Latest / Daniel and Kelly’s Extraordinary Universe / Listener Questions #32

Transcript

Listener Questions #32 · Daniel and Kelly’s Extraordinary Universe

• 0:07
  Speaker 1: Is the universe's expansion just entropiece show. No, it's the
• 0:12
  Speaker 1: cosmic stretch that lets disorder grow.
• 0:16
  Speaker 2: I live an envy of rip Van Winkle. I just
• 0:18
  Speaker 2: can't stay asleep. But if I take a sleep aid,
• 0:22
  Speaker 2: will I rest longer but less deep?
• 0:25
  Speaker 1: Could aliens evolve epic nap skills for the long cosmic ride?
• 0:30
  Speaker 1: Or yeat themselves across space? On pure physics pride.
• 0:35
  Speaker 2: Whatever questions keep you up at night, Daniel and Kelly's
• 0:38
  Speaker 2: answers will make it right.
• 0:40
  Speaker 1: Welcome to Daniel and Kelly's Extraordinary Universe. Listener Questions number
• 0:45
  Speaker 1: thirty two.
• 0:47
  Speaker 3: Woo Hello.
• 1:02
  Speaker 2: I'm Kelly Waider Smith and it currently hurts to laugh.
• 1:04
  Speaker 2: So this is one of the few instances in my
• 1:06
  Speaker 2: life where I wish my friend and co host Daniel
• 1:09
  Speaker 2: was less funny.
• 1:12
  Speaker 1: Hi, I'm Daniel. I'm a particle physicist and I never
• 1:15
  Speaker 1: thought being funny was dangerous.
• 1:17
  Speaker 2: Oh it's not usually, It really really isn't usually.
• 1:22
  Speaker 1: But it is fun to consider yourself dangerously funny.
• 1:24
  Speaker 2: Oh yes, yes, we all enjoy fiction from diamonds.
• 1:30
  Speaker 1: Ooh, I love the instant karma. Every time you throw
• 1:34
  Speaker 1: a jab you feel it.
• 1:36
  Speaker 2: Yeah, you know, I think what I'm what I'm learning
• 1:39
  Speaker 2: about myself is that I laugh at myself a lot,
• 1:43
  Speaker 2: and I think I'm very funny, which is maybe not
• 1:47
  Speaker 2: a great personal trait.
• 1:49
  Speaker 1: It's a little dangerous.
• 1:50
  Speaker 2: It turns out, Yeah, I guess so ooh okay. So
• 1:55
  Speaker 2: here's my question for you. So you used the word
• 1:58
  Speaker 2: yeat and one of in the poem in the intro,
• 2:02
  Speaker 2: and yeat is a word that specifically reminds me that
• 2:06
  Speaker 2: I am old, because it was one of the first
• 2:08
  Speaker 2: words that I remember hearing where I was like, oh,
• 2:11
  Speaker 2: I don't know what that means, but I don't want
• 2:14
  Speaker 2: to tell someone I don't know what it means, because
• 2:16
  Speaker 2: it's clearly one of the cool words that people are
• 2:18
  Speaker 2: using now and I just have to figure it out
• 2:19
  Speaker 2: through context. And so yeat was like my initiation into
• 2:25
  Speaker 2: being one of the not cool older people. Do you
• 2:28
  Speaker 2: have a moment where you were like, oh, I have
• 2:32
  Speaker 2: reached the age where I don't get the things.
• 2:34
  Speaker 1: Well, I have a teenage daughter, so I hear a
• 2:37
  Speaker 1: lot of words I have to interpret in context. For example,
• 2:42
  Speaker 1: it took me a while to understand what sleigh really meant,
• 2:45
  Speaker 1: like what exactly is a good sleigh and how do
• 2:47
  Speaker 1: you start every day with the sleigh? And now, of
• 2:50
  Speaker 1: course that I've mastered it, it's like so embarrassing to
• 2:54
  Speaker 1: use that word, because nobody uses that word. So I
• 2:57
  Speaker 1: love how language is flexible and how it evolves, and
• 3:01
  Speaker 1: how my teenager lets me put my thumb on the
• 3:04
  Speaker 1: linguistic pulse of America.
• 3:05
  Speaker 2: How your teenager lets you sort of strangle America by
• 3:10
  Speaker 2: like making it not fun anymore as soon as you
• 3:13
  Speaker 2: understand it.
• 3:14
  Speaker 1: Yeah, exactly, spoiling fun as parents do.
• 3:18
  Speaker 2: Yeah, yeah, it's certainly what I do.
• 3:19
  Speaker 1: And on this episode, we're hoping did not spoil your fun,
• 3:22
  Speaker 1: but answer your questions, which we hope is a fun
• 3:24
  Speaker 1: resolution to those mysteries we are scratching your curiosity.
• 3:29
  Speaker 2: Yeah, well, the good news is our listeners are a
• 3:30
  Speaker 2: lot more fun than we are, and that kind of
• 3:32
  Speaker 2: makes us fun by associations. So let's start with Sonia's question,
• 3:37
  Speaker 2: and let's go ahead and listen to it.
• 3:39
  Speaker 4: I have a question about time. So years ago I
• 3:43
  Speaker 4: read a book called flat Land, and I think it
• 3:45
  Speaker 4: had a sequel called sphere Land, which I read as well,
• 3:48
  Speaker 4: and it was an incredible explanation of dimensions, including time
• 3:54
  Speaker 4: as a dimension. It did also have some hilarious sexism
• 3:57
  Speaker 4: in it that I think men in nice logical shapes
• 4:00
  Speaker 4: and women are small pointy lines and if they bump
• 4:03
  Speaker 4: into the men, the men explode and die I mean
• 4:06
  Speaker 4: Freudian or what. But aside from that, it made it
• 4:10
  Speaker 4: possible to understand how time could be a dimension. But
• 4:13
  Speaker 4: then I was thinking that time is the only dimension
• 4:15
  Speaker 4: that you can only move in one direction, that you
• 4:17
  Speaker 4: experience it only going forwards, And I often wondered is
• 4:22
  Speaker 4: that related to the fact that the universe is expanding?
• 4:25
  Speaker 4: Is it like space, time is growing and our consciousness
• 4:29
  Speaker 4: sits on the growing edge of it, and as it
• 4:32
  Speaker 4: grows we experience it going forward. Or is it something
• 4:37
  Speaker 4: to do with maybe just falling like gravity and time
• 4:43
  Speaker 4: pulling us forward, like you know, what is pulling us
• 4:47
  Speaker 4: in this direction? Why can we not slide backwards and
• 4:52
  Speaker 4: forwards in time in the way that we could in space.
• 4:55
  Speaker 2: That's it really okay? So I am definitely interested in
• 5:00
  Speaker 2: hilarious sexism. Or are we talking about like, you know,
• 5:04
  Speaker 2: watching a movie from the eighties where you know, the
• 5:08
  Speaker 2: women are like just blonde and need to be saved,
• 5:11
  Speaker 2: or like, what are we talking about.
• 5:13
  Speaker 1: Here, no flatline goes even further back, and it's sort
• 5:16
  Speaker 1: of like a time capsule of casual sexism from the
• 5:20
  Speaker 1: middle of last century. Oh yeah, exactly.
• 5:23
  Speaker 3: Oh.
• 5:23
  Speaker 2: I mean sometimes I can be hilarious but also really frustrated.
• 5:28
  Speaker 1: I wonder if he was even commented on at the time,
• 5:30
  Speaker 1: or if it's just like, hey, this is just how
• 5:32
  Speaker 1: we talk about women. Anyway, it's fascinating.
• 5:35
  Speaker 2: You know. The other day I got my gallbladder removed,
• 5:39
  Speaker 2: which wasn't a ton of fun. But right as they
• 5:41
  Speaker 2: were rolling me into the operating theater, I looked around
• 5:44
  Speaker 2: and I said, wait a minute, you're all women. This
• 5:48
  Speaker 2: is awesome. And they were like, yeah, that is pretty awesome.
• 5:53
  Speaker 2: I guess they were kind of used to it, but anyway,
• 5:55
  Speaker 2: I thought it was pretty great that everybody rolling me
• 5:58
  Speaker 2: into that room was a woman. Anyway, we've made some progress,
• 6:01
  Speaker 2: still some room for improvement. Let's talk about time as
• 6:05
  Speaker 2: a dimension.
• 6:06
  Speaker 1: Yeah, so, Sonya's question essentially is why does time go forward?
• 6:10
  Speaker 1: If time is a dimension, why can't we slide backwards
• 6:12
  Speaker 1: and forwards? And how does it related to the expansion
• 6:15
  Speaker 1: of the universe and all this kind of stuff. So
• 6:17
  Speaker 1: let's start at the beginning, and remember what we know
• 6:19
  Speaker 1: about time and space. Space is three dimensional. You can
• 6:23
  Speaker 1: go backwards and forwards. If you define an arbitrary reference frame,
• 6:27
  Speaker 1: you put yourself at zero, then you're always at the
• 6:29
  Speaker 1: same place. If you define the center of the Earth
• 6:31
  Speaker 1: to be zero, then you can move all around. You
• 6:34
  Speaker 1: can come back and revisit where you were born. There
• 6:37
  Speaker 1: is no arbitrary reference frame, but if you pick one,
• 6:40
  Speaker 1: you can go backwards and forwards. In space, time we
• 6:43
  Speaker 1: think of a little bit differently, but Albert Einstein showed
• 6:46
  Speaker 1: us that time and space are deeply connected. In fact,
• 6:49
  Speaker 1: he wraps them together into a four dimensional object called
• 6:52
  Speaker 1: space time.
• 6:54
  Speaker 2: And one of the first episodes you and I recorded
• 6:56
  Speaker 2: together was what is time and what is space? And
• 7:01
  Speaker 2: those are some really fun philosophical topics to think about
• 7:06
  Speaker 2: deeply while looking at the stars, I think, and this.
• 7:09
  Speaker 1: Is a really important and subtle point here, which is like,
• 7:12
  Speaker 1: why do you put things together? Is it more than
• 7:14
  Speaker 1: just I'm tacking on another dimension? Is it meaningful in
• 7:18
  Speaker 1: some way? And it really is. We only do this
• 7:21
  Speaker 1: when it makes more sense to group things than it
• 7:23
  Speaker 1: does to divide things, like with electricity and magnetism. We
• 7:27
  Speaker 1: notice that these two things are really two parts of
• 7:30
  Speaker 1: the same larger object, and we had drawn an artificial
• 7:34
  Speaker 1: dotted line between them, and now we see that it
• 7:36
  Speaker 1: makes much more sense to connect them and to think
• 7:38
  Speaker 1: of them as one larger hole, because, for example, in
• 7:41
  Speaker 1: special relativity, we know that what somebody sees as an
• 7:43
  Speaker 1: electric fields, somebody else can see is electric and magnetic.
• 7:46
  Speaker 1: It's observer dependent, so it really is one larger hole.
• 7:50
  Speaker 1: And it's the same story with space and time. Things
• 7:53
  Speaker 1: get simpler, they get more beautiful, more elegant when you
• 7:56
  Speaker 1: treat it as one larger hole rather than two separate things.
• 8:00
  Speaker 1: Specifically in special relativity, when you think about what's happening
• 8:04
  Speaker 1: in the universe and you want to translate from what
• 8:07
  Speaker 1: one observer sees to what another observer sees, who's like
• 8:10
  Speaker 1: somewhere else and maybe moving fast, it's just rotating a
• 8:14
  Speaker 1: four dimensional vector. Because space and time is one four
• 8:18
  Speaker 1: D object and a frame is like a four D vector.
• 8:21
  Speaker 1: You just rotate that four D vector and all the
• 8:23
  Speaker 1: components mix just the same way, like in linear algebra.
• 8:27
  Speaker 1: If you have a three D vector in space and
• 8:29
  Speaker 1: you rotate it, all the components get mixed together, and
• 8:32
  Speaker 1: that's just because time impacts where things happen, and space
• 8:36
  Speaker 1: impacts when you see them happen. They really are parts
• 8:39
  Speaker 1: of a larger hole, and so it makes perfect sense
• 8:42
  Speaker 1: to stick them together. In fact, the math becomes much
• 8:44
  Speaker 1: simpler if you do. So that's why we stick things together.
• 8:47
  Speaker 1: It's not just.
• 8:48
  Speaker 2: Arbitrary, okay, but where and when are still different. So
• 8:54
  Speaker 2: do you lose anything by lumping them?
• 8:56
  Speaker 1: Yeah? I love that question. Now you don't lose anything.
• 8:59
  Speaker 1: In fact, you gain because all of your intuition for
• 9:02
  Speaker 1: how space works and vectors rotate in space, you can
• 9:06
  Speaker 1: now generalize that to four dimensions and operate on space
• 9:09
  Speaker 1: time in the same way. So it's like you get
• 9:12
  Speaker 1: to bring a whole set of tools along with you. You
• 9:14
  Speaker 1: have to adapt them a little bit, but now you
• 9:16
  Speaker 1: have like a more powerful toolkit to deal with these questions.
• 9:20
  Speaker 1: But you're right that space and time are still different.
• 9:22
  Speaker 1: Like special relativity sees them as very very similar, right,
• 9:25
  Speaker 1: and brings them closer together. But we know they are
• 9:28
  Speaker 1: still different, and the theories of physics that we have
• 9:32
  Speaker 1: actually all trees time differently. So we've been talking about relativity,
• 9:36
  Speaker 1: which combines space and time, but in general relativity it
• 9:40
  Speaker 1: gets even weirder, and you have these more generalized coordinates
• 9:43
  Speaker 1: which you can say are like kind of spacey, and
• 9:45
  Speaker 1: some of them are kind of timy. And in general
• 9:48
  Speaker 1: relativity you can even have theories of the universe where
• 9:50
  Speaker 1: time has a beginning it's like a singularity right before
• 9:54
  Speaker 1: which there is no time. So time is very weird
• 9:57
  Speaker 1: in general relativity, and then in quantum mechanics it's completely different.
• 10:01
  Speaker 1: Quantum mechanics treats time just as a parameter. It separates
• 10:05
  Speaker 1: space and time. It says you have all these fields
• 10:07
  Speaker 1: through space and they evolve over time. And actually quantum mechanics,
• 10:12
  Speaker 1: which insists that no information is lost, requires that time
• 10:16
  Speaker 1: is infinite into the past and into the future, and
• 10:19
  Speaker 1: quantum mechanics is almost symmetric in time. So we have
• 10:22
  Speaker 1: very similar concepts and we use the same word, but
• 10:25
  Speaker 1: time in quantum mechanics and time and relativity really are
• 10:29
  Speaker 1: different concepts, and it's actually one of the obstacles to
• 10:32
  Speaker 1: merging them together into a theory of quantum gravity. And
• 10:36
  Speaker 1: we have even a third concept of time, which of
• 10:38
  Speaker 1: course we just use the same name for, which is
• 10:41
  Speaker 1: thermodynamic time. Right in thermodynamics there actually is an arrow.
• 10:47
  Speaker 1: The universe evolves differently forwards in time and backwards in
• 10:50
  Speaker 1: time because of entropy. The second law thermodynamics says that
• 10:53
  Speaker 1: entropy increases with time, it goes up. So this is asymmetric,
• 10:58
  Speaker 1: and this is what we call thermodynamic arrow of time.
• 11:01
  Speaker 1: The universe goes from lower entropy to higher entropy. And
• 11:05
  Speaker 1: check out our episode a deep dive into entropy, which
• 11:08
  Speaker 1: shows you that's not just like disorder. It's an evolution
• 11:12
  Speaker 1: from improbable states to more probable states. So that's another
• 11:16
  Speaker 1: concept of time, which again doesn't perfectly mesh with quantum
• 11:20
  Speaker 1: mechanics or with relativity. So we have these three different
• 11:23
  Speaker 1: ideas of time.
• 11:25
  Speaker 2: Okay, so I think that I have lost where we
• 11:29
  Speaker 2: are heading to. So now we have we have a
• 11:32
  Speaker 2: lot of different definitions of time. Initially we were trying
• 11:35
  Speaker 2: to lump space and time. The road that we are
• 11:38
  Speaker 2: taking is eventually supposed to get us to wear.
• 11:40
  Speaker 1: Again, so that's our primerund space and time now. So
• 11:43
  Speaker 1: in this question was are we moving forwards in time
• 11:47
  Speaker 1: because the universe is expanding or does this have something
• 11:51
  Speaker 1: to do with gravity? What's pulling us forwards in time? Essentially?
• 11:55
  Speaker 1: And it's true that the expansion of the universe seems
• 11:57
  Speaker 1: to have a direction in time also, right, like, as
• 12:01
  Speaker 1: time goes on, the universe gets bigger and its entropy
• 12:04
  Speaker 1: is growing. So ooh, that feels like maybe there's a
• 12:07
  Speaker 1: connection there. But number one, it's not required for the
• 12:10
  Speaker 1: universe to keep expanding. Like if the universe had had
• 12:14
  Speaker 1: more mass in it and less dark energy, or if
• 12:16
  Speaker 1: it had a different topology, like it was curved more,
• 12:20
  Speaker 1: it could have contracted. Right, the universe when it began expanding,
• 12:24
  Speaker 1: that expansion was initially slowing down. It was always expanding,
• 12:27
  Speaker 1: but that expansion was decelerating until dark energy ramped up
• 12:31
  Speaker 1: and took over and accelerated it. But it could have
• 12:33
  Speaker 1: been in other universes that it decelerated, stopped, and then contracted.
• 12:38
  Speaker 1: So the universe is not required to expand as time
• 12:42
  Speaker 1: goes forward. It's not like thermodynamics, where entropy increases with time.
• 12:46
  Speaker 1: The expansion of the universe could have various directions. Okay,
• 12:50
  Speaker 1: so I don't think the expansion explains why time goes forwards,
• 12:53
  Speaker 1: but it is true that as time goes forward and
• 12:55
  Speaker 1: the universe is expanding, the entropy grows, right, And this
• 12:58
  Speaker 1: is one of The greatest mystery actually about time and entropy,
• 13:02
  Speaker 1: which is that the early universe started out really really
• 13:05
  Speaker 1: low entropy. Right, Enterpy is going to increase, and eventually
• 13:09
  Speaker 1: we're going to reach a maximum entropy where everything is
• 13:12
  Speaker 1: like spread out and there's no useful energy. There's still
• 13:14
  Speaker 1: like energy floating around, but there's no useful energy, no differences, right, Like,
• 13:19
  Speaker 1: if everything is the same temperature, there's no way for
• 13:22
  Speaker 1: energy to flow and for you to do anything. And
• 13:25
  Speaker 1: so that's a pretty boring universe. And what's fascinating is
• 13:28
  Speaker 1: that our universe started out really really far from that.
• 13:30
  Speaker 1: So it's going to take a long time to get
• 13:33
  Speaker 1: to the heat death. It could have been that our
• 13:35
  Speaker 1: universe started out like pretty close to the heat death
• 13:37
  Speaker 1: and like five seconds later we were at the heat death.
• 13:40
  Speaker 1: One of the deep mysteries of cosmology and theroodynamics and
• 13:44
  Speaker 1: time is why we started out with such low entropy.
• 13:48
  Speaker 2: I guess we might not be here if that hadn't
• 13:50
  Speaker 2: been the case.
• 13:50
  Speaker 1: Yeah, so that's a great argument. It's the anthropic one.
• 13:53
  Speaker 1: Only in universes that do start out with very low
• 13:56
  Speaker 1: entropy do you get people asking, hey, why is there
• 13:59
  Speaker 1: such a low entropy? Right? Because the other ones just
• 14:02
  Speaker 1: have a bunch of photons flying around. Another comment on
• 14:05
  Speaker 1: this thermodynamic arrow of time. Some people argue that the
• 14:09
  Speaker 1: thermodynamic era of time is the arrow of time. The
• 14:13
  Speaker 1: fact that entropy grows with time forces time to go forwards,
• 14:17
  Speaker 1: because the second law says entropy has to go up,
• 14:19
  Speaker 1: and therefore time has to go forwards. And I'm not
• 14:21
  Speaker 1: sure I buy that as an argument.
• 14:23
  Speaker 2: You're not sure you buy the second law of thermodynamics
• 14:26
  Speaker 2: full statement, Daniel.
• 14:28
  Speaker 1: Oh no, I'm deeply invested in the second law. But
• 14:31
  Speaker 1: the second law says time and entropy are connected, doesn't
• 14:35
  Speaker 1: say time has to go forwards. You know, if time
• 14:38
  Speaker 1: went the other way, it would just mean that we're
• 14:40
  Speaker 1: in the universe that entropy is decreasing, so it couples
• 14:44
  Speaker 1: time and enter by. But I don't see how it
• 14:45
  Speaker 1: forces time to go this way instead of the other way.
• 14:49
  Speaker 1: Maybe in some other universe where entropy is constantly decreasing,
• 14:52
  Speaker 1: they're wondering why time goes their direction right, which we
• 14:55
  Speaker 1: would call backwards anyway. So nobody knows the answer to
• 14:58
  Speaker 1: this question, Sonyafor we don't know why time is different
• 15:02
  Speaker 1: from space, because it seems so similar. We don't know
• 15:04
  Speaker 1: how to unify time from a throodynamic point of view
• 15:07
  Speaker 1: and a quantum mechanical point of view and a relativity
• 15:10
  Speaker 1: point of view. We hope to one day figure that out.
• 15:12
  Speaker 1: We don't know why time just goes forwards. It does
• 15:15
  Speaker 1: seem somehow connected to entropy, but I don't think it's
• 15:18
  Speaker 1: connected to the expansion of the universe.
• 15:21
  Speaker 2: All right, well, let's yep this answer over to Sonia
• 15:25
  Speaker 2: and see what she has to say. Does it What
• 15:28
  Speaker 2: was the word that Hazel used, slay? All right, let's
• 15:31
  Speaker 2: see if it's slays.
• 15:34
  Speaker 4: Hey, Daniel and Gelli, thank you so much for taking
• 15:37
  Speaker 4: the time to answer my question. I have been bounded
• 15:40
  Speaker 4: officially by my family from trying to use words like sleigh,
• 15:42
  Speaker 4: So I shall just say that was a fantastic unpacking
• 15:46
  Speaker 4: of all the reasons we don't know the answer. I
• 15:48
  Speaker 4: do you think though, over the last twenty thirty years
• 15:51
  Speaker 4: we've made so many advances in understanding. I wonder whether
• 15:55
  Speaker 4: maybe in my lifetime we might work it out. And
• 15:58
  Speaker 4: if we do, maybe you can explain it to me.
• 15:59
  Speaker 3: Then.
• 16:00
  Speaker 4: Thanks again, love the show.
• 16:21
  Speaker 1: All right, we took a little break and we're ready
• 16:24
  Speaker 1: to answer more questions from listeners. So those of you
• 16:27
  Speaker 1: who are gently falling asleep, don't because this question is
• 16:30
  Speaker 1: very important for you. Get up and stretch, do a
• 16:32
  Speaker 1: jumping jack, and pay close attention.
• 16:35
  Speaker 2: Let's go ahead and listen to Thomas's amazing question about sleeping.
• 16:42
  Speaker 5: Hey, this is Matt the sound guy. Thomas was not
• 16:46
  Speaker 5: available to read his questions, so I'll do it in
• 16:49
  Speaker 5: his stead. Hi, I just finished and enjoyed your episode
• 16:55
  Speaker 5: about aging. As a seventy seven year old who exercises daily,
• 16:58
  Speaker 5: I still find my sleep as very disrupted. My question is,
• 17:03
  Speaker 5: if one takes sleep aids i e. ADVILPM or melatonin,
• 17:07
  Speaker 5: is sleep as beneficial?
• 17:12
  Speaker 1: I love this question. I want to know the answer
• 17:14
  Speaker 1: to this question. Also, thank you Thomas for asking it.
• 17:16
  Speaker 2: Well, okay, so maybe this the answer is going to
• 17:18
  Speaker 2: be relevant to you because you indicated that when you
• 17:20
  Speaker 2: turned fifty you started rounding your age up to one hundred.
• 17:24
  Speaker 2: But I specifically set up an answer for this question
• 17:28
  Speaker 2: for the impact of sleep aids on older folks because
• 17:32
  Speaker 2: it turns out that the answers depend a lot on
• 17:36
  Speaker 2: why you aren't sleeping well, which I'll get into. But
• 17:39
  Speaker 2: first I'd like to note that Thomas is referring to
• 17:42
  Speaker 2: the why do We Age episode where we interviewed doctor
• 17:45
  Speaker 2: Vanki Ramakrishnan, and that was from October ninth, twenty twenty five.
• 17:49
  Speaker 1: Super fun conversations, super fun.
• 17:51
  Speaker 2: He's so good at explaining concepts. And Gina Poe, Doctor
• 17:54
  Speaker 2: Gina Poe is also great at explaining ideas, and we
• 17:57
  Speaker 2: had her on to talk about why we sleep and dream?
• 18:00
  Speaker 2: So another great episode to check out. That was August
• 18:02
  Speaker 2: twenty first, twenty twenty five.
• 18:04
  Speaker 1: And so this is gonna be like a crossover between
• 18:05
  Speaker 1: our two episodes.
• 18:06
  Speaker 2: Yeah, kind of a crossover. And I you know, of course,
• 18:09
  Speaker 2: after remind everybody, I am not a medical doctor, and
• 18:12
  Speaker 2: if you are suffering from disrupted sleep, you should talk
• 18:15
  Speaker 2: to a medical professional. And this discussion is in no
• 18:17
  Speaker 2: way comprehensive. Okay.
• 18:21
  Speaker 1: And by a medical professional, do you mean chat gibt
• 18:23
  Speaker 1: or do you mean like an actually human person?
• 18:25
  Speaker 2: I mean an actual human person.
• 18:28
  Speaker 1: Yeah, and yet you use chat GPT for medical advice?
• 18:31
  Speaker 2: Are you talking about my decision to go to the
• 18:33
  Speaker 2: er recently? Yes, no, it's true, I did so. I
• 18:37
  Speaker 2: guess I'll tell that story now. So I was crawling
• 18:40
  Speaker 2: around on the bathroom floor in incredible pain, and I
• 18:45
  Speaker 2: had been in pain all day and I just started
• 18:46
  Speaker 2: throwing up, and Zach was like, you should go to
• 18:49
  Speaker 2: the er, and I was like, I don't want to
• 18:50
  Speaker 2: go to the er because I'm gonna have to sit
• 18:53
  Speaker 2: in an er for hours and be uncomfortable in the
• 18:55
  Speaker 2: horrible chairs, and i just want to find a position
• 18:57
  Speaker 2: where I'm comfortable and I'll stay home all day. And
• 18:59
  Speaker 2: Zach look on chat GPT and chat GPT immediately said,
• 19:03
  Speaker 2: your wife has gallstones. She needs to go to the er.
• 19:06
  Speaker 2: And it was right. I went to the er and
• 19:09
  Speaker 2: they immediately brought me to the back and they were like,
• 19:11
  Speaker 2: you have gallstones.
• 19:14
  Speaker 1: And they didn't use CHATCHEAPT, did they.
• 19:16
  Speaker 2: I hope not? Well. I mean, they eventually gave me
• 19:19
  Speaker 2: an ultrasound and they were like, look, you have gallstones.
• 19:22
  Speaker 2: And turns out I had four gallstones, each about two
• 19:25
  Speaker 2: centimeters wide. And then I looked at my post operative
• 19:28
  Speaker 2: notes and they had to cut a bigger hole where
• 19:30
  Speaker 2: my belly button was because the gallstones were making it
• 19:32
  Speaker 2: so hard to get the gallbladder out because they were
• 19:34
  Speaker 2: so big. Anyway, more than anyone needed to know, chat
• 19:37
  Speaker 2: GPT is sometimes a helpful tool, yes, But in general,
• 19:42
  Speaker 2: if you're having disrupted sleep, which is very common in
• 19:45
  Speaker 2: the elderly population, and if it's bothering you, you should
• 19:48
  Speaker 2: talk to a medical professional, all right. So there are
• 19:53
  Speaker 2: lots of reasons why people have disrupted sleep at various
• 19:56
  Speaker 2: different ages, and those problems can impact the kinds of
• 20:01
  Speaker 2: sleep aids that you might want to take. So some
• 20:03
  Speaker 2: people have a trouble sleeping because of anxiety, or because
• 20:06
  Speaker 2: of depression, or because of pain. But I decided that
• 20:11
  Speaker 2: I was going to look at just problems related to
• 20:14
  Speaker 2: sleep when you're aging. And so for example, when folks age,
• 20:18
  Speaker 2: they produce less melatonin. And melatonin is a hormone that
• 20:21
  Speaker 2: our body uses to control our circadian rhythms. So we
• 20:25
  Speaker 2: make more melatonin when it's supposed to be dark outside
• 20:27
  Speaker 2: at night. That's the part of how our body tells ourselves, oh,
• 20:30
  Speaker 2: it's time to go to sleep, and older people make
• 20:33
  Speaker 2: less of it.
• 20:34
  Speaker 1: Is that the one that people often take when they're
• 20:36
  Speaker 1: on an airplane to help them with jet lag.
• 20:38
  Speaker 2: Yes, exactly, exactly. So one thing I'd like to notice
• 20:42
  Speaker 2: that when I read a bunch of these papers, the
• 20:44
  Speaker 2: first thing that most of these papers said was, Look,
• 20:47
  Speaker 2: if you're having trouble sleeping, the first thing you should
• 20:50
  Speaker 2: try isn't a sleep aid. It's exercise, which Thomas is
• 20:54
  Speaker 2: already doing. And then it's cognitive behavior therapy to improve
• 20:58
  Speaker 2: sleep or other sleep hygiene things. And so there's a
• 21:01
  Speaker 2: bunch of stuff you're supposed to try before you start
• 21:04
  Speaker 2: trying to take medications, because a lot of medications have
• 21:07
  Speaker 2: side effects that are not ideal.
• 21:09
  Speaker 1: So first, like, make sure you get exercise during the day,
• 21:12
  Speaker 1: make sure you're sleeping in a cool, dark, quiet place
• 21:15
  Speaker 1: you don't have like toddlers jumping up and down in
• 21:17
  Speaker 1: your head.
• 21:18
  Speaker 3: This kind of thing.
• 21:19
  Speaker 2: Yes, right, try to avoid looking at screens for the
• 21:21
  Speaker 2: two hours before you go to sleep, stuff like that.
• 21:24
  Speaker 2: So Thomas's question actually kind of has a couple different
• 21:27
  Speaker 2: parts to it. First, you probably want to know does
• 21:30
  Speaker 2: the sleep aid actually help you sleep better? And there's
• 21:34
  Speaker 2: a couple different ways you can measure that. So you
• 21:35
  Speaker 2: can measure does it help you fall asleep more quickly
• 21:38
  Speaker 2: once you lay down in bed? Right, once you fall
• 21:41
  Speaker 2: in asleep, do you wake up less often? If you
• 21:45
  Speaker 2: do wake up, how long does it take you to
• 21:47
  Speaker 2: fall back asleep? And then when you're in bed, what
• 21:50
  Speaker 2: is the total amount of time that you spend sleeping?
• 21:53
  Speaker 2: And those are some ways of measuring your sleep, But
• 21:56
  Speaker 2: another way of measuring sleep quality is things like how
• 22:00
  Speaker 2: deep does your sleep get? So you can put like
• 22:03
  Speaker 2: electrodes on people and you can measure things like rapid
• 22:06
  Speaker 2: eye movement sleep, ri em sleep, and this is where
• 22:09
  Speaker 2: you should go and listen to Gina pose amazing episode.
• 22:12
  Speaker 2: But basically, when your brain is doing rapid eye movement sleep,
• 22:15
  Speaker 2: this is when you're like consolidating memories and like doing
• 22:19
  Speaker 2: all sorts of stuff that our brains and bodies need
• 22:22
  Speaker 2: to do.
• 22:22
  Speaker 1: I feel like this is the heart of his question
• 22:24
  Speaker 1: because he's asking me sleep as beneficial. But are we
• 22:27
  Speaker 1: going to talk about aging and sleep and metrics and
• 22:31
  Speaker 1: not talk about Brian Johnson's data?
• 22:33
  Speaker 2: Go ahead, Daniel.
• 22:37
  Speaker 1: Brian Johnson is this guy who wants to prevent himself
• 22:40
  Speaker 1: from aging, and he takes blood from his eighteen year
• 22:43
  Speaker 1: old son and Jackson himself, and I think a lot
• 22:46
  Speaker 1: of that stuff is really weird. What I do think
• 22:48
  Speaker 1: is fascinating is how much data he takes on himself,
• 22:51
  Speaker 1: including what happens when he sleeps, and he posts all
• 22:55
  Speaker 1: this data online.
• 22:56
  Speaker 2: You love telling this story. You also told you doctor,
• 22:59
  Speaker 2: Thank you, Ramachrisa. We had a Nobel Prize winner on
• 23:02
  Speaker 2: the show, Daniel, and you told him this story. Well,
• 23:06
  Speaker 2: we were looking at each other over the Riverside recording,
• 23:10
  Speaker 2: but go ahead tell everybody so that everybody knows.
• 23:12
  Speaker 1: I want to say. It's just that in a one
• 23:15
  Speaker 1: way to measure your sleep is the length and quality
• 23:19
  Speaker 1: of the erections you have. While my gosh, yes, according
• 23:23
  Speaker 1: to Brian Johnson and the data that he posts daily
• 23:26
  Speaker 1: on his website.
• 23:28
  Speaker 5: Yep.
• 23:28
  Speaker 2: Okay, okay, well that's that. I didn't find that measure
• 23:32
  Speaker 2: in any of the papers that I was looking at.
• 23:37
  Speaker 2: But apparently the sleep that Brian Johnson is having slags and.
• 23:43
  Speaker 1: All right, so what are some ways that people can
• 23:46
  Speaker 1: improve their sleep medically? The kind of sleep aids that
• 23:49
  Speaker 1: Thomas is talking about.
• 23:51
  Speaker 2: Okay, So there's many different kinds of sleep aids that
• 23:53
  Speaker 2: can be delivered in different ways. This is not at
• 23:56
  Speaker 2: all comprehensive, as I've said. One class of drugs that
• 24:00
  Speaker 2: to be used often are benzodiazepines. And what benzodiazepines do
• 24:05
  Speaker 2: is they bind to GABA receptors. So these are receptors
• 24:09
  Speaker 2: that are in our brain. They're on are like nerve cells,
• 24:12
  Speaker 2: and they are important for making our nerves excitatory, which
• 24:16
  Speaker 2: is essentially like making our nerves fire so that our
• 24:20
  Speaker 2: brains are like active and doing stuff.
• 24:22
  Speaker 1: You said, gabba receptors.
• 24:23
  Speaker 2: What's a gabba gabba is just a neurotransmitter. Wasn't going
• 24:28
  Speaker 2: to go into too much detail here, but it's a neurotransmitter.
• 24:31
  Speaker 2: And when that neurotransmitter binds to these receptors in our brain,
• 24:35
  Speaker 2: our nerves start firing and our brains start doing stuff. Okay,
• 24:38
  Speaker 2: but you don't really want your brain to be doing
• 24:40
  Speaker 2: too much stuff. You want your brain to be kind
• 24:42
  Speaker 2: of calming down. And so when when benzodiazepines bind to
• 24:47
  Speaker 2: these receptors, your brain sort of gets less excited and
• 24:50
  Speaker 2: it acts as like a muscle relaxant and a sedative,
• 24:54
  Speaker 2: and you start getting sleepy and the ideas you're supposed
• 24:57
  Speaker 2: to fall asleep. And these drugs were established and then
• 24:59
  Speaker 2: i teen fifties. They were first synthesized in the nineteen fifties,
• 25:03
  Speaker 2: and they were supposed to be a great replacement for barbituates,
• 25:06
  Speaker 2: which had some like negative side effects, and everyone was
• 25:09
  Speaker 2: like yay benzodiazepine, So we started prescribing these for everybody.
• 25:13
  Speaker 2: But it turns out that they're also highly addictive and
• 25:18
  Speaker 2: they do a bunch of bad things. But they might
• 25:22
  Speaker 2: I found a twenty sixteen review for sleep aids for
• 25:26
  Speaker 2: folks who are older, and that review said that benzodiazepines
• 25:30
  Speaker 2: do appear to help you fall asleep faster, help you
• 25:34
  Speaker 2: reach RM sleep faster, So that's sleep where you're doing
• 25:37
  Speaker 2: a better job of consolidating memories, and it reduces the
• 25:40
  Speaker 2: number of times that you wake up in the middle
• 25:42
  Speaker 2: of the night. But I also found a more recent
• 25:45
  Speaker 2: study that suggested that if you use benzodiazepines long term,
• 25:50
  Speaker 2: you're going to spend less time in RM sleep, and
• 25:54
  Speaker 2: so in that case quality would be lower, So long
• 25:57
  Speaker 2: term use would be giving you less good sleep. This
• 26:00
  Speaker 2: all sounds good, but the way that older bodies metabolize
• 26:04
  Speaker 2: or like breakdown drugs is different than the way that
• 26:08
  Speaker 2: younger bodies do, and in some ways it's less efficient,
• 26:11
  Speaker 2: and so these drugs spend more time in your body,
• 26:13
  Speaker 2: they do different things in your body. So the American
• 26:16
  Speaker 2: Geriatric Society recommends not using benzodiazepines because in elderly patients.
• 26:22
  Speaker 2: These drugs are associated with cognitive impairment, delirium, You're more
• 26:28
  Speaker 2: likely to fall, you're more likely to get fractures, and
• 26:30
  Speaker 2: you're more likely to get into car crashes. And so
• 26:33
  Speaker 2: these drugs, even though they might help with sleep, they
• 26:35
  Speaker 2: are in general not recommended for elderly patients because the
• 26:40
  Speaker 2: downsides are just too high.
• 26:42
  Speaker 1: So your one hundred year old co host here should
• 26:44
  Speaker 1: not be taken these things. No, So I always wonder
• 26:50
  Speaker 1: about how we discover these side effects. It seems like
• 26:52
  Speaker 1: we put these things out and then we discover, oh
• 26:54
  Speaker 1: my gosh, they're addictive, Oh my gosh, they're bad for
• 26:56
  Speaker 1: this population. So I guess we do some preliminary test
• 26:59
  Speaker 1: to see they're safe before we put them out there.
• 27:02
  Speaker 1: But basically we're testing them on the population without really
• 27:05
  Speaker 1: knowing the side effects.
• 27:06
  Speaker 2: Well, so this drug first became available in like the
• 27:10
  Speaker 2: nineteen fifties, Yeah, And I think we had much less
• 27:13
  Speaker 2: testing before drugs went public back then. And so yes,
• 27:17
  Speaker 2: I think that this is a drug that was released
• 27:20
  Speaker 2: to the public before we understood some of the more
• 27:23
  Speaker 2: negative side effects, and so some of them were sort
• 27:27
  Speaker 2: of observed along the way. Wow, which is less good.
• 27:30
  Speaker 2: The next drug I'm going to talk about, which is zolpitem,
• 27:33
  Speaker 2: is an example of a Z drug, A non zolpiedom.
• 27:37
  Speaker 2: Really did I pronounce it wrong?
• 27:39
  Speaker 1: I don't know, but it's a terrible name. Did they
• 27:41
  Speaker 1: come up with that name? Is that like some marketing scheme.
• 27:43
  Speaker 2: A lot of the drugs that are marketed have a
• 27:46
  Speaker 2: Z in their name, and I think that's why they're
• 27:48
  Speaker 2: called the Z drugs. And so I think someone came up.
• 27:50
  Speaker 3: With that Z.
• 27:51
  Speaker 1: I gets because it's associated with sleep, But zolpa dome
• 27:54
  Speaker 1: it just sounds like a letdown. Oh, I'm sorry, you
• 27:57
  Speaker 1: got a zolpidom.
• 27:59
  Speaker 2: Maybe it's zolpa z lpid em. I mean, we know
• 28:03
  Speaker 2: not to trust me for pronunciations.
• 28:05
  Speaker 1: Yeah, all right, so if we take this Z drug,
• 28:08
  Speaker 1: what happens?
• 28:09
  Speaker 2: Okay? Well, so it's a non benzo diazepine drug, is
• 28:12
  Speaker 2: what it's called. And these started getting synthesized in the
• 28:14
  Speaker 2: nineteen eighties. It binds to like the same kind of
• 28:18
  Speaker 2: receptor as benzodiazepines, but there's actually like a bunch of
• 28:22
  Speaker 2: different kinds of GABBA receptors, and these drugs bind to
• 28:25
  Speaker 2: like a smaller subset of the receptors and so the
• 28:28
  Speaker 2: bad effects are minimized, and so these have fewer bad effects.
• 28:35
  Speaker 2: They've got a lot of the good stuff going on.
• 28:38
  Speaker 2: And so it does seem to be associated with like
• 28:40
  Speaker 2: you fall asleep faster, you wake up less often, you
• 28:43
  Speaker 2: sleep for longer, you're less likely to be tired during
• 28:48
  Speaker 2: the day, You're less likely to have memory issues, you're
• 28:52
  Speaker 2: less likely to like fall and stuff like that. But
• 28:55
  Speaker 2: I found this review paper that was the one that
• 28:57
  Speaker 2: was saying that like, oh, you're you know, it's not
• 28:59
  Speaker 2: associated with a lot of memory issues, blah blah blah.
• 29:02
  Speaker 2: But they also said, you know, when we were reviewing
• 29:05
  Speaker 2: all of these papers, we should note that the quality
• 29:08
  Speaker 2: of most of the papers we were reviewing was pretty bad, like,
• 29:13
  Speaker 2: and so it doesn't look like there's a lot of
• 29:15
  Speaker 2: papers where you know, like good use of placebos or
• 29:18
  Speaker 2: large sample sizes and blah blah blah. And so although
• 29:22
  Speaker 2: things look like they're pointing in a good direction, we
• 29:25
  Speaker 2: haven't really collected loads of exactly the kind of data
• 29:28
  Speaker 2: that we would want to feel super confident about it.
• 29:31
  Speaker 1: So there could still be like dangerous side effects lurking
• 29:33
  Speaker 1: out there, like makes you more likely to hurt yourself
• 29:36
  Speaker 1: laughing on a podcast.
• 29:37
  Speaker 2: Could be could be yes, maybe yeah, yeah, maybe you
• 29:41
  Speaker 2: get gallstones, just like Kelly, that's yeah, weird sense of humor, Daniel. So,
• 29:49
  Speaker 2: but for this drug, you are specifically supposed to take
• 29:53
  Speaker 2: low doses for short periods of time. Nice, and so
• 29:56
  Speaker 2: there shouldn't be people out there who are taking high
• 29:59
  Speaker 2: dose for long periods of time. And so if it
• 30:01
  Speaker 2: is the case that you know, high doses for long
• 30:03
  Speaker 2: periods of time do have negative impacts, you know, that
• 30:06
  Speaker 2: shouldn't matter because people probably shouldn't be taking it in
• 30:10
  Speaker 2: that way, or at least it's not recommended.
• 30:12
  Speaker 1: All right, So we've done benzodiazepine, we've done the z drugs.
• 30:16
  Speaker 1: What about the old standby melitonein that feels like kind
• 30:20
  Speaker 1: of natural and simple in comparison?
• 30:22
  Speaker 2: Yeah, yeah, And so I started looking into this because
• 30:25
  Speaker 2: you know, for a while I was having disrupted sleep
• 30:27
  Speaker 2: and I was like, well, maybe I'll try melatone, And
• 30:29
  Speaker 2: so I dug into the literature, and I dug into
• 30:31
  Speaker 2: the literature, you know, specifically like trying to answer Thomas's
• 30:34
  Speaker 2: questions for you know, people who are older than me,
• 30:37
  Speaker 2: and it looks like the answer is. It depends, like
• 30:41
  Speaker 2: the results are super inconsistent. Really, the most consistent result
• 30:46
  Speaker 2: is that it helps you fall asleep a little faster.
• 30:49
  Speaker 2: But the studies that find that the effects size is
• 30:52
  Speaker 2: often something like five minutes. You know, like you fall
• 30:56
  Speaker 2: asleep five minutes faster, which is not a big difference.
• 30:59
  Speaker 1: I don't know. Five minutes of lying there with your
• 31:01
  Speaker 1: eyes closed trying to fall asleep can feel like a
• 31:03
  Speaker 1: thousand years.
• 31:04
  Speaker 2: Okay, all right, that you might be a good candidate
• 31:06
  Speaker 2: for melatonin. You're not supposed to use it like long term.
• 31:10
  Speaker 2: You're supposed to just kind of use it sort of
• 31:12
  Speaker 2: short term, not stand it like forever. It doesn't seem
• 31:15
  Speaker 2: to help too much with things like reducing the number
• 31:18
  Speaker 2: of times that you wake up or influencing how long
• 31:21
  Speaker 2: you sleep overall, And some studies have found that you
• 31:26
  Speaker 2: have what they call a residual daytime sedation. So like
• 31:29
  Speaker 2: you take it the night before, and then the next
• 31:31
  Speaker 2: day it's still making you a little bit tired, and
• 31:34
  Speaker 2: so you might wonder were those additional five minutes worth
• 31:36
  Speaker 2: it if the next day you're still feeling kind of sleepy. Yeah,
• 31:40
  Speaker 2: you know, you'd have to make that decision up for yourself.
• 31:42
  Speaker 2: And then there are some studies that find no effect
• 31:45
  Speaker 2: at all, Like you take the melotonein it didn't make
• 31:47
  Speaker 2: the people in the study fall asleep any faster, and
• 31:50
  Speaker 2: so you know, it's it seems to have done nothing.
• 31:53
  Speaker 1: So there's no perfect bullet out there.
• 31:55
  Speaker 2: It doesn't seem like there's any perfect bullet out there
• 31:58
  Speaker 2: that has no you know, no risks associated with it.
• 32:02
  Speaker 2: And I think, you know, that's just kind of life.
• 32:04
  Speaker 2: I think just.
• 32:05
  Speaker 1: About that's kind of biology.
• 32:07
  Speaker 2: That kind of biology, you know. I think anytime you
• 32:09
  Speaker 2: take a medication, you get a pamphlet with potential side
• 32:13
  Speaker 2: effects that you need to discuss with your doctor or
• 32:16
  Speaker 2: your pharmacist and understand the risks of There are plenty
• 32:19
  Speaker 2: of people who are on sleep aids and they feel
• 32:22
  Speaker 2: like it's worth it, that the benefits outweigh the risks.
• 32:24
  Speaker 2: But I think that you if you're having trouble sleeping,
• 32:27
  Speaker 2: you should go to your doctor and talk about why
• 32:29
  Speaker 2: you're having trouble sleeping, because you know, if the problem
• 32:32
  Speaker 2: is pain, then maybe like tailan al or tile and
• 32:35
  Speaker 2: al PM would be worth it and it would solve
• 32:38
  Speaker 2: the problem. But you know, I think it's important to
• 32:40
  Speaker 2: talk to your doctor about the specific problems you're having
• 32:43
  Speaker 2: and the you know, costs and benefits of taking drugs,
• 32:47
  Speaker 2: and you know, work through it with them.
• 32:49
  Speaker 1: It amazes me that in this day and age, when
• 32:51
  Speaker 1: we can do so much, we still don't understand sleep
• 32:54
  Speaker 1: very well, and so we don't understand how to manipulate
• 32:57
  Speaker 1: it and correct it and adjust. It's such a basic
• 33:01
  Speaker 1: part of life and still such a huge challenge and
• 33:04
  Speaker 1: a mystery.
• 33:05
  Speaker 2: But you know, with how complicated our bodies are, I
• 33:07
  Speaker 2: don't know that we should expect that there would be
• 33:10
  Speaker 2: a perfect solution, you know, Like our bodies don't necessarily
• 33:14
  Speaker 2: have like a little switch where you should just be
• 33:16
  Speaker 2: able to like push up the knob for more sleep
• 33:19
  Speaker 2: with nothing else getting messed up. Like we were just
• 33:22
  Speaker 2: an interconnected mess of things, and maybe you can't tinker
• 33:26
  Speaker 2: with one thing without messing up something else. I don't know.
• 33:29
  Speaker 2: I think I think what we've managed to do is
• 33:31
  Speaker 2: pretty amazing, and hopefully we just keep getting better.
• 33:34
  Speaker 1: That's a fascinating, in kind of depressing theory. I imagine
• 33:38
  Speaker 1: our bodies as these really complex machines with all these
• 33:40
  Speaker 1: knobs on it, and it's of course hard to predict
• 33:42
  Speaker 1: what happens if you pull this lever or press that button.
• 33:46
  Speaker 1: But I always assume that there's some place in that
• 33:49
  Speaker 1: phase space of operations where things go the way you want.
• 33:52
  Speaker 1: But it sounds like you're suggesting that, like, there may
• 33:54
  Speaker 1: be no way to tweak these knobs to get you
• 33:57
  Speaker 1: where you want to be.
• 33:59
  Speaker 2: Yeah, I'm not sure that there is always going to
• 34:01
  Speaker 2: be a way to tweak the nubs to get you
• 34:03
  Speaker 2: exactly where you want to be.
• 34:04
  Speaker 1: Wow, fascinating. That's a depressing thought, Kelly.
• 34:08
  Speaker 2: I mean, I don't know that evolution is always going
• 34:09
  Speaker 2: to be like, oh, I need to make sure there's
• 34:11
  Speaker 2: some way for Kelly to get to her optimum level
• 34:13
  Speaker 2: of sleep. You know, evolution is just you get.
• 34:16
  Speaker 1: What you get and you don't get upset and.
• 34:18
  Speaker 2: You don't get us set exactly.
• 34:40
  Speaker 1: Okay, we're back and we're answering questions from listeners. We
• 34:43
  Speaker 1: span an amazing and delicious array of topics. We've also
• 34:47
  Speaker 1: been getting notes from listeners that they're really appreciating the
• 34:50
  Speaker 1: huge variety of topics that we cover. I assume that
• 34:53
  Speaker 1: means that they're enjoying all the biological and chemical questions
• 34:56
  Speaker 1: we're tackling. So I'm very glad to have such a range.
• 34:59
  Speaker 2: I think that means that they're enjoying the questions that
• 35:01
  Speaker 2: they're submitting, which have been wonderful, and we should give
• 35:04
  Speaker 2: them the credit for the great diversity.
• 35:08
  Speaker 1: All right, And so we're going to zoom out from
• 35:09
  Speaker 1: sleep questions to think about the cosmic context, and of
• 35:13
  Speaker 1: course talk about aliens. Here's a question from Ralph which
• 35:17
  Speaker 1: sets me up to give a little rant.
• 35:19
  Speaker 6: Yay, So I've seen some sensationalist headlines recently based on
• 35:24
  Speaker 6: Harvard physicist Dabby Lobe's claim that an interstellar object moving
• 35:28
  Speaker 6: through our Solar System might be an alien spacecraft with
• 35:32
  Speaker 6: malicious intent. And I'm probably not going to lose any
• 35:35
  Speaker 6: sleep worrying about this, but it reminds me of a
• 35:38
  Speaker 6: recent podcast you guys did where you discuss the effects
• 35:40
  Speaker 6: of interstellar space travel on humans, And I'm thinking, what
• 35:43
  Speaker 6: if you shifted the perspective to aliens. You know, specifically,
• 35:47
  Speaker 6: what kinds of evolutionary characteristics might make them more adapted
• 35:52
  Speaker 6: to survive interstellar travel, and assuming they have superior understanding
• 35:57
  Speaker 6: of physics, what kinds of propulsion system might they employ?
• 36:01
  Speaker 6: This might be an opportunity for you guys to put
• 36:03
  Speaker 6: on your sci fi hats and have a little fun.
• 36:05
  Speaker 2: Thank you well, I'm glad to hear that Ralph isn't
• 36:08
  Speaker 2: planning on losing any sleep, but I am looking forward
• 36:12
  Speaker 2: to hearing Daniel's rants.
• 36:16
  Speaker 1: Apparently, not worrying about aliens is the way they get
• 36:18
  Speaker 1: a good night's sleep.
• 36:19
  Speaker 2: Oh then you don't sleep much, do you, Daniel, because
• 36:22
  Speaker 2: you spend a lot of time worrying about aliens.
• 36:25
  Speaker 1: True. So Ralph mentions this interstellar object three i at lists,
• 36:31
  Speaker 1: which recently entered our solar system. And this was a
• 36:35
  Speaker 1: lot of fun because we haven't seen very many interstellar objects.
• 36:38
  Speaker 1: We've only been looking for a few years, and we've
• 36:41
  Speaker 1: seen three of them.
• 36:42
  Speaker 3: Now.
• 36:42
  Speaker 1: That's why it's called three i at lists, and each
• 36:45
  Speaker 1: one is new because each one is like one of
• 36:47
  Speaker 1: the first few samples we've ever gotten from other solar
• 36:50
  Speaker 1: systems out there. We think these things are probably chunks
• 36:53
  Speaker 1: of rock from like the equivalent of the Orc cloud
• 36:56
  Speaker 1: around some other star which got gravitationally dislodged, and instead
• 37:00
  Speaker 1: of falling into that star and becoming a long period comet,
• 37:03
  Speaker 1: just floated through the galaxy until it ran into our
• 37:06
  Speaker 1: solar system. So it's super fascinating to get to see
• 37:09
  Speaker 1: these chunks.
• 37:10
  Speaker 2: Welcome to our solar system. I think I finally remembered
• 37:14
  Speaker 2: how to pronounce the first one. Oh muamua, right.
• 37:18
  Speaker 1: That's right, yeah, nice.
• 37:20
  Speaker 2: I think I've messed it up on the show something
• 37:21
  Speaker 2: like six or seven times, but eight times at charm.
• 37:26
  Speaker 1: You go congratulations. And so at first, of course, we
• 37:31
  Speaker 1: didn't know exactly what to expect, because every single one
• 37:34
  Speaker 1: of these is weird. They're drawn from a huge population
• 37:36
  Speaker 1: that's very diverse, and so they're all going to be
• 37:38
  Speaker 1: different from anything we've seen before, and this one was
• 37:42
  Speaker 1: no different from that. As it got closer, we saw
• 37:44
  Speaker 1: that it was unusual. It had a lot more carbon dioxide.
• 37:47
  Speaker 1: In the commentary coma, it seems to have unusual amounts
• 37:50
  Speaker 1: of nickel and cyanide.
• 37:52
  Speaker 2: Is the coma. That's just the tail, right.
• 37:55
  Speaker 1: The coma is the fuzz around the comet.
• 37:57
  Speaker 2: OK.
• 37:57
  Speaker 1: So comet is like a frozen chunk, and then as
• 37:59
  Speaker 1: a it's closer to the Sun, there's more radiation on it,
• 38:03
  Speaker 1: and as it heats up, various parts of its supplemate
• 38:05
  Speaker 1: and turn into gas, and that makes the coma and
• 38:07
  Speaker 1: then if there's more pressure from the solar wind or
• 38:11
  Speaker 1: from the radiation, that can make a tail. And when
• 38:14
  Speaker 1: it first arrived, of course, we didn't have a lot
• 38:16
  Speaker 1: of great data, and we didn't have a lot of data,
• 38:18
  Speaker 1: and so there was a lot of speculation about what
• 38:20
  Speaker 1: it might be. By now we've pointed all of our
• 38:22
  Speaker 1: best telescopes at it, we think we understand it. It
• 38:24
  Speaker 1: looks like a frozen rock from another solar system. It's velocity,
• 38:28
  Speaker 1: it's trajectory, all the emissions, it all makes sense. The
• 38:32
  Speaker 1: prosaic explanation of it being a frozen blob from another
• 38:35
  Speaker 1: solar system is a great description of this thing. But
• 38:39
  Speaker 1: before we had all of this data, there was one
• 38:42
  Speaker 1: famous astrophysicist from Harvard Auvi Loebe who made a lot
• 38:46
  Speaker 1: of hype about how it could be aliens. And so
• 38:50
  Speaker 1: you know, on the podcast, I try to generally only
• 38:52
  Speaker 1: be positive and only talk about people if I have
• 38:54
  Speaker 1: something nice to say. But this guy's made such a
• 38:57
  Speaker 1: negative impact on science and science communication that I think
• 39:00
  Speaker 1: it deserves a little bit of a comment.
• 39:02
  Speaker 2: I love that you jumping up on your soapbox and
• 39:06
  Speaker 2: getting angry is and I think it deserves a little
• 39:09
  Speaker 2: bit of a comment like this is this is angry
• 39:11
  Speaker 2: Daniel is I'm going to make a little bit of
• 39:13
  Speaker 2: a comments. Let's hear it.
• 39:15
  Speaker 3: Well.
• 39:15
  Speaker 1: The issue is that avelobe claims to be like more
• 39:18
  Speaker 1: open minded to new ideas than mainstream astronomy, and he
• 39:22
  Speaker 1: likes to paint everybody in mainstream astronomy is like closed
• 39:25
  Speaker 1: minded and rejecting the idea that it could be aliens,
• 39:29
  Speaker 1: you know, out of hand, just dismissing it. It's part
• 39:31
  Speaker 1: of this whole shtick that like academics are closed minded
• 39:35
  Speaker 1: or marched to the beat of some drummer. And you're
• 39:38
  Speaker 1: an academic, you know, you can't get to academics to
• 39:41
  Speaker 1: degree on anything. And it's like everybody's dream to disprove
• 39:44
  Speaker 1: somebody else, or to upset the narrative, or to make
• 39:47
  Speaker 1: a big paper discovering something mind blowing. And for a
• 39:51
  Speaker 1: guy from Harvard to be like complaining about mainstream astronomy, like,
• 39:55
  Speaker 1: what's more mainstream astronomy than astronomy at Harvard. But the
• 39:59
  Speaker 1: real issue is that he makes a bunch of arguments,
• 40:02
  Speaker 1: and these arguments are weak and they're flawed, and then
• 40:05
  Speaker 1: when experts criticize these things, fairly. He portrays that as
• 40:10
  Speaker 1: them trying to shut him down unfairly, when that's just
• 40:13
  Speaker 1: how the marketplace of ideas work, and if your ideas
• 40:15
  Speaker 1: can't survive in the marketplace, maybe they're wrong. But instead
• 40:18
  Speaker 1: he plays victim and he says, look, they're attacking me.
• 40:21
  Speaker 1: Oh come, And you know he's made basic mistakes, like
• 40:24
  Speaker 1: he misunderstood the difference between solar radiation pressure from photons
• 40:27
  Speaker 1: and solar wind from particles. He assumed that the fuzz
• 40:31
  Speaker 1: around the comet, which is just due to the coma,
• 40:33
  Speaker 1: was because of smearing. It was because it was moving
• 40:35
  Speaker 1: so fast. You'd understand that the telescopes were tracking the
• 40:38
  Speaker 1: comet and the show there should be no smearing effect.
• 40:42
  Speaker 1: He assumed that because this thing came in close to
• 40:44
  Speaker 1: the ecliptic, it was therefore very very unlikely to be
• 40:47
  Speaker 1: a natural object, which is silly. It's just like you know,
• 40:51
  Speaker 1: shooting a gun in a random direction and then drawing
• 40:54
  Speaker 1: a bullseye around it later and saying how unlikely that
• 40:57
  Speaker 1: the bullet landed on the bullseye. You know, you can
• 41:00
  Speaker 1: always find something unusual if you look through enough examples.
• 41:04
  Speaker 1: And there's some great work by Steve desh and Jason
• 41:07
  Speaker 1: Wright very carefully and very fairly taking his arguments apart,
• 41:11
  Speaker 1: which he then turned around into like, look, I'm being attacked,
• 41:14
  Speaker 1: so you know, I just think it's not a good
• 41:16
  Speaker 1: faith analysis, which is a shame because we should be
• 41:19
  Speaker 1: open to any good faith commentary, and I think that
• 41:22
  Speaker 1: we are, but these bad faith attacks on mainstream astronomy,
• 41:27
  Speaker 1: I don't think they're productive at all.
• 41:29
  Speaker 3: Yeah.
• 41:29
  Speaker 2: Well, and this also really frustrating because as a Harvard professor,
• 41:32
  Speaker 2: he probably could have access to like all the experts,
• 41:35
  Speaker 2: and he could be working with them on these questions
• 41:38
  Speaker 2: and like checking to make sure like is that a
• 41:41
  Speaker 2: smudge or are we tracking it, you know, through time?
• 41:44
  Speaker 2: And anyway, these mistakes don't need to be made.
• 41:47
  Speaker 1: Yeah, And I don't know what's in his heart, so
• 41:49
  Speaker 1: I can't say for sure, but he's not acting the
• 41:51
  Speaker 1: way somebody who's interested in evidence based reasoning acts. He's
• 41:54
  Speaker 1: acting more like somebody who's out for attention and spreading
• 41:58
  Speaker 1: misinformation to benefit himself sell his books. But again, I
• 42:01
  Speaker 1: don't know what's in his heart.
• 42:02
  Speaker 3: Yeah.
• 42:02
  Speaker 1: Anyway, this was not an alien ship. Unfortunately, I wanted
• 42:07
  Speaker 1: it to be an alien ship. Lots of people wanted
• 42:08
  Speaker 1: it to be an alien ship. If it was, we
• 42:10
  Speaker 1: would be very excited. Astronomers are not like anti alien
• 42:13
  Speaker 1: in any way.
• 42:14
  Speaker 2: Probably no one wanted it to be an alien ship
• 42:17
  Speaker 2: more than.
• 42:17
  Speaker 1: You, right exactly, Yeah, come on, man, come and laser
• 42:21
  Speaker 1: half the planet but tells the secrets of the universe.
• 42:24
  Speaker 1: But that was just the prologue to Ralph's question. Ralph
• 42:26
  Speaker 1: is really wondering about, well, how would aliens get here? Like,
• 42:30
  Speaker 1: if this was an alienship, how would aliens survive that
• 42:33
  Speaker 1: interstellar journey? Could they develop new techniques, could they evolve
• 42:37
  Speaker 1: in some way that makes it better? And so this
• 42:39
  Speaker 1: was a lot of fun to think about, like what
• 42:42
  Speaker 1: kind of critter could survive a thousand or ten thousand
• 42:47
  Speaker 1: year sublight journey from another solar system? So I thought
• 42:50
  Speaker 1: about the biology of space travel a little bit. So
• 42:52
  Speaker 1: can you tell me if I get anything wrong? Yeah,
• 42:55
  Speaker 1: you know, one issue is our metabolism. Right to stay alive,
• 42:59
  Speaker 1: we need oxygen, we need the right temperature, we need
• 43:01
  Speaker 1: regular food. The whole thing is a huge ordeal, right,
• 43:06
  Speaker 1: So perhaps instead of doing that, we could somehow enter
• 43:09
  Speaker 1: like a or aliens could evolve to enter like a
• 43:13
  Speaker 1: low menabolic state, you know, essentially where you just don't
• 43:16
  Speaker 1: need as much oxygen, you don't need as much food,
• 43:19
  Speaker 1: And we have examples of this like here on Earth,
• 43:21
  Speaker 1: like tartar grades can like curl up and essentially not
• 43:24
  Speaker 1: be dead and not be frozen, but just be like
• 43:26
  Speaker 1: in a very low metabolic state.
• 43:28
  Speaker 2: The Ton state. I think that's what, because we had
• 43:32
  Speaker 2: a whole episode on tartar grades and I think it
• 43:34
  Speaker 2: was called the Ton state. Yeah. And rodafers also have
• 43:37
  Speaker 2: like you know states where they can essentially like you know,
• 43:40
  Speaker 2: freeze their existence and then come back at a later time.
• 43:43
  Speaker 2: But I think of those as sort of simple creatures,
• 43:47
  Speaker 2: not the kind of creatures that could create spaceships capable
• 43:51
  Speaker 2: of interstellar travel.
• 43:53
  Speaker 1: But we have examples on Earth of more complex creatures,
• 43:56
  Speaker 1: not with as dramatic an effect, but like you know,
• 43:58
  Speaker 1: mammals hibernate their metabolism jobs, so it's certainly possible for
• 44:03
  Speaker 1: complex creatures to change their metabolism, right.
• 44:05
  Speaker 3: Yeah.
• 44:06
  Speaker 2: Not, I mean nowhere near the time scales that you
• 44:08
  Speaker 2: would need for interstellar travel, and they still need they
• 44:11
  Speaker 2: would still need their waste removed, and they would still
• 44:14
  Speaker 2: need some energy put into the system depending on the
• 44:17
  Speaker 2: time scales.
• 44:18
  Speaker 1: Wait, do bears poop in hibernation, Kelly.
• 44:21
  Speaker 2: I don't know if they poop in hibernation, but like
• 44:24
  Speaker 2: that's because hibernation is weeks or months, not generations. Uh,
• 44:29
  Speaker 2: they got to poop eventually. I can tell you that
• 44:33
  Speaker 2: as an expert, they got it poop eventually. Okay, on
• 44:38
  Speaker 2: the repre.
• 44:38
  Speaker 1: To d in biology, you're getting that's right, that's right,
• 44:44
  Speaker 1: And of course these are just examples here on Earth.
• 44:46
  Speaker 1: But you know, it suggests that maybe it might be possible,
• 44:49
  Speaker 1: in some coroner of evolutionary space for aliens to evolve
• 44:52
  Speaker 1: in such a way that allows them to change their
• 44:54
  Speaker 1: metabolism maybe more dramatically. Do you think that's impossible? I.
• 44:58
  Speaker 2: You know, I don't think it's impossible. I think that
• 45:01
  Speaker 2: we are very far away from being able to figure
• 45:05
  Speaker 2: stuff like that out for like humans, for interstellar travel.
• 45:08
  Speaker 1: Well, we can't even put humans to sleep here on
• 45:10
  Speaker 1: Earth reliably.
• 45:11
  Speaker 2: So yeah, yeah, that's right, that's right.
• 45:13
  Speaker 3: I don't know.
• 45:13
  Speaker 2: I guess I'm fifty to fifty on whether or not
• 45:15
  Speaker 2: that's going to be impossible for humans.
• 45:17
  Speaker 1: But you know, imagine aliens and for some reason they've
• 45:20
  Speaker 1: gone out into space and so there's evolutionary advantages to
• 45:23
  Speaker 1: being able to survive, you know, to the difference between
• 45:26
  Speaker 1: being alive and being dead, requiring very very small requirements,
• 45:31
  Speaker 1: small amount of foods, small amount of oxygen, et cetera,
• 45:33
  Speaker 1: maybe lower temperatures. It seems like perhaps evolution could cook
• 45:38
  Speaker 1: up some way to survive that situation.
• 45:40
  Speaker 2: Now, well, so you know, good frogs in like Michigan
• 45:44
  Speaker 2: can freeze and then thaw out, and so you know,
• 45:48
  Speaker 2: I think there you can like freeze organisms. But I
• 45:50
  Speaker 2: also think that it is the case that there's some
• 45:52
  Speaker 2: percent that die when the thought out happens. I hate
• 45:56
  Speaker 2: to reference science fiction as though it's science fact, but
• 45:59
  Speaker 2: I think in Andy Weir's book Hail Mary, some of
• 46:02
  Speaker 2: the crew did not survive the thaw out. This is
• 46:05
  Speaker 2: kind of a spoiler, but not really. It happens pretty
• 46:07
  Speaker 2: early on. But like, you know, I imagine that a
• 46:10
  Speaker 2: lot of the procedures that we would come up with
• 46:13
  Speaker 2: would have a like less than one hundred percent success rate.
• 46:17
  Speaker 2: But but yeah, we might be able to come up
• 46:19
  Speaker 2: with some situation. But you know, I don't know if
• 46:22
  Speaker 2: referencing natural selection is going to help us much because
• 46:25
  Speaker 2: we are a species that has not been exposed to
• 46:28
  Speaker 2: extreme temperatures for a long time, you know, and exposed
• 46:31
  Speaker 2: to natural selection associated with that. So you know, we
• 46:36
  Speaker 2: don't survive freezing. That's not a thing we do usually.
• 46:40
  Speaker 1: All right. So the next kind of adaptation that aliens
• 46:43
  Speaker 1: might potentially evolve would have to do with radiation. Right
• 46:47
  Speaker 1: out in space, it's not just empty space. There's lots
• 46:50
  Speaker 1: of particles out there. They're moving at very high speeds.
• 46:53
  Speaker 1: Even if you're just on the Moon, which is not
• 46:55
  Speaker 1: very far away, you're going to be exposed to high
• 46:58
  Speaker 1: energy particles. This is rady. They're gonna zip through your body,
• 47:01
  Speaker 1: they're gonna tear up your DNA, They're gonna do lots
• 47:03
  Speaker 1: of damage. And this is why we like being here
• 47:06
  Speaker 1: on Earth under our magnetic shield and our atmosphere, which
• 47:09
  Speaker 1: protects us from a lot of that radiation. And anytime
• 47:12
  Speaker 1: we go into space we need to worry about it.
• 47:14
  Speaker 1: So if aliens are traveling here from another star, they're
• 47:17
  Speaker 1: gonna have to worry about radiation. The best way to
• 47:20
  Speaker 1: protect yourself from radiation is mass have like huge water
• 47:24
  Speaker 1: tanks or huge amounts of lead or something, some high
• 47:27
  Speaker 1: Z material between you and the radiation. Is gonna absorb
• 47:31
  Speaker 1: a lot of that. But mass is tough, right, because
• 47:34
  Speaker 1: the more mass of your ship, the harder it is
• 47:36
  Speaker 1: to accelerate up to some reasonable speed. You can imagine
• 47:39
  Speaker 1: like finding an asteroid and hollowing it out and living
• 47:42
  Speaker 1: on the inside while you travel from one start to
• 47:44
  Speaker 1: the other. But asteroids are massive, and it takes a
• 47:47
  Speaker 1: lot of energy to get an asteroid up to near
• 47:50
  Speaker 1: the speed of light. So instead of building some technology,
• 47:53
  Speaker 1: you might imagine aliens evolving some biological mechanisms, you know,
• 47:58
  Speaker 1: like more active repair systems, or redundant genetic coding or
• 48:03
  Speaker 1: something like that, or maybe even some sort of non
• 48:06
  Speaker 1: DNA based way to store genetic information that's more robust
• 48:10
  Speaker 1: to radiation.
• 48:11
  Speaker 2: I mean, do you think that three I at lasts
• 48:15
  Speaker 2: is big enough that something could be living inside there
• 48:17
  Speaker 2: and be shielded from radiation.
• 48:22
  Speaker 1: I think I've read that post by AVI already speculating that.
• 48:29
  Speaker 3: Yeah.
• 48:30
  Speaker 1: Absolutely. I mean it's like, I think, a few kilometers across,
• 48:33
  Speaker 1: So that's definitely big enough to be a nice ship
• 48:35
  Speaker 1: for sure.
• 48:36
  Speaker 2: Okay, Yeah, I still doubt it though, all.
• 48:38
  Speaker 1: Right, Yeah, but I'd love to go inside and take
• 48:40
  Speaker 1: a look.
• 48:41
  Speaker 2: Yeah, beat me up.
• 48:42
  Speaker 1: These are maybe ways you could evolve biological techniques to
• 48:45
  Speaker 1: survive the high radiation in space, but again this is
• 48:49
  Speaker 1: just science fiction speculation. And then another issue which Kelly
• 48:52
  Speaker 1: has mentioned many times about living in space is a
• 48:55
  Speaker 1: question of like how do you reproduce?
• 48:57
  Speaker 2: You know, It's not like I'm fixated on that, Daniel,
• 48:59
  Speaker 2: You make it sound like it's all I ever talk about.
• 49:03
  Speaker 1: You know, is it possible for your species to reproduce
• 49:06
  Speaker 1: and to have gestation and development and all that stuff
• 49:10
  Speaker 1: in space? I think it's certainly possible for another species
• 49:14
  Speaker 1: to evolve the capacity or to already have a system which,
• 49:18
  Speaker 1: by chance is not sensitive to gravity. And I think
• 49:21
  Speaker 1: we don't know whether ours is or how sensitive ours is.
• 49:25
  Speaker 1: But if you wanted to avoid that entirely, you can
• 49:28
  Speaker 1: imagine another way to spread your aliens around the galaxy
• 49:32
  Speaker 1: is not to send adults, but to send some sort
• 49:34
  Speaker 1: of like precursor you know, basically gam meats, and then
• 49:38
  Speaker 1: have them be created when they arrive and maybe raised
• 49:42
  Speaker 1: by robots, you know, chat GPT raised. I've read that
• 49:45
  Speaker 1: story for sure. It's a common theme in science fiction,
• 49:48
  Speaker 1: and in this sense, if you do that, then like
• 49:50
  Speaker 1: maybe travel is sort of part of your reproductive system.
• 49:53
  Speaker 1: You know, you have your cozy evening, you create your
• 49:56
  Speaker 1: gam meats, you put them on a ship, you send
• 49:57
  Speaker 1: them off, and you never meet your kids. They'd never
• 50:00
  Speaker 1: jump on your head at two in the morning, and
• 50:01
  Speaker 1: maybe you sleep better.
• 50:02
  Speaker 2: Oh yeah, and then you don't get all the diseases
• 50:04
  Speaker 2: they bring home from kindergarten. And all right, I'm in
• 50:08
  Speaker 2: I'm just kidding. That would really bum me out.
• 50:12
  Speaker 1: But that would be really weird as the visit teas. Right,
• 50:15
  Speaker 1: if visitors arrived and they're basically alien babies and we
• 50:19
  Speaker 1: just watched them grow up, and they've never experienced their
• 50:21
  Speaker 1: home planet either, I don't know. It sounds like a
• 50:23
  Speaker 1: fun science fiction story.
• 50:24
  Speaker 2: It does. But presumably the robots that are bringing them up, would,
• 50:28
  Speaker 2: you know, have a bunch of knowledge about the home planet,
• 50:30
  Speaker 2: and it would be able to teach you a bunch
• 50:32
  Speaker 2: of stuff.
• 50:33
  Speaker 1: In which case the robots are the real visitors, right,
• 50:35
  Speaker 1: those are the ones we'd want to talk to.
• 50:36
  Speaker 2: Yeah, yeah, forget the kids.
• 50:39
  Speaker 1: And then from a technological point of view, let's assume
• 50:42
  Speaker 1: that aliens don't have warp drives, they don't have wormholes,
• 50:45
  Speaker 1: otherwise they could just get here in a moment. There
• 50:48
  Speaker 1: are ways to get from star to star in a
• 50:50
  Speaker 1: reasonable amount of time if you use things like light sales.
• 50:53
  Speaker 1: This helps you avoid having to carry your fuel with
• 50:56
  Speaker 1: you because you just have like a huge reflective sheet
• 50:59
  Speaker 1: and you shine on it. It zooms it up to
• 51:01
  Speaker 1: near the speed of light much more quickly because it's
• 51:04
  Speaker 1: not so massive. This doesn't work for an asteroid very well,
• 51:07
  Speaker 1: but it works for a small payload, and you can
• 51:09
  Speaker 1: cruise between the stars and trying to use the arriving
• 51:12
  Speaker 1: star as a break when you arrive, and you can
• 51:16
  Speaker 1: maybe even have like a magnetic tail that you can
• 51:18
  Speaker 1: use to steer. So this is technologically totally feasible. I
• 51:22
  Speaker 1: can imagine us doing this. I mean, we're still talking
• 51:25
  Speaker 1: huge time periods to visit the star, but it's technologically
• 51:29
  Speaker 1: not impossible.
• 51:30
  Speaker 2: I'm staying here.
• 51:33
  Speaker 1: More exotically, Aliens might show up with their whole solar system.
• 51:37
  Speaker 1: You know. Elon Musk talks about building a dice in
• 51:40
  Speaker 1: sphere to capture all the energy of the Sun. But
• 51:42
  Speaker 1: if instead you build half a dice in sphere, like
• 51:45
  Speaker 1: a mirror that wraps around half of the Sun, and
• 51:48
  Speaker 1: then you make it gravitationally captured by the Sun. Then
• 51:51
  Speaker 1: in effect it's an engine because half the light gets
• 51:54
  Speaker 1: reflected back and half of a dozen and so there's
• 51:57
  Speaker 1: a net momentum there and basically it just drags the
• 51:59
  Speaker 1: whole solar them so you never have to leave your planet.
• 52:02
  Speaker 1: Kelly can stay under the covers and we can go
• 52:05
  Speaker 1: visit aliens, or aliens could do that and come visit us.
• 52:08
  Speaker 2: Yay, that sounds wonderful.
• 52:11
  Speaker 1: All right, So those are some of the ideas I
• 52:13
  Speaker 1: have for how aliens might come and possess. I hope
• 52:16
  Speaker 1: that happens one day, and when it does, I'm sure
• 52:18
  Speaker 1: that the astronomy community is going to be very interested
• 52:21
  Speaker 1: and totally open minded to the possibilities.
• 52:24
  Speaker 2: All right, Well, let's see what Ralph had to say
• 52:26
  Speaker 2: about Daniel's rant and your answer.
• 52:29
  Speaker 6: Guys, thanks for answering my question. Some very interesting thoughts
• 52:32
  Speaker 6: and ideas there. I'm happy that I gave Daniel a
• 52:35
  Speaker 6: chance to rant, and I'm pretty impressed about how quickly
• 52:39
  Speaker 6: Kelly was able to work in an alien poop reference.
• 52:48
  Speaker 1: All right, thank you very much everybody for sending us
• 52:50
  Speaker 1: your questions. It's really my favorite thing to see your
• 52:53
  Speaker 1: questions in my inbox. And I love answering them here
• 52:56
  Speaker 1: on the pod. If you have questions, please don't be shy.
• 52:58
  Speaker 1: We love, love, love to hear you.
• 53:00
  Speaker 2: Yes, send your questions to questions at Daniel and Kelly
• 53:03
  Speaker 2: dot org. We answer them as soon as we can
• 53:05
  Speaker 2: and we answer all the questions, and some of the
• 53:07
  Speaker 2: questions also end up on the show.
• 53:09
  Speaker 1: Have a great day everyone, Hope you sleep well.