:04,600 --> 00:31:07,240 Speaker 1: of like thirty or fifty galaxies that are all sort 583 00:31:07,240 --> 00:31:09,880 Speaker 1: of orbiting each other, and there's these there's this plasma 584 00:31:09,920 --> 00:31:13,640 Speaker 1: between us, this intergalactic medium, um, this sort of infilaments 585 00:31:13,680 --> 00:31:16,800 Speaker 1: between the galaxies. Once you get past the cluster, then 586 00:31:16,840 --> 00:31:21,560 Speaker 1: you're in inter cluster space, and that's mostly dark energy. 587 00:31:21,720 --> 00:31:24,000 Speaker 1: I'm gonna I'm gonna take a wild guess and say that, 588 00:31:24,240 --> 00:31:28,040 Speaker 1: um guess that you guys call it the intercluster medium. 589 00:31:28,400 --> 00:31:30,960 Speaker 1: That did get that, and you got it right. And again, 590 00:31:31,000 --> 00:31:32,680 Speaker 1: I wish that you had been there the day that 591 00:31:32,680 --> 00:31:34,280 Speaker 1: that name was given, because I'm sure you would have 592 00:31:34,280 --> 00:31:36,880 Speaker 1: come up with a much better name. Um So, so 593 00:31:36,920 --> 00:31:39,440 Speaker 1: out there is mostly just dark energy, because it's really 594 00:31:39,440 --> 00:31:42,520 Speaker 1: sort of is kind of empty space, right, there's no 595 00:31:43,000 --> 00:31:46,520 Speaker 1: not very little stuff. Yeah, exactly. You can't go much 596 00:31:46,560 --> 00:31:49,680 Speaker 1: lower than one atom per cubic meter, right, you start 597 00:31:49,720 --> 00:31:51,760 Speaker 1: to get to like less than an atom per cubic meter. 598 00:31:52,240 --> 00:31:54,880 Speaker 1: And so that's what happens, like out there between the 599 00:31:54,920 --> 00:31:59,640 Speaker 1: clusters of galaxies, the number density of matter drops to 600 00:31:59,680 --> 00:32:02,360 Speaker 1: almost zero. So are you saying that if it drops 601 00:32:02,400 --> 00:32:05,400 Speaker 1: below one atom cubic meter, it means that there are 602 00:32:05,440 --> 00:32:08,320 Speaker 1: some cubic meters that have no atoms. There are definitely 603 00:32:08,360 --> 00:32:11,080 Speaker 1: cubic meters with no atoms. Yeah, if you have point 604 00:32:11,160 --> 00:32:14,280 Speaker 1: one atoms per cubic meter doesn't mean that every cubic 605 00:32:14,320 --> 00:32:16,440 Speaker 1: meter has a tenth of an atom. It means you 606 00:32:16,480 --> 00:32:20,760 Speaker 1: need ten cubic meters too, on average have one atoms, 607 00:32:21,600 --> 00:32:24,880 Speaker 1: which means it's nine of them without it. Okay, So 608 00:32:24,920 --> 00:32:28,240 Speaker 1: that that sounds pretty empty. Isn't that basically empty? It's 609 00:32:28,280 --> 00:32:31,000 Speaker 1: basically empty, But you know it's not totally empty, right, 610 00:32:31,640 --> 00:32:35,000 Speaker 1: and there's always dark energy in there. And the fascinating 611 00:32:35,000 --> 00:32:38,480 Speaker 1: thing to me is that, um, there's no box of 612 00:32:38,480 --> 00:32:43,240 Speaker 1: space that has no energy, right, Space itself always comes 613 00:32:43,240 --> 00:32:46,840 Speaker 1: with dark energy, right, like dark energy makes space and 614 00:32:46,920 --> 00:32:49,480 Speaker 1: space contains dark energy. We don't understand it. We don't 615 00:32:49,480 --> 00:32:51,200 Speaker 1: know what it is. We don't know where it comes 616 00:32:51,200 --> 00:32:53,480 Speaker 1: from or how it's happening, but we know it's there. 617 00:32:54,000 --> 00:32:56,120 Speaker 1: And what that means is that every place in space 618 00:32:56,200 --> 00:32:59,560 Speaker 1: has energy, and energy and mass are not that different. 619 00:32:59,680 --> 00:33:03,200 Speaker 1: Right equals mc squared. So what that means is that 620 00:33:03,320 --> 00:33:06,440 Speaker 1: anywhere there's energy, you can create mass. Like you have 621 00:33:06,480 --> 00:33:09,720 Speaker 1: a little density of energy, it can turn into particles 622 00:33:09,840 --> 00:33:12,719 Speaker 1: very briefly and then turn back into energy. Right. But 623 00:33:12,760 --> 00:33:15,080 Speaker 1: that that's kind of as far as we know, right, 624 00:33:15,080 --> 00:33:18,240 Speaker 1: because you're saying we don't really know that much about 625 00:33:18,320 --> 00:33:20,360 Speaker 1: dark energy. I mean, as far as you know, it 626 00:33:20,400 --> 00:33:24,800 Speaker 1: could maybe have little variations in it, couldn't it. It could. 627 00:33:25,360 --> 00:33:27,720 Speaker 1: The current thinking is that it's uniform, that it's spread 628 00:33:27,760 --> 00:33:30,600 Speaker 1: everywhere through space, that it's a property of space itself. 629 00:33:31,240 --> 00:33:33,800 Speaker 1: But you're right, we're pretty clueless, and so it could 630 00:33:33,840 --> 00:33:35,920 Speaker 1: be the dark energy is totally something different and that 631 00:33:35,960 --> 00:33:38,880 Speaker 1: we're wrong, and it has interesting structure. I suppose that 632 00:33:38,920 --> 00:33:42,160 Speaker 1: would be amazing, But the current thinking is that it's uniform. 633 00:33:42,400 --> 00:33:45,120 Speaker 1: All right, We've gone all the way from the planet 634 00:33:45,160 --> 00:33:48,160 Speaker 1: Earth vacuums and emptyness and planet on planet Earth all 635 00:33:48,160 --> 00:33:52,400 Speaker 1: the way to solar systems and galaxies and intercluster space. 636 00:33:52,760 --> 00:33:55,000 Speaker 1: So let's let's go even beyond that, Daniel, Let's go 637 00:33:55,320 --> 00:34:11,440 Speaker 1: way past that um. But first let's take another break. Okay. 638 00:34:11,480 --> 00:34:15,000 Speaker 1: So we we've gone from the earth emptiness of space 639 00:34:15,040 --> 00:34:18,440 Speaker 1: on Earth, to the Solar System, to the galaxies, to 640 00:34:18,719 --> 00:34:22,240 Speaker 1: inner clusters of galaxies, and we get pretty empty. You're saying, 641 00:34:22,600 --> 00:34:24,879 Speaker 1: you know, maybe less than one atom per cubic meter 642 00:34:25,600 --> 00:34:28,319 Speaker 1: out there between clusters, but you're saying that there's still 643 00:34:28,600 --> 00:34:32,840 Speaker 1: kind of an inherent energy and inherent stuff to space itself. 644 00:34:33,000 --> 00:34:35,480 Speaker 1: That's right. If you zoom out even further, remember that 645 00:34:35,560 --> 00:34:38,120 Speaker 1: clusters form their own kind of clusters that we call 646 00:34:38,280 --> 00:34:43,160 Speaker 1: cleverly superclusters, right, and that these superclusters then form these 647 00:34:43,160 --> 00:34:48,960 Speaker 1: big sheets, these big, these vast stretches which enclose enormous voids, 648 00:34:49,000 --> 00:34:52,320 Speaker 1: so they're really like frothing bubbles right where the edges 649 00:34:52,320 --> 00:34:55,480 Speaker 1: of the bubbles are all these superclusters of clusters of 650 00:34:55,520 --> 00:34:59,640 Speaker 1: galaxies of stars. And to what's inside those voids, well, 651 00:34:59,680 --> 00:35:02,560 Speaker 1: this essentially no matter. I mean, we don't know. We can't, 652 00:35:02,560 --> 00:35:04,920 Speaker 1: like we haven't measured it the way we've measured these 653 00:35:04,920 --> 00:35:07,239 Speaker 1: other things, so we know it's a very very very 654 00:35:07,239 --> 00:35:10,840 Speaker 1: small amount of matter, like a number of protons is tiny. 655 00:35:11,160 --> 00:35:15,000 Speaker 1: But you know there's dark energy there, and there's energy 656 00:35:15,040 --> 00:35:18,080 Speaker 1: in space itself. You know, for example, the Higgs boson 657 00:35:18,560 --> 00:35:22,400 Speaker 1: the Higgs field is something which even if there's no 658 00:35:22,600 --> 00:35:25,279 Speaker 1: particles there, it still has energy. Something we call the 659 00:35:25,360 --> 00:35:29,480 Speaker 1: vacuum expectation value is non zero, like the ground state 660 00:35:29,600 --> 00:35:32,920 Speaker 1: of the Higgs field is not at zero, which means 661 00:35:33,000 --> 00:35:35,719 Speaker 1: this energy in every space and energy can get turned 662 00:35:35,760 --> 00:35:38,799 Speaker 1: into mass. There's this fun thing about quantum mechanics where 663 00:35:38,800 --> 00:35:41,879 Speaker 1: you can create virtual particles. You have energy, you can 664 00:35:41,920 --> 00:35:45,120 Speaker 1: briefly create mass out of it and then back into energy, 665 00:35:45,640 --> 00:35:48,040 Speaker 1: and so that's probably happening everywhere in the universe. You 666 00:35:48,080 --> 00:35:51,080 Speaker 1: take a random box of space inside one of these 667 00:35:51,080 --> 00:35:54,960 Speaker 1: super voids inside the bubble, and briefly particles will be 668 00:35:54,960 --> 00:35:58,759 Speaker 1: being created and then destroyed. But that's a quantum physics thing, right, 669 00:35:58,800 --> 00:36:02,040 Speaker 1: isn't it. Yeah, exactly, that's kantom mechanical. There's this uncertainty 670 00:36:02,400 --> 00:36:06,000 Speaker 1: and this randomness, and some particles are always fluctuating in 671 00:36:06,080 --> 00:36:09,600 Speaker 1: and out of the vacuum. So you're saying, theoretically you 672 00:36:09,719 --> 00:36:12,279 Speaker 1: might be able to have truly empty space, but it's 673 00:36:12,280 --> 00:36:15,719 Speaker 1: sort of not empty all the time forever. Yeah, say 674 00:36:15,719 --> 00:36:18,720 Speaker 1: you like did the painstaking job or removing every single 675 00:36:18,719 --> 00:36:21,400 Speaker 1: particle you found from a cubic meter, then you go 676 00:36:21,440 --> 00:36:22,839 Speaker 1: back to be like, wait a second, I just found 677 00:36:22,840 --> 00:36:25,000 Speaker 1: another particle. What it disappeared? Oh wait, there's another one 678 00:36:25,040 --> 00:36:27,600 Speaker 1: over here. It's sort of like playing quantum Waca mole 679 00:36:28,880 --> 00:36:30,640 Speaker 1: because you can never get all the energy out of 680 00:36:30,680 --> 00:36:33,640 Speaker 1: that box and say you can effectively not ensure that 681 00:36:33,680 --> 00:36:36,640 Speaker 1: there's no matter, right, you can't ensure there's zero matter 682 00:36:36,680 --> 00:36:38,440 Speaker 1: in there because you can't get all the energy out, 683 00:36:38,480 --> 00:36:41,960 Speaker 1: and energy you can always fluctuate back into matter. And 684 00:36:42,120 --> 00:36:45,120 Speaker 1: that's a property you're saying, a property of space itself, 685 00:36:45,160 --> 00:36:49,160 Speaker 1: Like space by itself has energy to it meat we 686 00:36:49,239 --> 00:36:53,360 Speaker 1: need has the propensity to make matter always. Yeah, and 687 00:36:53,440 --> 00:36:56,799 Speaker 1: remember that space is a thing, right, It's not like emptiness. Right, 688 00:36:56,880 --> 00:37:00,279 Speaker 1: Space itself is a thing. It can ripple, it can expand, end, 689 00:37:00,800 --> 00:37:04,640 Speaker 1: it can um, it can bend, and so there's some 690 00:37:04,840 --> 00:37:08,640 Speaker 1: has properties, right, And it's not nothingness. I'm not saying 691 00:37:08,719 --> 00:37:11,600 Speaker 1: nothing has energy. I'm saying space has energy. And we're 692 00:37:11,640 --> 00:37:15,120 Speaker 1: only just now beginning to grapple with what space itself is. 693 00:37:15,800 --> 00:37:19,160 Speaker 1: So if you think space having energy sounds weird, then 694 00:37:19,200 --> 00:37:20,920 Speaker 1: remember that space is a thing. It's like, you know, 695 00:37:21,040 --> 00:37:23,960 Speaker 1: fish scientists swimming through water and discovering that water is 696 00:37:24,000 --> 00:37:27,879 Speaker 1: a thing. Space is definitely a thing that has some energy. Now, 697 00:37:27,920 --> 00:37:32,000 Speaker 1: another deeper question is are there places without space? Right? 698 00:37:32,080 --> 00:37:34,279 Speaker 1: Is there past the edge of the universe? If the 699 00:37:34,320 --> 00:37:37,480 Speaker 1: universe's finite, are there places where there is no space, 700 00:37:38,560 --> 00:37:41,800 Speaker 1: no energy, and therefore no energy. That might be possible, 701 00:37:41,880 --> 00:37:45,520 Speaker 1: but that wouldn't be empty space. That would be emptyness 702 00:37:45,719 --> 00:37:49,719 Speaker 1: or nothingness or something. But that's pretty hard to grapple with, 703 00:37:49,800 --> 00:37:52,399 Speaker 1: you know. Conceptually, you're saying, it's sort of like if 704 00:37:52,400 --> 00:37:56,480 Speaker 1: fish scientists would be like asking having a podcast, a 705 00:37:56,480 --> 00:37:59,600 Speaker 1: couple of fish talking to the podcast, asking themselves it 706 00:38:00,000 --> 00:38:04,120 Speaker 1: and water be empty, and basically the answer is ridiculous 707 00:38:04,160 --> 00:38:06,680 Speaker 1: because we know water is stuff. That's right, And then 708 00:38:06,680 --> 00:38:09,479 Speaker 1: they're having trouble thinking about like is there an edge 709 00:38:09,520 --> 00:38:13,000 Speaker 1: to the pond? Like what's above the surface of the pond? Man, 710 00:38:14,080 --> 00:38:15,799 Speaker 1: what does it mean to not have water? I think 711 00:38:15,800 --> 00:38:17,600 Speaker 1: they would be sort of what they mean by antwer 712 00:38:17,640 --> 00:38:19,600 Speaker 1: would be sort of like, can can you have water? 713 00:38:19,920 --> 00:38:25,359 Speaker 1: Pure water? Right? Like water with noth no, no containmants 714 00:38:25,360 --> 00:38:27,479 Speaker 1: and it just pure h two oh. That that would 715 00:38:27,480 --> 00:38:29,600 Speaker 1: be the question for them that we are sort of asking, 716 00:38:29,840 --> 00:38:32,799 Speaker 1: can if space can be empty? Yeah? Exactly, And then 717 00:38:32,800 --> 00:38:35,120 Speaker 1: the deeper question for them would be can you have 718 00:38:35,480 --> 00:38:39,040 Speaker 1: places without water? And so we would ask can you 719 00:38:39,080 --> 00:38:42,480 Speaker 1: have places without space? Does that even mean anything? And 720 00:38:42,520 --> 00:38:45,279 Speaker 1: that's pretty hard to think about. So I think the 721 00:38:45,320 --> 00:38:48,360 Speaker 1: answer is we're pretty sure you can't have totally empty 722 00:38:48,400 --> 00:38:50,719 Speaker 1: space because of quantum mechanics and dark energy and the 723 00:38:50,760 --> 00:38:56,200 Speaker 1: Higgs Boson vacuum expectation value um, but you might be 724 00:38:56,239 --> 00:38:59,240 Speaker 1: able to have places without space or you know, past 725 00:38:59,280 --> 00:39:01,480 Speaker 1: the edge of the unit verse where her where the 726 00:39:01,480 --> 00:39:04,719 Speaker 1: space ends. But we don't know. That's that part is 727 00:39:05,000 --> 00:39:07,080 Speaker 1: really speculative. And maybe there is a part of the 728 00:39:07,160 --> 00:39:10,640 Speaker 1: universe that is all water with fish scientists asking that 729 00:39:10,880 --> 00:39:14,040 Speaker 1: question where all the podcasts are all wet, and I 730 00:39:14,080 --> 00:39:25,080 Speaker 1: think that their their podcasts are called podcasts. And so 731 00:39:25,200 --> 00:39:27,960 Speaker 1: to recap near the Earth, we have like a few 732 00:39:28,080 --> 00:39:31,200 Speaker 1: million molecules per cubic meter, and then once you get 733 00:39:31,239 --> 00:39:34,160 Speaker 1: outside the Solar system, it drops to like between a 734 00:39:34,239 --> 00:39:38,080 Speaker 1: million and a hundred molecules per cubic meter. Then between 735 00:39:38,160 --> 00:39:40,839 Speaker 1: galaxies it gets down to like one to ten per 736 00:39:40,880 --> 00:39:44,279 Speaker 1: cubic meter. But the emptiest place in space is out 737 00:39:44,320 --> 00:39:48,480 Speaker 1: there in the voids between the bubbles of superclusters, which 738 00:39:48,520 --> 00:39:51,359 Speaker 1: is crazy empty. Well, I guess the question that the 739 00:39:51,440 --> 00:39:54,560 Speaker 1: answer to the question can space be empty? Is yes, 740 00:39:54,920 --> 00:39:57,279 Speaker 1: sort of, but not all the time, or not an 741 00:39:57,320 --> 00:40:01,040 Speaker 1: average or not for long kind of I would say. 742 00:40:01,160 --> 00:40:02,960 Speaker 1: I would say most of the space we see is 743 00:40:03,000 --> 00:40:05,520 Speaker 1: not empty, and as you get further out, it gets 744 00:40:05,520 --> 00:40:08,480 Speaker 1: emptier and emptier and emptier to get pretty empty, but 745 00:40:08,680 --> 00:40:14,000 Speaker 1: never totally truly empty, but but not not all the time, right, Like, um, 746 00:40:14,080 --> 00:40:16,880 Speaker 1: you could my mic get a cubing meter with nothing, 747 00:40:16,920 --> 00:40:21,080 Speaker 1: absolutely nothing in it, no matter, but before long you'll 748 00:40:21,120 --> 00:40:24,080 Speaker 1: see matter popping in and out all the time. Yeah, 749 00:40:24,120 --> 00:40:26,840 Speaker 1: before long, meaning like ten of the twenty three seconds. 750 00:40:26,920 --> 00:40:33,280 Speaker 1: So congratulations in your accomplishments. That's that's what my grandma 751 00:40:33,280 --> 00:40:37,279 Speaker 1: would call it. A Panamanian minute. Okay, I don't know 752 00:40:37,280 --> 00:40:39,799 Speaker 1: what that means, but it sounds awesome, all right. I 753 00:40:39,840 --> 00:40:43,799 Speaker 1: hope that podcast filled your space with interesting knowledge and 754 00:40:43,840 --> 00:40:45,919 Speaker 1: ideas to think about. That's right, I hope we blew 755 00:40:45,960 --> 00:40:48,800 Speaker 1: your mind and injected some space in there. And remember 756 00:40:48,800 --> 00:40:52,879 Speaker 1: that we live in a vast universe filled mostly with nothing, yeah, 757 00:40:53,440 --> 00:40:56,719 Speaker 1: except on the in the space around you, So take 758 00:40:56,800 --> 00:40:59,480 Speaker 1: some time to appreciate all this stuff around you because 759 00:40:59,600 --> 00:41:02,000 Speaker 1: it could be pretty empty out there, all right. Thanks 760 00:41:02,000 --> 00:41:04,440 Speaker 1: everyone for listening, and if you have questions, send them 761 00:41:04,480 --> 00:41:08,240 Speaker 1: to feedback at Daniel and Jorge dot com. Thanks for listening, 762 00:41:08,520 --> 00:41:18,480 Speaker 1: see you next time. If you still have a question 763 00:41:18,480 --> 00:41:21,919 Speaker 1: after listening to all these explanations, please drop us a line. 764 00:41:21,960 --> 00:41:24,120 Speaker 1: We'd love to hear from you. You can find us 765 00:41:24,120 --> 00:41:27,920 Speaker 1: at Facebook, Twitter, and Instagram at Daniel and Jorge That's 766 00:41:27,960 --> 00:41:31,319 Speaker 1: one word, or email us at feedback at Daniel and 767 00:41:31,440 --> 00:41:34,880 Speaker 1: Jorge dot com. Thanks for listening and remember that Daniel 768 00:41:34,920 --> 00:41:37,440 Speaker 1: and Jorge Explain the Universe is a production of I 769 00:41:37,680 --> 00:41:41,120 Speaker 1: Heart Radio. From more podcast from my Heart Radio visit 770 00:41:41,160 --> 00:41:44,640 Speaker 1: the I Heart Radio app, Apple Podcasts, or wherever you 771 00:41:44,719 --> 00:41:46,240 Speaker 1: listen to your favorite shows.