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Did this particle cause the Big Bang? · Daniel and Kelly’s Extraordinary Universe

0:08
Speaker 1: Hey, Daniel, do you do anything about economics? Very little? Actually,
0:12
Speaker 1: it's a big mystery to me. Can you think about
0:15
Speaker 1: it like a physicist? You mean like give everything terrible
0:19
Speaker 1: misleading names. Hey you said it. I didn't, But I
0:23
Speaker 1: just mean, like, can you could explain economics using I
0:25
Speaker 1: don't know particles? How would that work? You know? Like
0:28
Speaker 1: what causes the recession? Answer a particle called the recess on?
0:33
Speaker 1: Or what causes inflation and infloton? Yeah? I guess so
0:37
Speaker 1: you could apply that strategy to anything, Like how do
0:39
Speaker 1: cartoons get their ideas by the carton? Actually we get
0:44
Speaker 1: our ideas the same way physicists due using the napton?
1:02
Speaker 1: Hi am or Hey, I'm a cartoonists and the creator
1:04
Speaker 1: of PhD comics. Hi, I'm Daniel. I'm a particle physicist
1:07
Speaker 1: and a professor you see Irvine, And I'm doing experiments
1:10
Speaker 1: to measure the minimum possible nap. Yeah, because I guess
1:14
Speaker 1: your naps are quantum. Also, like, are you napping and
1:17
Speaker 1: not napping at the same time? Because then that way
1:19
Speaker 1: you can get paid for it for your job. Right,
1:22
Speaker 1: I am getting paid while I nap, that's true. But
1:25
Speaker 1: I'm experimenting to see what is the shortest useful amount
1:29
Speaker 1: of nap? Interesting, So you have an alarm clock and
1:31
Speaker 1: you're actually taking data. That's right. I'm exploring the fundamental
1:34
Speaker 1: nature of nap at the smallest scale. I'm wondering, like,
1:37
Speaker 1: you know, is a four minute nap really rejuvenating? Can
1:40
Speaker 1: you take a two minute nap and feel better afterwards?
1:43
Speaker 1: This is the kind of stuff I work on every day.
1:45
Speaker 1: I see you mean shoddy science and if little evidence,
1:48
Speaker 1: they call it subjective evidence. Look, if I need to
1:52
Speaker 1: take a lot of data here to prove my point,
1:55
Speaker 1: I'll do it, you know, for the science. Yeah, take
1:57
Speaker 1: naps all day. Yeah. But welcome to our podcast. Dan
2:00
Speaker 1: and Jorge Explained the Universe, a production of My Heart
2:02
Speaker 1: Radio in which we break down the fundamental nature of
2:05
Speaker 1: the universe, of space and time, of black holes, of
2:09
Speaker 1: neutron stars, of galaxies, of particles, of strings, of everything
2:13
Speaker 1: that came before and everything that will come. We asked
2:16
Speaker 1: the biggest, deepest, hardest, craziest questions about the universe, and
2:20
Speaker 1: we expect answers not from you, but from science. And
2:24
Speaker 1: when we don't have the answers, we tell you about
2:26
Speaker 1: everything that science has thought about these crazy amazing topics
2:30
Speaker 1: and where we might be headed. That's right, because the
2:33
Speaker 1: universe is huge and mysterious and full of questions, and
2:36
Speaker 1: the search for answers doesn't take naps. The human quest
2:40
Speaker 1: to find answers to the biggest questions in the universe
2:42
Speaker 1: is ever going, and there's always someone in the world
2:44
Speaker 1: doing it, so technically it never sleeps, and thank gosh
2:49
Speaker 1: for that. It's sort of incredible to me that we
2:51
Speaker 1: can tackle these biggest of questions. You know, how big
2:55
Speaker 1: is the universe where did it come from? That we
2:57
Speaker 1: actually have like a mechanism as these time little cree
3:00
Speaker 1: cheers on these tiny little rock in one corner of
3:02
Speaker 1: the universe to reach our minds out and maybe solve
3:05
Speaker 1: these cosmic puzzles. Yeah, it's amazing. And we've only been
3:08
Speaker 1: doing it for like a few hundred years, I mean
3:10
Speaker 1: in earnest right, and so we've been able to do
3:13
Speaker 1: a lot just from this little tiny floating rock in
3:15
Speaker 1: one corner of the universe with the coded basically a
3:18
Speaker 1: lot of where the universe came from. Yeah, and a
3:20
Speaker 1: lot of those few hundred years were spent napping, and
3:23
Speaker 1: so you know, it's even more impressive how much we've learned, right,
3:26
Speaker 1: most of us done in Europe, I guess right. So
3:28
Speaker 1: it's a siesta kind of afternoon tea. Though sometimes you
3:32
Speaker 1: get great ideas during naps, often to wake up from
3:34
Speaker 1: a nap and have like three good ideas for what
3:37
Speaker 1: to do next, And you say often do you mean like,
3:40
Speaker 1: sometimes you get terrible ideas too, and it's a wash
3:44
Speaker 1: at the end. What's what's your head rate for nap? Brilliant?
3:48
Speaker 1: All the ideas I have are terrible. But that's the process, right.
3:52
Speaker 1: The first idea is always terrible, but sometimes it inspires
3:54
Speaker 1: a better idea, maybe in you, maybe in the other
3:57
Speaker 1: person you tell this idea to. Honestly, jokes aside, that's
4:01
Speaker 1: one of the joys of collaborating with all the young
4:03
Speaker 1: people in my group is that they come in with
4:05
Speaker 1: a terrible idea and it inspires another better idea in
4:08
Speaker 1: somebody else. That's the whole process of science. I thought
4:12
Speaker 1: you were going to say that the joy was that
4:13
Speaker 1: you can come up with terrible ideas and then they'll
4:15
Speaker 1: do it, and then they'll tell you when it doesn't work,
4:17
Speaker 1: so you can keep napping. There's that also, But it
4:20
Speaker 1: is amazing how these naps, and these terrible ideas have
4:23
Speaker 1: somehow coalesced into a pretty nice cohesive view of the
4:28
Speaker 1: whole universe, of how it works, of its ancient, ancient history.
4:32
Speaker 1: It's amazing what we've learned without really exploring, just by
4:35
Speaker 1: gathering information from the light and the particles that happened
4:38
Speaker 1: to fall on Earth. Yeah, and so we have a
4:40
Speaker 1: pretty good picture of the universe, at least the observable universe,
4:43
Speaker 1: and all the amazing things that happened in it, and
4:45
Speaker 1: even its origin. We have a pretty good picture of
4:48
Speaker 1: what happened when the universe was born, and how it
4:51
Speaker 1: happened and how fast it happened. But there are still
4:54
Speaker 1: big questions about it, that's right. One of those questions
4:57
Speaker 1: is exactly how you define when it was born. And
5:00
Speaker 1: we keep pushing further and further back in the cosmic history,
5:03
Speaker 1: thinking back to how galaxies were formed, and before that,
5:06
Speaker 1: how stars were formed, and before that, how the gas
5:08
Speaker 1: that made those stars were formed, and before that, how
5:11
Speaker 1: the particles that went into the gas were formed, and
5:13
Speaker 1: even further and further back. But the further back we pushed,
5:16
Speaker 1: the harder it is to understand what the causes of
5:19
Speaker 1: those causes are, yeah, because looking for the causes of
5:22
Speaker 1: the causes is what science is all about. And in particular,
5:26
Speaker 1: we're asking this question about the beginning of the universe,
5:29
Speaker 1: the Big Bang, or there's sort of a more technical
5:32
Speaker 1: term for it, right, that's right. These days, an important
5:34
Speaker 1: part of what we used to call the Big Bang
5:36
Speaker 1: is this period of incredible expansion of the universe, which
5:40
Speaker 1: we now call inflation, borrowing a term from economics. That
5:44
Speaker 1: things get more expensive in the universe, also very rapidly
5:47
Speaker 1: in those first moments technically, right, I mean, things and
5:50
Speaker 1: things went up in value a lot. You used to
5:52
Speaker 1: be able to buy a whole solar system with one star.
5:55
Speaker 1: Now you need like a binary star system. Eventually you
5:57
Speaker 1: need like a trinary star system. Eventually every star sist
6:00
Speaker 1: is going to have like five or six stars in it.
6:02
Speaker 1: Right yet, I mean, technically the universe used to fit
6:04
Speaker 1: in your wallet before. Now you need a whole banking system,
6:07
Speaker 1: if not more. That's right. And we keep getting these
6:09
Speaker 1: descriptions of earlier and earlier times of the universe. But
6:12
Speaker 1: as you say, we don't just want to find the
6:14
Speaker 1: cause of this particular event. We want to find the
6:16
Speaker 1: cause of that cause, and if that cause, and of
6:18
Speaker 1: that cause, and hanging over this whole question, of course,
6:22
Speaker 1: is the deeper philosophical question of was there a first
6:25
Speaker 1: cause or do the causes just go back forever into
6:28
Speaker 1: the depths of time causing each other. Yeah, and so
6:31
Speaker 1: today we'll get to the root of the whole universe
6:33
Speaker 1: here by asking a pretty big question about what caused
6:36
Speaker 1: the Big Bang and inflation. So today on the program,
6:39
Speaker 1: we'll be asking the question, what is an Inflaton? Now, Daniel,
6:49
Speaker 1: is that Inflaton or Inflaton? It's French, so it's inflate inflict.
6:54
Speaker 1: Feel like you've in sold so many French speakers in
6:57
Speaker 1: both Canada and France when you for your French accent,
7:02
Speaker 1: My attempt to speak French is insulting to the very
7:04
Speaker 1: French language. Is that what you're saying? I am not French.
7:07
Speaker 1: I'm just happy you're not trying to do a Spanish accent.
7:09
Speaker 1: Oh yeah, exactly. Well, you know, in my brief attempt
7:12
Speaker 1: to speak French, people who were actual French speakers told
7:15
Speaker 1: me that my French accent was terrible. So then I
7:18
Speaker 1: tried an exaggerated French accent like a pepper lepew sort
7:21
Speaker 1: of insulting French accent, and then they were like, yes,
7:23
Speaker 1: that's much better. No, they said better, They didn't say
7:26
Speaker 1: it was good exactly. You should always take their word.
7:30
Speaker 1: It's always an iterative process. But in this case, physicists
7:33
Speaker 1: called this an infloton. Usually particles we invent we have
7:36
Speaker 1: the suffix of on, like photon boson for me on.
7:39
Speaker 1: So this would be an inflocton. I guess that gives
7:41
Speaker 1: it sort of an element of individual nous or like succinctness,
7:45
Speaker 1: you know, or like you know, wholeness. There's a unitarity
7:48
Speaker 1: to it, yeah, I mean, it's not the electron ish
7:50
Speaker 1: or the proton ing right. It's the proton right and
7:54
Speaker 1: the electron Yeah, yeah, exactly. And so this is a
7:57
Speaker 1: pretty interesting question. What is an inflocton? And did it
8:00
Speaker 1: cause the Big Bang through inflation? And so, as usually,
8:04
Speaker 1: we were wondering how many people out there had heard
8:06
Speaker 1: of this interesting and theoretical and mysterious particle. So Daniel
8:10
Speaker 1: went out there and as people on the internet, what
8:13
Speaker 1: is an imfloton? And you don't have to be on
8:15
Speaker 1: the internet to participate, You just have to be a
8:17
Speaker 1: listener who wants to answer silly physics questions without the
8:21
Speaker 1: opportunity to do any research. So reach out to me
8:24
Speaker 1: if you'd like to participate to questions at Daniel and
8:27
Speaker 1: Jorge dot com. I'll email you the questions and you
8:30
Speaker 1: can just zip back the audio to us. Please participate.
8:33
Speaker 1: Everybody's welcome. So think about it for a second. Do
8:36
Speaker 1: you know what an infloton is or how would you
8:39
Speaker 1: try to describe it? Here's what people had to say.
8:42
Speaker 1: The word inflaton makes me think of inflation, So I
8:45
Speaker 1: think an inflaton is theoretical or mathematical placeholder to explain
8:52
Speaker 1: dark energy. So I have no idea what an inflaton is,
8:57
Speaker 1: but it does make me think of me maybe particles
9:01
Speaker 1: that are in an electro magnetic um shield, like what's
9:07
Speaker 1: happening around Earth. I think inflation is happened at the
9:11
Speaker 1: beginning of the Big Bang, where the space and all
9:15
Speaker 1: the matter inflated into what we see. Now. You have
9:20
Speaker 1: no idea. I've never heard about it, and I literally
9:24
Speaker 1: could have just thought like maybe a new particle discovered
9:27
Speaker 1: or based on the name, something to do with any
9:30
Speaker 1: kind of inflations in the universe, maybe other than being
9:35
Speaker 1: some type of particle. I have no idea. An inflaton
9:39
Speaker 1: is a theoretical particle that is related to the mechanisms
9:44
Speaker 1: of the inflation of the universe. Maybe it helps explain
9:48
Speaker 1: why or how that happened. If I had to guess,
9:51
Speaker 1: I'd say an inflaton has to do with inflation the
9:55
Speaker 1: inflationary period of the early universe. So maybe a particle
9:58
Speaker 1: that only existed during inflat So maybe this particle is
10:01
Speaker 1: actually well named. What do you mean because nobody knows
10:04
Speaker 1: what it is, because everybody has the idea that it's
10:07
Speaker 1: connected somehow to cosmic inflation. Yeah. Yeah, it's a pretty
10:11
Speaker 1: good naming this time. Well, I don't know. I mean,
10:13
Speaker 1: let's find out what it does and how it's related
10:15
Speaker 1: to inflation first before passing a judgment, you're almost going
10:18
Speaker 1: to say something positive about a particle physics name, and
10:20
Speaker 1: then you pull back at the last second. Check back
10:24
Speaker 1: with me in an hour here, all right, we'll do
10:27
Speaker 1: I'll let you know. But yeah, I guess most people
10:29
Speaker 1: connected it to inflation, which is good, although some people
10:32
Speaker 1: try to connect it to dark energy maybe and some
10:35
Speaker 1: people just had no idea. Yeah, And the connection to
10:37
Speaker 1: dark energy is not a terrible one, because inflation is
10:40
Speaker 1: a big expansion of the universe, and dark energy is
10:43
Speaker 1: just the observation that that's expansion. This accelerating expansion is
10:47
Speaker 1: still continuing to present day. So as we might dig
10:50
Speaker 1: into later, there might be connections between inflation and dark energy.
10:54
Speaker 1: All right, well, let's take the first step here and
10:56
Speaker 1: let's talk about what is inflation. So we talked about
11:00
Speaker 1: how it's part of the Big Bang, but it's not
11:02
Speaker 1: sort of the whole Big Bang, right, that's right, And
11:04
Speaker 1: this sort of an evolution of what we mean by
11:06
Speaker 1: the Big Bang. I think the initial idea for a
11:09
Speaker 1: big bang is sort of like a tiny little dot
11:12
Speaker 1: of matter sitting in deeply empty space and then exploding
11:16
Speaker 1: that you had infinitely dense matter of singularity like you
11:19
Speaker 1: might imagine exists in the heart of a black hole,
11:21
Speaker 1: which then exploded all the way through space, and then
11:24
Speaker 1: that matter is moving through space. That's sort of like
11:27
Speaker 1: the early ideas of a big bang, right right, Like
11:29
Speaker 1: we thought maybe it was like a grenade or something
11:31
Speaker 1: that was just sitting there in space exactly these days
11:34
Speaker 1: we have a different concept of how the Big Bang
11:36
Speaker 1: might have happened. The crucial difference is that it's not
11:39
Speaker 1: an explosion of stuff through space, but an expansion of
11:42
Speaker 1: space itself. The space itself gets stretched, and so you
11:46
Speaker 1: don't need like a tiny dot of matter inside big
11:49
Speaker 1: empty space. You can have space itself be already infinite
11:53
Speaker 1: and already filled with matter. But that matter was hot
11:56
Speaker 1: and dense, and then it got stretched out, it got
12:00
Speaker 1: banded into a cooler, more separated, more dilute universe. So
12:04
Speaker 1: that's the idea of inflation, that you took space itself
12:07
Speaker 1: and stretched it and expanded it. So we've reimagined the
12:10
Speaker 1: Big Bang is having this period we call inflation where
12:13
Speaker 1: the universe goes from very very dense to very very
12:15
Speaker 1: not dense. It's like the whole room where stuff was
12:19
Speaker 1: actually is what also got bigger. Right, It's not just
12:22
Speaker 1: like the stuff got bigger, it's like the room got
12:24
Speaker 1: bigger too, exactly. And another important difference is that this
12:27
Speaker 1: doesn't need a singularity like one problem with the idea
12:31
Speaker 1: of a big bang is this concept of a singularity.
12:34
Speaker 1: When the universe was like infinitely dense, infinities don't really
12:38
Speaker 1: appear in nature as far as we can tell. I mean,
12:41
Speaker 1: the universe might be spatially infinite, it might be infinite
12:45
Speaker 1: all way back in time, but nobody's ever observed any infinities.
12:48
Speaker 1: This is a concern also for singularities at the heart
12:51
Speaker 1: of black holes, which we think are inconsistent with quantum mechanics.
12:54
Speaker 1: So this singularity the beginning of the universe. For the
12:57
Speaker 1: early Big Bang models, it's always sort of a problem,
12:59
Speaker 1: and this replaces it. This says, well, you don't have
13:01
Speaker 1: a singularity. You just start out with something really, really
13:04
Speaker 1: hot and dense, and then you get this massive expansion
13:07
Speaker 1: of it. And this expansion is really dramatic. We're talking
13:11
Speaker 1: about an expansion of the factor of ten to the thirty.
13:14
Speaker 1: That's ten with thirty zeros past it. Right, It's like,
13:17
Speaker 1: I don't even know what the prefix for that is.
13:20
Speaker 1: I think it's an influent number, right, it's an influllion.
13:23
Speaker 1: I think it's a gazillion number maybe, but the gillion anyway,
13:26
Speaker 1: it's a huge number. It's hard to even really imagine.
13:29
Speaker 1: And the whole thing happened intend to the minus thirty
13:32
Speaker 1: two seconds. So it's this incredible expansion. You know, something
13:36
Speaker 1: the size of a centimeter now becomes trillions and trillions
13:39
Speaker 1: of kilometers long, all intended to minus thirty two seconds,
13:43
Speaker 1: and that's just to paint a picture that's like zero
13:45
Speaker 1: point and then thirty two zeros and then a one
13:49
Speaker 1: seconds exactly. So it's a really short amount of time, obviously,
13:53
Speaker 1: especially in the context of the whole history of the universe, right,
13:56
Speaker 1: which is fourteen billion years, and it's maybe the most
13:59
Speaker 1: dramatic thing that's ever happened. It started with a bang.
14:02
Speaker 1: But is it a coincidence that, you know, the during
14:05
Speaker 1: inflation the universe expanded by tend to the thirty intend
14:08
Speaker 1: to the negative thirty two, like that seems like pretty symmetric.
14:11
Speaker 1: Somehow they do seem sort of related, But there's a
14:13
Speaker 1: lot of uncertainty in those numbers. Different models of inflation
14:16
Speaker 1: give you different numbers. Some models of inflation have more expansion,
14:20
Speaker 1: tend to the fifty even up to tend to the seventy,
14:22
Speaker 1: and some models of inflation to think this might have
14:24
Speaker 1: happened faster down to tend to the minus thirty six
14:26
Speaker 1: even for example. So there's a lot of uncertainty. So
14:29
Speaker 1: you're saying your theories are like plus or minus to
14:32
Speaker 1: thet you know, just a small error. Yeah, and later
14:35
Speaker 1: on we'll talk about you know, mistakes. We've made that
14:37
Speaker 1: a factor tend to the one hundred. So you know,
14:40
Speaker 1: when you're taking on big questions, you sometimes make big mistakes.
14:43
Speaker 1: Just like we said, sometimes your first idea is wrong.
14:46
Speaker 1: In fact, nine of your ideas are probably wrong. Sometimes
14:49
Speaker 1: you have a bad nap. I tend to overslept by
14:53
Speaker 1: tending the thirty hours, and now the universe is over.
14:58
Speaker 1: As long as I get overpaid by tend of the
15:00
Speaker 1: thirty that's no problem for me. And so this is
15:03
Speaker 1: kind of a crazy theory, right, I remember talking about
15:05
Speaker 1: this for our books, sent for some of the stuff
15:08
Speaker 1: that we do together. And it's sort of a crazy idea,
15:10
Speaker 1: right that the the fact that the universe expanded so
15:13
Speaker 1: fast and so much in such a little amount of time.
15:15
Speaker 1: But that's sort of the only thing that makes sense,
15:18
Speaker 1: right from what we see and from our theories about
15:20
Speaker 1: the universe. Yeah, this idea is not just something invented
15:23
Speaker 1: by theories too have a bad nap. It's something which
15:26
Speaker 1: solves a lot of problems with the old Big Bang theory.
15:29
Speaker 1: The old Big Bang theory and this explosion of a
15:31
Speaker 1: big universe grenade didn't explain what we actually saw out
15:35
Speaker 1: there in the universe. It was hard to sort of
15:38
Speaker 1: make that fit. And one of the biggest problems with
15:40
Speaker 1: that theory is that it didn't explain basically how smooth
15:44
Speaker 1: the universe is. Like we are getting photons right now
15:47
Speaker 1: from parts of the universe that are very very far apart.
15:51
Speaker 1: Like if you look to the left, you're getting photons
15:54
Speaker 1: from the very beginning of the universe, and those photons
15:57
Speaker 1: are coming from very very far away. And then you
15:59
Speaker 1: look to the right and you're getting photons from a
16:01
Speaker 1: totally different part of the universe that have been traveling
16:04
Speaker 1: for the whole history of the universe. Now in theory,
16:07
Speaker 1: those photons are meeting for the very first time. So
16:10
Speaker 1: the patches of the universe that they came from have
16:12
Speaker 1: never been in contact before, right, Their photons have been
16:15
Speaker 1: traveling the whole history of the universe, just meeting today
16:18
Speaker 1: for the very first time. They've had no chance to
16:20
Speaker 1: coordinate or talk to each other. But what we see
16:23
Speaker 1: out there in the universe is that everything seems to
16:26
Speaker 1: be about the same temperature, like those photons have about
16:29
Speaker 1: the same energy, And that's the kind of thing you
16:31
Speaker 1: expect to happen when stuff is in contact with each other,
16:35
Speaker 1: like when you first pour cream into your coffee, you
16:38
Speaker 1: have hot spots and cold spots. But then you wait
16:40
Speaker 1: a little while and this stuff talks to each other
16:42
Speaker 1: and exchanges photons, and everything becomes smooth and evenly temperatured.
16:46
Speaker 1: The universe seems sort of smooth and evenly temperatured, even
16:50
Speaker 1: though parts of it never have spoken before. Right. Right,
16:53
Speaker 1: it's like you look to the right and you look
16:54
Speaker 1: to the lout and you don't see any like hot
16:57
Speaker 1: spots or could spots in the universe. Right, It's like
17:00
Speaker 1: the universe had come from a grenade. You might expect,
17:02
Speaker 1: like when one direction it would look hotter and the
17:04
Speaker 1: other direction would look colder. That's right, And we do
17:06
Speaker 1: see some very small variations. We'll talk about that in
17:09
Speaker 1: a minute. In the cosmic microwave background radiation. That's this
17:12
Speaker 1: very very old light that we're seeing from the very
17:15
Speaker 1: early universe. But it's remarkably smooth. It's much smoother than
17:19
Speaker 1: it really should be. And so inflation solves this problem
17:23
Speaker 1: because inflation says, oh, no big deal. These guys were
17:27
Speaker 1: in contact fourteen billion years ago before I stretched the
17:30
Speaker 1: whole universe. These things were close enough to be exchanging photons,
17:34
Speaker 1: to be talking to each other, to be sharing their energy,
17:37
Speaker 1: to smooth out any big lumps, any big variations. And
17:41
Speaker 1: that's why the universe looks so smooth, because it had
17:44
Speaker 1: a chance to sort of mix and become even temperatured
17:47
Speaker 1: before it got stretched out to be so massive. I guess,
17:50
Speaker 1: are you assuming that before the Big Bang, before this
17:53
Speaker 1: inflation period, things were stable, like things were hanging out
17:57
Speaker 1: in this superdense state for a while, or are you
18:00
Speaker 1: saying just from being so crunched together so much that
18:03
Speaker 1: they would have had a chance to even out. Yeah,
18:05
Speaker 1: I wouldn't say a while, because we're talking like ten
18:08
Speaker 1: to the minus thirty seconds, but long enough to thermalize,
18:12
Speaker 1: long enough to come into equilibrium. We think that whatever
18:15
Speaker 1: happened before inflation was there for long enough for things
18:18
Speaker 1: to smooth out mostly smooth out to the level where
18:22
Speaker 1: all you expect are random quantum fluctuations. Like nothing in
18:26
Speaker 1: the universe is perfectly smooth because of quantum mechanics, you're
18:29
Speaker 1: always getting virtual particles bubbling up and and creating tiny
18:33
Speaker 1: little pockets of extra density. But that's the idea that
18:35
Speaker 1: the universe had a chance to even out and smooth
18:38
Speaker 1: out down to the level of quantum fluctuations. And so
18:41
Speaker 1: if that's true, then you should look out into the
18:43
Speaker 1: universe and see it be mostly smooth with a few
18:46
Speaker 1: little wrinkles. But the Big Bang theory would suggest something
18:50
Speaker 1: much more dramatic, right, would suggest that things have never
18:53
Speaker 1: been in contact before, and so there's no way that
18:56
Speaker 1: these things could be so smooth. Right, So I guess
18:59
Speaker 1: the only way to plane the sort of even temperature
19:01
Speaker 1: of the universe is if it's space itself with some
19:04
Speaker 1: what's crunched together before, and we don't expect it to
19:07
Speaker 1: be perfectly even, right, we have these quantum fluctuations. Any
19:11
Speaker 1: field in space is never gonna be like totally even
19:15
Speaker 1: or smooth. There's always gonna be virtual particles bubbling up
19:17
Speaker 1: in small quantum randomness happening. And so inflation also explains
19:22
Speaker 1: why we have structure in the universe today. Like, the
19:24
Speaker 1: universe is not totally smooth. It's not like we have
19:27
Speaker 1: one hydrogen atom per light year or something like that.
19:30
Speaker 1: We haven't spread out matter through the universe like peanut
19:33
Speaker 1: butter on a piece of bread. It is a little
19:35
Speaker 1: bit lumpy, right. You have planets and stars and galaxies,
19:38
Speaker 1: and those lumps come from these little initial quantum fluctuations
19:43
Speaker 1: in the pre inflationary matter whatever that was before inflation,
19:47
Speaker 1: there little quantum fluctuations. It's mostly smoothed out. You get
19:50
Speaker 1: little quantum fluctuations, and then those get blown up by
19:54
Speaker 1: inflation to be the seeds of the structure that we
19:57
Speaker 1: see today. Right, Well, I guess you expect gravity to
20:00
Speaker 1: give a smooth universe structure. But I think what you
20:03
Speaker 1: said before is that gravity isn't enough to give us
20:05
Speaker 1: the structure that we see today, right, like the galaxies
20:08
Speaker 1: and the galaxy clusters, like, you need something more to
20:11
Speaker 1: explain the structure. And one good source for that structure
20:14
Speaker 1: to come from is from the quantum fluctuations, which would
20:17
Speaker 1: only happen if space itself also crunched together. Yes, so
20:20
Speaker 1: these initial quantum fluctuations get blown up by inflation to
20:24
Speaker 1: be on a larger scale, and then gravity takes over,
20:26
Speaker 1: as you say, and you know, you have a universe
20:28
Speaker 1: filled with matter with some variations in it, and then
20:31
Speaker 1: gravity takes over and clumps that stuff together and you
20:34
Speaker 1: get big blobs which turn into galaxies and stars and
20:37
Speaker 1: planets and all that kind of stuff. But gravity can
20:39
Speaker 1: only do that if it has something to start with,
20:41
Speaker 1: if it was perfectly smooth to begin with. Gravity can't
20:44
Speaker 1: get a foothold because everything is being pulled in all
20:47
Speaker 1: directions but at the same amount, and so there's sort
20:50
Speaker 1: of nothing to get it going, all right, So then
20:52
Speaker 1: inflation makes sense because it sort of explains the way
20:55
Speaker 1: things are and what we see out there in the universe,
20:58
Speaker 1: and it also makes some predictions out some of the
21:00
Speaker 1: background radiation that we see out there, and so let's
21:02
Speaker 1: get into that. But first let's take a quick break,
21:17
Speaker 1: all right, Daniel, we're talking about inflation and why Hamburger
21:22
Speaker 1: costs more these days because of the Big Bang, right,
21:25
Speaker 1: because because it was made in the forge of quantum fluctuations.
21:30
Speaker 1: It's because of the Hamburger on particles. Yeah, Now we're
21:32
Speaker 1: talking about the beginning of the universe and the period
21:35
Speaker 1: during the Big Bang in which things blew up really
21:38
Speaker 1: fast and lot, and that's called inflation, and we're talking
21:41
Speaker 1: about what might be costing inflation. But first we talked
21:44
Speaker 1: about sort of why inflation makes sense, because it is
21:46
Speaker 1: a crazy idea and we know it sort of explains
21:48
Speaker 1: a lot of things, and it also makes some predictions
21:50
Speaker 1: which we can verify. Right, you have to cast your
21:52
Speaker 1: mind back about years before we had really detailed measurements
21:57
Speaker 1: of the cosmic microwave background radiation. Remember, these are photons,
22:01
Speaker 1: which are the sort of the oldest light in the universe.
22:03
Speaker 1: The universe was a hot and dense plasma like the
22:06
Speaker 1: center of the Sun. And when a photon is emitted
22:08
Speaker 1: in the center of the Sun, it doesn't just like
22:10
Speaker 1: fly out of the Sun. It gets reabsorbed because the
22:12
Speaker 1: Sun is opaque. So the whole universe was like that.
22:15
Speaker 1: It was thick and opaque, and photons that were made
22:18
Speaker 1: were just reabsorbed. Then things cooled down enough so that
22:21
Speaker 1: suddenly the universe became transparent and photons made at that
22:25
Speaker 1: moment are still flying around through the universe. So that's
22:28
Speaker 1: the oldest light that we can see, and that gives
22:31
Speaker 1: us a sense for like what the temperature was at
22:34
Speaker 1: any place in the universe, and there are little hot
22:36
Speaker 1: spots and there were little cold spots. So this light
22:39
Speaker 1: was first discovered in the sixties. It was really evidence
22:41
Speaker 1: that the universe used to be hot and dense, and
22:45
Speaker 1: then later on people discovered, oh, there's some hot spots
22:48
Speaker 1: and some cold spots in it. But before all those
22:51
Speaker 1: hot spots were measured to great detail, inflationary models, the
22:55
Speaker 1: folks working on this kind of cosmology predicted that there
22:58
Speaker 1: would be those wiggles. They say, if you measure this really,
23:01
Speaker 1: really carefully, you'll find that it's not all the same temperature,
23:05
Speaker 1: it's not all the same energy photons. You should see wiggles,
23:08
Speaker 1: and you should see wiggles that look just like this.
23:10
Speaker 1: And then people develop these satellites and these telescopes to
23:13
Speaker 1: look at that light with great precision, and they saw
23:16
Speaker 1: exactly those wiggles that inflation predicted, right, And it didn't
23:20
Speaker 1: sort of like predict what the wiggles would exactly look like.
23:23
Speaker 1: What they predicted like things about it, right, like they
23:25
Speaker 1: should be like this curvy and this bumpy and this
23:28
Speaker 1: you know at this you know general frequency. Right, It's
23:31
Speaker 1: like it predicted what they should the general properties of
23:34
Speaker 1: these wiggles. Yeah, they didn't predict like where one wiggle
23:37
Speaker 1: would be, like where you would have a hot spot
23:38
Speaker 1: and where you would have a cold spot. That's random.
23:41
Speaker 1: But what they can do is predict how big should
23:43
Speaker 1: those hot spots be, how big should those cold spots
23:46
Speaker 1: be like should an entire half of the sky be
23:49
Speaker 1: a hot spot? Or should the hot spots be like
23:51
Speaker 1: one degree in the sky or point one degree in
23:53
Speaker 1: the sky. And very specifically, what inflation predicts is that
23:57
Speaker 1: you have quantum fluctuations all throughout inflation. It's not like
24:01
Speaker 1: you just had quantum fluctuations before inflation. As the universe
24:05
Speaker 1: is inflating, you keep getting quantum fluctuations. And so what
24:09
Speaker 1: that means is that you should get wiggles of all sizes.
24:12
Speaker 1: You should get wiggles of one degree in wiggles, a
24:14
Speaker 1: point one degree in point oh one degrees and all
24:16
Speaker 1: those things. So if you look for these, you should
24:19
Speaker 1: expect to see all different kinds of wiggles, like basically
24:21
Speaker 1: at all different scales. And that's exactly what they see,
24:25
Speaker 1: and so that's really exciting. It really suggests that you're
24:27
Speaker 1: like you're seeing quantum fluctuations as inflation is happening. It's
24:32
Speaker 1: almost like a fractal kind of like you should see
24:34
Speaker 1: a certain level of fractalness in the wiggles of the universe. Yeah,
24:37
Speaker 1: some people think of it like we're watching time click
24:39
Speaker 1: forward as inflation is happening. It's leaving this imprint on
24:43
Speaker 1: the universe as it happens. So that was pretty exciting.
24:46
Speaker 1: That's pretty convincing that inflation really is a good description
24:49
Speaker 1: of what happened, right, right, And so again, inflation is
24:52
Speaker 1: this idea that the space itself expanded by this crazy
24:55
Speaker 1: amount to everything was crushed together, and then at one
24:59
Speaker 1: point in time time it expanded by a factor of
25:01
Speaker 1: tent to the thirty in ten to the minus thirty
25:04
Speaker 1: two seconds. And that's pretty wild, right, Like that's a
25:07
Speaker 1: huge amount of expansion and space and things moving and exploding.
25:11
Speaker 1: But there has to I guess the big question is
25:13
Speaker 1: like what costed? Like why would the universe suddenly do that? Yeah,
25:16
Speaker 1: what we've done so far is just describe what we
25:19
Speaker 1: think happened, Like in order to create the universe that
25:22
Speaker 1: we're looking at, what sequence of events do you need
25:24
Speaker 1: to orchestrate? Now we need to take the next step
25:26
Speaker 1: and say, all right, that describes what we think happened.
25:29
Speaker 1: But why did it happen? What caused that? Right? And
25:33
Speaker 1: this is this eternal chicken an egg? Who ordered that? Yeah?
25:36
Speaker 1: Who laid this egg? Right? And when we figure out who, say,
25:39
Speaker 1: we're like, all right, well, where did that chicken come from.
25:41
Speaker 1: And you know, it might be an eternal question that
25:43
Speaker 1: we keep going further and further back, but it's a
25:45
Speaker 1: fun question. And this is the process, right. We need
25:48
Speaker 1: to nail down what we think happened, and then we
25:50
Speaker 1: can look for explanations for what might have caused that
25:53
Speaker 1: and nailed down with the parameters of that are, and
25:55
Speaker 1: then we can ask, okay, well, you know, does that
25:57
Speaker 1: make sense? And what could have caused that? And what
25:59
Speaker 1: can editions do you need for that to work? And
26:02
Speaker 1: this is the process of science. This is how funny
26:04
Speaker 1: little monkeys on a tiny little rock in a corner
26:06
Speaker 1: of the universe can peer out at photons landing on
26:09
Speaker 1: the surface of their planet and learn things about the
26:12
Speaker 1: very origin of the universe. Yeah, just being curious and
26:15
Speaker 1: asking questions. Ask a question is sort of like one
26:18
Speaker 1: of those annoying kids sometimes and asking the government for
26:22
Speaker 1: billions of dollars in fancy eyeballs to use to look
26:25
Speaker 1: at this crazy light right, right and to think about
26:27
Speaker 1: it doing your naps, that's right. And so to summarize
26:29
Speaker 1: what we need the universe to have done is to
26:32
Speaker 1: have this crazy period of expansion, right, really really rapid
26:35
Speaker 1: expansion and then stop. Right, we don't think that that
26:38
Speaker 1: expansion is still going on today. It happened and then
26:41
Speaker 1: it stopped happening. And we also need quantum fluctuations before
26:45
Speaker 1: inflation and during inflation, and then we needed to all
26:48
Speaker 1: somehow turn into the matter that we have today in
26:51
Speaker 1: the universe, right, and then also the structure and the
26:54
Speaker 1: way it's sort of arranged all that that we see today.
26:57
Speaker 1: And so a big idea that might explain this is
27:00
Speaker 1: this idea of an infloton, like a special particle that
27:04
Speaker 1: caused inflation. Yeah, that's basically the go to strategy for
27:07
Speaker 1: particle physicists. Right, It's like, well, we have some process,
27:10
Speaker 1: what causes it? A quantum field? Right, that's like the
27:13
Speaker 1: only thing we know how to put into the universe.
27:15
Speaker 1: And so the game of particle physics is sort of
27:18
Speaker 1: like what set of quantum fields can you put together
27:21
Speaker 1: that give you the behavior that we see, Like for electrodynamics,
27:25
Speaker 1: for you know, electricity and magnetism, we see, Well, if
27:28
Speaker 1: we make a photon field and an electron field and
27:30
Speaker 1: we have them talk to each other this way, does
27:32
Speaker 1: that reproduce what we see in the universe? And so
27:35
Speaker 1: now we have a set of requirements, and so people
27:37
Speaker 1: have built this field. It's called the infloton field, and
27:40
Speaker 1: it's a quantum field that fills the whole universe. And
27:43
Speaker 1: like other quantum fields, you know, it can contain energy
27:47
Speaker 1: and it can have particles in it. These would be
27:49
Speaker 1: Inflaton particles. And they try to construct this field in
27:53
Speaker 1: a way that satisfies all those requirements we just mentioned,
27:56
Speaker 1: a rapid expansion, a stop to the rapid expansion and
27:59
Speaker 1: allowing some quantum fluctuations and then turning into regular matter. Interesting,
28:04
Speaker 1: so really you're sort of inserting a new field. That's
28:06
Speaker 1: sort of the more sort of proper way to do
28:08
Speaker 1: it theoretically. And did you consider just calling it the infield?
28:15
Speaker 1: I stopped short at making that idea. That idea comes
28:21
Speaker 1: out of left field, or yeah, it's a deep field idea.
28:25
Speaker 1: So this field might explain things, and so how does
28:28
Speaker 1: this explain inflation? Like how can field do that? And
28:31
Speaker 1: why did it stop suddenly? Why isn't it also expanding
28:34
Speaker 1: things today? So to understand how a field can do that,
28:36
Speaker 1: we need to think about what it means for a
28:38
Speaker 1: field to be vacuum, Like when we talk about empty space,
28:41
Speaker 1: or the vacuum. What we really mean is that space
28:44
Speaker 1: has no particles in it, no like little objects flying
28:48
Speaker 1: around carrying kinetic energy, energy of motion. We don't mean
28:51
Speaker 1: that it can't have any potential energy, right like we
28:54
Speaker 1: think that empty space is filled with quantum fields, and
28:57
Speaker 1: those fields do have energy in them. For example, the
29:00
Speaker 1: Higgs field is a field that fills all of space,
29:03
Speaker 1: but at its lowest level, as most relaxed point, it
29:07
Speaker 1: still has energy in it that's potential energy. And so
29:10
Speaker 1: people think that maybe the in phloton field was some
29:13
Speaker 1: field that started out with a lot of potential energy,
29:16
Speaker 1: no matter at all, no particles, just a lot of
29:19
Speaker 1: potential energy. An interesting thing about a quantum field that
29:23
Speaker 1: has just potential energy is that it causes rapid expansion
29:28
Speaker 1: of space time. And this is an idea we've run
29:31
Speaker 1: into before when we've talked about dark energy. One way
29:34
Speaker 1: we try to explain why the universe seems to be
29:37
Speaker 1: accelerating its expansion today is this idea of a cosmological constant,
29:42
Speaker 1: which is just like a potential energy that fills all
29:45
Speaker 1: of space. If you put that into the equations of
29:47
Speaker 1: general relativity, it creates this negative pressure which expands all
29:52
Speaker 1: of space. And so just like adding a cosmological constant
29:55
Speaker 1: sort of makes the universe accelerate its expansion. Now, if
29:59
Speaker 1: you create a quantum field very early in the universe
30:02
Speaker 1: with a lot of potential energy, it has the same effect. Well,
30:06
Speaker 1: I guess let me step back a little bit. So
30:08
Speaker 1: there's the idea that maybe that the universe is filled
30:10
Speaker 1: with fields like the electron field, the court fields, and
30:14
Speaker 1: the all the particles have their own fields, and these
30:17
Speaker 1: are like sort of like the things that just perme
30:19
Speaker 1: It's sort of like a fog that fills every every
30:21
Speaker 1: bit of space in the universe. And you're saying that
30:24
Speaker 1: just having a field with energy in it expands space.
30:28
Speaker 1: That's right. Every quantum field has to have energy in it.
30:31
Speaker 1: That's called this zero point energy, and we've talked about
30:34
Speaker 1: it in the podcast before, like it manifests itself as
30:36
Speaker 1: the Casimir effect and other areas. And so we think
30:40
Speaker 1: that every quantum field has a minimum energy in it,
30:43
Speaker 1: and any field with energy this is always expanding space.
30:46
Speaker 1: So why is that? Why does space itself expand when
30:50
Speaker 1: that the field has energy? Space itself will expand when
30:53
Speaker 1: a field has potential energy, Right when it's in the
30:56
Speaker 1: vacuum state when it has any sort of potential energy,
30:58
Speaker 1: because that's the way it enters into the equations for
31:01
Speaker 1: general relativity. General relativity is a way to understand the
31:04
Speaker 1: effect of matter and energy on space, and mostly it's
31:08
Speaker 1: pretty simple, like you put a blob of mass into space,
31:11
Speaker 1: it will curve space. That makes sort of sense because
31:13
Speaker 1: you can imagine that it changes like the way things
31:16
Speaker 1: fly and why photons get bent around the Sun, etcetera.
31:19
Speaker 1: And that's also true for energy. You put a lot
31:21
Speaker 1: of energy into space, it will curve it. But there
31:23
Speaker 1: also are other effects that go beyond sort of like
31:26
Speaker 1: the simple replication of Newton's Gravity can also do other
31:29
Speaker 1: weird things, it turns out, and one of those weird
31:32
Speaker 1: things is that if you have potential energy all throughout space,
31:35
Speaker 1: it creates this negative pressure. And negative pressure is really
31:39
Speaker 1: weird because it's like repulsive gravity. We're used to gravity
31:43
Speaker 1: only attracting things like you are attracted to the Earth
31:46
Speaker 1: and the Earth is attracted to the Sun. Well, Einstein's
31:49
Speaker 1: general relativity tells us that gravity comes from this distortion
31:52
Speaker 1: of space and time, and then it's sensitive not just
31:55
Speaker 1: to mass, but also to potential energy, but potential energy
31:59
Speaker 1: does something really really weird, that sort of unfamiliar and
32:02
Speaker 1: hard to grapple with, which is that it creates this repulsion,
32:05
Speaker 1: this negative pressure, which expands space itself. And you might ask, well, look,
32:10
Speaker 1: why does it do that? And you know, I don't
32:12
Speaker 1: have a great clear answer for you. It's just sort
32:14
Speaker 1: of like that's the structure the equations in general relativity,
32:16
Speaker 1: which seem to describe what we see. And Einstein, when
32:20
Speaker 1: he first saw this in his equation, he thought, well,
32:22
Speaker 1: that's nonsense. Let's just ignore that, because there's no way
32:25
Speaker 1: the universe is doing that, right, And so he overlooked
32:28
Speaker 1: this idea of a cosmological constant any sort of repulsive gravity,
32:32
Speaker 1: And now we sort of needed to describe the universe
32:35
Speaker 1: that we see. We don't exactly know why that happens,
32:38
Speaker 1: but it's just sort of like the shape of the
32:40
Speaker 1: equations that we can use to describe what we are seeing.
32:43
Speaker 1: M I see. So it's sort of like fields of
32:45
Speaker 1: energy and that puts pressure on the universe to make
32:48
Speaker 1: it expand, sort of like air inside of a balloon. Maybe,
32:51
Speaker 1: like if you have a lot of pressure a lot
32:53
Speaker 1: of energy inside of the balloon that those tend to
32:55
Speaker 1: want to expand the space it's in. Right, Yeah, that's
32:58
Speaker 1: a fine way to think about it. And so if
33:00
Speaker 1: you want to describe the universe as expanding very very rapidly,
33:04
Speaker 1: you need to have a field that has a huge
33:06
Speaker 1: amount of potential energy. And so this can be like
33:09
Speaker 1: a vacuum. We're talking about no particles, but still a
33:12
Speaker 1: field with a lot of energy. And sometimes we call
33:14
Speaker 1: this in particle physics, we call this a false vacuum
33:17
Speaker 1: because it's not like energy equal zero. We talked about
33:20
Speaker 1: this before in terms of the Higgs field. Higgs field
33:22
Speaker 1: is the field that has energy in it, some vacuum
33:25
Speaker 1: expectation value. It's it's relaxed. It's sort of like at
33:28
Speaker 1: its lowest state, but that lowest state is not at
33:30
Speaker 1: zero energy. And that's why all the particles have mass,
33:34
Speaker 1: because they interact with this field which has this energy,
33:36
Speaker 1: and that's where the energy for the mass of all
33:38
Speaker 1: the particles comes from. So it seems like, you know,
33:41
Speaker 1: we have all these fields to describe all these particles,
33:43
Speaker 1: and they're all trying to make space bigger all the time.
33:46
Speaker 1: But we're now we're trying to explain this particular period
33:48
Speaker 1: in the in the universe's history where it thinks inflated
33:51
Speaker 1: exploded expand its super fast and the super joid amount
33:54
Speaker 1: of time. And so maybe the theory is that maybe
33:56
Speaker 1: there was a field with a huge amount of energy
33:59
Speaker 1: at that point, then that caused that huge expansion exactly.
34:02
Speaker 1: So when this field has a huge amount of potential energy,
34:05
Speaker 1: you get rapid expansion of space and time. But remember
34:08
Speaker 1: we need not just rapid expansion of space time, we
34:11
Speaker 1: also need that to stop, right, because we don't think
34:13
Speaker 1: inflation is still happening today. So the idea is that
34:17
Speaker 1: instead of this potential energy being stable, you know, instead
34:20
Speaker 1: of this being like a field that's sort of like
34:22
Speaker 1: stuck in a well, that it's sort of like unstable,
34:25
Speaker 1: that it's like a boulder the top of a hill,
34:27
Speaker 1: and that hills like a little bit slanted. So eventually
34:30
Speaker 1: the universe rolls down from the top of this high
34:33
Speaker 1: potential energy into a state with lower potential energy. And
34:37
Speaker 1: just like when a boulder rolls down a hill, it
34:39
Speaker 1: turns some of that gravitational potential energy into the energy
34:43
Speaker 1: of its motion, right, And so in this case, what
34:45
Speaker 1: would happen is that potential energy in that field, that
34:48
Speaker 1: infloton field, which was driving the expansion of the universe.
34:52
Speaker 1: Now that potential energy decreases, so the universe's expansion stops
34:56
Speaker 1: and that energy has to go somewhere, So it creates
34:58
Speaker 1: inflot on part of goals. So you go from a
35:01
Speaker 1: vacuum with a lot of potential energy to something which
35:04
Speaker 1: is no longer vacuum because you have all this energy
35:06
Speaker 1: and all these infloton particles which are whizzing through space
35:09
Speaker 1: right right. Well, I'm not sure a bolder is helping
35:12
Speaker 1: me understand this as much, but I think what you're
35:14
Speaker 1: saying is that it had all this energy, it caused
35:17
Speaker 1: the universe to inflate super rapidly, and then it was
35:19
Speaker 1: basically like spent, right Like it just diluted. Once space
35:23
Speaker 1: expanded that fast, it just basically all that energy went away,
35:26
Speaker 1: sort of like maybe a balloon once to pop it
35:28
Speaker 1: the pressure so it dissipates, But the energy doesn't go away.
35:31
Speaker 1: It just turns into infloton particles. It goes from one
35:34
Speaker 1: kind of energy into another kind of energy. It goes
35:37
Speaker 1: from high potential energy into energy of these particles. Why
35:41
Speaker 1: don't the particles cause inflation? Though, because those particles are
35:44
Speaker 1: now mass and energy, which has a different effect on
35:47
Speaker 1: the shape of the universe. You only get that kind
35:49
Speaker 1: of rapid inflation when you have high potential energy. Now,
35:52
Speaker 1: when you have a lot of mass, right, mass itself
35:54
Speaker 1: doesn't cause accelerated expansion of the universe. Only potential energy
35:58
Speaker 1: does that. Sort of like the energy went from one
36:00
Speaker 1: field to another field, right, yeah, where the field itself change.
36:03
Speaker 1: It used to be that the field had a lot
36:04
Speaker 1: of potential energy, and now it doesn't have a lot
36:06
Speaker 1: of potential energy, and so that energy goes into something else.
36:10
Speaker 1: Just like that boulder. You know, it had a lot
36:12
Speaker 1: of potential energy when it's sitting up on the top
36:14
Speaker 1: of a hill, and then when it falls off the hill,
36:16
Speaker 1: that energy is still there, but now it's like the
36:18
Speaker 1: energy of the motion of the boulder. So you can
36:20
Speaker 1: turn energy from one kind of thing into another kind
36:22
Speaker 1: of thing. Like you can take this potential energy and
36:24
Speaker 1: create particles out of it. So you went from this
36:27
Speaker 1: state of high potential energy, which is inflating the universe,
36:31
Speaker 1: into a state of lower potential energy. Now inflation has stopped,
36:34
Speaker 1: the expansion has stopped, and you're filled with all these
36:36
Speaker 1: crazy inflaton particles. But also, I mean, I imagine some
36:39
Speaker 1: of it has to do with the dilution of it, right,
36:41
Speaker 1: because space expanded, now suddenly it's sort of less powerful too,
36:45
Speaker 1: whatever energy was there. Yeah, although it's really tricky to
36:48
Speaker 1: think about the conservation of energy in these terms. Remember
36:51
Speaker 1: we had a whole podcast about whether energy is conserved
36:53
Speaker 1: and it's not actually conserved when space is expanding, because
36:57
Speaker 1: sometimes more energy is being created. Right, as you create
37:00
Speaker 1: more space, you also create more energy. But you're right
37:03
Speaker 1: that the energy is getting diluted because we went from
37:05
Speaker 1: very hot, dense universe to one that's not very hot
37:08
Speaker 1: and not very dense. I see, all right, Well that
37:12
Speaker 1: might be then where all of the energy from inflation
37:15
Speaker 1: went to and why the universe stopped expanding so quickly.
37:19
Speaker 1: So it might be this imfloton. And so let's get
37:21
Speaker 1: into more of this particle and whether or not it's
37:24
Speaker 1: real and whether we've seen it. But first let's take
37:27
Speaker 1: another quick break. All right, Daniel, we are inflating people's
37:42
Speaker 1: minds here today talking about inflation and the inflaton, which
37:46
Speaker 1: might explain the rapid expansion of the universe during the
37:49
Speaker 1: Big Bang. So I guess the question is we have
37:51
Speaker 1: this theory of the infloton and the inflaton field, is
37:54
Speaker 1: it real, like, have we seen it? Do we have
37:56
Speaker 1: confirmation that it exists. It's a great question and it's
37:59
Speaker 1: one that we are still struggling with. You know, first
38:02
Speaker 1: you come up with these ideas and then you think
38:04
Speaker 1: about their consequences. Then you think about ways to test them.
38:07
Speaker 1: And we have some promising ways to maybe explore this
38:11
Speaker 1: because we can think about what happened to those infloton particles, right,
38:15
Speaker 1: the universe expanded, all that potential energy turned into infloton particles,
38:19
Speaker 1: but those infloton particles are not still around today. The
38:22
Speaker 1: universe is not filled with infloton particles. We think what
38:25
Speaker 1: happened is that those particles then turned into normal matter,
38:29
Speaker 1: you know, quarks and electrons and all kinds of stuff,
38:31
Speaker 1: which then led to the universe we see today. And
38:34
Speaker 1: so we might be able to trace back and say, well,
38:37
Speaker 1: can we see evidence in sort of the patterns of
38:39
Speaker 1: those corks and those electrons that support that they came
38:43
Speaker 1: from in photons, that their history is sort of in photons?
38:47
Speaker 1: WHOA wait, are you saying that a lot or most
38:50
Speaker 1: or some of the matter that we see till they
38:52
Speaker 1: came from this energy that exploded the universe directly. If
38:55
Speaker 1: this theory is correct, it would be all of it,
38:57
Speaker 1: every little piece of matter which exists to day, came
39:01
Speaker 1: from an infloton, Every cork, every electron, every timing thing
39:04
Speaker 1: out there used to be an infloton particle, used to
39:07
Speaker 1: be the whole universe just was this. All it was
39:10
Speaker 1: was the infhoton field and infloton particles, and then all
39:13
Speaker 1: of those turned into the matter that makes us up right,
39:17
Speaker 1: But through these other fields, are you saying those other
39:19
Speaker 1: fields didn't exist or they didn't have energy before. How
39:22
Speaker 1: does this relate to the other quantum fields that we
39:24
Speaker 1: see today. That's a great question. And we have to
39:26
Speaker 1: remember that our picture of these fields electrons and quarks
39:30
Speaker 1: and whatever is something we've only really ever seen when
39:33
Speaker 1: the universe is cold and old, and so it's like
39:37
Speaker 1: a useful description of how things work. We don't think
39:40
Speaker 1: it's fundamental. We don't think that these this is like
39:42
Speaker 1: the basic description of true reality is just sort of
39:45
Speaker 1: like the physics that works today. It's sort of like
39:47
Speaker 1: if you wanted to describe the physics of fluids, you
39:50
Speaker 1: know how do fluids flow. Well, that works when fluids
39:53
Speaker 1: are a certain temperature. When fluids get really really hot,
39:55
Speaker 1: and all those equations go out the window, and when
39:57
Speaker 1: fluids get really really cold, those equations go out the window.
40:01
Speaker 1: So one idea is not that sort of the in
40:04
Speaker 1: photon fields and these fields, the cork fields, and the
40:06
Speaker 1: electron fields all exist at the same time, but that
40:09
Speaker 1: when the universe is hot and dense and crazy, the
40:12
Speaker 1: in photon field is the way to describe the universe.
40:15
Speaker 1: And then later when it gets colder, a picture of
40:18
Speaker 1: the same universe is to use these fields that we
40:20
Speaker 1: have today. None of these fields are like a deep,
40:22
Speaker 1: fundamental true story. They're just sort of like an effective
40:25
Speaker 1: mathematical story we tell about today's situation. It's like the
40:29
Speaker 1: story changes kind of first it had these characters, and
40:32
Speaker 1: then and then these and then it had these other
40:35
Speaker 1: characters in it. Yeah, And physicists talk about this as
40:37
Speaker 1: a phase change for a reason, right, Because when phases
40:39
Speaker 1: of matter change, different rules seem to come into play. Right.
40:43
Speaker 1: There's different rules about how crystals work and how plasmas
40:46
Speaker 1: work and how fluids work for a reason. And so
40:48
Speaker 1: because we don't have a fundamental theory of the universe.
40:51
Speaker 1: We can just describe it in terms of different phases.
40:53
Speaker 1: We think the universe at a very hot, dense temperature
40:55
Speaker 1: in the bay beginning is described by different physics, and
40:58
Speaker 1: that's the in ploton field. The universe today is described
41:01
Speaker 1: by the physics that we have been developing. Interesting, you're
41:05
Speaker 1: saying that sort of at the very at the very
41:06
Speaker 1: beginning of the universe, when it expanded and it was
41:09
Speaker 1: super hot and dance and it was expanding super fast,
41:11
Speaker 1: then the star of the show was this infloton field,
41:14
Speaker 1: and in ploton particles were flying all around, and then
41:17
Speaker 1: the story changed and then those became sort of what
41:19
Speaker 1: we see today. Yeah, exactly, like the universe sort of
41:22
Speaker 1: cooled down and crystallized and new stuff happened, and that
41:25
Speaker 1: stuff is well described by having electrons and quirks and
41:28
Speaker 1: all that kind of stuff. You were saying, we're living
41:30
Speaker 1: in the reboot of the universe with a new cast. Yeah,
41:33
Speaker 1: we're living in the ice ages. Man. You know, the
41:35
Speaker 1: most dramatic thing happened, you know, in Act one, and
41:38
Speaker 1: we're in like Act fourteen billion, and everything is cold
41:41
Speaker 1: and desolate, except that we don't know this might go
41:43
Speaker 1: into syndication for another unred trillion seasons. That's right, we
41:47
Speaker 1: should be so lucky as to have fourteen billion seasons.
41:51
Speaker 1: So tell me about this inflaton, I guess, is it
41:53
Speaker 1: just like any other particle? Could you make things out
41:55
Speaker 1: of this infloton? Like was there imfloton matter at the
41:59
Speaker 1: beginning of the universe during the Big Bang? So this
42:01
Speaker 1: is the wild West of theoretical physics. There's lots of
42:03
Speaker 1: different ideas for these in photons, what they could look like,
42:06
Speaker 1: how they work, what mass they even have, whether their
42:09
Speaker 1: mass really even makes sense, because in some sense, the
42:12
Speaker 1: mass of a particle depends on how it moves, which
42:15
Speaker 1: depends on the potential energy. And here we're talking about
42:19
Speaker 1: potential energy that's changing, and so like you know, these
42:21
Speaker 1: in photon particles might have variable mass, or they might
42:25
Speaker 1: be ridiculously massive, you know, like trillions of times the
42:28
Speaker 1: mass of the proton, or they could be as light
42:31
Speaker 1: as the Higgs boson. So there's basically every flavor of
42:34
Speaker 1: in photon theory out there, depending on the one that
42:37
Speaker 1: you like. There's inflation in the number of theories about
42:40
Speaker 1: the inton. But that's what happened in physics. Right, there's
42:44
Speaker 1: a big problem. Nobody knows what to do. Somebody creates
42:46
Speaker 1: a sort of new class of idea and all of
42:49
Speaker 1: a sudden it opens up the door at to lots
42:51
Speaker 1: more creativity. People say, oh, maybe it's this. Maybe it's like, oh,
42:54
Speaker 1: look what I did with this. If I just tweaked
42:55
Speaker 1: this over here, I get something totally different which has
42:57
Speaker 1: these exciting properties. So that's sort of like a gold
43:00
Speaker 1: rush when it comes to theoretical physics, and this is
43:02
Speaker 1: now a huge area of research. But one thing that
43:05
Speaker 1: people are working on is trying to imagine if we
43:08
Speaker 1: can see evidence for these particles if they left an
43:11
Speaker 1: imprint on the universe today. Interesting, well, I guess couldn't
43:14
Speaker 1: we recreate some of these conditions, Like when you're smashing particles,
43:18
Speaker 1: don't you create you know, the matter and energy density
43:22
Speaker 1: to the point where you might see an infloton or something.
43:24
Speaker 1: That's exactly the goal, And that is why we do
43:27
Speaker 1: collider physics, because we want to probe the universe not
43:30
Speaker 1: just at the cold, boring temperature that it is today,
43:32
Speaker 1: but as far back as we can go. But you know,
43:34
Speaker 1: our colliders are limited, and so we can create things
43:37
Speaker 1: that are sort of warm compared to a typical environment,
43:39
Speaker 1: but we can't get anywhere near the energies necessary to
43:42
Speaker 1: create an infloton particle unless we build something like the
43:45
Speaker 1: size of the galaxy. Then again, we don't really know
43:49
Speaker 1: the mass of this thing, and we don't really know
43:50
Speaker 1: what the rules are, so it could also just be
43:53
Speaker 1: around the corner we build a collider twice as big
43:55
Speaker 1: as we have now, maybe we make infloton particles. We
43:58
Speaker 1: don't know, Like most people suspect that it is somewhere
44:01
Speaker 1: up near the plank mass, and so you'd need some
44:03
Speaker 1: ridunculously large particle accelerator to ever recreate these conditions. I
44:08
Speaker 1: guess you know that the imploton existed when the universe
44:11
Speaker 1: was tend to the negative thirty times smaller. That they
44:14
Speaker 1: might have existed right up until the very end of
44:16
Speaker 1: that range, right, in which case we might be right
44:18
Speaker 1: over the range where you could see them. Yeah, Or
44:20
Speaker 1: you might need an accelerator that's tended the thirty times
44:23
Speaker 1: bigger than hours in order to see it, which might
44:25
Speaker 1: cost tend to the times exactly. So we might need
44:29
Speaker 1: to wait for financial inflation of research budgets before we
44:32
Speaker 1: can probe that. So then could we ever test whether
44:35
Speaker 1: this imfloton exists or do we have to rely on
44:38
Speaker 1: theoretical work. We can test to see if it left
44:40
Speaker 1: an imprint on the universe, because you know, the way
44:44
Speaker 1: to see whether something happened a long time ago is
44:46
Speaker 1: just to look for clues. If you can't recreate the events,
44:49
Speaker 1: you look to see if it left a mark on
44:51
Speaker 1: the universe. And one of those marks might be, for example,
44:54
Speaker 1: gravitational waves. You know, any time you have expansion of
44:58
Speaker 1: space that way, you're going to create ripples in space itself.
45:03
Speaker 1: So there are theories about the gravitational waves that were
45:06
Speaker 1: left by inflation, and so we listen really really carefully
45:10
Speaker 1: for these gravitational waves. We might be able to detect
45:12
Speaker 1: those that come from the very early universe. And we
45:15
Speaker 1: had an episode about this cosmic gravitational background and whether
45:19
Speaker 1: advanced detectors could detect it. And so there are promising
45:23
Speaker 1: areas of research. They're interesting, like the echoes of the
45:26
Speaker 1: Big Bang in space itself, in space itself. So far,
45:29
Speaker 1: our detectors are only capable of hearing like extremely loud
45:33
Speaker 1: shouts and screams in space, you know, when huge black
45:35
Speaker 1: holes combined with each other. These would be more like whispers,
45:38
Speaker 1: much much quieter and also hard at a pinpoint. All right,
45:42
Speaker 1: They're not like an individual source, and so it takes
45:45
Speaker 1: a little bit more work. But it's possible that they
45:47
Speaker 1: could hear these things. If you're interested in those details,
45:49
Speaker 1: check out our episode on the cosmic gravitational background. And
45:52
Speaker 1: then I guess another quick question is, you know, is
45:55
Speaker 1: inflation related to the current expansion of the universe, like
45:58
Speaker 1: our current expansion be related or be a part of
46:02
Speaker 1: that inflation and maybe due to in photonstitute. We just
46:05
Speaker 1: don't know. I mean, we see that there is a similarity,
46:08
Speaker 1: that there was an expansion of space in the very
46:10
Speaker 1: early universe and this an expansion of space in the
46:12
Speaker 1: late universe. Remember that dark energy isn't sort of something
46:15
Speaker 1: that's been happening the whole time. We think it turned
46:18
Speaker 1: down about five billion years ago. So we don't understand
46:21
Speaker 1: like why in photons would be created now to cause
46:24
Speaker 1: that expansion. Some theories do connect them, that there are
46:27
Speaker 1: these theories of quintessence that suggests that the same field
46:30
Speaker 1: might be responsible for that and for these but fundamentally
46:33
Speaker 1: we just don't understand it. And we don't understand dark
46:35
Speaker 1: energy either. Right, We've tried to do these calculations to say, well,
46:39
Speaker 1: we see the universe is expanding, and that expansion is accelerating.
46:43
Speaker 1: We can measure how big a potential energy with cosmological
46:47
Speaker 1: constant you would need for that expansion, and then we
46:49
Speaker 1: try to explain that. We say, well, is there that
46:52
Speaker 1: much potential energy in the quantum fields of space? And
46:55
Speaker 1: we do the calculation and we get a number, and
46:57
Speaker 1: that number is tend the one hundred times too big.
47:01
Speaker 1: So we just don't understand the connection between quantum fields
47:05
Speaker 1: potential energy, and the expansion of space. Where like at
47:08
Speaker 1: the very very beginning, this is where we really need
47:10
Speaker 1: a theory of quantum gravity that would explain all this
47:13
Speaker 1: to us. I think I got it, Daniel, I think
47:15
Speaker 1: I know what happened. Oh and you waited to the
47:18
Speaker 1: end of the podcast to tell me. Yeah. I mean, clearly,
47:21
Speaker 1: the imflotons woke up, they did inflation, and then they
47:24
Speaker 1: took a nap, and they're just now waking up to
47:27
Speaker 1: cause expansion. I mean, I think that my nap theory
47:30
Speaker 1: explains at all. Isn't it the ten billion year nap?
47:32
Speaker 1: That's a great theory. I love that. What's a short
47:36
Speaker 1: nap if you consider that the universe might go on
47:38
Speaker 1: for trillions of years, it could be And there are
47:40
Speaker 1: also a few other ways we might get hints about
47:43
Speaker 1: whether the in photon was there. Other than just gravitational waves.
47:46
Speaker 1: People can look for even more details in this cosmic
47:49
Speaker 1: microwave background radiation. Remember that Bicep experiment that thought they
47:53
Speaker 1: saw evidence for in photons because of the sort of
47:56
Speaker 1: twists and turns in the cosmic microwave background radiation. And
48:00
Speaker 1: are folks looking at like correlations of where galaxies are
48:03
Speaker 1: in the sky to look for like triangle shapes which
48:06
Speaker 1: might come from the way the infloton decayed, Like three
48:09
Speaker 1: infloton particles might lead to like a trio of galaxies
48:13
Speaker 1: out there in space. So sort of like late structure
48:16
Speaker 1: of the universe and early wiggles in the universe were
48:19
Speaker 1: digging deep into those to look for evidence of these inflotons. Yeah,
48:23
Speaker 1: it's amazing how we're sort of like scraping the bottom
48:26
Speaker 1: of the barrel almost, or like we're trying to figure
48:28
Speaker 1: out the whole universe, this little tiny people that we
48:31
Speaker 1: have in our little corner of the universe. But it's
48:33
Speaker 1: all we've got, and it's amazing what we've been able
48:35
Speaker 1: to do so far. It's sort of like flabbergasting, you know.
48:38
Speaker 1: And the thing that's wonderful about that is that you
48:40
Speaker 1: can extrapolate forward and think, like, what will humans do
48:43
Speaker 1: in a hundred years or in five hundred years. We
48:45
Speaker 1: would be amazed the things that they might have learned
48:48
Speaker 1: from like tiniest little hints of the tiniest little photons
48:52
Speaker 1: that happened to land on our eyeballs. Yeah. I think
48:55
Speaker 1: we talked about this in our first book about how
48:57
Speaker 1: we're almost sort of going through a big bang in
49:00
Speaker 1: this sense of human knowledge about the universe. Right, Like
49:03
Speaker 1: if you look at the history of humanity, our knowledge
49:06
Speaker 1: about the universe and how what it's made out of
49:07
Speaker 1: and how it started and how it's range really sort
49:10
Speaker 1: of exploded in the last few hundred years, right, So
49:13
Speaker 1: we're sort of in the middle of this inflation of
49:16
Speaker 1: human exploration. That's right. We've been making a lot of
49:18
Speaker 1: progress in the last hundred years. And also physicists been
49:21
Speaker 1: taking more naps than the last hundred years, So maybe
49:23
Speaker 1: there's a connection there. Maybe it's gonna stop. Yeah, just
49:26
Speaker 1: like inflation is going to be a ten billion year nap. Daniel,
49:30
Speaker 1: you think, or when can we expect more progress if
49:32
Speaker 1: we have ten billion more dollars. Hey, I'll turn that
49:34
Speaker 1: into more science and you'll wake up. You'll wake up
49:36
Speaker 1: for ten billion dollars. But not less, no less than that.
49:40
Speaker 1: All right, Well, again, this is a fascinating theory. It's
49:43
Speaker 1: an incredible sort of idea that the universe expanded that
49:47
Speaker 1: fast and that quickly, and that we might have an
49:50
Speaker 1: explanation for it, and that it might just be another
49:52
Speaker 1: interesting way that quantum fields interact with space and sort
49:56
Speaker 1: of more like a class of explanations right now, because
49:59
Speaker 1: there's a lot of for an ideas. But it's really
50:01
Speaker 1: exciting that we have sort of a framework, a framework
50:04
Speaker 1: that predicts these crazy events that were now pretty sure
50:07
Speaker 1: did happen, and that let's just ask deeper questions about
50:10
Speaker 1: you know, why would that field exist and what could
50:12
Speaker 1: cause it? And you know what came before that field.
50:15
Speaker 1: And it's led to some really cool, crazy ideas like
50:17
Speaker 1: this single bounce theory of the universe, that the universe
50:20
Speaker 1: has been contracting for infinity down just before the Big
50:24
Speaker 1: Bang and then it bounced, and it will only bounce
50:26
Speaker 1: once after the big bang, and now we'll expand forever
50:30
Speaker 1: some really beautiful interesting ideas that just give you a
50:32
Speaker 1: different sense for the whole scope of the universe, right,
50:36
Speaker 1: or can that turn around too, and like keep bouncing
50:38
Speaker 1: through infinity? There are multiple infinite bounced theories. But also
50:42
Speaker 1: there's this new theory of a single bounce, which I
50:44
Speaker 1: find sort of cool. I see no more naps. I
50:47
Speaker 1: guess physics will find a way physically. That's right. We'll
50:50
Speaker 1: leave that to the engineers, maybe let them figure it
50:53
Speaker 1: that out. But yeah, it's sort of amazing to think
50:55
Speaker 1: about the beginning of the universe because a lot has
50:58
Speaker 1: happened since. So then next time you look around you
51:01
Speaker 1: and think about the things that are around you and
51:03
Speaker 1: the stuff you're sitting on or writing in, think about
51:06
Speaker 1: how it all came from this incredible state that the
51:09
Speaker 1: universe was in, and how maybe we all came from
51:12
Speaker 1: in photons. And maybe one day we'll discover the chicken
51:15
Speaker 1: that laid that egg, that growed to be that chicken
51:17
Speaker 1: that laid that egg, and get all the way back
51:19
Speaker 1: to something which sort of makes sense on its own
51:21
Speaker 1: and doesn't require an explanation, or maybe not. Maybe we'll
51:24
Speaker 1: just keep digging forever. Right, Maybe was the chicken ton,
51:28
Speaker 1: the plan, the foul on? Well, we hope you enjoyed that.
51:32
Speaker 1: Thanks for joining us, see you next time. Thanks for listening,
51:43
Speaker 1: and remember that Daniel and Jorge explained. The Universe is
51:46
Speaker 1: a production of I Heart Radio. Or more podcast from
51:49
Speaker 1: my heart Radio, visit the I heart Radio app, Apple Podcasts,
51:53
Speaker 1: or wherever you listen to your favorite shows. No