Latest / Daniel and Kelly’s Extraordinary Universe / Could life have started much earlier in the Universe?

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Could life have started much earlier in the Universe? · Daniel and Kelly’s Extraordinary Universe

0:08
Speaker 1: Hey, Katie, how's the weather over there? It's a little
0:11
Speaker 1: cold now that winter is coming. Well, would you say
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Speaker 1: it's still habitable? I mean humans can survive over there.
0:17
Speaker 1: I moved to Italy, not to Antarctica. Well, you know,
0:21
Speaker 1: compared to southern California, basically every place that has a
0:24
Speaker 1: winter is functionally Antarctica. That's pretty true. I have a
0:28
Speaker 1: thick winter survival coat and flares and a bunch of huskies,
0:34
Speaker 1: and everyone else is still in their sweaters and scarves.
0:37
Speaker 1: So I wonder if that means that people like us
0:40
Speaker 1: from southern California wouldn't make good Martian colonists. I think
0:44
Speaker 1: if they had a Martian in an out burger, people
0:47
Speaker 1: from l A would be flocking to Mars. Maybe that's
0:51
Speaker 1: a good way to reduce the traffic here in l A. Hi.
1:08
Speaker 1: I'm Daniel. I'm a professor at UC Irvine and a
1:11
Speaker 1: particle physicist, and I almost never drive in traffic in
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Speaker 1: l A. My name is Katie Golden, and I'm the
1:18
Speaker 1: host of Creature Feature, and I love bumper to bumper
1:22
Speaker 1: traffic so I can read all those cool bumper stickers
1:25
Speaker 1: you guys have. Do you ever get stuck behind a
1:27
Speaker 1: car that has enough reading material to really get you
1:30
Speaker 1: through your commute. Yeah, I mean it's like it's a
1:32
Speaker 1: whole journey, especially when they paper different political views on
1:36
Speaker 1: the back of the bumper and I try to invent
1:38
Speaker 1: a whole interesting story for this individual. Man. How do
1:41
Speaker 1: people even survive traffic before podcasts? And Welcome to the
1:45
Speaker 1: podcast Daniel and Jorge explain the universe in which we
1:49
Speaker 1: navigate the traffic of the universe to give you ideas
1:52
Speaker 1: about how everything works. We talk about the biggest stuff
1:56
Speaker 1: in the universe, the neutron stars, the black holes, the
1:58
Speaker 1: formations of galaxy. We talked about the earliest stuff in
2:01
Speaker 1: the universe all the way back to the Big Bang.
2:04
Speaker 1: We talked about how the universe will end. We don't
2:06
Speaker 1: shy away from any question on this podcast. We dig
2:09
Speaker 1: into it, we open it up, we spread it all
2:11
Speaker 1: around on toast, and we serve it to you. And
2:14
Speaker 1: my friend and co host Jorge is on a break today,
2:17
Speaker 1: so we are very happy to have our regular and
2:20
Speaker 1: wonderful guest host, Katie. Katie, thanks very much for joining
2:22
Speaker 1: us today. Always a pleasure to be here and to
2:25
Speaker 1: look into the mysteries of the universe. You said, I
2:29
Speaker 1: could ask any question right, no matter what, no matter what,
2:33
Speaker 1: no matter what. But now you got me a little scared.
2:36
Speaker 1: I want to know when the first butt appeared in
2:38
Speaker 1: the universe. Do you mean the first behind or the
2:43
Speaker 1: first Yeah, the first behind, the first tushy? Is that
2:47
Speaker 1: not appropriate you said anything? I think that's a deep
2:49
Speaker 1: interesting question about the nature of the universe. And you know,
2:53
Speaker 1: was that a good looking but or not? Like you know,
2:55
Speaker 1: did butts evolved and then people learned to appreciate them
2:58
Speaker 1: or was it the other way around? What came first,
3:00
Speaker 1: the chicken or the butt? You know, I don't know
3:03
Speaker 1: the answer to that question, so off the bat, you've
3:06
Speaker 1: already stumped me. But it does open up a whole
3:08
Speaker 1: other genre of questions about first, you know, when things
3:12
Speaker 1: first happened in the universe, because I think people see
3:16
Speaker 1: sometimes the history of the universe as inevitable, like the
3:19
Speaker 1: universe started dot dot dot. We are here. But you
3:22
Speaker 1: have to remember that there's lots of potential paths for
3:25
Speaker 1: the universe. There's quantum randomness at the beginning of the
3:28
Speaker 1: universe that massively influenced the entire shape and structure of
3:31
Speaker 1: the universe. Why we have galaxies here, Why we don't
3:34
Speaker 1: have galaxies there? The universe could have been very different
3:37
Speaker 1: from the universe that we have today. So it's really
3:40
Speaker 1: interesting to ask questions about the first time something happened
3:43
Speaker 1: because it gives you a glimpse into how the universe
3:45
Speaker 1: might have been. How likely do you think it would
3:48
Speaker 1: have been that Earth never formed? Like, is it really
3:53
Speaker 1: lucky that Earth happened at all? Or was that something
3:56
Speaker 1: that seemed bound to happen. Yeah, that depends a little
3:59
Speaker 1: bit on what you do find Earth. You know, the
4:01
Speaker 1: exact details of the Earth, the way it is with
4:04
Speaker 1: people on it and their butts in their particular shape
4:06
Speaker 1: and people having podcasts. You know, it's essentially infinitesimal, right,
4:10
Speaker 1: It's almost zero. And the other thing to remember is
4:13
Speaker 1: that the Earth hasn't been around during most of the universe.
4:17
Speaker 1: Universe is like fourteen billion years old. The Earth is
4:20
Speaker 1: only four or five billion years old, so most of
4:23
Speaker 1: the history of the universe was earthless. So where would
4:28
Speaker 1: we go then in that kind of universe? Like, do
4:31
Speaker 1: you think there are other earths out there that we
4:34
Speaker 1: could just PLoP our keysters right down on? Are Are
4:36
Speaker 1: we pretty fortunate to have our Earth. It's still an
4:39
Speaker 1: open question in science, you know, what those other planets
4:42
Speaker 1: are like and how earthlike there are. We talked on
4:45
Speaker 1: the podcast before about what other planets might be out there,
4:49
Speaker 1: and in the last twenty years or so, we've actually
4:51
Speaker 1: seen planets around other stars and even found a few
4:55
Speaker 1: that seemed to be earthlike. But you know, by earthlike
4:58
Speaker 1: we basically just mean a hockey planet that's close enough
5:01
Speaker 1: to its star that has enough warmth to melt ice.
5:05
Speaker 1: We don't really know what those planets are like, so
5:07
Speaker 1: we don't know if there are a lot of Earth's
5:09
Speaker 1: out there teeming with life, or if we really do
5:12
Speaker 1: have a very very special home in the universe. We
5:15
Speaker 1: cannot attest to the quality of these off brand Earth.
5:20
Speaker 1: Sometimes the generics are even better than the original, you know,
5:24
Speaker 1: certainly cheaper. But it makes me wonder could Earth have
5:27
Speaker 1: formed earlier in the universe, because you know, the universe
5:30
Speaker 1: is expanding rapidly and now things are further and further
5:33
Speaker 1: apart than they used to be, and so if we
5:35
Speaker 1: had been around five billion years ago, we could have
5:38
Speaker 1: seen a very different kind of night sky. We could
5:42
Speaker 1: have learned different things about the universe. If we've been
5:44
Speaker 1: around in an earlier epoch makes me wonder like would
5:47
Speaker 1: have been possible for Earth to form five billion years ago?
5:52
Speaker 1: And it raises really interesting questions like could there have
5:54
Speaker 1: been alien civilizations that, you know, a rose lived and
5:58
Speaker 1: then burned themselves, all billions of years before life even
6:02
Speaker 1: started on Earth. What would you see in the night
6:05
Speaker 1: sky like staring up from this early version of Earth. Well,
6:09
Speaker 1: the universe is expanding, and that expansion is accelerating, so
6:13
Speaker 1: as time goes on, we can see a smaller and
6:16
Speaker 1: smaller portion of the universe. Of course, we don't know
6:20
Speaker 1: how big the universe is at all, so we don't
6:22
Speaker 1: know what portion we're seeing. But as time goes on,
6:25
Speaker 1: things fall off the edge of the observable universe because
6:28
Speaker 1: it's expanding faster than the speed of light. So five
6:32
Speaker 1: billion years ago we could see more galaxies, and before
6:35
Speaker 1: that we could see even more stuff. And so if
6:38
Speaker 1: we've been around very early in the history of the universe,
6:40
Speaker 1: we could see things that are now invisible and that
6:43
Speaker 1: no human might ever see. So would the sky just
6:46
Speaker 1: be dotted with stars and galaxies or even black holes
6:50
Speaker 1: that we're not even aware of or never will be
6:52
Speaker 1: aware of. We don't know what that night sky would
6:55
Speaker 1: have held because we will never see what's there. It's
6:59
Speaker 1: gone for ever we missed it. It's like we showed
7:01
Speaker 1: up for the second season of the Universe TV show
7:04
Speaker 1: and somebody deleted the first season. It's just gone. I
7:07
Speaker 1: have this cosmic case of foma right now that I
7:10
Speaker 1: cannot even begin to describe how frustrating it is. But
7:13
Speaker 1: in order to ask these questions about the universe, in
7:15
Speaker 1: order to look up at the night sky and wonder
7:18
Speaker 1: what's out there, you need to have somebody alive, somebody
7:21
Speaker 1: intelligent to do that observing. And so that leads us
7:24
Speaker 1: to wonder about when that could first happen, When you
7:27
Speaker 1: could first have sort of intelligent beings gazing up at
7:30
Speaker 1: the universe scribbling down notes. Yeah, I mean it seems
7:34
Speaker 1: like as long as you have some kind of conditions
7:38
Speaker 1: that could have life, right, Like I would be happy
7:41
Speaker 1: guessing like, Okay, if you you can't have the conditions,
7:44
Speaker 1: let's just assume that maybe life could take hold there.
7:47
Speaker 1: But from what you're describing, this is a lot more
7:51
Speaker 1: of a chaotic situation than what we might think. Absolutely,
7:55
Speaker 1: there's lots of stuff to dig into there, and so
7:57
Speaker 1: today on the podcast we'll be asking question when is
8:06
Speaker 1: the earliest life could have started in the universe? And
8:10
Speaker 1: I think what you just said is really interesting, something
8:12
Speaker 1: about how assuming if the bits are in place, that
8:15
Speaker 1: life will start. I don't think that's necessarily a guarantee,
8:19
Speaker 1: but based on our planet Earth and how life seems
8:23
Speaker 1: to be so tenacious and end up popping up basically
8:29
Speaker 1: anywhere that it can find a niche, I think there
8:32
Speaker 1: is a good chance that as long as you have
8:33
Speaker 1: the ingredients for life and enough time, which that is key, obviously,
8:38
Speaker 1: it has a pretty good chance of happening. But this
8:42
Speaker 1: is all conjecture, and I mean, I'm curious what other
8:45
Speaker 1: people think about what's going on and how life could
8:48
Speaker 1: have started. It is conjecture, but I like hearing your
8:51
Speaker 1: point of view. You seem to be sort of a
8:53
Speaker 1: cheerleader for life. You're like, come on, life, you can
8:55
Speaker 1: do it. You have the materials. I believe in you.
8:57
Speaker 1: I'm standing by a little bean sprout with a couple
9:00
Speaker 1: of cheerleading pom poms and you're like, go, go, you
9:02
Speaker 1: can do it. If you can't do it, then I
9:04
Speaker 1: don't know. I guess for a lot in the universe. Well,
9:07
Speaker 1: it does seem sad, sort of an empty if the
9:09
Speaker 1: universe exists with all the materials for life, but it
9:11
Speaker 1: just sort of doesn't come together and get started. So,
9:15
Speaker 1: as usual, I was wondering what people out there on
9:17
Speaker 1: the Internet thought about when the earliest life could have
9:21
Speaker 1: begun in the universe. So I reached out to our
9:23
Speaker 1: listeners who were happy to volunteer to answer questions. These
9:27
Speaker 1: listeners have had no chance to prepare their answer. They
9:30
Speaker 1: just responded spontaneously, so we could get a sense for
9:33
Speaker 1: what people are thinking and what they already know. If
9:36
Speaker 1: you'd like to participate for a future episode, please don't
9:39
Speaker 1: be shy. Right to me two questions at dangel and
9:42
Speaker 1: Jorge dot com and you can hear your off the
9:44
Speaker 1: cuff speculation on the podcast. So before you hear these answers,
9:48
Speaker 1: things to yourself. When do you think is the earliest
9:51
Speaker 1: moment life could have begun in the universe? I'm going
9:54
Speaker 1: to say at least earlier than last Wednesday. And that's
9:59
Speaker 1: from a bio largest folks, right there, she's an authority.
10:02
Speaker 1: All right, here's what people had to say the first stars.
10:07
Speaker 1: We're really just hydrogen and helium, which is not enough
10:12
Speaker 1: to have generated life based components. So I would say
10:18
Speaker 1: we would need at least second generation stars in order
10:22
Speaker 1: to have heavier elements involved. Well, I assume that life
10:26
Speaker 1: would need an energy source like we have the Sun.
10:29
Speaker 1: So my guests would be that the first life formed
10:32
Speaker 1: shortly after the first stars did. I'm not quite sure
10:35
Speaker 1: when that was, so if I had to guess, I
10:37
Speaker 1: would say maybe five million years after the Big Bang.
10:41
Speaker 1: I know the Earth went through a period of heavy
10:43
Speaker 1: bombardment and we couldn't have had life then, you know that,
10:46
Speaker 1: So yeah, I think it has to be pretty stable,
10:48
Speaker 1: but I don't know when the earliest that would have
10:52
Speaker 1: happened in the universe. Oh, let's define life. I would
10:57
Speaker 1: define life as of the first molecules, and I would
11:03
Speaker 1: guess that would be in the first billion years since
11:08
Speaker 1: the universe began. I would say that maybe somehow life
11:14
Speaker 1: could have developed when the universe kind of became cool
11:17
Speaker 1: enough for it and transparent, so maybe it could have
11:21
Speaker 1: been around three I think that's about three thousand years
11:24
Speaker 1: after the Big Bang is when we first got the
11:26
Speaker 1: cosmic micreer background radiation. So maybe somehow in that soup.
11:31
Speaker 1: There could have been at least you know, single self
11:34
Speaker 1: life or something along those lines. I think that the
11:37
Speaker 1: earliest life in the universe may have been some kind
11:41
Speaker 1: of extraterrestrial in some other galaxy. I don't think the
11:47
Speaker 1: life become here in there, life as we know it,
11:51
Speaker 1: or life in general. Well, um, I would say life
11:56
Speaker 1: in general in some exotic form, and depending what you
12:00
Speaker 1: consider life, if complex, you know, self replicating proteins are,
12:05
Speaker 1: life might have started fairly early on within I don't
12:09
Speaker 1: know how to do do a million years or so at
12:13
Speaker 1: since the beginning of the universe, but life as we
12:15
Speaker 1: know it takes a long time to evolve. I would
12:17
Speaker 1: say that requires at least some small number of billions
12:21
Speaker 1: of years. I thought that was really interesting. These are
12:26
Speaker 1: really smart guesses. It seems like people are basing their
12:30
Speaker 1: guesses on what they think to be going on with
12:34
Speaker 1: the early universe in terms of how chaotic it is,
12:37
Speaker 1: you know, what the chemical composition of stars are. But
12:41
Speaker 1: it's also interesting to hear about what people consider to
12:44
Speaker 1: be early in the universe. You know, somebody says pretty
12:47
Speaker 1: early the first billion years. It's like, wow, man, a
12:51
Speaker 1: billion years is a long time to wait like, if
12:53
Speaker 1: I invite you to party at my house and you're
12:55
Speaker 1: a billion years late, do you consider yourself still pretty early?
12:59
Speaker 1: I mean, I think it's fashionable, right, I don't know etiquette.
13:04
Speaker 1: That's probably different over there in Italy also, Dad, But
13:07
Speaker 1: it gives you a sense of just the cosmic scope here.
13:10
Speaker 1: And you know, it's really hard to get your mind
13:12
Speaker 1: around the length of time we're talking about. Even human
13:16
Speaker 1: history is difficult to imagine. You know, think about what
13:18
Speaker 1: it was like to live five thousand years ago. I
13:21
Speaker 1: think about all the people that have lived between now
13:24
Speaker 1: and then, all the times they woke up, all the
13:26
Speaker 1: times they scratched their heads, all the arguments, the marriages,
13:29
Speaker 1: the divorces, you know, the triumphs and disappointments. That's an
13:33
Speaker 1: incredible amount of time. And that's just like the tiniest
13:36
Speaker 1: slice of the time the humans have been on Earth.
13:39
Speaker 1: All right, I'm cross eyed. Now. We can't keep on
13:42
Speaker 1: doing this. It seems like a whole heck of a
13:45
Speaker 1: lot of stuff cosmically can be going on in a
13:48
Speaker 1: billion years? Or is that nothing to a star? Exactly
13:52
Speaker 1: a billion years is a very long time for us,
13:55
Speaker 1: but for the universe, it's just a little slice of
13:58
Speaker 1: all the time that has happened. So, you know, try
14:01
Speaker 1: to like get your mind around a million years, a
14:04
Speaker 1: billion years. I don't even know if it's possible to do,
14:07
Speaker 1: you know, I guess maybe thinking about billionaires, like think
14:10
Speaker 1: about Jeff Bezos and Elon Musk how much money they
14:13
Speaker 1: have compared to how much money you have. And I'll
14:16
Speaker 1: give you a sense for like the amount of time
14:19
Speaker 1: we're talking about. I do think about that a lot.
14:22
Speaker 1: But so in these early stages of the universe, we
14:25
Speaker 1: have these vast periods of time that seemed just incalculable
14:31
Speaker 1: to humans. But in terms of what's going on with
14:35
Speaker 1: the universe, are there things happening there that would be,
14:39
Speaker 1: in your opinion, prohibitive to life, say, in like the
14:42
Speaker 1: first billion years of the universe's lifespan. Absolutely, in the
14:48
Speaker 1: very beginning of the universe, things were pretty hot and crazy.
14:51
Speaker 1: You know. I think we'll get into it a little
14:52
Speaker 1: bit more later, but the first moments of the universe,
14:56
Speaker 1: for example, the universe was very dense and very very hot.
14:59
Speaker 1: You know, you talking about like the inside of a star,
15:02
Speaker 1: very high temperatures, very high density, crazy interactions constantly. It's
15:07
Speaker 1: hard to imagine life as we know it existing at
15:11
Speaker 1: least in the very early universe. Yeah, I know some
15:13
Speaker 1: very dense and hot people too. But you know, maybe
15:16
Speaker 1: we should start with thinking about what life needs with
15:20
Speaker 1: the typical conditions are for life as we know it,
15:23
Speaker 1: and then we can figure out when those things occurred
15:25
Speaker 1: in the universe. Oh yeah, I kind of know this one,
15:28
Speaker 1: at least in terms of the biological aspects of life.
15:33
Speaker 1: You need water, that's super important. You need some kind
15:37
Speaker 1: of energy which can be converted into energy that life
15:42
Speaker 1: can use. Like I said earlier, you you need some
15:45
Speaker 1: time for this to be able to happen, sort of
15:49
Speaker 1: like baking. You can't put all the ingredients for a
15:51
Speaker 1: cake into the oven, take it out after a minute
15:54
Speaker 1: and expect anything other than a chocolate soup. There's no
15:57
Speaker 1: like microwave version of the university can say like zapp
16:00
Speaker 1: life into existence, right my microwave brownie version of the
16:04
Speaker 1: primordial soup. And energy often will mean like something like
16:08
Speaker 1: our our son gives the Earth energy. You need there
16:11
Speaker 1: to be things that are not too like enough chemicals
16:15
Speaker 1: going on that can help create these protein chains, or
16:18
Speaker 1: maybe even something that is different from how our carbon
16:21
Speaker 1: based life form is on Earth, but certainly you would
16:25
Speaker 1: need a little bit of stability as well, otherwise the
16:29
Speaker 1: chaos and entropy is just gonna knock everything down like
16:32
Speaker 1: a bunch of dominoes. So from a physics point of view,
16:35
Speaker 1: needing an energy source like a star to keep you
16:37
Speaker 1: warm makes perfect sense. And you need, you know, a
16:40
Speaker 1: surface to get to the right temperature, and you need
16:42
Speaker 1: enough time. All that makes sense to me as a physicist.
16:44
Speaker 1: What about the materials though, you were talking about for biochemistry,
16:48
Speaker 1: Like what elements do you need and why do you
16:50
Speaker 1: need them? Like why do we have carbon and oxygen
16:52
Speaker 1: and nitrogen? Why do we need all of those elements
16:55
Speaker 1: to make life? Why couldn't we have assembled it out
16:57
Speaker 1: of just helium and hydrogen. I mean, my under standing
17:00
Speaker 1: of it is that carbon is such a powerful base
17:05
Speaker 1: for life based on how these molecules can connect to
17:09
Speaker 1: one another. You have carbon with its four little arms
17:13
Speaker 1: that can connect and form all sorts of good molecules
17:16
Speaker 1: that can be used for a variety of things that
17:19
Speaker 1: life needs. So you need at least are kind of
17:22
Speaker 1: earth based. Life needs protein chains to create the d
17:28
Speaker 1: n A that is the basic building blocks of all life.
17:32
Speaker 1: You need some kind of complex molecule that you can
17:36
Speaker 1: create and recreate in order to be a blueprint for
17:41
Speaker 1: creating an organism. Otherwise, if you can't have these bonds
17:46
Speaker 1: that you can easily create and then rearrange and build basically,
17:50
Speaker 1: like you know, when you think of legos or connects
17:54
Speaker 1: or whatever you're building thing is of choice. You need
17:57
Speaker 1: atoms that are capable of make these connections and being
18:01
Speaker 1: built in such a way that is conducive to forming
18:04
Speaker 1: something like proteins that are used in DNA. I mean,
18:07
Speaker 1: that's that's my limited understanding of atomic scale biology. Well,
18:13
Speaker 1: the lego example makes a lot of sense to me.
18:15
Speaker 1: If somebody just gave you a pile of legos and
18:17
Speaker 1: they were only just those little thin one pieces, you
18:20
Speaker 1: couldn't really build anything because all you can do is
18:22
Speaker 1: like stack them on top of each other. You can't
18:24
Speaker 1: connect them to other pieces very easily. And if you
18:26
Speaker 1: want to make something more complex, you need some larger
18:28
Speaker 1: pieces that you can use to like build out a
18:31
Speaker 1: backbone and extrapolate from and build other elements. And so
18:34
Speaker 1: that makes a lot of sense to me that you
18:36
Speaker 1: just need like complex enough bits in order to make
18:39
Speaker 1: the complexity we have in our life. So our list
18:42
Speaker 1: of requirements so far is like an energy source for
18:45
Speaker 1: some warmth, some raw materials with enough complexity in them,
18:49
Speaker 1: and then just enough time. Yeah, and I think the
18:51
Speaker 1: time thing seems pretty important when we're considering the age
18:56
Speaker 1: of the universe, because if you have a really chao
19:00
Speaker 1: addic system, that's going to cut down on your time
19:02
Speaker 1: for anything to happen, right Like, if you have a
19:04
Speaker 1: planet that's being constantly smacked in the face with meteors,
19:09
Speaker 1: it's not going to give whatever life could potentially form
19:13
Speaker 1: on the surface enough time to even form before it
19:16
Speaker 1: gets just obliterated into more star dust. Absolutely, So I
19:20
Speaker 1: want to talk about when that might have all come
19:23
Speaker 1: together in the early universe, how long it took to
19:25
Speaker 1: assemble all those bits and give it a time to
19:28
Speaker 1: cook around and turn into something yummy and fun and hilarious.
19:32
Speaker 1: But first, let's take a quick break. All right, we're
19:47
Speaker 1: back and we're talking about how early butts could have
19:51
Speaker 1: formed in the universe, or at least when life could
19:55
Speaker 1: have started. And we're casting our minds back well before
19:58
Speaker 1: life on Earth, well before our solar system started. We're
20:02
Speaker 1: going deep, deep, back into the history of the universe
20:05
Speaker 1: fourteen billion years ago. To think about that first moment
20:09
Speaker 1: when life might have started, and not just as a
20:11
Speaker 1: way to explore like what an alternative version of us
20:14
Speaker 1: could have been, but there could be life out there
20:17
Speaker 1: that began in the very early universe. There could be
20:19
Speaker 1: civilizations potentially that began in the very first few moments
20:23
Speaker 1: that life was possible and could now be billions of
20:27
Speaker 1: years old. Think about how hilarious their podcasts must be
20:30
Speaker 1: by now, And why haven't they given me a call yet?
20:33
Speaker 1: You know, not even Nina, Well, you know, it just
20:35
Speaker 1: takes time. They want your podcast career to like marinate
20:38
Speaker 1: for another million years or so, then they'll give you
20:40
Speaker 1: a call. Maybe they're offended because I only cover Earth
20:43
Speaker 1: animals and I haven't covered like bisoork To animals on
20:48
Speaker 1: their planet of bisk To. I don't know how your
20:51
Speaker 1: advertisers would would feel about these topics. I don't know
20:55
Speaker 1: if the people on Bisok really buy anything so new
20:58
Speaker 1: plim Yeah, I can see how that's a problem. So Okay,
21:01
Speaker 1: we talked about the ingredients we need right like warmth,
21:05
Speaker 1: We need the right materials, like we need water, we
21:08
Speaker 1: need various chemical compositions to be able to make building
21:12
Speaker 1: blocks like DNA. And we need the right temperature, right, Like,
21:17
Speaker 1: it can't be too hot and it can't be too cold.
21:19
Speaker 1: When it's too cold, things are really slow, right, And
21:22
Speaker 1: if it's too hot, things are way too fast. Right.
21:26
Speaker 1: And I'm sure there are people out there wondering, like, hey,
21:29
Speaker 1: why are you guys just talking about life as we
21:31
Speaker 1: know it. Well, we'll get there, we'll talk about other
21:33
Speaker 1: crazy forms of life, but let's at least begin with
21:36
Speaker 1: the kind of life that we're thinking about. So first
21:38
Speaker 1: up on that list of ingredients is warmth. Right, we
21:41
Speaker 1: need a star. Essentially, we need something to heat us.
21:44
Speaker 1: And in the very early universe, of course, there were
21:47
Speaker 1: no stars. Things were very hot and dense. It was
21:49
Speaker 1: all sort of like the inside of a star. But
21:52
Speaker 1: then things expanded rapidly and things started to cool down,
21:56
Speaker 1: and after about three eight thousand years, all the articles
22:00
Speaker 1: that were flying around settled down into elements, they neutralized,
22:04
Speaker 1: and then you just have these vast clouds of gas,
22:07
Speaker 1: almost exclusively hydrogen and helium. So vast clouds of gas,
22:12
Speaker 1: and yet no butts yet. Interesting, so far, zero buts
22:16
Speaker 1: in the universe. It's a butt cream universe so far,
22:19
Speaker 1: and those clouds of gas are just sort of like
22:21
Speaker 1: cold and floating out there, and some pockets of them
22:24
Speaker 1: are a little denser than other pockets because of quantum
22:27
Speaker 1: fluctuations in the early universe, and those very gradually start
22:31
Speaker 1: to gather together because if you have one bit that's
22:34
Speaker 1: a little denser, then it has more gravity than the
22:37
Speaker 1: other bits, and so it wins the tug of war
22:39
Speaker 1: and starts attracting more atoms of those gases and more
22:43
Speaker 1: and more and more, and eventually you coalesce enough of
22:46
Speaker 1: them that you can get enough gravitational pressure that stars
22:50
Speaker 1: can start to form and burn. But it's not a
22:52
Speaker 1: very quick process because gravity is super duper weak. You know,
22:56
Speaker 1: the gravity of Earth is pretty weak. You can overpower
23:00
Speaker 1: just with like your legs. You're overpowering the entire gravity
23:03
Speaker 1: of the whole planet. Yeah, but if you try to
23:06
Speaker 1: overpower the gravity to get into space, that's kind of difficult, right.
23:10
Speaker 1: So why isn't it easier to get a rocket into
23:13
Speaker 1: space if gravity is so weak. That's just because you
23:16
Speaker 1: have nothing to push against. If you had a ladder,
23:18
Speaker 1: you could definitely climb up into space and it would
23:20
Speaker 1: get easier and easier as you got higher and higher.
23:23
Speaker 1: So really the only reason it's hard to get out
23:25
Speaker 1: into space is that you have nothing to push against
23:28
Speaker 1: once you take that first jump. So if you could
23:30
Speaker 1: just like climb a mountain up into space, it wouldn't
23:33
Speaker 1: actually be that hard. So maybe we should do space
23:35
Speaker 1: ladders instead of these big, old, fancy rockets. Huh, yeah,
23:40
Speaker 1: you're joking, maybe, but there really is a technology there.
23:42
Speaker 1: It's called a space elevator. If you can assemble a
23:45
Speaker 1: cable which connects the surfaces the Earth to like some
23:48
Speaker 1: huge rock out there in orbit, then you can build
23:51
Speaker 1: an elevator that just climbs that cable. It doesn't take
23:53
Speaker 1: nearly as much energy. That would really suck though, if
23:55
Speaker 1: you're on the space elevator and someone pressed all the buttons,
23:58
Speaker 1: because that would take like years. But there's only two buttons.
24:02
Speaker 1: There's Earth and there's space, right, So how long would
24:08
Speaker 1: it take for a star to form, given that it's
24:12
Speaker 1: this really slow, gradual process. We think it might have
24:16
Speaker 1: taken fifty to a hundred million years. And they're not
24:19
Speaker 1: just combating the weakness of gravity. They need to be
24:22
Speaker 1: cold enough. Remember that temperature is like a spedometer for
24:26
Speaker 1: the particles in a gas. Really high temperature gases have
24:29
Speaker 1: particles that are zipping around super fast, and those will
24:32
Speaker 1: resist gravity's tug because they're moving fast enough. So you
24:35
Speaker 1: need these clouds of gas to get cold enough that
24:37
Speaker 1: gravity can win against their velocity and actually pull them together.
24:42
Speaker 1: So it takes fifty to a hundred million years, we
24:45
Speaker 1: think before the first stars start to burn. And so
24:49
Speaker 1: you wait about a hundred million years, right, and you've
24:52
Speaker 1: got a nice star, goat, are we ready to you know,
24:55
Speaker 1: start some life under that stars? There's some kind of
24:59
Speaker 1: problem we're going to run into. Well, that gives us
25:01
Speaker 1: our first ingredient. Right now we have a source of warmth.
25:04
Speaker 1: But if you want a rocky planet to form your
25:06
Speaker 1: life on, while there are no rocks yet, remember the
25:09
Speaker 1: universe so far is just hydrogen and helium, and so
25:13
Speaker 1: all you can do our form denser or less dense
25:16
Speaker 1: blobs of hygen and helium in order to make rocky
25:19
Speaker 1: planets things that have like iron or even carbon or oxygen,
25:23
Speaker 1: so you can make water. Then you need heavier elements
25:26
Speaker 1: in the universe, and that happens at the heart of stars.
25:30
Speaker 1: So in our Solar system for example, that's happening at
25:32
Speaker 1: the heart of our Sun. It's making heavier and heavier elements,
25:35
Speaker 1: the elements that became the Earth. However, we're not made
25:38
Speaker 1: in our son, of course, they were made in a
25:41
Speaker 1: previous sun that burned for billions of years and then
25:44
Speaker 1: spewed those elements out into the universe. But in the
25:48
Speaker 1: first round of stars, there was nothing else, so you
25:51
Speaker 1: can't have a rocky planet around those first stars. So
25:55
Speaker 1: when we're talking about the Big Bang, and the Big
25:57
Speaker 1: Bang happens, it spreads out all of the these elements.
26:01
Speaker 1: But those early elements were more stuff that stars could
26:06
Speaker 1: be formed out of. And only once you had the
26:09
Speaker 1: high energy of the star. Is it because of how
26:13
Speaker 1: hot a star is that they can make those new
26:17
Speaker 1: denser elements. Yeah, the Big Bang was almost all helium
26:21
Speaker 1: and hydrogen. And then to make the heavier elements, what
26:23
Speaker 1: you have to do is take those atoms and push
26:26
Speaker 1: them together, push the nuclei together. And those nuclei don't
26:30
Speaker 1: like to come together, like two protons the core of
26:33
Speaker 1: two hydrogen atoms. They don't like to come together to
26:36
Speaker 1: make helium because they're both positively charged. They repel each other.
26:39
Speaker 1: So to force them together until they stick together and
26:42
Speaker 1: become a heavier nucleus requires you to have a lot
26:45
Speaker 1: of pressure and temperature, so sort of like the universe
26:48
Speaker 1: starts out really hot and dense, and then it cools
26:51
Speaker 1: and spreads out, and then you have to compactify it again.
26:53
Speaker 1: So you can get that really hot furnace at the
26:56
Speaker 1: inside of a star that's capable of generating these heavier elements,
27:00
Speaker 1: and that can only happen inside those stars. So you
27:03
Speaker 1: need stars to form to make the raw materials you
27:07
Speaker 1: need for rocky planets in later generations of stars. Okay,
27:11
Speaker 1: so no stars, no rocks. But once you've got stars,
27:15
Speaker 1: they can start, you know, popping out some rocks, or
27:18
Speaker 1: at least not popping out rocks exactly, but popping out
27:21
Speaker 1: the elements that could then congeal and form rocks. How
27:26
Speaker 1: long do you think it takes from when a star
27:29
Speaker 1: forms and can create these heavier elements to getting let's say,
27:34
Speaker 1: like a small planet. It's really interesting we think that
27:38
Speaker 1: those first generation of stars actually didn't burn for very long,
27:43
Speaker 1: like our son is going to burn. Total lifetime about
27:46
Speaker 1: ten billion years, which is pretty long. But some stars,
27:49
Speaker 1: we think will burn for billions and billions and billions more,
27:52
Speaker 1: maybe even trillions of years. And the thing that determines
27:54
Speaker 1: how long a star lives is its size. A bigger
27:57
Speaker 1: star burns hotter and so it burns through its fuel faster,
28:01
Speaker 1: and a smaller star burns colder, so it doesn't burn
28:04
Speaker 1: its fuel as quickly. So we think that these first
28:07
Speaker 1: stars were really huge, like hundreds of times the mass
28:10
Speaker 1: of the Sun, maybe even more so they only burned
28:13
Speaker 1: a few million years or maybe tens of millions of years,
28:16
Speaker 1: maybe even up to hundreds of millions of years in
28:18
Speaker 1: some cases. And so we think that probably it took
28:20
Speaker 1: a few hundred million years before you had even those
28:24
Speaker 1: elements existing in the universe, you know, to have some
28:27
Speaker 1: like heavier things than helium, but they were at the
28:30
Speaker 1: heart of those stars. So then you need those stars
28:32
Speaker 1: to die and to explode, to go like supernova and
28:36
Speaker 1: blow out some of those materials into the universe to
28:39
Speaker 1: be like compost for the next generation of stars and
28:42
Speaker 1: solar systems that come to form. So probably a few
28:45
Speaker 1: hundred million years before you have some raw materials, but
28:49
Speaker 1: those raw materials you have some heavier elements, but probably
28:52
Speaker 1: not that much carbon and oxygen. All right, So you've
28:55
Speaker 1: got this first generation of stars that were huge and
29:00
Speaker 1: really hot and burn bright, but for shorter and they
29:03
Speaker 1: explode and they give fuel to other stars to form,
29:08
Speaker 1: as well as spreading out elements throughout the universe. What
29:11
Speaker 1: time are we at. We spent to what was it,
29:14
Speaker 1: like a hundred million years for those stars to form.
29:16
Speaker 1: We spent another what was it another hundred million years?
29:19
Speaker 1: A few million, probably a few hundred million years for
29:24
Speaker 1: those suns to create. These elements explode, and then it
29:28
Speaker 1: would take some time for the news stars to form, right,
29:31
Speaker 1: and then take some time for those elements to start
29:35
Speaker 1: to cluster into actual rocks, big space rocks. But we
29:41
Speaker 1: still don't have, like you mentioned, we don't have carbon
29:44
Speaker 1: and oxygen yet. In order to make carbon and oxygen,
29:47
Speaker 1: which are a few steps up the chain using lighter elements,
29:51
Speaker 1: you need stars to burn sort of a long time,
29:53
Speaker 1: so then get like really nice and hot at the
29:56
Speaker 1: center you have a chance to like walk up the
29:58
Speaker 1: ladder of the periodic table. So for that to happen,
30:01
Speaker 1: you need stars to be a little bit smaller so
30:03
Speaker 1: they can burn longer. Because short lived stars burn really
30:06
Speaker 1: hot and fast and just sort of like convert all
30:09
Speaker 1: the hydrogen helium and then explode. And so you need
30:12
Speaker 1: to wait maybe like a billion years after the Big
30:15
Speaker 1: Bang for those smaller, longer burning stars to give up
30:19
Speaker 1: all the carbon and oxygen they've been making at the core.
30:23
Speaker 1: So now we're like a billion years into the universe.
30:25
Speaker 1: We have a bunch of stars, some of them are
30:27
Speaker 1: the second generation of stars, and we have enough of
30:30
Speaker 1: these rocky materials probably to come together and form planets.
30:34
Speaker 1: We have oxygen, we have carbon, but we've already spent
30:37
Speaker 1: a billion years like thing about all of that time
30:41
Speaker 1: that's past. It's incredible, you know that all that time,
30:44
Speaker 1: no Woody observed it, Like it's probably impossible for any
30:48
Speaker 1: form of life as we know it to have formed.
30:50
Speaker 1: But in that first period of the universe, it's essentially
30:52
Speaker 1: like dark from an intellectual point of view, I mean,
30:55
Speaker 1: if you want it done, you can either have it
30:57
Speaker 1: done fast or get you can have it done well.
30:59
Speaker 1: I got always said, so we need an entire billion
31:04
Speaker 1: of years to even have a universe that could possibly
31:10
Speaker 1: possibly foster life, like just to have the ingredients necessary
31:18
Speaker 1: for a life. But that doesn't mean the ingredients are
31:20
Speaker 1: all in the same place at the same time, right
31:24
Speaker 1: there in the universe kind of floating around, but they're
31:28
Speaker 1: not you know, in these neat, little like pots where
31:31
Speaker 1: you're cooking life up. That's right. But you know, if
31:33
Speaker 1: it's out there, then eventually some solar system will form
31:37
Speaker 1: and you'll have enough of these rocky materials in it
31:40
Speaker 1: that you'll get planets forming around the Sun. How long
31:43
Speaker 1: does it take for a solar system to form. We
31:45
Speaker 1: think it takes something like ten million years. It's nothing
31:49
Speaker 1: it needs to see like, you have a cloud of
31:51
Speaker 1: stuff and it might just hang out for a long
31:54
Speaker 1: time for billions of years. Like, not every cloud immediately collapses.
31:57
Speaker 1: You can look at in the night sky right now
31:59
Speaker 1: and see big molecular clouds in our galaxy that have
32:02
Speaker 1: not yet formed stars. You need some sort of like
32:05
Speaker 1: trigger either needs to cool down enough to collapse, or
32:08
Speaker 1: sometimes you need like a nearby supernova to come by
32:11
Speaker 1: and give a shock wave which creates a collapse in
32:14
Speaker 1: the cloud. Is that what we see when we're looking
32:16
Speaker 1: at the Milky Way, these clouds of space stuff? Yeah,
32:20
Speaker 1: our galaxy is still forming new stars in those clouds.
32:23
Speaker 1: Sometimes the two clouds like smash into each other that
32:26
Speaker 1: can create a bunch of stars, or some sort of
32:28
Speaker 1: trigger needs to happen sometimes to collapse these clouds. Otherwise
32:31
Speaker 1: it just takes a long long time for them to cool.
32:34
Speaker 1: And so we think that after the first generation of
32:36
Speaker 1: stars have formed, then the universe is like point one
32:40
Speaker 1: percent heavy metals. And then our Solo system, for example,
32:44
Speaker 1: is about one percent heavy metal. So still the universe
32:48
Speaker 1: is like overwhelmingly like hydrogen and helium, just like one percent.
32:52
Speaker 1: Billions of years have been spent making these heavy metals,
32:55
Speaker 1: and you're still only up to one percent, but that's enough.
32:58
Speaker 1: You can't see it, but I'm through enop double horns
33:01
Speaker 1: for that heavy metal universe exactly. But that's enough to
33:06
Speaker 1: make rocky planets, like our Solar system is on average
33:09
Speaker 1: about one percent not hydrogen and helium, but there's enough
33:13
Speaker 1: to make a whole Earth, right, like enormous blobs of
33:16
Speaker 1: iron and nickel and gold and all the amazing stuff
33:20
Speaker 1: you need to make the complexity of life on Earth.
33:23
Speaker 1: That's enough. So after billion years or so, we think
33:26
Speaker 1: that probably those ingredients are there. And then we get
33:28
Speaker 1: to the really interesting question you were asking earlier, which
33:30
Speaker 1: is like how long do you have to cook it
33:33
Speaker 1: before it turns into life. You have a rocky planet,
33:35
Speaker 1: you have liquid water on the surface, you have carbon
33:39
Speaker 1: and oxygen and nitrogen fluting around. How long before that
33:43
Speaker 1: becomes life? Right? And one of the main enemies of
33:46
Speaker 1: life is chaos and the universe, especially earlier on and
33:53
Speaker 1: a planet when it's new, is typically very chaotic, right,
33:58
Speaker 1: Like that is one of the defining things of like
34:01
Speaker 1: a new planet for me. You just have like boiling
34:05
Speaker 1: seas of various chemicals and you know, unstable sort of geography,
34:12
Speaker 1: and so it's kind of hard to have a planet
34:15
Speaker 1: that's not is at a point of its life where
34:19
Speaker 1: it's calmed down enough that you could even have these
34:24
Speaker 1: delicate chains of proteins come together. But isn't so calm
34:29
Speaker 1: that nothing's happening at all, right, because you need a
34:32
Speaker 1: little bit of chaos, right, You need enough opportunities and
34:36
Speaker 1: need things to bump into each other often enough to
34:38
Speaker 1: the right pieces can like randomly assemble. And of course
34:41
Speaker 1: we don't know how that happened. It's still like a
34:43
Speaker 1: big mystery how life started on Earth. But it is
34:46
Speaker 1: really interesting to look at the timing of it. Right,
34:48
Speaker 1: you were saying life is tenacious, it starts. So what
34:51
Speaker 1: do we know about when life started on Earth? How
34:53
Speaker 1: long did that take, Katie, before our rocky planets started
34:56
Speaker 1: having little critters on it? It was a long time.
34:59
Speaker 1: It's like billion years, right, yeah, another billion years. Like
35:03
Speaker 1: imagine you have this whole rocky planet with all the ingredients,
35:06
Speaker 1: you put it in the oven. You gotta wait a
35:07
Speaker 1: billion years before life starts. It certainly is weird to
35:12
Speaker 1: me to think about it like that because I think
35:15
Speaker 1: about the universe itself and it seems so timeless, And
35:19
Speaker 1: it took the universe a billion years to get to
35:23
Speaker 1: the point where you have you're starting to maybe have
35:26
Speaker 1: conditions where you can have planets and maybe the materials
35:31
Speaker 1: you might need for life. But then it took a
35:33
Speaker 1: whole other billion years on our planet for the first
35:38
Speaker 1: like little life spaghetti is little protein chains to even form.
35:44
Speaker 1: It's I don't know, there's something mind numbing about how
35:48
Speaker 1: vast that is. Well, think about all the things that
35:51
Speaker 1: have to come together in just the right way, and
35:54
Speaker 1: the likelihood of that happening is very small, So you
35:57
Speaker 1: need a lot of opportunities, which means it could take
35:59
Speaker 1: a long time time On the other hand, as you
36:01
Speaker 1: were saying, conditions on Earth weren't really very hospitable in
36:05
Speaker 1: the beginning, you know, the Earth service was like magma,
36:08
Speaker 1: and then there was the huge bombardment of asteroids as
36:10
Speaker 1: the Solar System was still sort of calming down. We
36:13
Speaker 1: still have some signs of those asteroids, write, like big
36:16
Speaker 1: craters and formations on our planet that are like these
36:20
Speaker 1: old battle scars. So from that point of view, life
36:23
Speaker 1: started sort of pretty quickly after things calmed down, Like
36:27
Speaker 1: when you have the right conditions, meaning the basic elements
36:30
Speaker 1: and the right temperature, and you know you're no longer
36:33
Speaker 1: raining fire from the sky and being dissolved in lava.
36:36
Speaker 1: You didn't have to wait that long after that for
36:38
Speaker 1: life to start. And that's just one example, but it's
36:41
Speaker 1: sort of suggestive. It suggests that maybe life isn't that
36:45
Speaker 1: hard to get started. You got the right ingredients in
36:47
Speaker 1: the right place, and maybe just wait a few million
36:50
Speaker 1: years or even a hundred million years, and presto, it
36:53
Speaker 1: will start. Do we know, like when the Earth started
36:57
Speaker 1: to calm down, so to speak, like from when the
36:59
Speaker 1: Earth formed to when the Earth was no longer so
37:04
Speaker 1: jittery and chaotic, that it was just simply too toxic
37:08
Speaker 1: of a personality to host life. Yeah, that was a
37:11
Speaker 1: few hundred million years exactly, So life really did start
37:14
Speaker 1: on Earth pretty quickly after conditions were hospitable. Something I've
37:18
Speaker 1: always wondered about is whether it might have been possible
37:21
Speaker 1: for life to have started on Earth multiple times independently,
37:25
Speaker 1: like you know, a little colony starting on this side
37:28
Speaker 1: of the planet, and another colony maybe using a completely
37:31
Speaker 1: different biochemical technology, starting on the other side of the planet,
37:35
Speaker 1: and you know weather, it could have been like a
37:37
Speaker 1: massive war and our kind of life one and wiped
37:40
Speaker 1: out the other kind of life entirely the way like
37:43
Speaker 1: there are species and geniuses in our own history that
37:45
Speaker 1: we've exterminated. And it could even be something where you
37:48
Speaker 1: have these little pockets of life. They don't even have
37:51
Speaker 1: to have a war, but one of them just kind
37:53
Speaker 1: of fizzles out, whereas the other one manages to make it.
37:58
Speaker 1: Because you know why I'm talking about these protein chains
38:01
Speaker 1: is that is kind of what is thought to have
38:04
Speaker 1: been sort of the first little bits of life where
38:09
Speaker 1: you can you need a chain of protein to form
38:12
Speaker 1: DNA that can build an organism, even a teeny tiny
38:16
Speaker 1: unicellular organism needs DNA structure. Even viruses, things that we
38:22
Speaker 1: hardly call life at all, needs uh sort of DNA
38:26
Speaker 1: structure in order to replicate itself. So that seems to
38:29
Speaker 1: be the key element. And for that to happen, you
38:32
Speaker 1: need these protein chains that are not strong, they're kind
38:36
Speaker 1: of weakly bonded. And so if you have, you know,
38:40
Speaker 1: some rampant molecules zooming around and say a primordial soup,
38:44
Speaker 1: they're gonna knock over this delicate protein chain like bowling
38:49
Speaker 1: pins at a bowling alley, and there goes your first
38:52
Speaker 1: attempt at life. And actually, one of the more compelling
38:56
Speaker 1: theories I've heard of for why life was able to
39:00
Speaker 1: take hold so relatively quickly when you think about just
39:04
Speaker 1: the absurd probabilities, is instead of it being a primordial soup,
39:09
Speaker 1: it's more of a primordial bak leva where you may
39:13
Speaker 1: have these thin sort of sheets of rock and between them,
39:19
Speaker 1: these proteins and molecules can kind of get nestled in
39:23
Speaker 1: there and start to form these chains without being disturbed.
39:29
Speaker 1: So I could imagine a situation where you have life
39:33
Speaker 1: trying to start in different parts of the world and
39:36
Speaker 1: then just getting obliterated by the chaos, and then a
39:39
Speaker 1: few places where hey, it's starting to form in these
39:43
Speaker 1: little nooks and crannies of these rocks where it has
39:46
Speaker 1: a safe refuge and then manages to reach enough strength
39:50
Speaker 1: that it doesn't immediately get obliterated by other molecules. And
39:54
Speaker 1: it's amazing to think about how our little pocketive life
39:58
Speaker 1: won those battles and serve I have. That's crazy chaotic time,
40:01
Speaker 1: and how different life might be on Earth if a
40:04
Speaker 1: different little pocket had survived, if the temperature had been
40:07
Speaker 1: slightly different, or a rocket hit in a slightly different spot,
40:10
Speaker 1: we may have had more than one button. So to summarize,
40:13
Speaker 1: that means that we think it took about a billion
40:16
Speaker 1: or so years for the basic elements to be in place,
40:20
Speaker 1: the carbon, the oxygen, the nitrogen, the rocky planets, the stars,
40:24
Speaker 1: the temperature, and then maybe it took another billion years
40:27
Speaker 1: for things to calm down on that particular planet. That
40:29
Speaker 1: means that life might have started in the universe just
40:32
Speaker 1: a couple of billion years in. That's something like eleven
40:36
Speaker 1: billion years ago. That's billions of years before the Earth
40:40
Speaker 1: even formed, which means that you know, if all this
40:43
Speaker 1: vehiculation is correct. There could be life in the universe
40:46
Speaker 1: that's billions and billions and billions of years older than
40:50
Speaker 1: life on Earth, right, because it took ten billion years
40:53
Speaker 1: for us to come on the scene. So there's something
40:57
Speaker 1: amazing about the idea of like, not only might we
41:00
Speaker 1: not be alone in the universe, but we might never
41:03
Speaker 1: have been alone, like life might have been going about
41:07
Speaker 1: its business and different select little pockets of luck in
41:11
Speaker 1: the universe for all this time. That's right, So let's
41:14
Speaker 1: talk about how life might have formed that's not like
41:17
Speaker 1: life as we know it in the universe, and whether
41:20
Speaker 1: it might have started in the very very very very
41:22
Speaker 1: early universe, if that was possible. But first, let's take
41:26
Speaker 1: another break. All right, we're back, and we're marveling at
41:42
Speaker 1: how long it took life to get started here on
41:44
Speaker 1: Earth compared to the cosmic sweep of history. Wasn't until
41:48
Speaker 1: almost ten billion years into the universe that critters on
41:52
Speaker 1: Earth started to squirm and exchange proteins, whereas we've concluded
41:56
Speaker 1: that it might only take a couple of billion years
41:58
Speaker 1: for the universe to be hospitable to life as we
42:02
Speaker 1: know it. But of course we're talking about life like
42:04
Speaker 1: we know it was one butt and proteins and DNA
42:07
Speaker 1: and RNA and you know, living on a water planet
42:09
Speaker 1: and using our kind of biochemistry. That's just the only
42:12
Speaker 1: example we've ever seen, to be fair, there are Nigerians
42:17
Speaker 1: on our planet that have more than one. But but
42:19
Speaker 1: do you continue, Well, that's a whole other podcast episode.
42:24
Speaker 1: But I think that's probably going to be on your
42:26
Speaker 1: podcast rather than ours. But I'm looking forward to listening.
42:30
Speaker 1: But it does make you wonder, you know, whether life
42:33
Speaker 1: could exist in other forms, and whether those other forms
42:37
Speaker 1: might be conducive to starting even earlier in the universe.
42:41
Speaker 1: So I've heard people speculate about building life out of
42:44
Speaker 1: other biochemical strategies, you know, using ammonia instead of water,
42:48
Speaker 1: using silicon instead of carbon. Do you find those credible, Katie?
42:51
Speaker 1: Do you think that was are just science fiction or
42:53
Speaker 1: do you think it might be the way alien life
42:56
Speaker 1: actually works out there in the universe. I mean, I
42:59
Speaker 1: think it kind of depends first on how we define life, right, Like,
43:04
Speaker 1: that's kind of a tricky question itself. We can't just say,
43:08
Speaker 1: you know, life, because there is currently some debate over
43:12
Speaker 1: what we consider to be life, even on Earth. Right So,
43:15
Speaker 1: like a virus. Like we mentioned earlier, a lot of
43:17
Speaker 1: people do not consider to be life because they are
43:22
Speaker 1: sort of more like these little robots that replicate themselves
43:27
Speaker 1: purely through facilitation of other cells, which is very bad
43:33
Speaker 1: for us when they try to do that. But then
43:36
Speaker 1: you could say, well, okay, but it does reproduce, right,
43:40
Speaker 1: and it does consume other material in order to reproduce.
43:45
Speaker 1: Is that not life? And so I think the likelihood
43:49
Speaker 1: of their being earlier life and life made out of
43:53
Speaker 1: things like silicon and and different types of more unconventional
43:57
Speaker 1: molecules depends on what we think, like if we expand
44:01
Speaker 1: sort of our understanding of what life is, yeah, and
44:04
Speaker 1: going back to our earlier motivation, wondering when there might
44:08
Speaker 1: have been intelligent eyes looking out onto the universe, thinking
44:11
Speaker 1: about galaxies and the nature of reality. If you have
44:15
Speaker 1: a planet that's got like a single cellular life on it,
44:18
Speaker 1: or even just viruses or something, they're not doing any astronomy,
44:21
Speaker 1: they're not doing particle physics, they're not figuring out the
44:24
Speaker 1: secrets of the universe. And so while we paint a
44:26
Speaker 1: picture that the universe might be filled with life even
44:29
Speaker 1: as we know it, that's billions of years old. It's
44:31
Speaker 1: also possible that that life is kind of dumb, right
44:35
Speaker 1: like life on Earth started about a billion years after
44:38
Speaker 1: the Earth began, but intelligent life that's pretty recent, and
44:42
Speaker 1: that might suggest that it's unusual, that it's uncommon. So
44:46
Speaker 1: it might be that there's life everywhere out there and
44:48
Speaker 1: then it's been around for billions of years, but it's
44:51
Speaker 1: very rare for them to be intelligent life actually asking
44:54
Speaker 1: questions about the universe. And that's a little sad, you know,
44:58
Speaker 1: to all these creators out there alling along the surface
45:00
Speaker 1: of their planets but nobody looking up, nobody thinking deeply
45:04
Speaker 1: about the nature of their existence. I guess that's kind
45:06
Speaker 1: of sad, But I think it's also you know, when
45:10
Speaker 1: you start to have some kind of simple thing, right
45:15
Speaker 1: like it all complicated systems start with something really simple.
45:20
Speaker 1: And even though it's true that they don't necessarily ever
45:25
Speaker 1: create something more complex, there's a lot of luck and
45:27
Speaker 1: a lot of good conditions you need. The existence of
45:30
Speaker 1: something simple and dumb often means that eventually you will
45:34
Speaker 1: get something complicated and smart. Maybe, And you know, maybe
45:40
Speaker 1: it's not so sad. Maybe they're very happy because they're busy.
45:43
Speaker 1: You know what they say that the root of all
45:45
Speaker 1: suffering is desire, and so maybe those creators are just
45:48
Speaker 1: happy being those creators and not thinking deeply about the universe,
45:51
Speaker 1: and maybe there's a lesson there about how to live
45:54
Speaker 1: your life. But I like to think about other alternative
45:57
Speaker 1: forms of life, you know, weather for example, you could
46:00
Speaker 1: to have life that forms on the inside of stars,
46:03
Speaker 1: whether you know, even without a rocky planet, if you
46:06
Speaker 1: could have like patterns in the flow of plasmas that
46:10
Speaker 1: are self replicating, right, because it seems like one of
46:14
Speaker 1: the defining characteristics of life isn't necessarily the stuff it's
46:19
Speaker 1: made out of, but the fact that the stuff forms
46:22
Speaker 1: a pattern that can be replicated and have it increase
46:27
Speaker 1: in complexity over time. Right. My understanding of the inside
46:32
Speaker 1: of a star is one, it's very hot. I probably
46:36
Speaker 1: shouldn't be in there. And two it's just a roiling,
46:40
Speaker 1: boiling mess of hot elements being formed and pushed and
46:47
Speaker 1: you know, just incomprehensibly hot and chaotic. So how could
46:52
Speaker 1: life ever form in such an environment. It would have
46:55
Speaker 1: to be life that's pretty different from life that we
46:57
Speaker 1: imagine it. But we do see some sort of structures
47:01
Speaker 1: inside stars, and it's not something we understand very well,
47:04
Speaker 1: like even the patterns within our own sun we do
47:06
Speaker 1: not understand. But there are these massive currents of convection
47:10
Speaker 1: inside the sun, these huge flows of plasma. We know
47:14
Speaker 1: they have to exist because they are when generate, for example,
47:17
Speaker 1: the magnetic field of the Sun, which comes because you
47:20
Speaker 1: have huge flows of these charge currents. Remember magnetic fields
47:24
Speaker 1: come from charge particles in motion, so that definitely happens,
47:28
Speaker 1: and you have these big tubes that are controlled by
47:30
Speaker 1: the magnetic field, and so you might imagine in some
47:33
Speaker 1: sort of science fiction any way that these currents could
47:35
Speaker 1: form and reproduce themselves somehow, but you've got to be
47:39
Speaker 1: pretty creative. On a smaller scale, we have actually seen
47:42
Speaker 1: particles within a plasma sort of self organized, like if
47:46
Speaker 1: you have dust particles inside your plasma, they can sometimes
47:50
Speaker 1: form these like helices that are self organized, and people
47:53
Speaker 1: have imagined that you could build more complex structures from them.
47:56
Speaker 1: But I think you're right that it's fighting a pretty
47:58
Speaker 1: tough battle. But because there's so much energy that is
48:02
Speaker 1: easy to dissociate, to disassemble anything that happens to come together.
48:06
Speaker 1: So it's not something that we've really figured out exactly
48:09
Speaker 1: even how to ask the question. But I think there's
48:11
Speaker 1: an intellectual opening there to imagine how life might exist
48:15
Speaker 1: inside stars or in huge flows between stars, even in
48:20
Speaker 1: the plasma of the interstellar medium, right, because what we
48:23
Speaker 1: talked about with life starting on a chaotic Earth is
48:28
Speaker 1: that we potentially had a little refuge. Right, Like the
48:32
Speaker 1: primordial soup hypothesis might not really work if the soup
48:36
Speaker 1: is too chaotic. But if you have like a primordial pastry,
48:40
Speaker 1: a primordial back lava where you have some kind of
48:43
Speaker 1: like layers of rock where life can squeeze in and
48:48
Speaker 1: find a little bit of an island of stability, it
48:51
Speaker 1: might form. So is there a way for there to
48:53
Speaker 1: be a part of a star inside the star in
48:57
Speaker 1: this plasma, for there to be a little like refuge
49:01
Speaker 1: or island of refuge where there could be some stability
49:05
Speaker 1: inside an unstable environment. It's possible, but it really is
49:09
Speaker 1: a lot of speculation, and so it's just something that
49:11
Speaker 1: we need to continue thinking about. It's really like an
49:14
Speaker 1: intellectual frontier where people are still trying to figure out
49:17
Speaker 1: whether it's possible and whether you could assemble something. But
49:20
Speaker 1: I did really really interesting paper recently thinking about not
49:23
Speaker 1: life inside stars, but life even before stars. Like wondering
49:29
Speaker 1: about whether you could use the whole universe as your
49:32
Speaker 1: energy source. Remember we said you need some sort of
49:35
Speaker 1: energy to keep life warm, right, and so we were
49:38
Speaker 1: thinking about using stars. But the universe actually was quite
49:42
Speaker 1: warm in the very beginning, right, The universe was super
49:45
Speaker 1: duper hot in the first few moments, but then it
49:47
Speaker 1: cooled And now space outside is like three degrees kelvin,
49:51
Speaker 1: but it cooled from very very hot to three degrees kelvin.
49:55
Speaker 1: That means that at some moment it was around you know,
49:59
Speaker 1: three of degrees calvin, which is like you know, room
50:02
Speaker 1: temperature for us. So there was a moment when the
50:05
Speaker 1: universe before stars were even formed, when it was just
50:08
Speaker 1: like a bunch of big cloud of gas that it
50:11
Speaker 1: was about the right temperatures like the room temperature universe.
50:15
Speaker 1: And so that's good in terms of the temperature, I
50:19
Speaker 1: mean that that sounds nice to me, especially because it's
50:22
Speaker 1: cold here right now. But in terms of what the
50:26
Speaker 1: building blocks are, like, how would that work out? Right?
50:29
Speaker 1: What are we working with in terms of these smallest
50:32
Speaker 1: building blocks that could organize into some kind of pattern,
50:36
Speaker 1: It is a real challenge and after. Physicists, however, have
50:39
Speaker 1: already labeled this time in the universe around fifteen million
50:43
Speaker 1: years after the Big Bang. They call it the habitable
50:45
Speaker 1: epic of the universe, just because it's about the right temperature.
50:49
Speaker 1: And I think it's funny to sort of imagine yourself
50:52
Speaker 1: in that universe, because we think of space is so cold,
50:55
Speaker 1: but back then, like space was pretty warm, like the
50:58
Speaker 1: whole universe was around own room temperature. But you're right,
51:01
Speaker 1: how could you form life at that time? It's pretty
51:04
Speaker 1: tough because, as we said, basically everything is just clouds
51:07
Speaker 1: of gas helium and hydrogen, and so in order to
51:10
Speaker 1: get like the heavier elements, you need to make carbon
51:12
Speaker 1: and oxygen. They just worn't around. There is a paper though,
51:15
Speaker 1: that suggests that it might be very unlikely, but it
51:18
Speaker 1: is possible for those things to happen, for those elements
51:22
Speaker 1: to come together, even in those clouds. They did a
51:25
Speaker 1: calculation that suggests it's like a one in ten of
51:28
Speaker 1: the seventeen chance for these things to just sort of
51:31
Speaker 1: like self assemble in these clouds, to get like a
51:34
Speaker 1: nucleus of you know, carbon and oxygen and a little blob.
51:38
Speaker 1: They're happening and so it could actually be like carbon
51:43
Speaker 1: based life just floating in space, in this warm sort
51:49
Speaker 1: of space. Do yeah, in this bath, in this like
51:52
Speaker 1: universe soup. And I can't emphasize enough how speculative this is.
51:57
Speaker 1: This is not like we think has happened. This is like,
52:00
Speaker 1: let's stretch our minds and try to imagine whether it could.
52:04
Speaker 1: Let's release as many constraints as possible, and remember that
52:07
Speaker 1: the universe is vast and even things that are very
52:10
Speaker 1: unlikely could potentially happen. If we're really asking the question
52:13
Speaker 1: about the first time life started, then you got to
52:16
Speaker 1: really push back and allow for crazy stuff to happen. Now,
52:20
Speaker 1: don't back pedal because you said it was this habitable epoch.
52:24
Speaker 1: It sounds really nice. I mean, get like some swim
52:28
Speaker 1: floaties and an inner tube and jump in there and
52:30
Speaker 1: expect only the best to happen. Yeah, but it was
52:33
Speaker 1: a pretty crazy time and there are lots of things
52:35
Speaker 1: going on. And so even if somehow you had like
52:38
Speaker 1: the formation of these heavy elements in the very very
52:40
Speaker 1: early universe and it was living in this soup and
52:44
Speaker 1: somehow life began, it didn't last for very long. Like
52:47
Speaker 1: the universe was this temperature for only a couple million
52:50
Speaker 1: years because it was still cooling, and so the temperature
52:52
Speaker 1: was like dropping right dropping from super crazy hot down
52:56
Speaker 1: to very cold as it is today. So it sort
52:58
Speaker 1: of passed through this window. And after pass through it,
53:02
Speaker 1: you know, then the things would freeze that you couldn't
53:04
Speaker 1: have like liquid water floating out there in the bath
53:07
Speaker 1: of space anymore because it would be too cold. So
53:10
Speaker 1: I think one of the biggest challenges is just like
53:12
Speaker 1: getting it all done within that little window of the
53:15
Speaker 1: habitable epic. I guess that's true. But if space is
53:19
Speaker 1: big enough, right, and you have this sort of space
53:24
Speaker 1: soup in enough area, that does increase the probability, right,
53:28
Speaker 1: because even though you don't have as much time, you
53:31
Speaker 1: have more stuff to cut, Like you know, you have
53:35
Speaker 1: a billion monkeys typing away at Shakespeare. But if you
53:39
Speaker 1: have like a trillion monkeys typing away at Shakespeare, you
53:42
Speaker 1: can get it done in much less time. And that's
53:44
Speaker 1: how you meet your deadlines exactly. So you have to
53:47
Speaker 1: sort of imagine a very vast, almost infinite university even
53:51
Speaker 1: consider this, and then you have to wonder about how
53:54
Speaker 1: long this kind of life could survive. You know, it's
53:56
Speaker 1: a very radiation intensive time in the universe, lots of
54:00
Speaker 1: photons and X rays and all sorts of stuff banging
54:04
Speaker 1: around that would just tear apart in the delicate structures
54:06
Speaker 1: of most kinds of life. But you know, it's a
54:08
Speaker 1: fun intellectual exercise, and we do have life on Earth
54:12
Speaker 1: that it has some resistance to radiation. Obviously there's a
54:17
Speaker 1: limit to it, but things like tarte grades, the little
54:20
Speaker 1: water bears that are so cute, those microscopical guys, do
54:23
Speaker 1: have some resistance to radiation. So I could imagine, although
54:29
Speaker 1: extremely unlikely, maybe you have something that you know, because
54:35
Speaker 1: of these selective pressures of having to survive radiation, it
54:38
Speaker 1: somehow has some protective measures to prevent itself from being
54:43
Speaker 1: just torn apart by little space bullets exactly. And so
54:48
Speaker 1: while I think it's very unlikely this kind of thing
54:50
Speaker 1: might have happened, I do think it's really worthwhile to
54:52
Speaker 1: push the boundaries of our imagination and wonder how life
54:56
Speaker 1: might form, and how it might form differently in different
54:58
Speaker 1: parts of the universe, and how long life might have
55:02
Speaker 1: been around. Remember, we are late comers to this Earth
55:05
Speaker 1: and latecomers to this universe, and so it could be
55:08
Speaker 1: that We are not the first ones to the party,
55:10
Speaker 1: but we have shown up after all the good snacks
55:13
Speaker 1: have been eaten. No, that's the worst thing you've said
55:17
Speaker 1: the whole podcast, which just means we gotta make our
55:21
Speaker 1: own snacks. Hey, there we go. We gotta take our
55:24
Speaker 1: universe stardust and make some rize crispy treats out of it. Exactly. So,
55:29
Speaker 1: thank you very much for listening to us speculate about
55:31
Speaker 1: the very early universe and casting your mind back across
55:35
Speaker 1: this incredible cosmic sweep of history. And thank you Katie
55:39
Speaker 1: for coming along on this journey. Thanks for having me
55:41
Speaker 1: all right, everyone, thanks for listening. Tune in next time.
55:51
Speaker 1: Thanks for listening, and remember that Daniel and Jorge explained.
55:54
Speaker 1: The Universe is a production of my heart Radio. Or
55:57
Speaker 1: more podcast for my heart Radio, visit the i heart
56:00
Speaker 1: Radio app, Apple Podcasts, or wherever you listen to your
56:04
Speaker 1: favorite shows.