Latest / Daniel and Kelly’s Extraordinary Universe / Listener Questions 42: Life, the Universe and Ghosts!

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Listener Questions 42: Life, the Universe and Ghosts! · Daniel and Kelly’s Extraordinary Universe

• 0:08
  Speaker 1: Hey, Daniel, do you believe in ghosts?
• 0:11
  Speaker 2: You know, I do. Always say that there's plenty we
• 0:14
  Speaker 2: don't understand about the universe.
• 0:17
  Speaker 1: What does that mean that it's supernatural?
• 0:19
  Speaker 2: Well, you know, if we can describe it with physics,
• 0:22
  Speaker 2: then it's just part of nature. It's just natural.
• 0:25
  Speaker 1: What could there be physics that exists out there but
• 0:27
  Speaker 1: that we can't describe?
• 0:28
  Speaker 2: Hmmm, like some kind of superphysics.
• 0:31
  Speaker 1: Yeah, does that make you a superphysicist?
• 0:33
  Speaker 2: I'd gladly take a promotion to a super physicist with
• 0:36
  Speaker 2: a super salary.
• 0:37
  Speaker 1: Wait, would that mean that you sort of take off
• 0:39
  Speaker 1: your glasses and open up your shirt and you're actually
• 0:41
  Speaker 1: a superhero.
• 0:42
  Speaker 2: Super Daniel doing superphysics sounds super awesome.
• 1:01
  Speaker 1: Hi'm Hora mccartoonist and the author of Oliver's Great Big Universe.
• 1:05
  Speaker 2: Hi. I'm Daniel. I'm a particle physicist and a professor
• 1:08
  Speaker 2: at UC Irvine. But I'm not doing it for the money.
• 1:11
  Speaker 1: Wait what but you aren't getting paid though to be
• 1:13
  Speaker 1: a physicist, right?
• 1:14
  Speaker 2: Well, I mean I'm not like turning down the checks
• 1:16
  Speaker 2: out of principle or something crazy.
• 1:18
  Speaker 1: So you are doing it for money, just not for
• 1:21
  Speaker 1: the money.
• 1:23
  Speaker 2: I am getting paid do not worry. But all of
• 1:26
  Speaker 2: my students who graduate with physics PhDs and go off
• 1:29
  Speaker 2: to work for Google and their competitors are getting paid
• 1:32
  Speaker 2: a lot more than I am.
• 1:34
  Speaker 1: But you're still getting a pretty super salary, right though, Right,
• 1:37
  Speaker 1: I mean, I know what you see professors make. It's
• 1:40
  Speaker 1: pretty super money. And it's just not the money. It's
• 1:43
  Speaker 1: more of a generic money.
• 1:44
  Speaker 2: Yeah, it's more like a money than the money. But
• 1:47
  Speaker 2: you're right. I've got no complaints. I got a pretty
• 1:49
  Speaker 2: sweet gig over here, a super gig apparently.
• 1:52
  Speaker 1: But anyways, Welcome to our podcast, Daniel and Jorge Explain
• 1:54
  Speaker 1: the Universe, a production of iHeartRadio in.
• 1:56
  Speaker 2: Which we cash in on our passion and your paswer
• 2:00
  Speaker 2: for understanding the universe. We hope that the whole universe
• 2:03
  Speaker 2: can be described in terms of crazy mathematical models that
• 2:07
  Speaker 2: predict everything that could happen in this universe, and our
• 2:10
  Speaker 2: job on the podcast is to take those mysterious mathematical
• 2:14
  Speaker 2: models and explain all of them to you.
• 2:16
  Speaker 1: Yes, because it is a pretty mysterious and eerie universe
• 2:19
  Speaker 1: that sometimes seems supernatural, but that somehow a science has
• 2:23
  Speaker 1: been able to describe so far with models and data
• 2:26
  Speaker 1: and experiments.
• 2:27
  Speaker 2: Yeah, and it's a fascinating transition where originally we just
• 2:30
  Speaker 2: have sort of like mythological stories to describe the things
• 2:33
  Speaker 2: that we see, you know, like lightning and weather, and
• 2:36
  Speaker 2: later on we find explanations for those things. We can
• 2:39
  Speaker 2: make sense of them in sort of mechanistic or even
• 2:42
  Speaker 2: random quantum mechanical processes that describe them to show us
• 2:46
  Speaker 2: that they're following rules and laws and not just like
• 2:48
  Speaker 2: the whims of deities. But there's plenty of other stuff
• 2:51
  Speaker 2: out there in the universe we haven't yet explained, and
• 2:54
  Speaker 2: so one can wonder will science ever explain them or not?
• 2:58
  Speaker 1: Wait, are you saying that things like dark matter and
• 3:00
  Speaker 1: dark energy or our modern mythology, is there a god
• 3:04
  Speaker 1: of dark matter or god?
• 3:06
  Speaker 2: Is I really hope that there's physics of dark matter
• 3:08
  Speaker 2: instead of gods and goddesses of dark matter, because that
• 3:11
  Speaker 2: would be pretty hard to understand. But so far we
• 3:14
  Speaker 2: don't have an explanation for these things, right, and so
• 3:17
  Speaker 2: we just have to like hope that science will one
• 3:19
  Speaker 2: day figure it out, because we're projecting from all those
• 3:22
  Speaker 2: times that science has figured things out. But you know,
• 3:25
  Speaker 2: that's not exactly a guarantee that doesn't mean that science
• 3:28
  Speaker 2: will always figure things out philosophically. We don't have a
• 3:31
  Speaker 2: promise that the universe can always be described by our
• 3:35
  Speaker 2: mathematical stories.
• 3:37
  Speaker 1: I guess there's a fine line between mythology and methodology.
• 3:41
  Speaker 2: I don't know. I think this is a pretty bright
• 3:43
  Speaker 2: line between those two things, even though they do sound
• 3:46
  Speaker 2: very similar.
• 3:47
  Speaker 1: What if you do mythology very methodologically, very carefully.
• 3:51
  Speaker 2: I don't know. That sounds like doing astronomy very astrologically.
• 3:54
  Speaker 2: It sounds similar, but it's not really the same thing.
• 3:57
  Speaker 1: Well, maybe you make more money if you were an astrologer.
• 4:00
  Speaker 2: Oh almost absolutely, that's true.
• 4:02
  Speaker 1: I hear. They have good benefits.
• 4:04
  Speaker 2: They just don't have big telescopes. It's the problem.
• 4:07
  Speaker 1: But anyways, it is a pretty interesting and mysterious universe,
• 4:10
  Speaker 1: and we still have a lot of questions about it.
• 4:12
  Speaker 1: It's not just physicists and scientists who ask these questions
• 4:15
  Speaker 1: about how things are and why things are the way
• 4:18
  Speaker 1: they are, but it's also every day people going about
• 4:21
  Speaker 1: their everyday lives asking all the big questions.
• 4:24
  Speaker 2: That's right. It's not just the job of scientists to
• 4:27
  Speaker 2: figure out how the universe works. To think about the
• 4:29
  Speaker 2: ways that science can describe tiny little crawling creatures and
• 4:33
  Speaker 2: swarming quantum particles or huge swirling black holes. It's the
• 4:37
  Speaker 2: job of everybody out there to think about how this works,
• 4:40
  Speaker 2: to apply our human curiosity to the greatest puzzle of
• 4:44
  Speaker 2: all time.
• 4:44
  Speaker 1: Wait, did you have to get paid for something to
• 4:46
  Speaker 1: count as a job? My son makes that distinction all
• 4:49
  Speaker 1: the time. I like, it's your job to take out
• 4:52
  Speaker 1: the dishes from the dishwasher, he said, Well, technically, am
• 4:55
  Speaker 1: I getting paid?
• 4:56
  Speaker 2: M I think of it more like our role. You know,
• 4:59
  Speaker 2: some of us do get paid because it's our livelihood.
• 5:01
  Speaker 2: But for everybody else, your job is to support the
• 5:04
  Speaker 2: larger endeavor of science just by being curious, just by
• 5:07
  Speaker 2: wondering how things work and wanting to know the answer.
• 5:11
  Speaker 2: You know, the institution of science is quite literally powered
• 5:14
  Speaker 2: by your curiosity. Because you're a curious person and you
• 5:18
  Speaker 2: think this is a good idea, you elect politicians who
• 5:21
  Speaker 2: vote to use your taxes to support the institution of science.
• 5:25
  Speaker 1: That's right, it's your curiosity and also your taxes, some
• 5:29
  Speaker 1: of your taxes, or a very small fraction of your taxes.
• 5:32
  Speaker 2: Unfortunately, that's right, your taxes and our facts. Is I suppose.
• 5:37
  Speaker 1: It's taxtual and factual, and they're vote right, Like how
• 5:40
  Speaker 1: you vote makes a big difference about how what society
• 5:43
  Speaker 1: prioritizes and what kind of science and if science gets funded.
• 5:47
  Speaker 2: Yeah, that's exactly right, Which is one reason why this
• 5:50
  Speaker 2: podcast's mission is to fan the flames of curiosity, to
• 5:53
  Speaker 2: share our personal joy and wonder the incredible nature of
• 5:57
  Speaker 2: the universe and this incredible mystery we all share of
• 6:02
  Speaker 2: figuring it all out. Yep.
• 6:03
  Speaker 1: And people are curious and they have questions, and sometimes
• 6:06
  Speaker 1: on this podcast we like to answer those questions.
• 6:09
  Speaker 2: We do love to answer your questions. This is not
• 6:12
  Speaker 2: just a one way medium where you're listening to us talk.
• 6:14
  Speaker 2: We want to hear from you. We say it all
• 6:17
  Speaker 2: the time on the podcast, but we mean it. Please
• 6:19
  Speaker 2: write to us with your questions to questions at Danielandjorge
• 6:23
  Speaker 2: dot com. We answer all of them because we think
• 6:26
  Speaker 2: it's important that you have somebody to ask questions of,
• 6:29
  Speaker 2: somebody you can talk to about your curiosity about the universe.
• 6:33
  Speaker 1: So to the on the podcast will be tackling listener
• 6:41
  Speaker 1: questions number forty two, the Answer to life, Liberty and
• 6:44
  Speaker 1: the pursuit of happiness, Right.
• 6:46
  Speaker 2: Life, the universe and everything, including maybe the Supernatural.
• 6:50
  Speaker 1: Whoa a teaser spoiler alert.
• 6:53
  Speaker 2: I'm just trying to cash in on all those podcasts
• 6:55
  Speaker 2: that are higher ranked than us and just deal with
• 6:57
  Speaker 2: like Sasquatch, Bigfoot, and like ancient aliens.
• 7:00
  Speaker 1: Oh, why haven't we done that the science of Sasquatch.
• 7:04
  Speaker 2: That would be a very short episode or.
• 7:06
  Speaker 1: Is that more of an episode because's biology.
• 7:09
  Speaker 2: Yeah, maybe that's a good idea.
• 7:11
  Speaker 1: But we have some amazing questions here today about the Supernatural,
• 7:15
  Speaker 1: about neutrinos and neutron stars, and also about how to
• 7:19
  Speaker 1: make space. This is also life Organization podcast premit, like
• 7:25
  Speaker 1: how to get yourself organized.
• 7:26
  Speaker 2: That's right, you can make space in your house by
• 7:28
  Speaker 2: using neutrino beams that also capture ghosts. We're going to
• 7:32
  Speaker 2: tie it all.
• 7:32
  Speaker 1: Together so you only do experiments that really bring you joy.
• 7:36
  Speaker 1: Doesn't bring joy than you get them out of the left.
• 7:38
  Speaker 2: Oh man, we do a lot less science in that case.
• 7:41
  Speaker 1: So let's jump right in. And so a first question
• 7:43
  Speaker 1: comes from Brendan.
• 7:44
  Speaker 3: We've all heard stories about ghosts, telekinesis, remote viewing and
• 7:48
  Speaker 3: things like that, and I was wondering if we can
• 7:51
  Speaker 3: just assume that those are real for a second. How
• 7:53
  Speaker 3: could they work? I think it'd be really awesome to
• 7:56
  Speaker 3: hear your opinions.
• 7:57
  Speaker 1: Thank you. Interesting question. Brandon seems to be asking, like,
• 8:00
  Speaker 1: if all these stories about ghosts and esp and being
• 8:05
  Speaker 1: able to move things with your mind, if they were real,
• 8:07
  Speaker 1: how would they work from a physics perspective?
• 8:10
  Speaker 2: Yeah? I love this question because he's not like doubting
• 8:14
  Speaker 2: these observations. He's doing the science of it. He's like,
• 8:17
  Speaker 2: all right, let's see if we can construct an explanation,
• 8:21
  Speaker 2: not some metaphysical supernatural story that violates physics, but let's
• 8:26
  Speaker 2: see if we can bring it into the fold of science. Right,
• 8:29
  Speaker 2: Let's see, let's see if we can come up with
• 8:31
  Speaker 2: a way to explain this stuff without breaking physics.
• 8:34
  Speaker 1: Yeah, like, if maybe you do see a go someday
• 8:36
  Speaker 1: it could it be that you're crazy? Or is there
• 8:38
  Speaker 1: an actual explanation that someone could come up with.
• 8:42
  Speaker 2: That's right and usual disclaimer we are not offering psychological
• 8:45
  Speaker 2: advice on this podcast. Do not follow our health advice
• 8:48
  Speaker 2: in any.
• 8:48
  Speaker 1: Regards, or financial or career advice apparently, or legal or
• 8:53
  Speaker 1: any kind of advice. I guess we're just talking science here,
• 8:58
  Speaker 1: But yeah, let's maybe start with some of the situations
• 9:01
  Speaker 1: that he mentioned, for example, remote viewing, like if you
• 9:04
  Speaker 1: could see into the future maybe, or you can see
• 9:07
  Speaker 1: what's happening on the other side of the world with
• 9:09
  Speaker 1: your mind, how would that maybe work.
• 9:11
  Speaker 2: Yeah, this one is pretty awesome. I mean remote viewing.
• 9:14
  Speaker 2: I had to look this up to see exactly what
• 9:15
  Speaker 2: it meant. And it's the practice of seeking impressions about
• 9:19
  Speaker 2: a distant or unseen subject. So imagine, for example, you're
• 9:23
  Speaker 2: in your house in California and you want to know,
• 9:26
  Speaker 2: like what's going on in the oval office right now,
• 9:29
  Speaker 2: You like close your eyes and you concentrate and you
• 9:31
  Speaker 2: get a vision for what's happening there. Or you want
• 9:34
  Speaker 2: to know, like what's happening on the surface of the moon,
• 9:37
  Speaker 2: for example. So remote viewing would allow you to see
• 9:40
  Speaker 2: something really far away.
• 9:42
  Speaker 1: Like FaceTime without the iPhone exactly.
• 9:44
  Speaker 2: And something that's really fascinating about this one idea is
• 9:47
  Speaker 2: that it's pre technology, right. People have had this idea
• 9:51
  Speaker 2: of remote viewing for thousands of years, but now because
• 9:54
  Speaker 2: of technology, it's not really even that special. Like, as
• 9:58
  Speaker 2: you say, everybody has a device their pocket that you
• 10:00
  Speaker 2: could use to see what's going on on the other
• 10:02
  Speaker 2: side of the world. It's not really that complicated. We
• 10:05
  Speaker 2: have used physics to basically create this ability for almost everybody.
• 10:10
  Speaker 1: Well, do you think Brendan meant like, right, you can
• 10:12
  Speaker 1: see things happening right now somewhere else or maybe in
• 10:15
  Speaker 1: the past, or maybe in the future.
• 10:17
  Speaker 2: I think Brendan is probably talking about without iPhones, like
• 10:21
  Speaker 2: just using your mind. Somehow you can gather this information
• 10:24
  Speaker 2: using something other than the Internet. I think probably that's
• 10:27
  Speaker 2: what Brendan is imagining, not just facetiming your grandma.
• 10:30
  Speaker 1: Hmm, Well, I guess you can always use letters, but
• 10:33
  Speaker 1: they still.
• 10:33
  Speaker 2: Have mail, right, they do still have mail.
• 10:37
  Speaker 1: And in fact, your grandma would probably prefer that.
• 10:41
  Speaker 2: And so physics has some things to say about this, right, Like,
• 10:44
  Speaker 2: first of all, it would be very hard for it
• 10:45
  Speaker 2: to be instantaneous, you know, for you to see what's
• 10:48
  Speaker 2: happening on the other side of the planet, like literally
• 10:50
  Speaker 2: right now with zero time delay, would require information to
• 10:54
  Speaker 2: get from there to here with no time gap, and
• 10:58
  Speaker 2: that would violate relativity. Of course, used one of the
• 11:01
  Speaker 2: loopholes like warp drives or wormholes.
• 11:03
  Speaker 1: You mean, like you could open maybe a wormhole between
• 11:06
  Speaker 1: here and the other side of the world, and then
• 11:08
  Speaker 1: the information would flow from there to hear faster than
• 11:11
  Speaker 1: lightwood in regular space.
• 11:13
  Speaker 2: Yeah, exactly, if you opened a wormhole between here and China,
• 11:16
  Speaker 2: then you could pass information between here and there faster
• 11:18
  Speaker 2: than an email would get from here to China. And
• 11:21
  Speaker 2: email travels essentially at the speed of light minus of course,
• 11:24
  Speaker 2: all the time for switching in computation.
• 11:26
  Speaker 1: So you're saying it is possible to see things with
• 11:29
  Speaker 1: your mind that are happening somewhere else, or that happen
• 11:31
  Speaker 1: a few milliseconds before somewhere else.
• 11:34
  Speaker 2: Physics doesn't rule that out. You know, you'd have to
• 11:36
  Speaker 2: create a wormhole, which we don't know how to do,
• 11:38
  Speaker 2: and we don't know if wormholes are real, and then
• 11:41
  Speaker 2: that wormhole would have to be stable enough for you
• 11:43
  Speaker 2: to see that stuff. And to keep wormholes open, you
• 11:45
  Speaker 2: need some sort of like exotic, negatively charged matter that
• 11:48
  Speaker 2: we don't know if it exists, and you'd have to
• 11:51
  Speaker 2: do that somehow, like inside your brain, without also like
• 11:54
  Speaker 2: liquefying your brain, which seems pretty challenging.
• 11:57
  Speaker 1: Like somehow your brain, the cells and your brain would
• 12:00
  Speaker 1: have to be capable of like absorbing these signals and
• 12:03
  Speaker 1: interpreting them.
• 12:04
  Speaker 2: Yeah, exactly creating that wormhole, understanding it, and surviving it.
• 12:08
  Speaker 2: That all seems pretty challenging, but I can't tell you that.
• 12:12
  Speaker 2: Physics says it's impossible.
• 12:14
  Speaker 1: All right, So that's a check for the supernatural here.
• 12:18
  Speaker 1: What about telekinesis, the idea of moving things with your
• 12:22
  Speaker 1: mind that are far away or maybe not so far away,
• 12:25
  Speaker 1: but that are not connected to you.
• 12:27
  Speaker 2: Yeah, telekinesis is also really fascinatingly connected to ideas in physics.
• 12:31
  Speaker 2: Telekinesis is essentially moving something with your brain, as you said,
• 12:35
  Speaker 2: And you know, for a long time there was a
• 12:37
  Speaker 2: puzzle in physics, something called action at a distance, like
• 12:41
  Speaker 2: if two electrons are separated in space, they can still
• 12:44
  Speaker 2: push on each other. How does that happen? It was
• 12:46
  Speaker 2: a big puzzle for a long time, you know, without
• 12:49
  Speaker 2: actually touching, how do two things push on each other?
• 12:53
  Speaker 2: And now, of course we have a solution to that.
• 12:55
  Speaker 2: We know that electrons push on each other using fields
• 12:58
  Speaker 2: that they create. So around each electron on is a
• 13:00
  Speaker 2: field and when electron feels the field of the other electron,
• 13:05
  Speaker 2: or alternatively, you can think about it as them exchanging
• 13:08
  Speaker 2: virtual photons, which is fundamentally the same so physics has
• 13:11
  Speaker 2: a way for two things to push and pull on
• 13:14
  Speaker 2: each other even when they're not touching.
• 13:16
  Speaker 1: Well, I think in physics, basically everything pulls and pushes
• 13:20
  Speaker 1: on each other without touching, because nothing really touches in physics, right,
• 13:23
  Speaker 1: everything is a point particle, which means that they never
• 13:25
  Speaker 1: really touch.
• 13:26
  Speaker 2: Well, you can either say nothing really touches, or you
• 13:29
  Speaker 2: can say that's what touching is. And so you kind
• 13:31
  Speaker 2: of are touching at a distance because you know nothing
• 13:34
  Speaker 2: really has these surfaces, I think is what you're trying
• 13:36
  Speaker 2: to get at when you say they're point particles. There
• 13:39
  Speaker 2: aren't these like surfaces that touch in there some sort
• 13:41
  Speaker 2: of like deep tactile force and the end is just
• 13:44
  Speaker 2: the four fundamental forces and they all operate this way.
• 13:47
  Speaker 2: So that's sort of what touching is. And my point
• 13:49
  Speaker 2: is you can do it at a distance, right. You
• 13:52
  Speaker 2: can pull on something from far away if you can
• 13:54
  Speaker 2: create the right kinds of fields. So you want to
• 13:56
  Speaker 2: levitate your coffee from across the room to you, if
• 13:59
  Speaker 2: you could somehow create the right electromagnetic fields, you could
• 14:03
  Speaker 2: do that because your coffee is made of charged particles.
• 14:06
  Speaker 1: Right, Because I guess everything as we don't understanding. In physics,
• 14:09
  Speaker 1: everything acts at a distance.
• 14:10
  Speaker 2: Right, Everything acts at a distance?
• 14:12
  Speaker 1: Yes, so everything is telikinesis. Right, there's no non there's
• 14:16
  Speaker 1: no regular kinesis in physics. There's only telekinesis.
• 14:19
  Speaker 2: That makes it sound like everything is just like brains
• 14:22
  Speaker 2: thinking about stuff. But yes, everything is action at a distance.
• 14:25
  Speaker 2: In physics, everything is at a distance.
• 14:28
  Speaker 1: But I guess it would be hard. I wonder to
• 14:30
  Speaker 1: lift the coffee mug using the electromagnetic force, because the
• 14:34
  Speaker 1: coffee mug is sort of electrically neutral, right, unless you say,
• 14:37
  Speaker 1: unless you like supercharge your coffee mug.
• 14:39
  Speaker 2: Yeah, the coffee mug is typically neutral and you don't
• 14:42
  Speaker 2: want to have to, like, you know, rub static electricity
• 14:44
  Speaker 2: on it to move it across the room. But it
• 14:45
  Speaker 2: is made out of charged particles, and so if you
• 14:48
  Speaker 2: wove your electromagnetic fields in just the right way, then
• 14:51
  Speaker 2: I think you could transfer momentum to it.
• 14:53
  Speaker 1: I guess if maybe, like the coffee mug was a
• 14:55
  Speaker 1: giant magnet for example, or are you thinking it could
• 14:58
  Speaker 1: be done in a regular mug.
• 15:00
  Speaker 2: If we're being crazy here and there's no limit to
• 15:02
  Speaker 2: your technology, if you could craft the electromagnetic fields in
• 15:05
  Speaker 2: a way that you like, push the positive particles one
• 15:07
  Speaker 2: way with one field and push the negative particles with
• 15:10
  Speaker 2: another field. Then you could move them together across the room.
• 15:13
  Speaker 1: Wait, what do you mean, like have two kinds of
• 15:15
  Speaker 1: electromic getty forces?
• 15:17
  Speaker 2: Positive particles and negative particles are not literally on top
• 15:20
  Speaker 2: of each other. So if you created an electromagnetic field
• 15:23
  Speaker 2: that was highly variable in distance, it was like sculpted
• 15:26
  Speaker 2: to perfectly match the shape of your mug and the
• 15:29
  Speaker 2: location of all the positive negative they charged particles, then
• 15:32
  Speaker 2: you could give it a coherent push in the direction
• 15:34
  Speaker 2: that you wanted.
• 15:35
  Speaker 1: Whoa Like you could single out the electrons in a
• 15:39
  Speaker 1: coffee mug and single out the positive charges separately and
• 15:43
  Speaker 1: somehow shoot a force at each one.
• 15:45
  Speaker 2: Yeah, I like that. We're talking about telekinesis, and your
• 15:47
  Speaker 2: tone is like, Daniel, you're being unrealistic.
• 15:51
  Speaker 1: Well, we're trying to go on with a real answer, right, Yeah.
• 15:55
  Speaker 1: I mean it's theoretically possible. I guess you could single
• 15:58
  Speaker 1: out the trillions of electrons the mug. But but to
• 16:01
  Speaker 1: do it with your mind, I wonder if that would
• 16:02
  Speaker 1: maybe exceed the computational processing of your brain.
• 16:06
  Speaker 2: Almost certainly, I'm not saying that would be easy. But
• 16:08
  Speaker 2: I'm just reaching for a way to move your mug
• 16:11
  Speaker 2: across the room, and I'm thinking technically, theoretically that might
• 16:14
  Speaker 2: be possible.
• 16:15
  Speaker 1: It sounds easier to just ask your sug to bring it.
• 16:18
  Speaker 2: And pay them for it, I hope. But there's another
• 16:20
  Speaker 2: issue there with your brain, which is if physics says
• 16:23
  Speaker 2: momentum is conserved, so if you push on an object,
• 16:26
  Speaker 2: there's an equal and opposite force that pushes back. You know,
• 16:29
  Speaker 2: like if you fire a rifle, there's a recoil. So
• 16:32
  Speaker 2: if you're transferring momentum using your brain to the mug,
• 16:35
  Speaker 2: then this can be some momentum also on your brain. Right,
• 16:38
  Speaker 2: so your brain pushes on an object, basically that object
• 16:41
  Speaker 2: is also pushing on your brain, and that could be
• 16:44
  Speaker 2: quite uncomfortable.
• 16:45
  Speaker 1: I guess yeah, Like if you want to throw the
• 16:47
  Speaker 1: mug across the room, then you kind of need you
• 16:49
  Speaker 1: would feel that forcing with your head. But if I guess,
• 16:51
  Speaker 1: if you're just moving it like within arm reach on
• 16:54
  Speaker 1: top of a table, you probably wouldn't feel a huge
• 16:56
  Speaker 1: amount of force on your brain, would you. I mean,
• 16:58
  Speaker 1: your brain is pretty heavy too.
• 17:00
  Speaker 2: But if you're like magneto and you're lifting like a
• 17:02
  Speaker 2: steam engine or something that's going to liquify your brain.
• 17:06
  Speaker 1: Also, that is pretty mind blowing if agnito exists. So
• 17:10
  Speaker 1: that's a rule. Well, okay, now let's get to the
• 17:12
  Speaker 1: juicy one. What about ghosts.
• 17:14
  Speaker 2: Yeah, you know, I thought about this for a while,
• 17:16
  Speaker 2: and I guess it depends on what you mean by ghosts.
• 17:19
  Speaker 2: If ghosts are just like apparitions that appear human like
• 17:23
  Speaker 2: and make human like noises, then sure than anything could
• 17:27
  Speaker 2: appear to be human. But if you're talking about like
• 17:29
  Speaker 2: actual spirits of dead people, like the continuing thought processes
• 17:34
  Speaker 2: of their brains after their bodies have ceased to live
• 17:36
  Speaker 2: and maybe even decomposed, it's hard for me to understand
• 17:39
  Speaker 2: how that's possible. I mean, there is quantum information, and
• 17:42
  Speaker 2: quantum information is not destroyed, and so technically the quantum
• 17:46
  Speaker 2: information of those people lives on in the universe. But
• 17:50
  Speaker 2: that doesn't mean that it's coherent in a way that
• 17:52
  Speaker 2: could like speak to you and answer questions. Wait, wait,
• 17:55
  Speaker 2: I feel like there's two things here going on. First
• 17:57
  Speaker 2: of all, it's like, can things be ghostly like, can
• 18:01
  Speaker 2: things kind of be in this world but not really
• 18:04
  Speaker 2: be in this world? Or can things, you know, sort
• 18:06
  Speaker 2: of appear to you and go through walls and things
• 18:08
  Speaker 2: like that. And second is can your spirit or your
• 18:10
  Speaker 2: consciousness or what makes you somehow live on after you
• 18:14
  Speaker 2: die or be transformed into something that is ghostly? Oh,
• 18:16
  Speaker 2: I see, well, things being ghostly. Yeah, that's easy because
• 18:19
  Speaker 2: we basically live in a ghostly world. I mean, surrounding
• 18:22
  Speaker 2: us are all sorts of particles that are transparent to us,
• 18:26
  Speaker 2: and we're transparent to them, neutrinos, dark matter, other stuff
• 18:29
  Speaker 2: we haven't even detected. So there's lots of stuff facing
• 18:33
  Speaker 2: through our walls and through us and through our lives
• 18:36
  Speaker 2: all the time that we don't detect. Yeah.
• 18:38
  Speaker 1: In fact, there's the idea out there that maybe dark
• 18:41
  Speaker 1: matter is complicated and could be forming structures and maybe
• 18:44
  Speaker 1: you know, biological things, and maybe even sort of like
• 18:47
  Speaker 1: sentient dark matter beings kind of living in our universe
• 18:50
  Speaker 1: but us never knowing they're there.
• 18:52
  Speaker 2: That's certainly possible. Would you be able to see them
• 18:55
  Speaker 2: and detect them as ghosts? That's harder for me to
• 18:58
  Speaker 2: understand the reason these things are ghost it's because they
• 19:00
  Speaker 2: almost never interact with us, and they do, it wouldn't
• 19:03
  Speaker 2: be in some sort of coherent way, you'd see like
• 19:06
  Speaker 2: one particle here in one particle there.
• 19:08
  Speaker 1: But they do affect our world in some ways, right, Like,
• 19:11
  Speaker 1: for example, dark matter affects us gravitationally, and neutrinos affects
• 19:16
  Speaker 1: us through the weak force.
• 19:17
  Speaker 2: Right, dark matter does affect us gravitationally, but only on
• 19:20
  Speaker 2: really big scales, Like we can't even detect the effect
• 19:23
  Speaker 2: of dark matter on our solar system. We have super
• 19:25
  Speaker 2: high precision measurements of like the orbit of Jupiter, and
• 19:29
  Speaker 2: we can totally ignore dark matter when we do those
• 19:31
  Speaker 2: calculations because it's spread so thin and it's so dilute
• 19:35
  Speaker 2: that it has basically no impact on anything local. So
• 19:38
  Speaker 2: you're not going to see like a dark matter ghost.
• 19:41
  Speaker 1: Well sort of, maybe I wonder this is recording nuts here?
• 19:45
  Speaker 1: Could it dark matter being somehow use their brain to
• 19:48
  Speaker 1: focus gravitational force onto like particular molecules or atoms or particles,
• 19:54
  Speaker 1: just like we were moving the mug earlier. Could they
• 19:56
  Speaker 1: do telekinesis using gravity on us?
• 19:58
  Speaker 2: Perhaps they could remember the so that gravity is the
• 20:01
  Speaker 2: weakest force in the universe by a lot. So to
• 20:05
  Speaker 2: have any sort of gravitational effect on something, you need
• 20:07
  Speaker 2: a very very large mass and there just isn't that
• 20:10
  Speaker 2: much dark matter around. Like in the volume of the
• 20:13
  Speaker 2: Earth is about one squirrel's worth of dark matter, So
• 20:16
  Speaker 2: one squirrel's worth of gravity is about the biggest impact
• 20:19
  Speaker 2: dark matter could have on Earth.
• 20:21
  Speaker 1: So I think you're saying there is ghostly matter in
• 20:23
  Speaker 1: the universe, matter that exists out there that could be
• 20:26
  Speaker 1: organized into things. But then if it does exist, it'd
• 20:28
  Speaker 1: be hard for it to interact with us, and so
• 20:30
  Speaker 1: it'd be hard for us to ever see it.
• 20:32
  Speaker 2: Yeah, exactly, And you certainly wouldn't see it as your
• 20:34
  Speaker 2: grumpy uncle come back to life to haunt your living room.
• 20:38
  Speaker 1: But what if I take my grumpy uncle and he's
• 20:42
  Speaker 1: a billionaire and he puts all his money into downloading
• 20:46
  Speaker 1: his consciousness or scanning his brain, or creating an AI
• 20:50
  Speaker 1: that replicates his consciousness, that he uses his money further
• 20:54
  Speaker 1: to create a neutrino or dark matter version of himself.
• 20:59
  Speaker 2: Wow, your family's pretty crazy, That's what I gotta say
• 21:02
  Speaker 2: about that. It's certainly technically possible to do a quantum
• 21:05
  Speaker 2: copy of your information into some storage medium, and so
• 21:09
  Speaker 2: in principle, perhaps in the future one could upload yourself
• 21:13
  Speaker 2: into the cloud. I don't know, about creating a neutrino
• 21:16
  Speaker 2: version of yourself, though again neutrino is almost impossible to.
• 21:19
  Speaker 1: Interact with, or maybe like a dark matter version of yourself, but.
• 21:23
  Speaker 2: We don't even know what dark matter is. If it's
• 21:25
  Speaker 2: made of particles, how to interact with it? If you
• 21:27
  Speaker 2: could do anything but gravity. I suppose the computer version
• 21:30
  Speaker 2: of your grumpy uncle could be hooked up to like
• 21:32
  Speaker 2: a projector which creates, you know, a holographic image of
• 21:36
  Speaker 2: your uncle, and in that way could be sort of
• 21:38
  Speaker 2: like a ghost.
• 21:39
  Speaker 1: Oh, there you go, a dark matter projector using a
• 21:44
  Speaker 1: quantum copy of your uncle.
• 21:46
  Speaker 2: It doesn't even have to be dark matter, just like
• 21:48
  Speaker 2: a normal matter projector making a hologram.
• 21:51
  Speaker 1: Right, Oh, yeah, there you go. You don't even need
• 21:53
  Speaker 1: dark matter.
• 21:55
  Speaker 2: Yeah. So I suppose in that way a ghost could exist,
• 21:57
  Speaker 2: a physics ghost.
• 21:58
  Speaker 1: All right, Well, hopefully I can convin my uncle to
• 22:01
  Speaker 1: leave the money to me rather than to create a
• 22:04
  Speaker 1: holograms of himself.
• 22:06
  Speaker 2: Just send your son over there to do a bunch
• 22:08
  Speaker 2: of chores and then send them a bill.
• 22:10
  Speaker 1: There you go. There's always a way in physics. All right,
• 22:12
  Speaker 1: Let's get into our other questions. We have awesome questions
• 22:15
  Speaker 1: about neutrinos and neutron stars, and about the nature and
• 22:19
  Speaker 1: origin of space itself. So we'll dig into those, but
• 22:23
  Speaker 1: first let's take our quick break. We're answering listening questions
• 22:38
  Speaker 1: here today, and there is our forty second episode where
• 22:41
  Speaker 1: we do that forty two is a pretty significant number,
• 22:43
  Speaker 1: isn't it?
• 22:43
  Speaker 2: Forty two is a big deal. It's a running joke
• 22:45
  Speaker 2: in my family since we've read it a Hitchhiker's Guide
• 22:48
  Speaker 2: in the Galaxy several years ago.
• 22:49
  Speaker 1: What's the running joke?
• 22:50
  Speaker 2: I guess we just take special joy in seeing the
• 22:52
  Speaker 2: number forty two appear all over the place.
• 22:55
  Speaker 1: It is sort of an interesting number, right, It's six
• 22:57
  Speaker 1: times seven.
• 22:59
  Speaker 2: What's interesting about that?
• 23:00
  Speaker 1: I don't know. It's take an odd number of times
• 23:01
  Speaker 1: an even number. I don't know.
• 23:03
  Speaker 2: I do wonder sometimes what made Douglas Addas choose that
• 23:05
  Speaker 2: number and not, you know, thirty nine or one hundred
• 23:08
  Speaker 2: and forty one or something else.
• 23:10
  Speaker 1: Maybe because it's six ninety seven, as.
• 23:15
  Speaker 2: If that's an answer somehow, like the way you say that,
• 23:18
  Speaker 2: as if it answers the question.
• 23:19
  Speaker 1: Isn't it Jackie Robinson's number two?
• 23:21
  Speaker 4: Yeah?
• 23:21
  Speaker 2: Could be, I don't know.
• 23:22
  Speaker 1: Anyways, we're answering questions from listeners because everyone has questions
• 23:26
  Speaker 1: and we'd like to answer them here on the podcast sometimes.
• 23:29
  Speaker 1: And so our second question here today is about neutrinos
• 23:32
  Speaker 1: and neutron stars.
• 23:33
  Speaker 4: You've mentioned that a neutrino can penetrate a light year
• 23:37
  Speaker 4: of lead, but how much neutron star matter can a
• 23:41
  Speaker 4: neutrino penetrate? Could we study a neutron star that is
• 23:46
  Speaker 4: paired with a main sequence star using the neutrinos from
• 23:50
  Speaker 4: the main sequence star.
• 23:52
  Speaker 1: Right, an interesting question here about neutrinos and neutron stars.
• 23:55
  Speaker 1: There's a lot to unpack here, but basically, neutrinos are ghostly,
• 23:59
  Speaker 1: as we just talked about earlier, and neutron stars are
• 24:01
  Speaker 1: super dense, and so I think they're asking what happens
• 24:04
  Speaker 1: if you put them together.
• 24:05
  Speaker 2: Yeah, it's a really great question, not just because it
• 24:08
  Speaker 2: seeks to understand, like neutrino's a deeper level, but it's
• 24:11
  Speaker 2: got an idea in it, right, an idea to help
• 24:13
  Speaker 2: us probe the interior of neutron stars. We'd love to
• 24:16
  Speaker 2: know what's going on in these crazy, super dense regions
• 24:20
  Speaker 2: of space, these hot squeezed relics. At the end of stars,
• 24:25
  Speaker 2: and so it's a cool idea to imagine like shooting
• 24:27
  Speaker 2: a beam of neutrinos through it and seeing what happens.
• 24:31
  Speaker 1: So we talked about what a neutrino is. There are
• 24:33
  Speaker 1: particles that exist out there in the universe. They get
• 24:36
  Speaker 1: made by the sound. There's a whole bunch of them
• 24:37
  Speaker 1: going through us right now. But they don't interact with
• 24:39
  Speaker 1: things using the electromagnetic force. They seem to only interact
• 24:44
  Speaker 1: using the weak force, right.
• 24:45
  Speaker 2: That's right. Neutrinos have no electric charge, and so they
• 24:48
  Speaker 2: don't interact with photons, and they don't interact at all
• 24:51
  Speaker 2: using electromagnetism, which is really the strongest force that people
• 24:55
  Speaker 2: feel in their everyday lives, you know, lightning and magnetism
• 24:59
  Speaker 2: and the chemical bonds that hold things together. That's all electromagnetism.
• 25:03
  Speaker 2: Neutrinos only feel the weak force, which is much much
• 25:06
  Speaker 2: weaker than electromagnetism. And so that's why we often say
• 25:09
  Speaker 2: that neutrinos can pass through like a wall of lead
• 25:13
  Speaker 2: that's a light year thick without interacting. And it's not
• 25:16
  Speaker 2: because they're like wiggling around those lead particles. It's not
• 25:20
  Speaker 2: because they're super duper small. It's because they just don't
• 25:23
  Speaker 2: interact very often. Every time a neutrino comes near an
• 25:26
  Speaker 2: atom like rolls to die. But that die is like
• 25:29
  Speaker 2: a billion sided dye, and only if it comes up
• 25:32
  Speaker 2: one number, one specific number does the neutrino interact.
• 25:35
  Speaker 1: And so I guess the idea is to pair that
• 25:37
  Speaker 1: idea with the idea of a neutron star. So, now, Daniel,
• 25:40
  Speaker 1: what is a neutron star.
• 25:42
  Speaker 2: A neutron star is the endpoint of a big star
• 25:44
  Speaker 2: that's burned and burned and burned. Remember, most stars start
• 25:47
  Speaker 2: out as overwhelmingly hydrogen, but gravity squeezes them down and
• 25:51
  Speaker 2: ignites fusion at their core, which makes heavier and heavier elements.
• 25:55
  Speaker 2: You take hydrogen mechelium, you squeeze the helium together, you
• 25:58
  Speaker 2: can make carbon. You can heavier stuff all the way
• 26:01
  Speaker 2: up to iron if you have a really big, hot star.
• 26:04
  Speaker 2: But at the end of its life, a star will
• 26:06
  Speaker 2: implode or explode, depending exactly on the mass that it has,
• 26:09
  Speaker 2: and usually leave behind a very hot, dense relic the
• 26:12
  Speaker 2: leftover bits of the fusion that it couldn't burn. And
• 26:15
  Speaker 2: so a neutron star is an extraordinarily dense object. They
• 26:19
  Speaker 2: usually have something like the mass of the Sun but
• 26:22
  Speaker 2: a radius of like ten kilometers. So you're talking about
• 26:25
  Speaker 2: like taking the Sun and squeezing it down to the
• 26:27
  Speaker 2: size of Manhattan after putting it in a blender, and
• 26:31
  Speaker 2: that's a crazy dense object.
• 26:33
  Speaker 1: Yeah, we've talked about how it's basically like the bestest
• 26:36
  Speaker 1: thing you can get in the universe, almost before you
• 26:38
  Speaker 1: get a black hole.
• 26:39
  Speaker 2: Yeah, gravity is trying to squeeze it down even further,
• 26:42
  Speaker 2: but there's this degeneracy pressure. The quantum effects inside the
• 26:46
  Speaker 2: neutron star are still able to resist gravity. If you
• 26:49
  Speaker 2: add a little bit more mass, then the thing will
• 26:51
  Speaker 2: collapse into a black hole, but it's still resistant. So
• 26:54
  Speaker 2: it's like the last stronghold against gravity's ultimate victory.
• 26:58
  Speaker 1: And I think part of the reason is that it
• 27:00
  Speaker 1: is made out of neutrons, right, so they don't repel
• 27:02
  Speaker 1: each other electromagnetically. They have no almost no reason not
• 27:07
  Speaker 1: to just fall into themselves, not to get crushed together.
• 27:10
  Speaker 2: Except that neutrons are fermions. They're spin one half particles,
• 27:13
  Speaker 2: which means that like electrons, they can't overlap too much.
• 27:17
  Speaker 2: They can't be in the same quantum state, so they
• 27:19
  Speaker 2: resist being pushed together. So that's one way in which
• 27:22
  Speaker 2: a neutron star is preventing itself from collapsing into a
• 27:26
  Speaker 2: black hole. There's this degeneracy pressure. The neutrons don't want
• 27:29
  Speaker 2: to be in the same quantum state.
• 27:31
  Speaker 1: Right, right, But I think what I meant was, like,
• 27:33
  Speaker 1: the reason I don't fall to the enter of the
• 27:34
  Speaker 1: Earth is because my electrons are being repelled by the
• 27:37
  Speaker 1: electrons of the floor.
• 27:39
  Speaker 2: Yeah, that's right, and that's not happening inside neutron.
• 27:41
  Speaker 1: Stars because it's all neutral.
• 27:43
  Speaker 2: It's all neutral electromagnetically. But you know, we also don't
• 27:46
  Speaker 2: think that it's really still neutrons at the core of
• 27:48
  Speaker 2: neutron stars. We think that the strong force is probably
• 27:51
  Speaker 2: doing something crazy, something else that you know, the distinction
• 27:55
  Speaker 2: between the neutrons is blurring, and all the quarks inside
• 27:58
  Speaker 2: them are really interacting with each other. Episode about what's
• 28:01
  Speaker 2: going on the heart of neutron stars, But the bottom
• 28:03
  Speaker 2: line is that we don't know, and it's probably something
• 28:06
  Speaker 2: super fascinating that would tell us something new about the
• 28:08
  Speaker 2: way the strong force works and the way that it
• 28:10
  Speaker 2: competes with gravity. So super interesting, almost like learning about
• 28:14
  Speaker 2: what's inside a black hole.
• 28:16
  Speaker 1: Okay, so now the question is we have the the
• 28:19
  Speaker 1: desest thing in the universe before a black hole, and
• 28:22
  Speaker 1: we have something that doesn't really like to interact with anything.
• 28:25
  Speaker 1: What happens if you shoot a nutrino into a neutron star.
• 28:28
  Speaker 2: Yeah, so this is really a question about transparency. We
• 28:31
  Speaker 2: recently did an episode all about transparency and photons, and
• 28:35
  Speaker 2: the short version of that is that it depends on
• 28:37
  Speaker 2: the interaction. You have to think about it from a
• 28:39
  Speaker 2: particle physics point of view. Shoot the particle through, is
• 28:41
  Speaker 2: it going to interact with the stuff? And when you're
• 28:44
  Speaker 2: talking about transparency for normal materials, like why can light
• 28:48
  Speaker 2: go through air and why can it go through glass
• 28:51
  Speaker 2: but it can't go through steel or can't go through
• 28:53
  Speaker 2: your hand, then again it's depending on those interactions. You're
• 28:56
  Speaker 2: thinking about whether the photon can be absorbed by the
• 28:59
  Speaker 2: electrons in your body. Sometimes those electrons can absorb that
• 29:03
  Speaker 2: photon because there's an energy level available for them to
• 29:06
  Speaker 2: get to, and sometimes they can't, so the photon just
• 29:08
  Speaker 2: flies through and ignores the material. So that's why photons
• 29:12
  Speaker 2: can go through matter. Sometimes if the energy states aren't
• 29:15
  Speaker 2: arranged in a way that the photon can absorb it.
• 29:18
  Speaker 2: So now when we think about a neutrino going through
• 29:21
  Speaker 2: a neutron star, we have to ask similar questions like
• 29:23
  Speaker 2: how can the neutrino interact with that material and is
• 29:26
  Speaker 2: there sort of a valid particle physics process that would
• 29:29
  Speaker 2: allow that to happen.
• 29:31
  Speaker 1: Well, as far as we know, neutrinos are neutral, so
• 29:34
  Speaker 1: they don't feel the electromagnetic force, but they do feel
• 29:37
  Speaker 1: the weak force. Right, do they feel the strong force
• 29:39
  Speaker 1: as well or only the weak force?
• 29:41
  Speaker 2: If they have mass, then they feel gravity, and we
• 29:43
  Speaker 2: do think that they have masks, though we can't measure
• 29:45
  Speaker 2: it very precisely, but their mass, if they have any,
• 29:48
  Speaker 2: is very very small, and so gravity is probably almost
• 29:51
  Speaker 2: irrelevant for neutrinos. So really it just comes down to
• 29:54
  Speaker 2: the weak force. So if you're a neutrino and you're
• 29:56
  Speaker 2: approaching a neutron star it's filled with neutrons, then what
• 29:59
  Speaker 2: you can do is interact with one of the quarks
• 30:02
  Speaker 2: inside the neutron. For example, you can take a down
• 30:05
  Speaker 2: quark and you can convert it to an upquark, interacting
• 30:08
  Speaker 2: with it because those quarks also feel the weak force.
• 30:12
  Speaker 2: This is called reverse beta decay. Sentially, a neutrino hits
• 30:16
  Speaker 2: a neutron, turns it into a proton, and then you
• 30:19
  Speaker 2: can an electron out the other side.
• 30:22
  Speaker 1: So there is a process for a nutrina to interact
• 30:24
  Speaker 1: with a quark, is what you're saying exactly.
• 30:27
  Speaker 2: You can either do this convert a nucleon from a
• 30:29
  Speaker 2: neutron to a proton, or it could just kick one
• 30:32
  Speaker 2: of the nucleons. The reason it's got two options is
• 30:35
  Speaker 2: because there's sort of two versions of the photon for
• 30:38
  Speaker 2: the weak force. Electromagnetism just has the photon, but the
• 30:41
  Speaker 2: weak force has the W and the Z, and the
• 30:44
  Speaker 2: neutrino can use either one. You can either use a
• 30:46
  Speaker 2: Z to sort of give a kick to one of
• 30:48
  Speaker 2: the nucleons, or it can use the W to convert
• 30:51
  Speaker 2: one of the nucleons from a neutron to a proton.
• 30:54
  Speaker 1: I'm not sure I follow all the mechanics, but I
• 30:55
  Speaker 1: think what I'm saying is if I shoot a nutrino
• 30:58
  Speaker 1: into a neutron, start it iss for it to interact
• 31:01
  Speaker 1: with a quark, in which case it would get stopped
• 31:03
  Speaker 1: by the quark. Basically right, it'd be like hitting the cork.
• 31:06
  Speaker 2: It wouldn't necessarily get stopped, but it might get scattered
• 31:09
  Speaker 2: amount like change direction, or it might even be absorbed
• 31:11
  Speaker 2: and get converted into an electron.
• 31:13
  Speaker 1: But it wouldn't go through as the main point.
• 31:16
  Speaker 2: It might go through. There's a possibility for a neutrino
• 31:18
  Speaker 2: to interact with these things, but the probability of it
• 31:21
  Speaker 2: happening depends on a lot of different factors. It still
• 31:24
  Speaker 2: has to roll that big die and come up with
• 31:25
  Speaker 2: the right number, but sort of the number of sizes
• 31:28
  Speaker 2: of that dye depends on a few things. One of
• 31:30
  Speaker 2: the things that depends on is the energy of the neutrino.
• 31:34
  Speaker 2: If the neutrino is higher energy, if it's moving faster,
• 31:37
  Speaker 2: then it has a higher probability to interact with the material.
• 31:41
  Speaker 2: So a faster moving neutrino is more likely to bump
• 31:44
  Speaker 2: into one of these nucleons, and a slower moving neutrino
• 31:47
  Speaker 2: is less likely.
• 31:48
  Speaker 1: But if it does interact, then it's sort of like
• 31:51
  Speaker 1: it's it wouldn't count as going through unscathed, right.
• 31:55
  Speaker 2: That's right. Any interaction doesn't count as going through unscathed.
• 31:58
  Speaker 2: So it depends on two things. It depends on the
• 32:00
  Speaker 2: neutrino's energy, and that's actually interesting. It's because of relativity.
• 32:04
  Speaker 2: If you're moving really really fast, then space in front
• 32:07
  Speaker 2: of you is looking contracted, which means that you're squeezing
• 32:10
  Speaker 2: this already very dense neutron star. You're squeezing it down
• 32:13
  Speaker 2: even further so it looks even denser. So you like
• 32:16
  Speaker 2: length contract the neutron star into something even smaller, which
• 32:19
  Speaker 2: makes you have a higher probability of interacting with it.
• 32:22
  Speaker 2: So higher energy neutrinos, faster neutrinos, have a bigger probability
• 32:27
  Speaker 2: of being absorbed by the neutron star or being bent
• 32:29
  Speaker 2: by it.
• 32:30
  Speaker 1: So the neutron star is super dense. That means that
• 32:33
  Speaker 1: it basically, as a neutrino's trying to go through it,
• 32:35
  Speaker 1: there are a lot of possibilities or it's very likely
• 32:38
  Speaker 1: for it to interact with a quirk, which means it
• 32:41
  Speaker 1: wouldn't go through necessarily. Have you done the math like
• 32:43
  Speaker 1: how far can a neutrino penetrate?
• 32:45
  Speaker 2: So it did sit down to do this calculation, and
• 32:47
  Speaker 2: it turns out it also really depends very strongly on
• 32:50
  Speaker 2: the temperature of the neutron star. So neutron stars, remember
• 32:55
  Speaker 2: there are these degenerate states, which means that like all
• 32:58
  Speaker 2: the quantum states are filled up, so cold neutron star
• 33:01
  Speaker 2: has all those neutrons filling up the lowest energy states,
• 33:05
  Speaker 2: and that's a problem for interaction because if you're coming
• 33:07
  Speaker 2: through in your neutrino and you're trying to bump into
• 33:10
  Speaker 2: one of those neutrons, there's sort of no available state
• 33:13
  Speaker 2: for it to get to. Like the ladder above, it
• 33:15
  Speaker 2: is all filled, so it can't interact with the neutrino
• 33:18
  Speaker 2: because there's nowhere for it to go. On a hotter
• 33:20
  Speaker 2: neutron star, some of those states are not totally filled
• 33:24
  Speaker 2: because the neutrons are moving around they have higher energy,
• 33:26
  Speaker 2: so there's open spots in the ladder, and if a
• 33:29
  Speaker 2: neutrino comes by, it can interact with that neutron because
• 33:32
  Speaker 2: there's a spot for the neutron to jump up to.
• 33:34
  Speaker 2: So for hotter neutron stars, they're more likely to interact.
• 33:38
  Speaker 2: So you have a high energy neutrino hitting a very
• 33:40
  Speaker 2: hot neutron star than it can interact.
• 33:43
  Speaker 1: Which means it wouldn't penetrate very.
• 33:45
  Speaker 2: Much exactly, which is sort of cool because it means
• 33:48
  Speaker 2: that neutron stars start out opaque to neutrinos and as
• 33:52
  Speaker 2: they cool, they become transparent, and there's this threshold it
• 33:56
  Speaker 2: like ten to the ten degrees kelvin, that's like ten
• 34:00
  Speaker 2: billion kelvin that neutron stars essentially become completely transparent to neutrinos.
• 34:06
  Speaker 1: Do neutron stars cool?
• 34:08
  Speaker 2: Neutron stars do cool absolutely, very slowly over time. They're
• 34:12
  Speaker 2: still radiating out heat. They're not fusing, right, They're not
• 34:14
  Speaker 2: creating more energy at their cores, but there's still hot
• 34:18
  Speaker 2: lumps of matter, and hot lumps of matter do radiate
• 34:20
  Speaker 2: out photons.
• 34:22
  Speaker 1: I guess maybe another question is, if they are really
• 34:24
  Speaker 1: close to being black holes, wouldn't they also bend the
• 34:27
  Speaker 1: space around them and somehow trap neutrinos that way, or
• 34:31
  Speaker 1: at least bend their path.
• 34:32
  Speaker 2: Yeah, that's a great question. Neutron stars are definitely dense
• 34:35
  Speaker 2: enough to have very strong gravitational effects, you know. That's
• 34:38
  Speaker 2: why they're almost perfectly spherical. Like you try to make
• 34:41
  Speaker 2: a mountain on the surface of a neutron star, it
• 34:43
  Speaker 2: will get flattened. The tallest mountain on the surface of
• 34:46
  Speaker 2: a neutron star is like a millimeter high, so it's
• 34:49
  Speaker 2: very intense gravity, but there's no event horizon, right, that's
• 34:52
  Speaker 2: the difference between something that's a black hole and something
• 34:54
  Speaker 2: that's not so. In principle, photons and even neutrinos created
• 34:58
  Speaker 2: at the heart of a neutron star can and still
• 35:00
  Speaker 2: escape because there's no event horizon. But you're right, it
• 35:03
  Speaker 2: will get distorted, like bent around in lots of different directions.
• 35:06
  Speaker 1: Right. So, I guess if you shoot neutrino's at entron star,
• 35:09
  Speaker 1: it would only maybe go through on scathe if you
• 35:13
  Speaker 1: shoot it at the exact center of the neutron star,
• 35:16
  Speaker 1: I wonder. And also if it has, as you said,
• 35:19
  Speaker 1: the right energy to it, and the neutron star is
• 35:22
  Speaker 1: cool enough, then it will go through. But otherwise it
• 35:24
  Speaker 1: might get deflected or it might hit one of the
• 35:26
  Speaker 1: quarks in the star exactly.
• 35:28
  Speaker 2: And here we've mostly focused on the hot mess that's
• 35:31
  Speaker 2: at the heart of the neutron star. The densest region,
• 35:33
  Speaker 2: the crust of the neutron star, like the surface of it,
• 35:36
  Speaker 2: is not nearly as dense.
• 35:38
  Speaker 1: All right, Well, I think that's the answer to the
• 35:40
  Speaker 1: question here. How much can neutrinos penetrate a neutron star.
• 35:43
  Speaker 1: It sounds like the answer is it depends on the
• 35:46
  Speaker 1: speed of the neutrino and also the temperature of the
• 35:49
  Speaker 1: neutron star. But it sounds like if it's the right conditions,
• 35:52
  Speaker 1: then it wouldn't penetrate very far, or at least it
• 35:54
  Speaker 1: would maybe get bent for sure, almost definitely by the
• 35:57
  Speaker 1: gravity of the neutron starm.
• 35:58
  Speaker 2: Which means something cool, means that Doug is right that
• 36:01
  Speaker 2: in principle, you could use a beam of neutrinos that's
• 36:05
  Speaker 2: going through a very hot neutron star to learn something
• 36:08
  Speaker 2: about what's inside that neutron star based on how those
• 36:12
  Speaker 2: neutrinos are bent or stopped.
• 36:14
  Speaker 1: Mmm, like an X ray kind of like you could
• 36:16
  Speaker 1: shoot some neutrinos at intrustar have a detector in the
• 36:19
  Speaker 1: back of it, and you can kind of get an
• 36:21
  Speaker 1: X ray of the neutron star.
• 36:23
  Speaker 2: Yeah, or if there's a bright star behind the neutron star,
• 36:25
  Speaker 2: it's already doing that for us, shooting the neutrinos at us.
• 36:29
  Speaker 2: So we just got to find those and use it
• 36:31
  Speaker 2: as a way to X ray that neutron star.
• 36:33
  Speaker 1: Maybe my rich uncle will pay for that detector. We'll see,
• 36:37
  Speaker 1: we'll see what we can convince him to do. All right,
• 36:39
  Speaker 1: let's get to our last question here, and it's about
• 36:42
  Speaker 1: space and how it gets made. So let's dig into that,
• 36:46
  Speaker 1: but first let's take another quick break. All right, we're
• 37:01
  Speaker 1: answering questions from listeners. We've answered awesome questions about ghosts, telekinesis,
• 37:06
  Speaker 1: the supernatural or I guess how we can make the
• 37:09
  Speaker 1: supernatural natural? And we've answered questions about Neutrino's and some
• 37:13
  Speaker 1: of the densest objects in the universe. Now we have
• 37:16
  Speaker 1: our last question here today, and it comes from a
• 37:19
  Speaker 1: six year old named James.
• 37:21
  Speaker 3: Hi.
• 37:21
  Speaker 1: Daniel, Hi, my name is Change and I just turned six,
• 37:28
  Speaker 1: and how does space get made? Awesome question? Thank you James,
• 37:33
  Speaker 1: and happy birthday. Do you think he's getting paid to
• 37:36
  Speaker 1: be a physicist.
• 37:37
  Speaker 2: I think he's got a future career ahead.
• 37:39
  Speaker 1: Of him for sure, getting paid in cereal and ice cream.
• 37:45
  Speaker 2: I wonder if James's question is why does space exist,
• 37:49
  Speaker 2: like how did it get made in the beginning originally?
• 37:52
  Speaker 2: Or if he's asking about how space expands, how we
• 37:55
  Speaker 2: get more space?
• 37:57
  Speaker 1: What are the words he used?
• 37:58
  Speaker 2: He says, I'm wondering about how space gets made.
• 38:00
  Speaker 1: Well, let's see he used the words I wonder how
• 38:02
  Speaker 1: space gets made. So it sounds like it's in the
• 38:07
  Speaker 1: present tense right, like, how are space being made?
• 38:10
  Speaker 3: Right now?
• 38:10
  Speaker 2: Yeah? I guess he's sort of asking for a recipe, like, Hey,
• 38:13
  Speaker 2: I want to make more space? What do I do?
• 38:15
  Speaker 1: Which I guess is maybe the same question as if
• 38:17
  Speaker 1: you put in the past ask, which is how did it? Space?
• 38:19
  Speaker 2: Can be like when you go to somebody's house and
• 38:22
  Speaker 2: they serve a really delicious dessert and you're like, wow,
• 38:25
  Speaker 2: how does that pie get made?
• 38:26
  Speaker 1: That seems like a red question.
• 38:28
  Speaker 2: Oh, that's very polite. It's saying I want more of
• 38:31
  Speaker 2: that thing you made.
• 38:32
  Speaker 1: Well, we could all use a little bit more space,
• 38:34
  Speaker 1: for sure, especially down here in southern California, where space
• 38:37
  Speaker 1: set a premium, And the question is a physical one,
• 38:40
  Speaker 1: I guess about physics, not just like how do you
• 38:41
  Speaker 1: make more room in your house?
• 38:43
  Speaker 2: Yeah? I think it's about the nature of space itself. Right,
• 38:45
  Speaker 2: When you take everything out of the universe, you strip
• 38:48
  Speaker 2: it of all of its particles and its energy. We're
• 38:51
  Speaker 2: talking about this stuff that everything is existing in. How
• 38:55
  Speaker 2: does that itself get made? Yeah?
• 38:57
  Speaker 1: Or maybe James has a sibling and he's wondering when
• 39:00
  Speaker 1: he has to stop sharing a room with that something,
• 39:03
  Speaker 1: how can I get more space?
• 39:04
  Speaker 2: Well, we're spending a lot of time joking around about
• 39:06
  Speaker 2: the question and not answering it. And one reason is
• 39:08
  Speaker 2: that we really just don't have any good answers. You know,
• 39:11
  Speaker 2: one of the deepest mysteries in modern physics is even
• 39:15
  Speaker 2: like what is space anyway? We still don't even really understand.
• 39:19
  Speaker 2: We know that we need to move beyond sort of
• 39:21
  Speaker 2: ancient notions of space from like Newton that space is
• 39:25
  Speaker 2: absolute like a backdrop of the universe, but we don't
• 39:28
  Speaker 2: really have a great idea for what space actually is.
• 39:31
  Speaker 1: Well, I feel like it's sort of been one of
• 39:33
  Speaker 1: the biggest mind blowing moments in humanity in the last
• 39:36
  Speaker 1: one hundred years to realize that the space is being
• 39:39
  Speaker 1: made right now, Like there's more space today than there
• 39:42
  Speaker 1: was yesterday in the universe.
• 39:43
  Speaker 2: Yeah, about one hundred years ago, people thought that the
• 39:45
  Speaker 2: universe was static. There was just a bunch of stars
• 39:47
  Speaker 2: hanging out in space, and it was that way, it
• 39:50
  Speaker 2: had always been that way. Then we learned that the
• 39:52
  Speaker 2: universe was expanding, and Einstein's general relativity actually accommodates that
• 39:56
  Speaker 2: very very nicely, even without later confusion about excit expansion
• 40:01
  Speaker 2: or decelerating expansion. Just the idea that the universe was
• 40:04
  Speaker 2: expanding at all meant that space itself was increasing, right,
• 40:09
  Speaker 2: not just stuff moving through space, but actual increase in
• 40:12
  Speaker 2: the amount of space.
• 40:14
  Speaker 1: Yeah, space is being made right now, And I guess
• 40:16
  Speaker 1: the question is, like how do you make space or
• 40:18
  Speaker 1: like where does space come from?
• 40:19
  Speaker 2: We don't know the answer to that. We know that
• 40:21
  Speaker 2: it is happening, and we can describe it mathematically, and
• 40:25
  Speaker 2: we have some pretty good handles on like when space
• 40:27
  Speaker 2: will contract and when space will expand, but we don't
• 40:31
  Speaker 2: know what space is, so we don't have really any
• 40:33
  Speaker 2: insight into that process itself. We know that the universe
• 40:37
  Speaker 2: is doing it and a long way breaking some rules
• 40:39
  Speaker 2: we used to think were fundamental, like when the universe
• 40:42
  Speaker 2: makes space, it makes a new chunk of space that
• 40:45
  Speaker 2: comes with new quantum fields which have non zero energy
• 40:48
  Speaker 2: in them, which means, in principle, is increasing the total
• 40:52
  Speaker 2: energy of the universe. So making more space involves creating
• 40:56
  Speaker 2: energy from nothing, which is not something we know how
• 40:59
  Speaker 2: to do. So yeah, we really don't have any idea
• 41:02
  Speaker 2: for how this works.
• 41:03
  Speaker 1: I think you're saying that, like, all we know right
• 41:05
  Speaker 1: now is that there is some space today there in
• 41:08
  Speaker 1: between the stars that we can see and tomorrow there's
• 41:11
  Speaker 1: more space, but there's going to be more space between
• 41:13
  Speaker 1: those stars. That's kind of how we see it. That's
• 41:16
  Speaker 1: just what we can observe.
• 41:17
  Speaker 2: That's what we observe. And it's not like we're totally clueless, right,
• 41:20
  Speaker 2: General relativity gives us a mathematical description for that expansion.
• 41:25
  Speaker 2: We can describe it, we can even predict it that,
• 41:27
  Speaker 2: we can explain the history of it, but like the
• 41:29
  Speaker 2: deep underlying mechanism of that is not something that we
• 41:33
  Speaker 2: understand at all, because again, we don't even know what
• 41:35
  Speaker 2: the thing itself is. We have this sort of high
• 41:38
  Speaker 2: level mathematical story from Einstein, but we don't understand the
• 41:42
  Speaker 2: microphysics of it, like how does space come together? What
• 41:45
  Speaker 2: are the essential bits of it? We don't even know
• 41:47
  Speaker 2: if space itself is fundamental, Like could you have a
• 41:51
  Speaker 2: universe without space or is space like a prerequisite a
• 41:55
  Speaker 2: minimum condition for even having a universe. We don't even
• 41:58
  Speaker 2: know the answer to that totally basic question about the
• 42:02
  Speaker 2: nature of space.
• 42:03
  Speaker 1: You mean, like we don't know what space is in
• 42:05
  Speaker 1: the first place, right.
• 42:06
  Speaker 2: Yeah, and so we don't know if you have to
• 42:08
  Speaker 2: have it, right, maybe there's a place where space.
• 42:10
  Speaker 1: Isn't now maybe to answer then James's question, like how
• 42:13
  Speaker 1: does space get made? Like what does that process look like?
• 42:16
  Speaker 1: I wonder if maybe that's one of the questions he's
• 42:18
  Speaker 1: wondering about, Like is space being created smoothly sort of
• 42:23
  Speaker 1: like you know, like a balloon being inflated smoothly, or
• 42:27
  Speaker 1: does it get created in chunks or in steps?
• 42:30
  Speaker 2: What do you think another great question I would love
• 42:32
  Speaker 2: to have the answer to. It depends on whether space
• 42:36
  Speaker 2: is smooth and continuous or quantum mechanical, like in Einstein's
• 42:40
  Speaker 2: description of general relativity, space is continuous. Between any two points,
• 42:44
  Speaker 2: there's an infinite number of steps, and you can continue
• 42:47
  Speaker 2: to divide those as long as you'd like. Quantum mechanical
• 42:50
  Speaker 2: views of space say that's not true, that there must
• 42:52
  Speaker 2: be like space pixels, that everything is discrete. And if
• 42:56
  Speaker 2: that's true, then as the universe expands, then you pop
• 42:59
  Speaker 2: out new countable numbers of space pixels, right, like one
• 43:04
  Speaker 2: more and then one another one. You can't have like
• 43:06
  Speaker 2: one and a half more space pixels. So whether it's
• 43:09
  Speaker 2: continuous or discrete depends on whether space is sort of
• 43:12
  Speaker 2: classical and smooth or quantum mechanical and discrete and we
• 43:16
  Speaker 2: don't know the answer to that either.
• 43:18
  Speaker 1: One of their other possibilities for like explaining what we
• 43:21
  Speaker 1: see out there. Is it possible we're shrinking and space
• 43:24
  Speaker 1: is the same where we're just shrinking. Just seems like
• 43:27
  Speaker 1: space is getting bigger.
• 43:28
  Speaker 2: That's absolutely possible. Remember the expansion of space absolutely yeah.
• 43:32
  Speaker 1: I was just pulling that out of out of my pocket. There.
• 43:37
  Speaker 2: The expansion of space is relative. It's a scale factor
• 43:40
  Speaker 2: we measure as space expands relative to its size in
• 43:43
  Speaker 2: the past, And it's mathematically equivalent to say space is
• 43:47
  Speaker 2: expanding and stuff is staying the same size, or space
• 43:51
  Speaker 2: is staying the same size and everything is shrinking. You
• 43:54
  Speaker 2: can never tell the difference between those two things because
• 43:57
  Speaker 2: they would only be different relative to some external ruler
• 44:00
  Speaker 2: which doesn't exist.
• 44:02
  Speaker 1: Wait, what does that even mean? Now? I was literally
• 44:05
  Speaker 1: just making up words, but it sounds like it's a
• 44:07
  Speaker 1: real possibility. What does that mean? Like we're getting smaller
• 44:12
  Speaker 1: relative to like, let's say, like us and our sun
• 44:15
  Speaker 1: here and there's another star in the sky, we're getting smaller.
• 44:18
  Speaker 1: Would that necessarily make the space between us bigger?
• 44:21
  Speaker 2: Imagine the expanding universe? Right, this is your usual picture
• 44:25
  Speaker 2: everything's staying the same size and getting further and further apart.
• 44:27
  Speaker 2: And we think that's probably infinite. But just imagine like
• 44:30
  Speaker 2: a chunk of it, and now, instead of allowing that
• 44:33
  Speaker 2: to get bigger and bigger, try holding it to be
• 44:35
  Speaker 2: the same size, so as time goes on, you don't
• 44:38
  Speaker 2: allow it to expand. In order to keep all the
• 44:40
  Speaker 2: relationships the same. You can instead just squeeze everything down.
• 44:44
  Speaker 2: So like now you're holding that chunk of space and
• 44:46
  Speaker 2: you're watching it, and instead of it getting bigger, so
• 44:49
  Speaker 2: things get further apart, everything just shrinks inside of it,
• 44:52
  Speaker 2: so it gets smaller and smaller. So then the beings
• 44:55
  Speaker 2: on those little planets, they measure the distances to be
• 44:58
  Speaker 2: larger because they're rulers are.
• 45:00
  Speaker 1: Shrinking, even the ruler between like here and there.
• 45:02
  Speaker 2: Yes, everything within it shrinks. And so if you don't
• 45:05
  Speaker 2: have an external metric, if you're not that alien outside,
• 45:08
  Speaker 2: you know, running the simulation holding that chunk of space,
• 45:11
  Speaker 2: you can't tell the difference. If you're inside the universe,
• 45:14
  Speaker 2: you can't tell the difference between stuff shrinking and space
• 45:17
  Speaker 2: staying the same, or everything staying the same size and
• 45:20
  Speaker 2: space increasing.
• 45:22
  Speaker 1: And that would apply even to things like light. Right, Like,
• 45:25
  Speaker 1: as the universe expands, we see light being stretched DoD,
• 45:28
  Speaker 1: I mean the light itself. The photons are shrinking, or
• 45:31
  Speaker 1: the speed of light is shrinking.
• 45:32
  Speaker 2: Everything stays the same relative to that ruler. But those
• 45:34
  Speaker 2: rulers are shrinking. So yes, whoa.
• 45:37
  Speaker 1: And it's time shrinking as well, or time stays the same.
• 45:40
  Speaker 2: Time stays the same in these pictures, it's space that's shrinking. Whoa.
• 45:44
  Speaker 1: So maybe space is not being made. They were just
• 45:47
  Speaker 1: getting you know, shorter with age.
• 45:50
  Speaker 2: I don't know. I mean, if you're shrinking, doesn't that
• 45:52
  Speaker 2: make more space for you? I mean if you said, hey, Daniel,
• 45:55
  Speaker 2: I want a bigger house, and then I like shrunk
• 45:57
  Speaker 2: you in your family down the half size, you'd be like, oh, awesome,
• 46:00
  Speaker 2: houses down twice as bien.
• 46:01
  Speaker 1: I think there's a movie with Matt Damon about that
• 46:04
  Speaker 1: that's been made already. But what's an important distinction, though,
• 46:09
  Speaker 1: isn't there? Like that means that space is not being made.
• 46:12
  Speaker 1: It's not sort of a thing that's being created. We're
• 46:15
  Speaker 1: just drinking.
• 46:16
  Speaker 2: If according to the people on those planets, they're measuring
• 46:18
  Speaker 2: greater distances between stuff, then I would say, yes, space
• 46:22
  Speaker 2: is still being made in both scenarios.
• 46:25
  Speaker 1: I see, you can make space by vacating it or
• 46:27
  Speaker 1: by making an addition to your hous is what you're saying.
• 46:30
  Speaker 2: Yeah, by either increasing the distances or shrinking the rulers.
• 46:33
  Speaker 2: It's the same thing.
• 46:34
  Speaker 1: So you're saying, as I get older and my house
• 46:36
  Speaker 1: is going to get bigger automatically, whereas for my kids
• 46:39
  Speaker 1: right now, the house is just getting smaller and smaller.
• 46:42
  Speaker 2: Physics says, yes.
• 46:43
  Speaker 1: It's a family affairs. What I'm saying, All right, So
• 46:45
  Speaker 1: I guess the answer for James is that, unfortunately, we
• 46:48
  Speaker 1: don't really know how space gets made. We just know
• 46:51
  Speaker 1: that it is being made out there in space, or
• 46:53
  Speaker 1: at least it seems like it's getting made.
• 46:55
  Speaker 2: Yeah, that's right. We don't understand space. There's all these
• 46:58
  Speaker 2: fascinating mysteries. And it feels like the kind of thing
• 47:00
  Speaker 2: where in fifty years or one hundred years, people are
• 47:03
  Speaker 2: going to look back and be like, oh, my gosh,
• 47:04
  Speaker 2: the answer was so obvious it was staring them in
• 47:07
  Speaker 2: the face, but they were so stuck in their old
• 47:09
  Speaker 2: way of thinking they just couldn't see it.
• 47:11
  Speaker 1: Just sounds like maybe if James keeps asking questions there's
• 47:15
  Speaker 1: a lot of space for him to maybe find the
• 47:17
  Speaker 1: answer to these questions.
• 47:19
  Speaker 2: There's plenty of space for everybody out there to contribute
• 47:22
  Speaker 2: knowledge at the forefront of human ignorance.
• 47:24
  Speaker 1: And hopefully enough money out there to pay them also
• 47:28
  Speaker 1: in the future. All right, well, thanks to everyone for
• 47:31
  Speaker 1: sending in their questions. We enjoy answering questions. We hope
• 47:35
  Speaker 1: you enjoyed that. Thanks for joining us, see you next time.
• 47:46
  Speaker 2: Thanks for listening, and remember that Daniel and Jorge Explain
• 47:49
  Speaker 2: the Universe is a production of iHeartRadio. For more podcasts
• 47:53
  Speaker 2: from iHeart Radio, visit the iHeartRadio app, Apple Podcasts, or
• 47:57
  Speaker 2: wherever you listen to your favorite show.