Latest / Daniel and Kelly’s Extraordinary Universe / Listener Questions 11: Deep questions about gravity and particles.

Transcript

Listener Questions 11: Deep questions about gravity and particles. · Daniel and Kelly’s Extraordinary Universe

0:08
Speaker 1: Hey, Daniel, how's our email inbox looking these days? Oh? Man,
0:11
Speaker 1: like usual, it is jammed full. We have a big
0:15
Speaker 1: pile of questions. Really, people still have questions. You thought
0:18
Speaker 1: maybe we'd like answered all the questions in the interview. Well,
0:21
Speaker 1: we have done about two episodes and ten listener question episode.
0:25
Speaker 1: I figured, you know, eventually people might be satisfied and
0:28
Speaker 1: know all the answers to the universe. I think that
0:30
Speaker 1: the more we answer people's questions, the more questions they have.
0:33
Speaker 1: Man sciences like that, isn't it always teasing you with
0:36
Speaker 1: an answer and then dropping more questions? And thank goodness,
0:39
Speaker 1: otherwise we would run out of episodes and then we
0:42
Speaker 1: wouldn't be here. Hi am more handmaker, tunist and the
1:00
Speaker 1: creator of PhD comics. Hi. I'm Daniel. I'm a particle
1:03
Speaker 1: physicist and I'm a professional email question answer. Wow. Really
1:07
Speaker 1: you get paid for that? I just feel like a
1:10
Speaker 1: professional what I'm doing it. I feel like that's what
1:12
Speaker 1: I have to do to get paid, which I don't
1:13
Speaker 1: do very well, but which probably explains a lot. But
1:16
Speaker 1: sometimes people write into the podcast and I think this
1:18
Speaker 1: might be the only time this person has asked the
1:22
Speaker 1: question to a physicist and gone an answer. So I
1:24
Speaker 1: feel a little bit like I'm representing physics in some way. Wow,
1:28
Speaker 1: you're the ambassador of the physics nation a little bit. Yeah,
1:32
Speaker 1: So I feel some responsibility to know, be polite and
1:35
Speaker 1: funny and insightful and all that stuff. You know. It's
1:38
Speaker 1: like that first day of class in college. Sometimes I
1:40
Speaker 1: get to teach freshman and I am on the first Monday,
1:43
Speaker 1: and I feel like, Wow, I am college for them.
1:46
Speaker 1: So there's a bit of pressure there. Yeah, and if
1:47
Speaker 1: someone walks out, you're like, well, I guess I failed physics.
1:53
Speaker 1: Nobody walks out on my emails fortunately, But anyways, welcome
1:57
Speaker 1: to our podcast. Daniel and Jorge explained the Universe but
2:00
Speaker 1: suction of I Heart Radio, in which we tackle all
2:02
Speaker 1: the questions in the universe, all the things that science
2:05
Speaker 1: wants to know and all the things that everybody wants
2:08
Speaker 1: to know. How did the universe begin, what is it
2:10
Speaker 1: made out of? How is it going to end? Why
2:12
Speaker 1: are we all here? And should you eat your bananas
2:14
Speaker 1: when they're black or green? That's right, it's a very
2:17
Speaker 1: important physics question. What can kill me out there? Daniel?
2:20
Speaker 1: And how? And when? Basically everything can kill you out
2:23
Speaker 1: there if you're creative about it. Love, Love can't kill you, Daniel.
2:27
Speaker 1: Have you seen Titanic? Soh, alright, love can kill Leonardo
2:31
Speaker 1: to keep you but exactly anyways, Yeah, it's our podcast
2:35
Speaker 1: where we talk about the universe and all the amazing
2:38
Speaker 1: things in it, and we also talk about the questions
2:40
Speaker 1: that not only scientists and physicists have at the cutting
2:43
Speaker 1: edge of knowledge and research, but also the questions that
2:46
Speaker 1: everyday people have about how things work and why things
2:49
Speaker 1: are the way they are. That's right, because questions belong
2:52
Speaker 1: to everybody, and asking questions is part of being human.
2:55
Speaker 1: It's impossible to be a conscious being in this world
2:57
Speaker 1: and I'll look around you and wonder why things are
3:00
Speaker 1: the way they are, why they aren't different, and what
3:02
Speaker 1: it means about the way the universe works. And scientists
3:05
Speaker 1: are just like that. They're just people who have answered
3:08
Speaker 1: more of their questions so far, and they're onto the
3:10
Speaker 1: most interesting cutting edge questions. And so our goal today
3:14
Speaker 1: is to bring you up to speed, to introduce you
3:17
Speaker 1: to the forefront of knowledge and tell you all about
3:19
Speaker 1: the questions that scientists are asking. And it turns out
3:22
Speaker 1: the scientists are asking a lot of the same questions
3:25
Speaker 1: that you are. It's right. Are you trying to tell
3:26
Speaker 1: me not to look to scientists for answers, Daniel, I
3:29
Speaker 1: just look to them for more questions. I'm trying to
3:31
Speaker 1: tell you that we're all scientists, were all asking these
3:33
Speaker 1: deep questions about the universe, and we'd all like to
3:36
Speaker 1: know the answer. Great. So to be on the program,
3:38
Speaker 1: we'll be doing another one of our famous listener question
3:41
Speaker 1: episodes where we answer questions from listeners. So to be
3:44
Speaker 1: on the podcast, we'll be tackling listener questions number eleven eleven. No,
3:54
Speaker 1: we've answered a lot of these and we have a
3:55
Speaker 1: big pile left, So if you've submitted your question and
3:59
Speaker 1: haven't gotten answer yet, stay tuned. We're getting to them.
4:01
Speaker 1: We love these listener Questions episodes, and I always love
4:04
Speaker 1: these episodes because people sending the most interesting questions. These
4:07
Speaker 1: are the really fun ones. People writing questions all the
4:10
Speaker 1: time the email, and sometimes I'll fire off a quick answer,
4:13
Speaker 1: but if it's a really good, juicy question that I
4:15
Speaker 1: think a lot of people would like to hear the
4:16
Speaker 1: answer to, or Brinkley, I need a little bit of
4:19
Speaker 1: time to research, and then we'll do it on the
4:21
Speaker 1: podcast cool. So today we have three pretty cool questions
4:25
Speaker 1: from listeners from all over the world, and they have
4:28
Speaker 1: to do with gravitational waves about the nature of matter
4:33
Speaker 1: and whether or not you can have a different kind
4:36
Speaker 1: of star than the ones that we are used to.
4:39
Speaker 1: So let's jump right into it, Daniel, and let's start.
4:42
Speaker 1: But this first question from Henrik Sumberg from Sweden, who
4:45
Speaker 1: asks can a gravitational wave kill you? Or what will
4:50
Speaker 1: you feel when you're close to a wave like the
4:52
Speaker 1: one that was found by Ligo. Wow? What an awesome
4:56
Speaker 1: question and a little terrifying. You know, do we thought
5:00
Speaker 1: about gravitation with dying from gravitational waves which I just
5:04
Speaker 1: assume we're rolling through us, but apparently they can kill us?
5:07
Speaker 1: Can they kill us? Because that's a question? Well, it
5:09
Speaker 1: is a great question. You know. These things are ripples
5:12
Speaker 1: in space itself, and it's cool that we build observatories
5:15
Speaker 1: that can spot them. But the ones that we've seen
5:18
Speaker 1: so far are really far away, so it's a totally
5:20
Speaker 1: valid question to ask what would happen if you got
5:23
Speaker 1: close to it? I guess it's kind of like asking, like,
5:25
Speaker 1: can of an ocean wave kill you? Right? I suppose?
5:28
Speaker 1: I mean ocean waves certainly can kill you. I think
5:30
Speaker 1: it's more like asking, you know, can the sun kill you?
5:33
Speaker 1: And the answer is basically the same as from a
5:35
Speaker 1: great distance, the sun will just make it nice and toasty,
5:38
Speaker 1: but if you get too close to almost anything, it'll shrick. Well,
5:41
Speaker 1: let's maybe recap for people who don't know. So gravitational
5:44
Speaker 1: wave is like a wave with like a ripple in
5:47
Speaker 1: spacetime itself. That's right. And the idea is that gravitational
5:51
Speaker 1: information doesn't move instantly, like if the Sun disappeared, we
5:56
Speaker 1: would still feel it's gravity for the eight minutes it
6:00
Speaker 1: look for that information to get to us, because gravitational
6:03
Speaker 1: fields ripple, right, you delete something from the universe, then
6:07
Speaker 1: the information propagates out the field itself ripples. Right, It's
6:11
Speaker 1: not instantaneous because nothing instantaneous in the universe exactly, nothing
6:15
Speaker 1: is instantaneous. No information can move faster than the speed
6:19
Speaker 1: of light. And so gravitational waves are when you have
6:22
Speaker 1: really strong, very powerful objects that are accelerating around each other,
6:26
Speaker 1: so they're making waves in space itself. Remember, gravity is
6:30
Speaker 1: just the bending of space. You put the Sun in
6:33
Speaker 1: the center of the Solar system, it bends the space
6:36
Speaker 1: around it, so that the Earth's most natural path is
6:39
Speaker 1: one to move in a circle around the Sun. And
6:42
Speaker 1: so when you move masses around, when you accelerate them
6:44
Speaker 1: back and forth around each other, it makes these waves
6:47
Speaker 1: in space. And that's what gravitational waves are there, like
6:50
Speaker 1: the contracting or the pulling on space itself. It's it's
6:53
Speaker 1: really kind of bonkers, like the changes in the gravitational field.
6:58
Speaker 1: Kind of Yeah, you can think about it two different ways.
7:00
Speaker 1: If you like to think of space is flat and
7:02
Speaker 1: having gravitational fields in it, then you can think of
7:05
Speaker 1: it as the rippling of those gravitational fields in space.
7:08
Speaker 1: But if you like to think about it like Einstein did,
7:10
Speaker 1: then you know there is no gravity. There's just sort
7:13
Speaker 1: of changes in the shape of space. And from that perspective,
7:16
Speaker 1: gravitational waves are ripples in the shape of space, like
7:20
Speaker 1: things get closer and then further apart, and closer and
7:23
Speaker 1: further apart. That's what happens when a gravitational wave passes
7:26
Speaker 1: you by, And I guess that we're like a wash
7:29
Speaker 1: in gravitational waves. Like if I move my arm around
7:32
Speaker 1: in a circle, I'm creating gravitational waves. But they're just
7:35
Speaker 1: so small that nobody can notice. That's right. Just like
7:39
Speaker 1: there's gravity between you and your arm, and you and
7:41
Speaker 1: that box in front of you, and you and that banana,
7:44
Speaker 1: you just can't feel it because gravity is just so weak.
7:47
Speaker 1: Anytime an object with mass moves and accelerates, it generates
7:51
Speaker 1: a gravitational wave, but because gravity is so weak, you
7:54
Speaker 1: usually just can't sense it. We can only sense gravitational
7:57
Speaker 1: waves from really really big thing things, really massive things,
8:01
Speaker 1: precisely because gravity is so weak. It's almost kind of
8:04
Speaker 1: like we're all swimming in like a thick Google or
8:07
Speaker 1: something like if space was a Google and we're all
8:09
Speaker 1: swimming in it. You know, any motion that I make,
8:12
Speaker 1: or any motion that any planet makes will sort of
8:14
Speaker 1: generate a little ripple in that Google. Yeah, precisely, And
8:18
Speaker 1: we are listening for those ripples, and we've been listening
8:20
Speaker 1: for them for a few decades and recently, just a
8:23
Speaker 1: few years ago, they actually detected these ripples. As an
8:26
Speaker 1: incredible story because people had thought these ripples existed for
8:29
Speaker 1: a long long time, but they thought it might be
8:31
Speaker 1: impossible to detect them because they are so small, because
8:35
Speaker 1: they're so faint, because gravity is so weirdly weak. And
8:39
Speaker 1: they had to build a really powerful device it's called
8:43
Speaker 1: a laser interferometer with two long arms on it that
8:47
Speaker 1: measures the length of these like kilometer long arms to
8:50
Speaker 1: see if they shrink a tiny bit like the width
8:53
Speaker 1: of a proton. So it's a really really difficult measurement
8:56
Speaker 1: to make because these gravitational waves are very very subtle, right,
9:00
Speaker 1: because you know, like if I shake my fist, I'm
9:02
Speaker 1: generating ways. But there's probably no way that anything that
9:04
Speaker 1: we have could possibly measure that. Right. Probably you need
9:08
Speaker 1: like these giant machines just to measure that the big
9:10
Speaker 1: ones coming from space, that's right. But you know, I
9:12
Speaker 1: thought for a long time even the big ones coming
9:14
Speaker 1: from space would be impossible. What I was a grad
9:17
Speaker 1: student thinking about what field of physics to work, and
9:20
Speaker 1: I considered going to cal Tech and working on the
9:22
Speaker 1: gravitational wave system. But I remember thinking, of these guys
9:25
Speaker 1: are never going to spot out, and they're gonna be
9:27
Speaker 1: working forever and never see it. And hey, I was wrong,
9:30
Speaker 1: and I'm glad they've been proven wrong. They found something
9:33
Speaker 1: amazing about the universe and won themselves a Nobel Prize along.
9:37
Speaker 1: So what you think is impossible today might be totally
9:40
Speaker 1: routine in twenty years. You never missed that on that rate?
9:44
Speaker 1: Did it? Didn't get to surf all the way to Sweden.
9:46
Speaker 1: You didn't catch the wave. Yea. And we could have
9:48
Speaker 1: met at cal Tech? Isn't that weird? Yeah, that's imagine
9:50
Speaker 1: an alternate reality where you did go working Lego and
9:52
Speaker 1: then we somehow met there. Yeah, but then we would
9:55
Speaker 1: have met in person, and we probably wouldn't have gotten along,
9:58
Speaker 1: probably wouldn't have started working to go there anyway. So
10:01
Speaker 1: there are gravitational waves all around you, but only really
10:04
Speaker 1: massive objects create gravitational waves that we can detect, right,
10:07
Speaker 1: And that's what we measure with Lego. We measure waves
10:10
Speaker 1: that are coming from space from really crazy events. And
10:13
Speaker 1: so I guess Henrick's question is can one of these
10:16
Speaker 1: waves kill you? Like, if you're standing there and a
10:19
Speaker 1: big wave comes through you, is it gonna affect you
10:22
Speaker 1: or could you even feel it? Because you know, if
10:24
Speaker 1: it's bending and stretching space, would in all my particles
10:27
Speaker 1: still still stay together? Yeah, in principle, these things do
10:30
Speaker 1: have an effect on you also, right, you do get
10:33
Speaker 1: bent and stretched when gravitational waves go through you, the
10:36
Speaker 1: ones that hit Earth they affect things that are a
10:38
Speaker 1: kilometer long by about the size of a proton, so
10:42
Speaker 1: the effect on you is totally negligible. You can't feel them.
10:46
Speaker 1: But these are black holes that are like one point
10:48
Speaker 1: three billion light years away, And one of the reasons
10:51
Speaker 1: why they're so faint is because the black holes are
10:54
Speaker 1: so far away. So it's reasonable to ask, like, if
10:57
Speaker 1: it was closer, if there was black holes colliding nearby,
11:00
Speaker 1: making big gravitational waves closer, what would be the effect
11:04
Speaker 1: on your body? And it's certainly true that it would
11:06
Speaker 1: pull and push you as well. Wow, yeah, because I
11:09
Speaker 1: guess like if you're really far away from an explosion
11:13
Speaker 1: or something, then you don't feel the effects very much
11:16
Speaker 1: because like you might feel a little bit of the
11:18
Speaker 1: wind or the air kind of hitting on you, but
11:20
Speaker 1: you wouldn't necessarily be hurt. But like, what if you're
11:24
Speaker 1: right next to the explosion, that would be bad news.
11:26
Speaker 1: Absolutely it would be bad news. And the closer you
11:28
Speaker 1: get to these things, the more powerful they are. The
11:30
Speaker 1: thing is, though, gravitational waves never really that powerful. Like
11:35
Speaker 1: take one of these events, these black holes that at
11:37
Speaker 1: one point three billion light years away, the wave is
11:40
Speaker 1: really really weak over here. It's one part in ten
11:43
Speaker 1: to the twenty one. So that means that if something
11:45
Speaker 1: is like ten to the twenty one long, then it
11:48
Speaker 1: shrinks by one. Now ten is predunculously big, right, which
11:54
Speaker 1: is why these things are so hard to see. So
11:56
Speaker 1: bring yourself closer, right, say you get, for example, just
11:58
Speaker 1: one light year away from these black holes, and just
12:01
Speaker 1: to paint a picture, lego measures like spinning black holes,
12:04
Speaker 1: like black holes that are collapsing into each other, and
12:07
Speaker 1: so they're it's like the death sworld of two black holes. Yeah,
12:10
Speaker 1: because to make gravitational waves, you can't just have static mass.
12:14
Speaker 1: That doesn't make a wave. You need stuff that's accelerating.
12:16
Speaker 1: And so these black holes that are swirling around each other,
12:19
Speaker 1: attracting each other, spinning in to their eventual collision, there
12:22
Speaker 1: are great opportunities to see gravitational waves because there's huge
12:25
Speaker 1: amounts of mass and there's a lot of acceleration because
12:28
Speaker 1: they're spinning around each other. So now we're talking about
12:30
Speaker 1: being one point three light years from two black holes gliding,
12:34
Speaker 1: and you're saying this is where it starts to get dangerous. Well,
12:36
Speaker 1: it doesn't actually get dangerous from the gravitational wave point
12:39
Speaker 1: of view because the power of that is like still
12:41
Speaker 1: one part intended the twelve, you know, so like if
12:45
Speaker 1: you brought the whole earth within a light year of
12:48
Speaker 1: these black holes, then the whole earth would shrink by
12:51
Speaker 1: like a hundreds of a millimeter, and one part in
12:54
Speaker 1: tend of the twelve is very small whole earth. So
12:57
Speaker 1: would that affect me? Like, it doesn't sound like it would,
13:00
Speaker 1: but I don't know, like maybe we'll scramble all of
13:02
Speaker 1: my atoms or something. No. One, one hundreds of a
13:05
Speaker 1: millimeter full of the whole earth is unmeasurably small just
13:08
Speaker 1: for you, right, so you wouldn't even notice it. It
13:10
Speaker 1: would be very difficult for you to notice. It could
13:13
Speaker 1: break up molecules or something at that level. Molecules, you know,
13:16
Speaker 1: because you're if you're stretching molecules. Molecules are pretty small.
13:19
Speaker 1: Molecules are pretty small, but they're pretty tough. You know.
13:21
Speaker 1: They're basically held together by these little bonds which are
13:23
Speaker 1: like springs. And so it's like if somebody came and
13:26
Speaker 1: tugged on you with a force, you know, enough to
13:29
Speaker 1: pull you by one dred of a millimeter, you would
13:33
Speaker 1: pretty much survive that, right, it's like it's a very
13:36
Speaker 1: gentle tug on the entire earth, right, so even just
13:40
Speaker 1: on you, it would be almost imperceptible. All right, So
13:44
Speaker 1: it's still pretty save with a light ear. What if
13:46
Speaker 1: I get closer, Yes, if you get within like you know,
13:48
Speaker 1: ten thousand kilometers of the center of this black hole,
13:51
Speaker 1: then we're talking about gravitational waves that are now serious.
13:54
Speaker 1: They're like one part in the thousand. Like I would
13:56
Speaker 1: shrink and contract by you know, a couple of millimeter,
14:00
Speaker 1: couple of millimeters. Yeah, and so again I think you
14:02
Speaker 1: would survive that. Like, really, you shrink and contract more
14:05
Speaker 1: than that every day just walking around. Your height changes
14:08
Speaker 1: more than a millimeter because of the compression on your
14:11
Speaker 1: spine from walking around. I don't know. Maybe you never
14:13
Speaker 1: get up from your chair so you don't drink as
14:15
Speaker 1: much as other people. But somethings I laid down in
14:17
Speaker 1: my chair and there's some stretching going on. Well that's
14:20
Speaker 1: good for your back and for your height. But you know,
14:22
Speaker 1: your height changes by a lot more than that just
14:24
Speaker 1: during the day. So I don't think I would have
14:26
Speaker 1: any effect on your health. But I see we're pretty
14:27
Speaker 1: squishy again, We're pretty squishy. But you know, say, for example,
14:31
Speaker 1: you're in a space suit, having your space suit get
14:33
Speaker 1: pulled by one part in a thousand, you know that
14:35
Speaker 1: could like crack the glass or break something important, or
14:39
Speaker 1: if you're in a space ship, you know, maybe the
14:41
Speaker 1: electronics are sensitive. So I wouldn't recommend. What about my bones?
14:45
Speaker 1: Could my bones take it? Yeah? Your bones could take it,
14:47
Speaker 1: for sure. I mean one part in a thousand is
14:49
Speaker 1: not very much your bones, even though they feel pretty tough,
14:52
Speaker 1: there's some spring to them. You're talking really close in
14:54
Speaker 1: thousand kilometers from the center of a black hole is
14:58
Speaker 1: like you're like right there, it's very us and you're
15:01
Speaker 1: not even going to survive getting that close, Like you're
15:04
Speaker 1: going to be torn apart by the gravitational forces that
15:07
Speaker 1: exist just from the black holes, well before the gravitational
15:11
Speaker 1: waves do anything to you. Really, Yeah, because remember near
15:15
Speaker 1: a black hole, the gravitational forces, just the static ones,
15:18
Speaker 1: not the changing ones, not the ripples in the gravitational field,
15:21
Speaker 1: just the field itself is really really strong. And the
15:24
Speaker 1: closer you are to the black hole, the stronger the forces.
15:27
Speaker 1: So if your toes are closer than your head, then
15:30
Speaker 1: there's a stronger force on your toes, and there is
15:32
Speaker 1: on your head, which is the same thing as the
15:34
Speaker 1: black hole pulling you apart. So if those forces that's
15:37
Speaker 1: called tidal forces, the force on your head and your
15:40
Speaker 1: toes is very different, then you get yanked apart. And
15:43
Speaker 1: you don't have to be very close to a black
15:45
Speaker 1: hole before those forces start to be larger than your
15:48
Speaker 1: body can take. So most likely the waves won't kill you.
15:53
Speaker 1: It will be something else. That's right. The shredded pieces
15:55
Speaker 1: of your body that survived that close to the black
15:58
Speaker 1: hole will not be damaged very much by the gravitational wave.
16:01
Speaker 1: You'll already be torn apart alright. So then I guess
16:05
Speaker 1: answer for Henrik is no, like a gravitation a wave
16:08
Speaker 1: can't really kill you because if if there's anything causing
16:12
Speaker 1: a gravitational wave that big, then it's probably gonna kill
16:15
Speaker 1: you in some other way. That's right, exactly. So if
16:19
Speaker 1: gravitational waves get big enough to do any damage, you're
16:22
Speaker 1: probably already dead. All right. Well, I feel a lot better.
16:26
Speaker 1: I was getting kind of concerned there. I was like,
16:28
Speaker 1: it's something else I have to worry about. No, just
16:32
Speaker 1: avoid black holes is good general advice. Stay at least
16:35
Speaker 1: ten thousand kilometers from them. If not more, somebody should
16:38
Speaker 1: put up signs or something caution universe singularity ahead. All right, well, Henry,
16:45
Speaker 1: I hope that answered your question, and I hope you
16:47
Speaker 1: can sleep a little better at night knowing that gravitational
16:51
Speaker 1: waves can't really kill you. Maybe those gravitational waves will
16:54
Speaker 1: be get rocking him to sleep, sleep to the sound
16:56
Speaker 1: of the universe. All right, Well, let's get into some
16:58
Speaker 1: of these other questions about the nature of matter and
17:01
Speaker 1: alternate stars. But first let's take a quick break. All right,
17:16
Speaker 1: we're back answering questions from listeners. Which are the best questions?
17:21
Speaker 1: And I have to say, Daniel, these questions we got
17:23
Speaker 1: today are pretty intense. I feel like usually people ask
17:27
Speaker 1: sort of like funny situations or you know, more basic things,
17:30
Speaker 1: but these are like intense, like can a gravitational wave
17:33
Speaker 1: kill you? And making me question the nature of matter? Well,
17:37
Speaker 1: we are living in strange times and everybody's at home
17:39
Speaker 1: thinking deep thoughts. I guess. All right, Well, the next
17:41
Speaker 1: question we have for today comes from one Ignacio Vadagas,
17:45
Speaker 1: and he didn't say where he's from, so we're just
17:47
Speaker 1: going to assume Jupiter. Maybe he emailed as um, you know,
17:52
Speaker 1: fourteen years ago and he only just got the email.
17:54
Speaker 1: All right, Well, here's what one wanted to know. I
17:57
Speaker 1: was just wondering whether we have any idea yes, as
18:00
Speaker 1: to why there is mutter, what causes energy to be
18:05
Speaker 1: sequestered in what we call particles? Well that is deep
18:08
Speaker 1: stuff that is deep, Like why are we here? He's
18:11
Speaker 1: basically asking. Yeah, there's a lot of possible angles to
18:14
Speaker 1: this question. I really wish I could chat with one
18:16
Speaker 1: and figure out, like what is he asking? Is he
18:18
Speaker 1: asking like why do we have matter or not just radiation?
18:21
Speaker 1: Or why is there matter or not antimatter? Or why
18:24
Speaker 1: is there something rather than nothing? Or why is energy
18:28
Speaker 1: sort of clumped together into particles? Or there's a lot
18:31
Speaker 1: of really fun angles. You want to ask him questions
18:34
Speaker 1: about his question. I want to make sure we're answering
18:37
Speaker 1: the like deep deep curiosity that's wormed its way into
18:40
Speaker 1: his brain. I want to make sure that we are
18:42
Speaker 1: We're going to touch on the question he really wants answered. Well,
18:45
Speaker 1: it's it sounds like a pretty interesting question. I guess
18:47
Speaker 1: he's asking, we have the universe and when we know
18:50
Speaker 1: about energy, but why do we have matter? Like why
18:53
Speaker 1: does matter exist in the universe, Like why the energy
18:57
Speaker 1: suddenly decide to, you know, form into little particles of matter. Yeah,
19:02
Speaker 1: that is a great question, and you know, the short
19:04
Speaker 1: answer is, we really just don't know. But how much
19:07
Speaker 1: we don't know sort of depends on what you think
19:10
Speaker 1: is the most basic element of the universe, you no,
19:18
Speaker 1: Like we have talked on this podcast before that sort
19:20
Speaker 1: of historically we discovered that things are made out of particles.
19:25
Speaker 1: You know, that all the stuff around you can be
19:27
Speaker 1: broken up into smaller pieces, and those pieces can be
19:30
Speaker 1: broken up into smaller pieces, and those can be broken
19:32
Speaker 1: up in the even smaller pieces, and it gives you
19:34
Speaker 1: the sense sort of that like particles are the basic
19:37
Speaker 1: unit of the universe, that everything is made out of particles, right,
19:41
Speaker 1: And the way particles interact is through these things called fields.
19:45
Speaker 1: So that's sort of historically the way our understanding the
19:48
Speaker 1: universe was developed. But more recently we have sort of
19:52
Speaker 1: a new view on what the basic element of the
19:55
Speaker 1: universe is, and that suggests that particles are not really
19:58
Speaker 1: the building block of the universe of matter itself, but
20:01
Speaker 1: that the deepest thing are actually the field. Wait, aren't
20:04
Speaker 1: they the same thing? Like isn't a particle like what
20:07
Speaker 1: they call an excitation of that field or like a
20:09
Speaker 1: blip in the field. Yeah, Well, this new view says
20:12
Speaker 1: exactly that that particles are just a weird state of
20:15
Speaker 1: a field. But that says that the fields are the
20:17
Speaker 1: deepest thing. You know. The particles aren't the fundamental building blocks.
20:21
Speaker 1: They're just like a configuration of the fields. It's like,
20:24
Speaker 1: you know, what's more fundamental, your hand or a fist.
20:27
Speaker 1: Your fist is just your arrangement of your fingers in
20:29
Speaker 1: a certain way, or like what's more fundamental a wave
20:33
Speaker 1: or the ocean? Yeah, precisely. And so the fields are
20:35
Speaker 1: the ocean, and the particles are the waves in that ocean.
20:39
Speaker 1: And so more modern view is that everything in the
20:42
Speaker 1: universe is filled with fields. We have an electromagnetic field,
20:45
Speaker 1: and the waves in that field are photons. We even
20:48
Speaker 1: have an electron field. It's different from the electromagnetic field.
20:52
Speaker 1: Waves in the electron field are electrons. And then every
20:56
Speaker 1: particle that we're familiar with has a field, and those
20:58
Speaker 1: particles are just wiggles in those fields, like little ripples,
21:02
Speaker 1: like a little echo or a little blip, yeah, like
21:05
Speaker 1: a little packet. And then it's a really interesting and
21:08
Speaker 1: fun question to ask, like, well, why do those fields
21:11
Speaker 1: have packets? Right? One of those fields just sort of
21:13
Speaker 1: slash around and have energy everywhere. I think this is
21:16
Speaker 1: sort of what he was asking, like why is energy
21:18
Speaker 1: clustered together into these little blip called part of where
21:21
Speaker 1: did those blips come from? Yeah? And why do we
21:24
Speaker 1: have blips and not just you know, blushes or squishes
21:26
Speaker 1: or squashes or whatever, because then we wouldn't be here
21:31
Speaker 1: to answer it's a question. Yeah, And so you know,
21:33
Speaker 1: the first the deepest answers, we really just don't know.
21:36
Speaker 1: But we have sort of two suggestions maybe sort of
21:40
Speaker 1: directions of thought or people sort of you know, groping
21:43
Speaker 1: in the dark towards ideas. And one is that these
21:46
Speaker 1: fields are not just fields, their quantum fields. These fields
21:51
Speaker 1: can't just have any particular value. They seem to have
21:54
Speaker 1: certain discrete set of states that they can take, you know,
21:58
Speaker 1: then go up one unit of energy or two two
22:00
Speaker 1: units of energy, but not one point three seven nine. Oh,
22:03
Speaker 1: I see, they like um. They're kind of fuzzy. You
22:05
Speaker 1: can move this field in like half of up wave. Yeah, exactly.
22:09
Speaker 1: And we associate these quantum units with particles. Like when
22:13
Speaker 1: the field gets one more unit of energy that that
22:16
Speaker 1: field can absorb, we consider that one more particle. And
22:19
Speaker 1: in quantum mechanics we actually do the math. We call
22:22
Speaker 1: these things counting operators. We like create new particles, destroyed particles.
22:26
Speaker 1: That's how you put energy into the field. So one
22:29
Speaker 1: way to think about it is that that a particle
22:31
Speaker 1: is just like a quantized unit of energy in the field.
22:35
Speaker 1: I guess maybe is it kind of like if you
22:36
Speaker 1: throw a whole bunch of water into the air, Like
22:39
Speaker 1: water tends to, you know, kind of clump into droplets,
22:42
Speaker 1: you know, it doesn't just kind of spread out when
22:44
Speaker 1: you throw it up into the air. Yeah, it certainly does.
22:47
Speaker 1: I'm not sure if that's because it's quantized or there's
22:50
Speaker 1: surface tension, or surface tension leads a quantization. That's actually
22:54
Speaker 1: really cool thought there probably is a connection there. But
22:56
Speaker 1: that's kind of the idea is that it tends to cluster,
22:58
Speaker 1: or it tends to like little bit tends to clump
23:01
Speaker 1: into little bits. And the second idea, which is connected
23:04
Speaker 1: is that we've noticed that there are some symmetries to
23:07
Speaker 1: these fields, Like these fields don't just do anything, you know,
23:11
Speaker 1: they have rules that they follow, like the field follows
23:13
Speaker 1: the same rules over here as they do in another
23:16
Speaker 1: part of the universe. Or if you spin yourself in
23:19
Speaker 1: the field, it follows the same rules as if you
23:22
Speaker 1: hadn't spun yourself. So they're these symmetries, translational and rotational
23:26
Speaker 1: symmetries to the fields themselves, right, And this is going
23:30
Speaker 1: to sound like a really weak and fuzzy argument, but
23:33
Speaker 1: essentially a particle is the simplest thing that can exist
23:37
Speaker 1: in those fields that satisfies those symmetries. Like that's how
23:41
Speaker 1: you explain why it forms into particles. Well, there's this
23:45
Speaker 1: feeling and quantum mechanics that sort of everything that can
23:48
Speaker 1: happen does happen. So if it's not explicitly forbidden by
23:52
Speaker 1: some rule, then you will see it happen eventually. And
23:55
Speaker 1: so particles are sort of like the simplest thing that
23:58
Speaker 1: can exist that isn't ruled out by some basic symmetry
24:03
Speaker 1: or conservation rule or whatever. So therefore they do exist.
24:07
Speaker 1: Now that's a pretty weak argument because there's lots of
24:11
Speaker 1: times that we expected something to exist, like a new
24:14
Speaker 1: particle or whatever, we don't see it exists, and so
24:16
Speaker 1: we say, well, therefore there must be some new rule
24:19
Speaker 1: that eliminates it, and we just add that rule to
24:21
Speaker 1: the list. So, you know, it's not like a lot
24:23
Speaker 1: of these rules have deep understanding them. Some of them do.
24:27
Speaker 1: Some of them come out of like really beautiful symmetries
24:29
Speaker 1: of nature, etcetera. But some of them seem a little
24:32
Speaker 1: ad hoc. So it's a totally valid open question sort
24:35
Speaker 1: of at the edge of physics and philosophy, like why
24:38
Speaker 1: do these particles exist? Why do we have any particles
24:41
Speaker 1: at all? Why do the conservation laws allow for these particles?
24:44
Speaker 1: Why not something else bigger and squishier. Maybe a way
24:46
Speaker 1: to interpret his question is like, could you have a
24:49
Speaker 1: universe without particles? Could the universe just kind of could
24:52
Speaker 1: there be a version of this universe where no particles
24:54
Speaker 1: ever formed and everything is just kind of like the
24:57
Speaker 1: fields are just totally on blipped where this fields are
25:00
Speaker 1: sitting there. You know, there are some other configurations of fields,
25:03
Speaker 1: but you know, those universes would not lead to people
25:06
Speaker 1: asking questions about those particles and those podcasts. So it's
25:11
Speaker 1: possible those universes could exist, but they wouldn't be as
25:14
Speaker 1: interesting or as rich, and so they wouldn't be in
25:16
Speaker 1: them asking this question. So this sort of this selection
25:19
Speaker 1: effect that we only tend to ask these questions in
25:22
Speaker 1: universes where there are interesting things happening. But we already
25:25
Speaker 1: we have ideas for like other ways you could arrange
25:28
Speaker 1: quantum fields that are not particles, these things called like squirmons,
25:33
Speaker 1: that are not the same kind of clusters of energy
25:35
Speaker 1: in the quantum fields, but in fact are these like
25:38
Speaker 1: we're not these other stable configurations of quantum fields that
25:41
Speaker 1: are not quite particles. They don't act the same way. Interesting.
25:46
Speaker 1: I guess maybe the answer you tell me is that
25:48
Speaker 1: you know, in quantum physics it's all kind of like statistical,
25:52
Speaker 1: and so if a field can kind of form into
25:55
Speaker 1: a particle, it probably will. It probably will. Yeah, particles
25:58
Speaker 1: will just spontaneously occur, and probably especially if you have
26:02
Speaker 1: like energy, right, if you like, if there's energy around,
26:05
Speaker 1: those particles are going to pop up. And that's where
26:07
Speaker 1: we come from. And I would say that like probably
26:09
Speaker 1: half of the theorists out there, the people who think
26:12
Speaker 1: really deeply about quantum theory thinking that way. They think
26:14
Speaker 1: the fields are the basic thing, and the particles are
26:17
Speaker 1: like manifestations of those fields. But you know, the other
26:20
Speaker 1: half of the community thinks about it the other way.
26:23
Speaker 1: They think, no, no, no, the basic thing in the
26:26
Speaker 1: universe are particles and fields. Those are just you know,
26:30
Speaker 1: virtual particles. So this is just how particles talk to
26:32
Speaker 1: each other. They think of the fields as you know,
26:36
Speaker 1: just like a huge swarm of very briefly living particles,
26:41
Speaker 1: because the particles are the things we interact with, right,
26:43
Speaker 1: The fields are a little bit more abstract. The particles
26:46
Speaker 1: are the things that we like, we can see, we
26:48
Speaker 1: can detect, we're made of them. So there's a bunch
26:51
Speaker 1: of people out there that think that particles are the
26:53
Speaker 1: basic element of the universe and not the fields. Like
26:55
Speaker 1: if you didn't have particles, you wouldn't have fields. Yeah, yeah, precisely.
26:59
Speaker 1: And and if you ask those people like well why
27:01
Speaker 1: are their particles, well, you know, they have no idea
27:03
Speaker 1: because they just start from the particles, just because that's
27:06
Speaker 1: the aw just because it's like asking the other half like, well,
27:09
Speaker 1: why are their fields? You're telling me particles are made
27:11
Speaker 1: of fields, great, why are their fields? Well, we don't know.
27:14
Speaker 1: You know, that's that's down to like why is there
27:17
Speaker 1: anything we just this is as deep as we've gotten
27:19
Speaker 1: so far, we don't know what the next layer of
27:22
Speaker 1: knowledge or ignorance is, so we're struggling to understand what
27:26
Speaker 1: it means. But you know, this is why we do it.
27:27
Speaker 1: We look for the patterns, We try to identify the
27:30
Speaker 1: weirdness in those patterns, and those lead to these questions
27:33
Speaker 1: which eventually, we hope in fifty two hundred years will
27:36
Speaker 1: lead to really deep insights about like why the universe
27:40
Speaker 1: exists at all. It's like the classic chicken fields and
27:43
Speaker 1: egg particles problem. You know, which came first? Which is
27:47
Speaker 1: more fundamental and or tas obviously the egg came first.
27:50
Speaker 1: I never understood that one egg led to the chicken.
27:55
Speaker 1: What do you mean who laid the egg? The pre
27:57
Speaker 1: chicken mom of the egg mutated chicken. It is a
28:00
Speaker 1: pretty chicken, a chicken, Daniel. Well, if it annihilis with
28:04
Speaker 1: an anti chicken, then and that's why this is not
28:07
Speaker 1: a biology podcast, right. Well, it sounds like the answer
28:11
Speaker 1: for Juan here is why not or stay tuned Like
28:16
Speaker 1: he's asking pretty basic questions of like why are things things? Yeah,
28:20
Speaker 1: we just don't know one and we're trying to figure
28:22
Speaker 1: it out. And these are the deepest funnest questions to
28:24
Speaker 1: think about, so don't give up, we'll figure it out.
28:27
Speaker 1: All right. Well, I guess one won't be sleeping better
28:30
Speaker 1: at night after that one. But we have one more question,
28:33
Speaker 1: and this one's about alternate stars, which I thought was
28:36
Speaker 1: pretty cool. But and so let's get into it. But
28:38
Speaker 1: first let's take a quick break. All right. We're answering
28:52
Speaker 1: questions from listeners today, and we've had two pretty good ones,
28:56
Speaker 1: and this last one kind of blew my mind a
28:58
Speaker 1: little bit. So some to hear has a question about
29:01
Speaker 1: whether or not as stars can be different. I really
29:05
Speaker 1: enjoyed a recent episode on turning Jupiter into a star
29:09
Speaker 1: and how what would it be involved with that? I
29:12
Speaker 1: was wondering, since you're talking primarily about fusion based stars,
29:18
Speaker 1: what would happen if you had a fission based star?
29:21
Speaker 1: Do they exist? Are they theoretically possible? What would they
29:25
Speaker 1: look like? All right? A pretty interesting question. I guess
29:28
Speaker 1: he's asking whether you can have a star that works
29:32
Speaker 1: based on fission and not fusion, or is he asking
29:35
Speaker 1: whether stars can be fizzy? What would it taste like
29:39
Speaker 1: to sip a star? How long a straw would you
29:41
Speaker 1: need to safely sip the star. It might be a
29:45
Speaker 1: little hot, better blowing there, use some gravitational waves to
29:48
Speaker 1: cool it off. Yeah, there you go, all right, But
29:51
Speaker 1: I guess the question is could you have a fissi
29:53
Speaker 1: and stand So maybe let's recap whether fission powered stars.
29:55
Speaker 1: So the reason that the Sun is a star, the
29:58
Speaker 1: reason it glows, the reason it is giving off energy
30:00
Speaker 1: is that doing something that releases energy, and that's fusion,
30:05
Speaker 1: and fusion is taking lighter elements like hydrogen or helium,
30:09
Speaker 1: things that have just like a couple of protons and
30:11
Speaker 1: sticking them together and when they stick together, a lot
30:14
Speaker 1: of energy is released. So that's called fusion. Join things together,
30:19
Speaker 1: and anything on the periodic table. It's like lighter than
30:22
Speaker 1: iron because of the way the protons and neutrons are
30:24
Speaker 1: stuck together in the vagaries of the strong force. When
30:27
Speaker 1: you join them together, you release energy, so it gives
30:31
Speaker 1: off energy. You can essentially combine this stuff, make bigger,
30:34
Speaker 1: heavier elements and make your star glow. And that's what
30:38
Speaker 1: powers all of the stars in the universe. And that's
30:41
Speaker 1: always been a little bit confusing that the idea that
30:43
Speaker 1: by joining things together it releases energy. Yeah, joining things
30:47
Speaker 1: together releases energy. It takes energy to pull them apart.
30:50
Speaker 1: Think about it like that. I see so like it's
30:53
Speaker 1: kind of like when you bring to magnets clothes together,
30:55
Speaker 1: they snap together and they make a sound. Yeah. Like
30:58
Speaker 1: that sound is almost kind of like the energy released
31:00
Speaker 1: in the center of a star. Yeah. And it's all
31:03
Speaker 1: about the configuration of these protons and neutrons together. And
31:06
Speaker 1: it's a bit counterintuitive because it's all the same particles, right,
31:09
Speaker 1: There's just protons and neutrons, and either they're attracting or
31:12
Speaker 1: they're repelling. And remember that all the protons, they're repelling
31:15
Speaker 1: each other. The whole reason the nucleus holds together is
31:18
Speaker 1: because of the strong force. The strong force sends these
31:22
Speaker 1: gluons back and forth between the neutrons and the protons
31:24
Speaker 1: and really ties the thing together. The fact that the
31:27
Speaker 1: protons are positively charged and pushing away from each other
31:30
Speaker 1: is really not even relevant anymore because the strong force
31:33
Speaker 1: is so powerful. And it's also really hard to do calculations,
31:37
Speaker 1: like it's not a simple thing to figure out what
31:40
Speaker 1: some arrangement of protons and neutrons will feel like. But
31:43
Speaker 1: we do know that for elements lighter than iron, when
31:47
Speaker 1: you stick them together you get energy, and that's fusion, right,
31:51
Speaker 1: So that that's most stars that we know. At least
31:53
Speaker 1: our star works on fusion. It's fusing hydrogen and helium.
31:58
Speaker 1: It's joining things to create that energy to power the
32:01
Speaker 1: star and also to make the heavier elements. Right, fusion
32:05
Speaker 1: needs light elements. You need stuff that's lighter than iron.
32:08
Speaker 1: And in the Big Bang we got mostly hydrogen, tiny
32:11
Speaker 1: little bit of helium and lithium, etcetera. But most of
32:13
Speaker 1: the heavier stuff in the universe was made by fusion.
32:16
Speaker 1: That's how you do it. Right. All of our atoms
32:19
Speaker 1: all in in our bodies, we were all made at
32:21
Speaker 1: the center of stars. That's right. All the uranium and
32:24
Speaker 1: all the iron and all the heavy stuff in the
32:26
Speaker 1: universe was made in these stars. That's how you do it.
32:29
Speaker 1: So all the stars that are out there, they're fusing
32:31
Speaker 1: and making this stuff, making particles. But where does the
32:34
Speaker 1: particles come from, Daniel, They come from the banana universe.
32:38
Speaker 1: They slipped in through a worm, all right. So that's
32:42
Speaker 1: one way to make energy fusion fusing things together. But
32:44
Speaker 1: you can also make energy by splitting atoms apart. That's
32:48
Speaker 1: called fission. That's right. If you have stuff that's really heavy,
32:51
Speaker 1: heavier than iron, then you get energy by doing the opposite,
32:55
Speaker 1: by breaking stuff apart. Like uranium is really heavy, much
32:59
Speaker 1: heavier than iron, has more protons in the nucleus, and
33:02
Speaker 1: when it splits open, it releases energy. So it's the opposite.
33:06
Speaker 1: Above iron, you get energy, when you split below iron,
33:10
Speaker 1: you get energy when you fuse. Right, there's like energy
33:13
Speaker 1: stored in that. It was somehow these elements came together
33:16
Speaker 1: and they're storing energy. They have energy inside of them,
33:19
Speaker 1: stored in their bonds, and then when you break them apart,
33:21
Speaker 1: that energy flies off. Yeah, if you like mechanical analogies,
33:25
Speaker 1: you can think of it like they're tied together and
33:27
Speaker 1: the springs are compressed, and when you cut the string,
33:30
Speaker 1: they fly apart and all that energy is then released.
33:33
Speaker 1: So you're releasing all that energy. And so this is
33:35
Speaker 1: another way to generate energy, and we do this in
33:38
Speaker 1: nuclear power plants. You find heavy uranium in the crust
33:41
Speaker 1: of the earth and you let it decay and you
33:43
Speaker 1: gather that energy. That's fission, right, Yeah, that's what all
33:46
Speaker 1: of our nuclear reactors use, is fission, that's right. We
33:49
Speaker 1: have not been able to make fusion work on Earth
33:51
Speaker 1: in a sustainable way with a few brief spits and
33:53
Speaker 1: spats of it here and there. We don't have like
33:56
Speaker 1: a fusion reactor yet. I mean, people are working on it.
33:58
Speaker 1: It's an awesome brodjet And if we could would be
34:01
Speaker 1: said in terms of energy, right, absolutely, because fusion doesn't
34:04
Speaker 1: create dangerous byproducts. You know, it works with very light
34:07
Speaker 1: elements and creates very light elements, and it's much more efficient.
34:11
Speaker 1: The fuel source for it would basically be hydrogen, which
34:13
Speaker 1: we can get a lot of in the ocean, So
34:16
Speaker 1: fusion would be pretty awesome, right. You don't need uranium
34:18
Speaker 1: or any of these radioactive elements. All right, So then
34:21
Speaker 1: the question is, can you have a star that works
34:24
Speaker 1: using fission? Like could you have a star where things
34:27
Speaker 1: at its center are being broken apart instead of fuse together? Yeah,
34:30
Speaker 1: And it's a great question, and it's exactly the kind
34:33
Speaker 1: of question of physicists would ask, you know, like, well,
34:36
Speaker 1: if you can do it this way, can you do
34:37
Speaker 1: it the other way? You know, you have two ways
34:39
Speaker 1: to make energy. Could you use either of them to
34:41
Speaker 1: power a star? It's a really great question. But the
34:44
Speaker 1: first part of his question was like do they exist? Like,
34:46
Speaker 1: are there stars out there that are fission ng and
34:50
Speaker 1: that's why they are burning? Right? So do they exist?
34:54
Speaker 1: Are there stars that work from using fission? We do
34:57
Speaker 1: not think so. We think that every single star out
35:00
Speaker 1: there in the night sky is fusing. And the reason
35:02
Speaker 1: it's pretty simple is that the universe is almost all hydrogen.
35:06
Speaker 1: In the Big Bang, the universe was made, and it
35:08
Speaker 1: was almost all hydrogen after a few hundred thousand years,
35:11
Speaker 1: and a little bit of helium was made during the
35:13
Speaker 1: Big Bang, but basically it's all hydrogen, and so that's
35:16
Speaker 1: the only fuel that's out there. You've got a universe
35:18
Speaker 1: filled with fuel for fusion and very very tiny amounts
35:23
Speaker 1: of the fuel you would need for fission, right, And
35:26
Speaker 1: the only way to make them is through those other stars,
35:28
Speaker 1: not even like the dimmer stars like the red dwarfs
35:31
Speaker 1: or something, even the brown dwarfs like those are fusing. Yeah,
35:34
Speaker 1: those are fusing special kinds of fusion. Sometimes you have
35:37
Speaker 1: deuterium in their or tritium or whatever. But it's all fusion.
35:40
Speaker 1: And that's just because the fuel in the universe is
35:42
Speaker 1: the fuel unique for fusion, not for fission. I mean,
35:45
Speaker 1: if we had a different universe where the Big Bang
35:47
Speaker 1: mostly made uranium and plutonium. Then yeah, you might have
35:51
Speaker 1: like vision based objects out there, but those heavy elements
35:54
Speaker 1: are very very rare. In fact, like we're sitting on
35:58
Speaker 1: top of a pretty rare clumb of stuff. You know.
36:01
Speaker 1: The Earth is mostly iron and nickel and really heavy
36:05
Speaker 1: stuff that's pretty rare in the universe, like by mass. Yeah,
36:09
Speaker 1: and that's what's kind of keeping the Earth hot at
36:12
Speaker 1: its center. Yeah, part of it is gravitational pressure, but
36:14
Speaker 1: another big part of it is the fact that we
36:16
Speaker 1: have radioactive heavy stuff in the center of the Earth
36:19
Speaker 1: that's decaying and it's emitting energy. And so in some
36:22
Speaker 1: sense you can sort of think of the Earth is
36:24
Speaker 1: like kind of a fission powered star because it's a
36:28
Speaker 1: really dense blob of stuff that's being kept molten by
36:32
Speaker 1: the energy from fission. Earth is pretty heavy metal. Yeah,
36:38
Speaker 1: if you'd like to think about it, you can imagine
36:39
Speaker 1: that we're sort of living in the atmosphere of a
36:42
Speaker 1: fission powered star. Yeah. Cool, But the Earth is not
36:46
Speaker 1: called a star. I guess it has kind of a
36:48
Speaker 1: fission engine and its core inside, but you wouldn't call
36:51
Speaker 1: it a star. You wouldn't call it a star because
36:53
Speaker 1: it's not glowing where the Earth doesn't give off light,
36:56
Speaker 1: and I think to be called a star even like
36:58
Speaker 1: in the infrared, well the Earth does in the infrared,
37:00
Speaker 1: like everything does. You're right, everything in the universe glows
37:03
Speaker 1: at some temperature, but it doesn't glow in the visible.
37:06
Speaker 1: It doesn't glow in the in the X ray. And
37:08
Speaker 1: so I think to be a star you really need
37:10
Speaker 1: to be like glowing and burning consuming the fuel. We
37:13
Speaker 1: don't sparkle. We don't sparkle exactly. You can imagine trying
37:16
Speaker 1: to do that, like you know, play sort of a
37:18
Speaker 1: play god and say, are right, I'm gonna take a
37:20
Speaker 1: huge amount of fission fuel like uranium, make it into
37:23
Speaker 1: a gas and just like drop it somewhere in deep
37:26
Speaker 1: space and think about like what would happen? Then, I
37:29
Speaker 1: think that's what Mike is asking. Is it theoretically possible
37:32
Speaker 1: to have a star that works from fission? So this
37:35
Speaker 1: is this is what you are experimenting with here, Like
37:38
Speaker 1: like how would you even make one? If it's possible
37:40
Speaker 1: at all? If you could get enough uranium. We we're
37:42
Speaker 1: talking about like an enormous amount of uranium, make it
37:45
Speaker 1: into a gas and drop it in space. Well, gravity
37:48
Speaker 1: would do its thing, just like it did for the
37:50
Speaker 1: formation of the Sun. It would gather all that stuff
37:52
Speaker 1: together and pull all those uranium nuclei, all those atoms together,
37:56
Speaker 1: eventually get them close enough so that when they decay,
37:59
Speaker 1: they knock into each other and create chain reactions and
38:02
Speaker 1: you would get real fission. You would get you know,
38:04
Speaker 1: in effect, burning and empowering this thing through fission, because
38:08
Speaker 1: I guess that's how nuclear bombs work, right, Like, if
38:13
Speaker 1: you put enough unstable uranium together at some point, it's
38:16
Speaker 1: gonna cause a chain reaction which will explode. Yeah, And
38:20
Speaker 1: that's how the sun works, just with fusion. That it's
38:22
Speaker 1: the energy from fusion is providing the energy needed to
38:26
Speaker 1: create fusion. That's called ignition, right, And so if the
38:30
Speaker 1: release of energy then enables the next release of energy,
38:33
Speaker 1: then you have someone which is self sustaining. And oh really,
38:36
Speaker 1: you know our son. I thought, like what causes things
38:39
Speaker 1: to fuse was the gravitational pressure. But it's also you mean,
38:42
Speaker 1: like the energy pressure from the other explosions. It's a balance, right.
38:46
Speaker 1: The reason the Sun is not exploding is because of gravity,
38:49
Speaker 1: and the reason it's not collapsing is because of the
38:51
Speaker 1: energy pressure, and so in our theoretical uranium star something
38:55
Speaker 1: similar would happen. Eventually, like gravity would pull this stuff together,
38:59
Speaker 1: which would increase use the rate of which stuff is
39:01
Speaker 1: decaying because you know, the decay products are not bouncing
39:03
Speaker 1: into each other more often. But eventually the energy being
39:07
Speaker 1: released from fission would balance out the gravity. You get
39:10
Speaker 1: some like interesting you know, balance there. And I don't
39:13
Speaker 1: think it would be as dense as our sun. Vision
39:16
Speaker 1: is not as powerful as fusion, but just release as
39:19
Speaker 1: much energy. I'm not sure exactly what it would look like,
39:22
Speaker 1: but theoretically that kind of thing is possible. You just
39:25
Speaker 1: have to get enough uranium and compress it. Yeah, the
39:29
Speaker 1: recipe is get a galaxy is worth uranium galaxies isolated
39:34
Speaker 1: in space and then wait a few million years and
39:37
Speaker 1: the gravity will bring it together and then they'll will ignite.
39:40
Speaker 1: And I'm not sure exactly what it would look like like,
39:42
Speaker 1: how dense it would get, and whether it would be
39:45
Speaker 1: hot enough to get the surface to be like a
39:47
Speaker 1: glowing plasma, or whether like other things would take over
39:50
Speaker 1: before you even got there. But I think theoretically, you know,
39:53
Speaker 1: it might be possible. Wudn't it be unstable like a
39:56
Speaker 1: nuclear ball like wouldn't in the chain reaction would run
39:58
Speaker 1: away and which is explode, right, but you have that
40:01
Speaker 1: pressure would keep blowing it out, which would lower the density.
40:04
Speaker 1: The same thing happens in the sun. Right. It's sort
40:06
Speaker 1: of like self regulates because the hotter it gets, the
40:08
Speaker 1: more it's pushing out, the less dens it gets, and
40:11
Speaker 1: that lowers the rate of the reaction. All right, So
40:14
Speaker 1: it sounds like the answer for Mike is that, yes,
40:18
Speaker 1: fission stars are possible, but not likely to exist because
40:24
Speaker 1: they are pretty difficult to make work. That's right, because
40:28
Speaker 1: the fuel just isn't out there, we think, and we're
40:31
Speaker 1: also not exactly sure what they would look like, and
40:33
Speaker 1: take a pretty sophisticated simulation to get like a realistic
40:36
Speaker 1: answer for what that star would look like. But theoretically
40:39
Speaker 1: the process is very similar to fusions. You just need
40:42
Speaker 1: the right fuel and the right conditions. And in the
40:45
Speaker 1: meantime we are sort of kind of sitting in a
40:46
Speaker 1: fish and star, right, which is the Earth, that's right.
40:50
Speaker 1: Fishing is warming your feet, all right? Cool? I think
40:54
Speaker 1: Mike can sleep will at night? Are you been having
40:55
Speaker 1: trouble sleeping? Jorge? I feel like all these questions are
40:58
Speaker 1: now related to like a well being. I'm just fetting
41:02
Speaker 1: a lot of empathy for these curious people. Well, curiosity
41:05
Speaker 1: does keep me up at night, but what lets me
41:08
Speaker 1: go to sleep is knowing that we just need to
41:09
Speaker 1: think about it and work on it, and eventually we
41:11
Speaker 1: will get these answers. The history of science is filled
41:14
Speaker 1: with people wondering about basic stuff that a hundred or
41:17
Speaker 1: two hundred years later even school children know the answer to.
41:21
Speaker 1: So eventually our deepest fundamental questions will be you know,
41:24
Speaker 1: like in story books in the year three thousand and
41:27
Speaker 1: we talked to preschools. All right, Well, thank you to
41:31
Speaker 1: Henry Kwan and Michael for sending in their questions, and
41:34
Speaker 1: thanks to everyone who sent their questions. And it's always
41:36
Speaker 1: kind of amazing and cool to think about all those
41:39
Speaker 1: people out there thinking about the universe and coming up
41:42
Speaker 1: with their questions and even more exciting stumping Daniel. So
41:46
Speaker 1: thank you everybody for trusting us with your questions, for
41:49
Speaker 1: taking the time to write in, giving us feedback on
41:51
Speaker 1: the show, and letting us know what you'd like to
41:54
Speaker 1: know more about. We want to hear from you, so
41:56
Speaker 1: please write to us at Questions at Daniel and Jorge
41:59
Speaker 1: dot com. And thanks to everyone also who has been
42:02
Speaker 1: leaving us ratings and comments and telling all their friends
42:06
Speaker 1: about this podcast. We really appreciate it well. Thanks for
42:08
Speaker 1: joining us, See you next time. Thanks for listening, and
42:19
Speaker 1: remember that Daniel and Jorge Explain the Universe is a
42:22
Speaker 1: production of I Heart Radio. For more podcast for my
42:25
Speaker 1: heart Radio, visit the i heart Radio app, Apple Podcasts,
42:29
Speaker 1: or wherever you listen to your favorite shows.