July 14, 2020 • 42 mins
Can gravity waves kill you? Why do we have particles? Can fission power a star?
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Speaker 1 (00:08):
Hey, Daniel, how's our email inbox looking these days? Oh? Man,
like usual, it is jammed full. We have a big
pile of questions. Really, people still have questions. You thought
maybe we'd like answered all the questions in the interview. Well,
we have done about two episodes and ten listener question episode.
I figured, you know, eventually people might be satisfied and
know all the answers to the universe. I think that
(00:30):
the more we answer people's questions, the more questions they have.
Man sciences like that, isn't it always teasing you with
an answer and then dropping more questions? And thank goodness,
otherwise we would run out of episodes and then we
wouldn't be here. Hi am more handmaker, tunist and the
(01:00):
creator of PhD comics. Hi. I'm Daniel. I'm a particle
physicist and I'm a professional email question answer. Wow. Really
you get paid for that? I just feel like a
professional what I'm doing it. I feel like that's what
I have to do to get paid, which I don't
do very well, but which probably explains a lot. But
sometimes people write into the podcast and I think this
might be the only time this person has asked the
(01:22):
question to a physicist and gone an answer. So I
feel a little bit like I'm representing physics in some way. Wow,
you're the ambassador of the physics nation a little bit. Yeah,
So I feel some responsibility to know, be polite and
funny and insightful and all that stuff. You know. It's
like that first day of class in college. Sometimes I
get to teach freshman and I am on the first Monday,
(01:43):
and I feel like, Wow, I am college for them.
So there's a bit of pressure there. Yeah, and if
someone walks out, you're like, well, I guess I failed physics.
Nobody walks out on my emails fortunately, But anyways, welcome
to our podcast. Daniel and Jorge explained the Universe but
suction of I Heart Radio, in which we tackle all
the questions in the universe, all the things that science
(02:05):
wants to know and all the things that everybody wants
to know. How did the universe begin, what is it
made out of? How is it going to end? Why
are we all here? And should you eat your bananas
when they're black or green? That's right, it's a very
important physics question. What can kill me out there? Daniel?
And how? And when? Basically everything can kill you out
there if you're creative about it. Love, Love can't kill you, Daniel.
(02:27):
Have you seen Titanic? Soh, alright, love can kill Leonardo
to keep you but exactly anyways, Yeah, it's our podcast
where we talk about the universe and all the amazing
things in it, and we also talk about the questions
that not only scientists and physicists have at the cutting
edge of knowledge and research, but also the questions that
everyday people have about how things work and why things
(02:49):
are the way they are. That's right, because questions belong
to everybody, and asking questions is part of being human.
It's impossible to be a conscious being in this world
and I'll look around you and wonder why things are
the way they are, why they aren't different, and what
it means about the way the universe works. And scientists
are just like that. They're just people who have answered
more of their questions so far, and they're onto the
(03:10):
most interesting cutting edge questions. And so our goal today
is to bring you up to speed, to introduce you
to the forefront of knowledge and tell you all about
the questions that scientists are asking. And it turns out
the scientists are asking a lot of the same questions
that you are. It's right. Are you trying to tell
me not to look to scientists for answers, Daniel, I
just look to them for more questions. I'm trying to
(03:31):
tell you that we're all scientists, were all asking these
deep questions about the universe, and we'd all like to
know the answer. Great. So to be on the program,
we'll be doing another one of our famous listener question
episodes where we answer questions from listeners. So to be
on the podcast, we'll be tackling listener questions number eleven eleven. No,
(03:54):
we've answered a lot of these and we have a
big pile left, So if you've submitted your question and
haven't gotten answer yet, stay tuned. We're getting to them.
We love these listener Questions episodes, and I always love
these episodes because people sending the most interesting questions. These
are the really fun ones. People writing questions all the
time the email, and sometimes I'll fire off a quick answer,
but if it's a really good, juicy question that I
(04:15):
think a lot of people would like to hear the
answer to, or Brinkley, I need a little bit of
time to research, and then we'll do it on the
podcast cool. So today we have three pretty cool questions
from listeners from all over the world, and they have
to do with gravitational waves about the nature of matter
and whether or not you can have a different kind
(04:36):
of star than the ones that we are used to.
So let's jump right into it, Daniel, and let's start.
But this first question from Henrik Sumberg from Sweden, who
asks can a gravitational wave kill you? Or what will
you feel when you're close to a wave like the
one that was found by Ligo. Wow? What an awesome
(04:56):
question and a little terrifying. You know, do we thought
about gravitation with dying from gravitational waves which I just
assume we're rolling through us, but apparently they can kill us?
Can they kill us? Because that's a question? Well, it
is a great question. You know. These things are ripples
in space itself, and it's cool that we build observatories
that can spot them. But the ones that we've seen
(05:18):
so far are really far away, so it's a totally
valid question to ask what would happen if you got
close to it? I guess it's kind of like asking, like,
can of an ocean wave kill you? Right? I suppose?
I mean ocean waves certainly can kill you. I think
it's more like asking, you know, can the sun kill you?
And the answer is basically the same as from a
great distance, the sun will just make it nice and toasty,
(05:38):
but if you get too close to almost anything, it'll shrick. Well,
let's maybe recap for people who don't know. So gravitational
wave is like a wave with like a ripple in
spacetime itself. That's right. And the idea is that gravitational
information doesn't move instantly, like if the Sun disappeared, we
would still feel it's gravity for the eight minutes it
(06:00):
look for that information to get to us, because gravitational
fields ripple, right, you delete something from the universe, then
the information propagates out the field itself ripples. Right, It's
not instantaneous because nothing instantaneous in the universe exactly, nothing
is instantaneous. No information can move faster than the speed
of light. And so gravitational waves are when you have
(06:22):
really strong, very powerful objects that are accelerating around each other,
so they're making waves in space itself. Remember, gravity is
just the bending of space. You put the Sun in
the center of the Solar system, it bends the space
around it, so that the Earth's most natural path is
one to move in a circle around the Sun. And
so when you move masses around, when you accelerate them
(06:44):
back and forth around each other, it makes these waves
in space. And that's what gravitational waves are there, like
the contracting or the pulling on space itself. It's it's
really kind of bonkers, like the changes in the gravitational field.
Kind of Yeah, you can think about it two different ways.
If you like to think of space is flat and
having gravitational fields in it, then you can think of
(07:05):
it as the rippling of those gravitational fields in space.
But if you like to think about it like Einstein did,
then you know there is no gravity. There's just sort
of changes in the shape of space. And from that perspective,
gravitational waves are ripples in the shape of space, like
things get closer and then further apart, and closer and
further apart. That's what happens when a gravitational wave passes
(07:26):
you by, And I guess that we're like a wash
in gravitational waves. Like if I move my arm around
in a circle, I'm creating gravitational waves. But they're just
so small that nobody can notice. That's right. Just like
there's gravity between you and your arm, and you and
that box in front of you, and you and that banana,
you just can't feel it because gravity is just so weak.
(07:47):
Anytime an object with mass moves and accelerates, it generates
a gravitational wave, but because gravity is so weak, you
usually just can't sense it. We can only sense gravitational
waves from really really big thing things, really massive things,
precisely because gravity is so weak. It's almost kind of
like we're all swimming in like a thick Google or
(08:07):
something like if space was a Google and we're all
swimming in it. You know, any motion that I make,
or any motion that any planet makes will sort of
generate a little ripple in that Google. Yeah, precisely, And
we are listening for those ripples, and we've been listening
for them for a few decades and recently, just a
few years ago, they actually detected these ripples. As an
incredible story because people had thought these ripples existed for
(08:29):
a long long time, but they thought it might be
impossible to detect them because they are so small, because
they're so faint, because gravity is so weirdly weak. And
they had to build a really powerful device it's called
a laser interferometer with two long arms on it that
measures the length of these like kilometer long arms to
(08:50):
see if they shrink a tiny bit like the width
of a proton. So it's a really really difficult measurement
to make because these gravitational waves are very very subtle, right,
because you know, like if I shake my fist, I'm
generating ways. But there's probably no way that anything that
we have could possibly measure that. Right. Probably you need
like these giant machines just to measure that the big
ones coming from space, that's right. But you know, I
(09:12):
thought for a long time even the big ones coming
from space would be impossible. What I was a grad
student thinking about what field of physics to work, and
I considered going to cal Tech and working on the
gravitational wave system. But I remember thinking, of these guys
are never going to spot out, and they're gonna be
working forever and never see it. And hey, I was wrong,
and I'm glad they've been proven wrong. They found something
(09:33):
amazing about the universe and won themselves a Nobel Prize along.
So what you think is impossible today might be totally
routine in twenty years. You never missed that on that rate?
Did it? Didn't get to surf all the way to Sweden.
You didn't catch the wave. Yea. And we could have
met at cal Tech? Isn't that weird? Yeah, that's imagine
an alternate reality where you did go working Lego and
then we somehow met there. Yeah, but then we would
(09:55):
have met in person, and we probably wouldn't have gotten along,
probably wouldn't have started working to go there anyway. So
there are gravitational waves all around you, but only really
massive objects create gravitational waves that we can detect, right,
And that's what we measure with Lego. We measure waves
that are coming from space from really crazy events. And
so I guess Henrick's question is can one of these
(10:16):
waves kill you? Like, if you're standing there and a
big wave comes through you, is it gonna affect you
or could you even feel it? Because you know, if
it's bending and stretching space, would in all my particles
still still stay together? Yeah, in principle, these things do
have an effect on you also, right, you do get
bent and stretched when gravitational waves go through you, the
ones that hit Earth they affect things that are a
(10:38):
kilometer long by about the size of a proton, so
the effect on you is totally negligible. You can't feel them.
But these are black holes that are like one point
three billion light years away, And one of the reasons
why they're so faint is because the black holes are
so far away. So it's reasonable to ask, like, if
it was closer, if there was black holes colliding nearby,
(11:00):
making big gravitational waves closer, what would be the effect
on your body? And it's certainly true that it would
pull and push you as well. Wow, yeah, because I
guess like if you're really far away from an explosion
or something, then you don't feel the effects very much
because like you might feel a little bit of the
wind or the air kind of hitting on you, but
(11:20):
you wouldn't necessarily be hurt. But like, what if you're
right next to the explosion, that would be bad news.
Absolutely it would be bad news. And the closer you
get to these things, the more powerful they are. The
thing is, though, gravitational waves never really that powerful. Like
take one of these events, these black holes that at
one point three billion light years away, the wave is
really really weak over here. It's one part in ten
(11:43):
to the twenty one. So that means that if something
is like ten to the twenty one long, then it
shrinks by one. Now ten is predunculously big, right, which
is why these things are so hard to see. So
bring yourself closer, right, say you get, for example, just
one light year away from these black holes, and just
to paint a picture, lego measures like spinning black holes,
(12:04):
like black holes that are collapsing into each other, and
so they're it's like the death sworld of two black holes. Yeah,
because to make gravitational waves, you can't just have static mass.
That doesn't make a wave. You need stuff that's accelerating.
And so these black holes that are swirling around each other,
attracting each other, spinning in to their eventual collision, there
are great opportunities to see gravitational waves because there's huge
(12:25):
amounts of mass and there's a lot of acceleration because
they're spinning around each other. So now we're talking about
being one point three light years from two black holes gliding,
and you're saying this is where it starts to get dangerous. Well,
it doesn't actually get dangerous from the gravitational wave point
of view because the power of that is like still
one part intended the twelve, you know, so like if
you brought the whole earth within a light year of
(12:48):
these black holes, then the whole earth would shrink by
like a hundreds of a millimeter, and one part in
tend of the twelve is very small whole earth. So
would that affect me? Like, it doesn't sound like it would,
but I don't know, like maybe we'll scramble all of
my atoms or something. No. One, one hundreds of a
millimeter full of the whole earth is unmeasurably small just
for you, right, so you wouldn't even notice it. It
(13:10):
would be very difficult for you to notice. It could
break up molecules or something at that level. Molecules, you know,
because you're if you're stretching molecules. Molecules are pretty small.
Molecules are pretty small, but they're pretty tough. You know.
They're basically held together by these little bonds which are
like springs. And so it's like if somebody came and
tugged on you with a force, you know, enough to
pull you by one dred of a millimeter, you would
(13:33):
pretty much survive that, right, it's like it's a very
gentle tug on the entire earth, right, so even just
on you, it would be almost imperceptible. All right, So
it's still pretty save with a light ear. What if
I get closer, Yes, if you get within like you know,
ten thousand kilometers of the center of this black hole,
then we're talking about gravitational waves that are now serious.
(13:54):
They're like one part in the thousand. Like I would
shrink and contract by you know, a couple of millimeter,
couple of millimeters. Yeah, and so again I think you
would survive that. Like, really, you shrink and contract more
than that every day just walking around. Your height changes
more than a millimeter because of the compression on your
spine from walking around. I don't know. Maybe you never
get up from your chair so you don't drink as
(14:15):
much as other people. But somethings I laid down in
my chair and there's some stretching going on. Well that's
good for your back and for your height. But you know,
your height changes by a lot more than that just
during the day. So I don't think I would have
any effect on your health. But I see we're pretty
squishy again, We're pretty squishy. But you know, say, for example,
you're in a space suit, having your space suit get
pulled by one part in a thousand, you know that
(14:35):
could like crack the glass or break something important, or
if you're in a space ship, you know, maybe the
electronics are sensitive. So I wouldn't recommend. What about my bones?
Could my bones take it? Yeah? Your bones could take it,
for sure. I mean one part in a thousand is
not very much your bones, even though they feel pretty tough,
there's some spring to them. You're talking really close in
thousand kilometers from the center of a black hole is
(14:58):
like you're like right there, it's very us and you're
not even going to survive getting that close, Like you're
going to be torn apart by the gravitational forces that
exist just from the black holes, well before the gravitational
waves do anything to you. Really, Yeah, because remember near
a black hole, the gravitational forces, just the static ones,
(15:18):
not the changing ones, not the ripples in the gravitational field,
just the field itself is really really strong. And the
closer you are to the black hole, the stronger the forces.
So if your toes are closer than your head, then
there's a stronger force on your toes, and there is
on your head, which is the same thing as the
black hole pulling you apart. So if those forces that's
called tidal forces, the force on your head and your
(15:40):
toes is very different, then you get yanked apart. And
you don't have to be very close to a black
hole before those forces start to be larger than your
body can take. So most likely the waves won't kill you.
It will be something else. That's right. The shredded pieces
of your body that survived that close to the black
hole will not be damaged very much by the gravitational wave.
(16:01):
You'll already be torn apart alright. So then I guess
answer for Henrik is no, like a gravitation a wave
can't really kill you because if if there's anything causing
a gravitational wave that big, then it's probably gonna kill
you in some other way. That's right, exactly. So if
gravitational waves get big enough to do any damage, you're
(16:22):
probably already dead. All right. Well, I feel a lot better.
I was getting kind of concerned there. I was like,
it's something else I have to worry about. No, just
avoid black holes is good general advice. Stay at least
ten thousand kilometers from them. If not more, somebody should
put up signs or something caution universe singularity ahead. All right, well, Henry,
(16:45):
I hope that answered your question, and I hope you
can sleep a little better at night knowing that gravitational
waves can't really kill you. Maybe those gravitational waves will
be get rocking him to sleep, sleep to the sound
of the universe. All right, Well, let's get into some
of these other questions about the nature of matter and
alternate stars. But first let's take a quick break. All right,
(17:16):
we're back answering questions from listeners. Which are the best questions?
And I have to say, Daniel, these questions we got
today are pretty intense. I feel like usually people ask
sort of like funny situations or you know, more basic things,
but these are like intense, like can a gravitational wave
kill you? And making me question the nature of matter? Well,
(17:37):
we are living in strange times and everybody's at home
thinking deep thoughts. I guess. All right, Well, the next
question we have for today comes from one Ignacio Vadagas,
and he didn't say where he's from, so we're just
going to assume Jupiter. Maybe he emailed as um, you know,
fourteen years ago and he only just got the email.
All right, Well, here's what one wanted to know. I
(17:57):
was just wondering whether we have any idea yes, as
to why there is mutter, what causes energy to be
sequestered in what we call particles? Well that is deep
stuff that is deep, Like why are we here? He's
basically asking. Yeah, there's a lot of possible angles to
this question. I really wish I could chat with one
and figure out, like what is he asking? Is he
(18:18):
asking like why do we have matter or not just radiation?
Or why is there matter or not antimatter? Or why
is there something rather than nothing? Or why is energy
sort of clumped together into particles? Or there's a lot
of really fun angles. You want to ask him questions
about his question. I want to make sure we're answering
the like deep deep curiosity that's wormed its way into
(18:40):
his brain. I want to make sure that we are
We're going to touch on the question he really wants answered. Well,
it's it sounds like a pretty interesting question. I guess
he's asking, we have the universe and when we know
about energy, but why do we have matter? Like why
does matter exist in the universe, Like why the energy
suddenly decide to, you know, form into little particles of matter. Yeah,
(19:02):
that is a great question, and you know, the short
answer is, we really just don't know. But how much
we don't know sort of depends on what you think
is the most basic element of the universe, you no,
Like we have talked on this podcast before that sort
of historically we discovered that things are made out of particles.
(19:25):
You know, that all the stuff around you can be
broken up into smaller pieces, and those pieces can be
broken up into smaller pieces, and those can be broken
up in the even smaller pieces, and it gives you
the sense sort of that like particles are the basic
unit of the universe, that everything is made out of particles, right,
And the way particles interact is through these things called fields.
So that's sort of historically the way our understanding the
(19:48):
universe was developed. But more recently we have sort of
a new view on what the basic element of the
universe is, and that suggests that particles are not really
the building block of the universe of matter itself, but
that the deepest thing are actually the field. Wait, aren't
they the same thing? Like isn't a particle like what
they call an excitation of that field or like a
(20:09):
blip in the field. Yeah, Well, this new view says
exactly that that particles are just a weird state of
a field. But that says that the fields are the
deepest thing. You know. The particles aren't the fundamental building blocks.
They're just like a configuration of the fields. It's like,
you know, what's more fundamental, your hand or a fist.
Your fist is just your arrangement of your fingers in
(20:29):
a certain way, or like what's more fundamental a wave
or the ocean? Yeah, precisely. And so the fields are
the ocean, and the particles are the waves in that ocean.
And so more modern view is that everything in the
universe is filled with fields. We have an electromagnetic field,
and the waves in that field are photons. We even
have an electron field. It's different from the electromagnetic field.
(20:52):
Waves in the electron field are electrons. And then every
particle that we're familiar with has a field, and those
particles are just wiggles in those fields, like little ripples,
like a little echo or a little blip, yeah, like
a little packet. And then it's a really interesting and
fun question to ask, like, well, why do those fields
have packets? Right? One of those fields just sort of
(21:13):
slash around and have energy everywhere. I think this is
sort of what he was asking, like why is energy
clustered together into these little blip called part of where
did those blips come from? Yeah? And why do we
have blips and not just you know, blushes or squishes
or squashes or whatever, because then we wouldn't be here
to answer it's a question. Yeah, And so you know,
(21:33):
the first the deepest answers, we really just don't know.
But we have sort of two suggestions maybe sort of
directions of thought or people sort of you know, groping
in the dark towards ideas. And one is that these
fields are not just fields, their quantum fields. These fields
can't just have any particular value. They seem to have
(21:54):
certain discrete set of states that they can take, you know,
then go up one unit of energy or two two
units of energy, but not one point three seven nine. Oh,
I see, they like um. They're kind of fuzzy. You
can move this field in like half of up wave. Yeah, exactly.
And we associate these quantum units with particles. Like when
the field gets one more unit of energy that that
(22:16):
field can absorb, we consider that one more particle. And
in quantum mechanics we actually do the math. We call
these things counting operators. We like create new particles, destroyed particles.
That's how you put energy into the field. So one
way to think about it is that that a particle
is just like a quantized unit of energy in the field.
I guess maybe is it kind of like if you
(22:36):
throw a whole bunch of water into the air, Like
water tends to, you know, kind of clump into droplets,
you know, it doesn't just kind of spread out when
you throw it up into the air. Yeah, it certainly does.
I'm not sure if that's because it's quantized or there's
surface tension, or surface tension leads a quantization. That's actually
really cool thought there probably is a connection there. But
that's kind of the idea is that it tends to cluster,
(22:58):
or it tends to like little bit tends to clump
into little bits. And the second idea, which is connected
is that we've noticed that there are some symmetries to
these fields, Like these fields don't just do anything, you know,
they have rules that they follow, like the field follows
the same rules over here as they do in another
part of the universe. Or if you spin yourself in
(23:19):
the field, it follows the same rules as if you
hadn't spun yourself. So they're these symmetries, translational and rotational
symmetries to the fields themselves, right, And this is going
to sound like a really weak and fuzzy argument, but
essentially a particle is the simplest thing that can exist
in those fields that satisfies those symmetries. Like that's how
(23:41):
you explain why it forms into particles. Well, there's this
feeling and quantum mechanics that sort of everything that can
happen does happen. So if it's not explicitly forbidden by
some rule, then you will see it happen eventually. And
so particles are sort of like the simplest thing that
can exist that isn't ruled out by some basic symmetry
(24:03):
or conservation rule or whatever. So therefore they do exist.
Now that's a pretty weak argument because there's lots of
times that we expected something to exist, like a new
particle or whatever, we don't see it exists, and so
we say, well, therefore there must be some new rule
that eliminates it, and we just add that rule to
the list. So, you know, it's not like a lot
(24:23):
of these rules have deep understanding them. Some of them do.
Some of them come out of like really beautiful symmetries
of nature, etcetera. But some of them seem a little
ad hoc. So it's a totally valid open question sort
of at the edge of physics and philosophy, like why
do these particles exist? Why do we have any particles
at all? Why do the conservation laws allow for these particles?
(24:44):
Why not something else bigger and squishier. Maybe a way
to interpret his question is like, could you have a
universe without particles? Could the universe just kind of could
there be a version of this universe where no particles
ever formed and everything is just kind of like the
fields are just totally on blipped where this fields are
sitting there. You know, there are some other configurations of fields,
but you know, those universes would not lead to people
(25:06):
asking questions about those particles and those podcasts. So it's
possible those universes could exist, but they wouldn't be as
interesting or as rich, and so they wouldn't be in
them asking this question. So this sort of this selection
effect that we only tend to ask these questions in
universes where there are interesting things happening. But we already
we have ideas for like other ways you could arrange
(25:28):
quantum fields that are not particles, these things called like squirmons,
that are not the same kind of clusters of energy
in the quantum fields, but in fact are these like
we're not these other stable configurations of quantum fields that
are not quite particles. They don't act the same way. Interesting.
I guess maybe the answer you tell me is that
you know, in quantum physics it's all kind of like statistical,
(25:52):
and so if a field can kind of form into
a particle, it probably will. It probably will. Yeah, particles
will just spontaneously occur, and probably especially if you have
like energy, right, if you like, if there's energy around,
those particles are going to pop up. And that's where
we come from. And I would say that like probably
half of the theorists out there, the people who think
really deeply about quantum theory thinking that way. They think
(26:14):
the fields are the basic thing, and the particles are
like manifestations of those fields. But you know, the other
half of the community thinks about it the other way.
They think, no, no, no, the basic thing in the
universe are particles and fields. Those are just you know,
virtual particles. So this is just how particles talk to
each other. They think of the fields as you know,
(26:36):
just like a huge swarm of very briefly living particles,
because the particles are the things we interact with, right,
The fields are a little bit more abstract. The particles
are the things that we like, we can see, we
can detect, we're made of them. So there's a bunch
of people out there that think that particles are the
basic element of the universe and not the fields. Like
if you didn't have particles, you wouldn't have fields. Yeah, yeah, precisely.
(26:59):
And and if you ask those people like well why
are their particles, well, you know, they have no idea
because they just start from the particles, just because that's
the aw just because it's like asking the other half like, well,
why are their fields? You're telling me particles are made
of fields, great, why are their fields? Well, we don't know.
You know, that's that's down to like why is there
anything we just this is as deep as we've gotten
(27:19):
so far, we don't know what the next layer of
knowledge or ignorance is, so we're struggling to understand what
it means. But you know, this is why we do it.
We look for the patterns, We try to identify the
weirdness in those patterns, and those lead to these questions
which eventually, we hope in fifty two hundred years will
lead to really deep insights about like why the universe
(27:40):
exists at all. It's like the classic chicken fields and
egg particles problem. You know, which came first? Which is
more fundamental and or tas obviously the egg came first.
I never understood that one egg led to the chicken.
What do you mean who laid the egg? The pre
chicken mom of the egg mutated chicken. It is a
(28:00):
pretty chicken, a chicken, Daniel. Well, if it annihilis with
an anti chicken, then and that's why this is not
a biology podcast, right. Well, it sounds like the answer
for Juan here is why not or stay tuned Like
he's asking pretty basic questions of like why are things things? Yeah,
we just don't know one and we're trying to figure
(28:22):
it out. And these are the deepest funnest questions to
think about, so don't give up, we'll figure it out.
All right. Well, I guess one won't be sleeping better
at night after that one. But we have one more question,
and this one's about alternate stars, which I thought was
pretty cool. But and so let's get into it. But
first let's take a quick break. All right. We're answering
(28:52):
questions from listeners today, and we've had two pretty good ones,
and this last one kind of blew my mind a
little bit. So some to hear has a question about
whether or not as stars can be different. I really
enjoyed a recent episode on turning Jupiter into a star
and how what would it be involved with that? I
(29:12):
was wondering, since you're talking primarily about fusion based stars,
what would happen if you had a fission based star?
Do they exist? Are they theoretically possible? What would they
look like? All right? A pretty interesting question. I guess
he's asking whether you can have a star that works
based on fission and not fusion, or is he asking
(29:35):
whether stars can be fizzy? What would it taste like
to sip a star? How long a straw would you
need to safely sip the star. It might be a
little hot, better blowing there, use some gravitational waves to
cool it off. Yeah, there you go, all right, But
I guess the question is could you have a fissi
and stand So maybe let's recap whether fission powered stars.
(29:55):
So the reason that the Sun is a star, the
reason it glows, the reason it is giving off energy
is that doing something that releases energy, and that's fusion,
and fusion is taking lighter elements like hydrogen or helium,
things that have just like a couple of protons and
sticking them together and when they stick together, a lot
of energy is released. So that's called fusion. Join things together,
(30:19):
and anything on the periodic table. It's like lighter than
iron because of the way the protons and neutrons are
stuck together in the vagaries of the strong force. When
you join them together, you release energy, so it gives
off energy. You can essentially combine this stuff, make bigger,
heavier elements and make your star glow. And that's what
powers all of the stars in the universe. And that's
(30:41):
always been a little bit confusing that the idea that
by joining things together it releases energy. Yeah, joining things
together releases energy. It takes energy to pull them apart.
Think about it like that. I see so like it's
kind of like when you bring to magnets clothes together,
they snap together and they make a sound. Yeah. Like
that sound is almost kind of like the energy released
in the center of a star. Yeah. And it's all
(31:03):
about the configuration of these protons and neutrons together. And
it's a bit counterintuitive because it's all the same particles, right,
There's just protons and neutrons, and either they're attracting or
they're repelling. And remember that all the protons, they're repelling
each other. The whole reason the nucleus holds together is
because of the strong force. The strong force sends these
gluons back and forth between the neutrons and the protons
(31:24):
and really ties the thing together. The fact that the
protons are positively charged and pushing away from each other
is really not even relevant anymore because the strong force
is so powerful. And it's also really hard to do calculations,
like it's not a simple thing to figure out what
some arrangement of protons and neutrons will feel like. But
we do know that for elements lighter than iron, when
(31:47):
you stick them together you get energy, and that's fusion, right,
So that that's most stars that we know. At least
our star works on fusion. It's fusing hydrogen and helium.
It's joining things to create that energy to power the
star and also to make the heavier elements. Right, fusion
needs light elements. You need stuff that's lighter than iron.
(32:08):
And in the Big Bang we got mostly hydrogen, tiny
little bit of helium and lithium, etcetera. But most of
the heavier stuff in the universe was made by fusion.
That's how you do it. Right. All of our atoms
all in in our bodies, we were all made at
the center of stars. That's right. All the uranium and
all the iron and all the heavy stuff in the
universe was made in these stars. That's how you do it.
(32:29):
So all the stars that are out there, they're fusing
and making this stuff, making particles. But where does the
particles come from, Daniel, They come from the banana universe.
They slipped in through a worm, all right. So that's
one way to make energy fusion fusing things together. But
you can also make energy by splitting atoms apart. That's
called fission. That's right. If you have stuff that's really heavy,
(32:51):
heavier than iron, then you get energy by doing the opposite,
by breaking stuff apart. Like uranium is really heavy, much
heavier than iron, has more protons in the nucleus, and
when it splits open, it releases energy. So it's the opposite.
Above iron, you get energy, when you split below iron,
you get energy when you fuse. Right, there's like energy
(33:13):
stored in that. It was somehow these elements came together
and they're storing energy. They have energy inside of them,
stored in their bonds, and then when you break them apart,
that energy flies off. Yeah, if you like mechanical analogies,
you can think of it like they're tied together and
the springs are compressed, and when you cut the string,
they fly apart and all that energy is then released.
So you're releasing all that energy. And so this is
(33:35):
another way to generate energy, and we do this in
nuclear power plants. You find heavy uranium in the crust
of the earth and you let it decay and you
gather that energy. That's fission, right, Yeah, that's what all
of our nuclear reactors use, is fission, that's right. We
have not been able to make fusion work on Earth
in a sustainable way with a few brief spits and
spats of it here and there. We don't have like
(33:56):
a fusion reactor yet. I mean, people are working on it.
It's an awesome brodjet And if we could would be
said in terms of energy, right, absolutely, because fusion doesn't
create dangerous byproducts. You know, it works with very light
elements and creates very light elements, and it's much more efficient.
The fuel source for it would basically be hydrogen, which
we can get a lot of in the ocean, So
(34:16):
fusion would be pretty awesome, right. You don't need uranium
or any of these radioactive elements. All right, So then
the question is, can you have a star that works
using fission? Like could you have a star where things
at its center are being broken apart instead of fuse together? Yeah,
And it's a great question, and it's exactly the kind
of question of physicists would ask, you know, like, well,
if you can do it this way, can you do
(34:37):
it the other way? You know, you have two ways
to make energy. Could you use either of them to
power a star? It's a really great question. But the
first part of his question was like do they exist? Like,
are there stars out there that are fission ng and
that's why they are burning? Right? So do they exist?
Are there stars that work from using fission? We do
(34:57):
not think so. We think that every single star out
there in the night sky is fusing. And the reason
it's pretty simple is that the universe is almost all hydrogen.
In the Big Bang, the universe was made, and it
was almost all hydrogen after a few hundred thousand years,
and a little bit of helium was made during the
Big Bang, but basically it's all hydrogen, and so that's
the only fuel that's out there. You've got a universe
(35:18):
filled with fuel for fusion and very very tiny amounts
of the fuel you would need for fission, right, And
the only way to make them is through those other stars,
not even like the dimmer stars like the red dwarfs
or something, even the brown dwarfs like those are fusing. Yeah,
those are fusing special kinds of fusion. Sometimes you have
deuterium in their or tritium or whatever. But it's all fusion.
(35:40):
And that's just because the fuel in the universe is
the fuel unique for fusion, not for fission. I mean,
if we had a different universe where the Big Bang
mostly made uranium and plutonium. Then yeah, you might have
like vision based objects out there, but those heavy elements
are very very rare. In fact, like we're sitting on
top of a pretty rare clumb of stuff. You know.
(36:01):
The Earth is mostly iron and nickel and really heavy
stuff that's pretty rare in the universe, like by mass. Yeah,
and that's what's kind of keeping the Earth hot at
its center. Yeah, part of it is gravitational pressure, but
another big part of it is the fact that we
have radioactive heavy stuff in the center of the Earth
that's decaying and it's emitting energy. And so in some
(36:22):
sense you can sort of think of the Earth is
like kind of a fission powered star because it's a
really dense blob of stuff that's being kept molten by
the energy from fission. Earth is pretty heavy metal. Yeah,
if you'd like to think about it, you can imagine
that we're sort of living in the atmosphere of a
fission powered star. Yeah. Cool, But the Earth is not
(36:46):
called a star. I guess it has kind of a
fission engine and its core inside, but you wouldn't call
it a star. You wouldn't call it a star because
it's not glowing where the Earth doesn't give off light,
and I think to be called a star even like
in the infrared, well the Earth does in the infrared,
like everything does. You're right, everything in the universe glows
at some temperature, but it doesn't glow in the visible.
(37:06):
It doesn't glow in the in the X ray. And
so I think to be a star you really need
to be like glowing and burning consuming the fuel. We
don't sparkle. We don't sparkle exactly. You can imagine trying
to do that, like you know, play sort of a
play god and say, are right, I'm gonna take a
huge amount of fission fuel like uranium, make it into
a gas and just like drop it somewhere in deep
(37:26):
space and think about like what would happen? Then, I
think that's what Mike is asking. Is it theoretically possible
to have a star that works from fission? So this
is this is what you are experimenting with here, Like
like how would you even make one? If it's possible
at all? If you could get enough uranium. We we're
talking about like an enormous amount of uranium, make it
into a gas and drop it in space. Well, gravity
(37:48):
would do its thing, just like it did for the
formation of the Sun. It would gather all that stuff
together and pull all those uranium nuclei, all those atoms together,
eventually get them close enough so that when they decay,
they knock into each other and create chain reactions and
you would get real fission. You would get you know,
in effect, burning and empowering this thing through fission, because
(38:08):
I guess that's how nuclear bombs work, right, Like, if
you put enough unstable uranium together at some point, it's
gonna cause a chain reaction which will explode. Yeah, And
that's how the sun works, just with fusion. That it's
the energy from fusion is providing the energy needed to
create fusion. That's called ignition, right, And so if the
(38:30):
release of energy then enables the next release of energy,
then you have someone which is self sustaining. And oh really,
you know our son. I thought, like what causes things
to fuse was the gravitational pressure. But it's also you mean,
like the energy pressure from the other explosions. It's a balance, right.
The reason the Sun is not exploding is because of gravity,
and the reason it's not collapsing is because of the
(38:51):
energy pressure, and so in our theoretical uranium star something
similar would happen. Eventually, like gravity would pull this stuff together,
which would increase use the rate of which stuff is
decaying because you know, the decay products are not bouncing
into each other more often. But eventually the energy being
released from fission would balance out the gravity. You get
some like interesting you know, balance there. And I don't
(39:13):
think it would be as dense as our sun. Vision
is not as powerful as fusion, but just release as
much energy. I'm not sure exactly what it would look like,
but theoretically that kind of thing is possible. You just
have to get enough uranium and compress it. Yeah, the
recipe is get a galaxy is worth uranium galaxies isolated
(39:34):
in space and then wait a few million years and
the gravity will bring it together and then they'll will ignite.
And I'm not sure exactly what it would look like like,
how dense it would get, and whether it would be
hot enough to get the surface to be like a
glowing plasma, or whether like other things would take over
before you even got there. But I think theoretically, you know,
it might be possible. Wudn't it be unstable like a
(39:56):
nuclear ball like wouldn't in the chain reaction would run
away and which is explode, right, but you have that
pressure would keep blowing it out, which would lower the density.
The same thing happens in the sun. Right. It's sort
of like self regulates because the hotter it gets, the
more it's pushing out, the less dens it gets, and
that lowers the rate of the reaction. All right, So
it sounds like the answer for Mike is that, yes,
(40:18):
fission stars are possible, but not likely to exist because
they are pretty difficult to make work. That's right, because
the fuel just isn't out there, we think, and we're
also not exactly sure what they would look like, and
take a pretty sophisticated simulation to get like a realistic
answer for what that star would look like. But theoretically
(40:39):
the process is very similar to fusions. You just need
the right fuel and the right conditions. And in the
meantime we are sort of kind of sitting in a
fish and star, right, which is the Earth, that's right.
Fishing is warming your feet, all right? Cool? I think
Mike can sleep will at night? Are you been having
trouble sleeping? Jorge? I feel like all these questions are
now related to like a well being. I'm just fetting
(41:02):
a lot of empathy for these curious people. Well, curiosity
does keep me up at night, but what lets me
go to sleep is knowing that we just need to
think about it and work on it, and eventually we
will get these answers. The history of science is filled
with people wondering about basic stuff that a hundred or
two hundred years later even school children know the answer to.
So eventually our deepest fundamental questions will be you know,
(41:24):
like in story books in the year three thousand and
we talked to preschools. All right, Well, thank you to
Henry Kwan and Michael for sending in their questions, and
thanks to everyone who sent their questions. And it's always
kind of amazing and cool to think about all those
people out there thinking about the universe and coming up
with their questions and even more exciting stumping Daniel. So
(41:46):
thank you everybody for trusting us with your questions, for
taking the time to write in, giving us feedback on
the show, and letting us know what you'd like to
know more about. We want to hear from you, so
please write to us at Questions at Daniel and Jorge
dot com. And thanks to everyone also who has been
leaving us ratings and comments and telling all their friends
about this podcast. We really appreciate it well. Thanks for
(42:08):
joining us, See you next time. Thanks for listening, and
remember that Daniel and Jorge Explain the Universe is a
production of I Heart Radio. For more podcast for my
heart Radio, visit the i heart Radio app, Apple Podcasts,
(42:29):
or wherever you listen to your favorite shows.
Hey, Daniel, how's our email inbox looking these days? Oh? Man,
like usual, it is jammed full. We have a big
pile of questions. Really, people still have questions. You thought
maybe we'd like answered all the questions in the interview. Well,
we have done about two episodes and ten listener question episode.
I figured, you know, eventually people might be satisfied and
know all the answers to the universe. I think that
(00:30):
the more we answer people's questions, the more questions they have.
Man sciences like that, isn't it always teasing you with
an answer and then dropping more questions? And thank goodness,
otherwise we would run out of episodes and then we
wouldn't be here. Hi am more handmaker, tunist and the
(01:00):
creator of PhD comics. Hi. I'm Daniel. I'm a particle
physicist and I'm a professional email question answer. Wow. Really
you get paid for that? I just feel like a
professional what I'm doing it. I feel like that's what
I have to do to get paid, which I don't
do very well, but which probably explains a lot. But
sometimes people write into the podcast and I think this
might be the only time this person has asked the
(01:22):
question to a physicist and gone an answer. So I
feel a little bit like I'm representing physics in some way. Wow,
you're the ambassador of the physics nation a little bit. Yeah,
So I feel some responsibility to know, be polite and
funny and insightful and all that stuff. You know. It's
like that first day of class in college. Sometimes I
get to teach freshman and I am on the first Monday,
(01:43):
and I feel like, Wow, I am college for them.
So there's a bit of pressure there. Yeah, and if
someone walks out, you're like, well, I guess I failed physics.
Nobody walks out on my emails fortunately, But anyways, welcome
to our podcast. Daniel and Jorge explained the Universe but
suction of I Heart Radio, in which we tackle all
the questions in the universe, all the things that science
(02:05):
wants to know and all the things that everybody wants
to know. How did the universe begin, what is it
made out of? How is it going to end? Why
are we all here? And should you eat your bananas
when they're black or green? That's right, it's a very
important physics question. What can kill me out there? Daniel?
And how? And when? Basically everything can kill you out
there if you're creative about it. Love, Love can't kill you, Daniel.
(02:27):
Have you seen Titanic? Soh, alright, love can kill Leonardo
to keep you but exactly anyways, Yeah, it's our podcast
where we talk about the universe and all the amazing
things in it, and we also talk about the questions
that not only scientists and physicists have at the cutting
edge of knowledge and research, but also the questions that
everyday people have about how things work and why things
(02:49):
are the way they are. That's right, because questions belong
to everybody, and asking questions is part of being human.
It's impossible to be a conscious being in this world
and I'll look around you and wonder why things are
the way they are, why they aren't different, and what
it means about the way the universe works. And scientists
are just like that. They're just people who have answered
more of their questions so far, and they're onto the
(03:10):
most interesting cutting edge questions. And so our goal today
is to bring you up to speed, to introduce you
to the forefront of knowledge and tell you all about
the questions that scientists are asking. And it turns out
the scientists are asking a lot of the same questions
that you are. It's right. Are you trying to tell
me not to look to scientists for answers, Daniel, I
just look to them for more questions. I'm trying to
(03:31):
tell you that we're all scientists, were all asking these
deep questions about the universe, and we'd all like to
know the answer. Great. So to be on the program,
we'll be doing another one of our famous listener question
episodes where we answer questions from listeners. So to be
on the podcast, we'll be tackling listener questions number eleven eleven. No,
(03:54):
we've answered a lot of these and we have a
big pile left, So if you've submitted your question and
haven't gotten answer yet, stay tuned. We're getting to them.
We love these listener Questions episodes, and I always love
these episodes because people sending the most interesting questions. These
are the really fun ones. People writing questions all the
time the email, and sometimes I'll fire off a quick answer,
but if it's a really good, juicy question that I
(04:15):
think a lot of people would like to hear the
answer to, or Brinkley, I need a little bit of
time to research, and then we'll do it on the
podcast cool. So today we have three pretty cool questions
from listeners from all over the world, and they have
to do with gravitational waves about the nature of matter
and whether or not you can have a different kind
(04:36):
of star than the ones that we are used to.
So let's jump right into it, Daniel, and let's start.
But this first question from Henrik Sumberg from Sweden, who
asks can a gravitational wave kill you? Or what will
you feel when you're close to a wave like the
one that was found by Ligo. Wow? What an awesome
(04:56):
question and a little terrifying. You know, do we thought
about gravitation with dying from gravitational waves which I just
assume we're rolling through us, but apparently they can kill us?
Can they kill us? Because that's a question? Well, it
is a great question. You know. These things are ripples
in space itself, and it's cool that we build observatories
that can spot them. But the ones that we've seen
(05:18):
so far are really far away, so it's a totally
valid question to ask what would happen if you got
close to it? I guess it's kind of like asking, like,
can of an ocean wave kill you? Right? I suppose?
I mean ocean waves certainly can kill you. I think
it's more like asking, you know, can the sun kill you?
And the answer is basically the same as from a
great distance, the sun will just make it nice and toasty,
(05:38):
but if you get too close to almost anything, it'll shrick. Well,
let's maybe recap for people who don't know. So gravitational
wave is like a wave with like a ripple in
spacetime itself. That's right. And the idea is that gravitational
information doesn't move instantly, like if the Sun disappeared, we
would still feel it's gravity for the eight minutes it
(06:00):
look for that information to get to us, because gravitational
fields ripple, right, you delete something from the universe, then
the information propagates out the field itself ripples. Right, It's
not instantaneous because nothing instantaneous in the universe exactly, nothing
is instantaneous. No information can move faster than the speed
of light. And so gravitational waves are when you have
(06:22):
really strong, very powerful objects that are accelerating around each other,
so they're making waves in space itself. Remember, gravity is
just the bending of space. You put the Sun in
the center of the Solar system, it bends the space
around it, so that the Earth's most natural path is
one to move in a circle around the Sun. And
so when you move masses around, when you accelerate them
(06:44):
back and forth around each other, it makes these waves
in space. And that's what gravitational waves are there, like
the contracting or the pulling on space itself. It's it's
really kind of bonkers, like the changes in the gravitational field.
Kind of Yeah, you can think about it two different ways.
If you like to think of space is flat and
having gravitational fields in it, then you can think of
(07:05):
it as the rippling of those gravitational fields in space.
But if you like to think about it like Einstein did,
then you know there is no gravity. There's just sort
of changes in the shape of space. And from that perspective,
gravitational waves are ripples in the shape of space, like
things get closer and then further apart, and closer and
further apart. That's what happens when a gravitational wave passes
(07:26):
you by, And I guess that we're like a wash
in gravitational waves. Like if I move my arm around
in a circle, I'm creating gravitational waves. But they're just
so small that nobody can notice. That's right. Just like
there's gravity between you and your arm, and you and
that box in front of you, and you and that banana,
you just can't feel it because gravity is just so weak.
(07:47):
Anytime an object with mass moves and accelerates, it generates
a gravitational wave, but because gravity is so weak, you
usually just can't sense it. We can only sense gravitational
waves from really really big thing things, really massive things,
precisely because gravity is so weak. It's almost kind of
like we're all swimming in like a thick Google or
(08:07):
something like if space was a Google and we're all
swimming in it. You know, any motion that I make,
or any motion that any planet makes will sort of
generate a little ripple in that Google. Yeah, precisely, And
we are listening for those ripples, and we've been listening
for them for a few decades and recently, just a
few years ago, they actually detected these ripples. As an
incredible story because people had thought these ripples existed for
(08:29):
a long long time, but they thought it might be
impossible to detect them because they are so small, because
they're so faint, because gravity is so weirdly weak. And
they had to build a really powerful device it's called
a laser interferometer with two long arms on it that
measures the length of these like kilometer long arms to
(08:50):
see if they shrink a tiny bit like the width
of a proton. So it's a really really difficult measurement
to make because these gravitational waves are very very subtle, right,
because you know, like if I shake my fist, I'm
generating ways. But there's probably no way that anything that
we have could possibly measure that. Right. Probably you need
like these giant machines just to measure that the big
ones coming from space, that's right. But you know, I
(09:12):
thought for a long time even the big ones coming
from space would be impossible. What I was a grad
student thinking about what field of physics to work, and
I considered going to cal Tech and working on the
gravitational wave system. But I remember thinking, of these guys
are never going to spot out, and they're gonna be
working forever and never see it. And hey, I was wrong,
and I'm glad they've been proven wrong. They found something
(09:33):
amazing about the universe and won themselves a Nobel Prize along.
So what you think is impossible today might be totally
routine in twenty years. You never missed that on that rate?
Did it? Didn't get to surf all the way to Sweden.
You didn't catch the wave. Yea. And we could have
met at cal Tech? Isn't that weird? Yeah, that's imagine
an alternate reality where you did go working Lego and
then we somehow met there. Yeah, but then we would
(09:55):
have met in person, and we probably wouldn't have gotten along,
probably wouldn't have started working to go there anyway. So
there are gravitational waves all around you, but only really
massive objects create gravitational waves that we can detect, right,
And that's what we measure with Lego. We measure waves
that are coming from space from really crazy events. And
so I guess Henrick's question is can one of these
(10:16):
waves kill you? Like, if you're standing there and a
big wave comes through you, is it gonna affect you
or could you even feel it? Because you know, if
it's bending and stretching space, would in all my particles
still still stay together? Yeah, in principle, these things do
have an effect on you also, right, you do get
bent and stretched when gravitational waves go through you, the
ones that hit Earth they affect things that are a
(10:38):
kilometer long by about the size of a proton, so
the effect on you is totally negligible. You can't feel them.
But these are black holes that are like one point
three billion light years away, And one of the reasons
why they're so faint is because the black holes are
so far away. So it's reasonable to ask, like, if
it was closer, if there was black holes colliding nearby,
(11:00):
making big gravitational waves closer, what would be the effect
on your body? And it's certainly true that it would
pull and push you as well. Wow, yeah, because I
guess like if you're really far away from an explosion
or something, then you don't feel the effects very much
because like you might feel a little bit of the
wind or the air kind of hitting on you, but
(11:20):
you wouldn't necessarily be hurt. But like, what if you're
right next to the explosion, that would be bad news.
Absolutely it would be bad news. And the closer you
get to these things, the more powerful they are. The
thing is, though, gravitational waves never really that powerful. Like
take one of these events, these black holes that at
one point three billion light years away, the wave is
really really weak over here. It's one part in ten
(11:43):
to the twenty one. So that means that if something
is like ten to the twenty one long, then it
shrinks by one. Now ten is predunculously big, right, which
is why these things are so hard to see. So
bring yourself closer, right, say you get, for example, just
one light year away from these black holes, and just
to paint a picture, lego measures like spinning black holes,
(12:04):
like black holes that are collapsing into each other, and
so they're it's like the death sworld of two black holes. Yeah,
because to make gravitational waves, you can't just have static mass.
That doesn't make a wave. You need stuff that's accelerating.
And so these black holes that are swirling around each other,
attracting each other, spinning in to their eventual collision, there
are great opportunities to see gravitational waves because there's huge
(12:25):
amounts of mass and there's a lot of acceleration because
they're spinning around each other. So now we're talking about
being one point three light years from two black holes gliding,
and you're saying this is where it starts to get dangerous. Well,
it doesn't actually get dangerous from the gravitational wave point
of view because the power of that is like still
one part intended the twelve, you know, so like if
you brought the whole earth within a light year of
(12:48):
these black holes, then the whole earth would shrink by
like a hundreds of a millimeter, and one part in
tend of the twelve is very small whole earth. So
would that affect me? Like, it doesn't sound like it would,
but I don't know, like maybe we'll scramble all of
my atoms or something. No. One, one hundreds of a
millimeter full of the whole earth is unmeasurably small just
for you, right, so you wouldn't even notice it. It
(13:10):
would be very difficult for you to notice. It could
break up molecules or something at that level. Molecules, you know,
because you're if you're stretching molecules. Molecules are pretty small.
Molecules are pretty small, but they're pretty tough. You know.
They're basically held together by these little bonds which are
like springs. And so it's like if somebody came and
tugged on you with a force, you know, enough to
pull you by one dred of a millimeter, you would
(13:33):
pretty much survive that, right, it's like it's a very
gentle tug on the entire earth, right, so even just
on you, it would be almost imperceptible. All right, So
it's still pretty save with a light ear. What if
I get closer, Yes, if you get within like you know,
ten thousand kilometers of the center of this black hole,
then we're talking about gravitational waves that are now serious.
(13:54):
They're like one part in the thousand. Like I would
shrink and contract by you know, a couple of millimeter,
couple of millimeters. Yeah, and so again I think you
would survive that. Like, really, you shrink and contract more
than that every day just walking around. Your height changes
more than a millimeter because of the compression on your
spine from walking around. I don't know. Maybe you never
get up from your chair so you don't drink as
(14:15):
much as other people. But somethings I laid down in
my chair and there's some stretching going on. Well that's
good for your back and for your height. But you know,
your height changes by a lot more than that just
during the day. So I don't think I would have
any effect on your health. But I see we're pretty
squishy again, We're pretty squishy. But you know, say, for example,
you're in a space suit, having your space suit get
pulled by one part in a thousand, you know that
(14:35):
could like crack the glass or break something important, or
if you're in a space ship, you know, maybe the
electronics are sensitive. So I wouldn't recommend. What about my bones?
Could my bones take it? Yeah? Your bones could take it,
for sure. I mean one part in a thousand is
not very much your bones, even though they feel pretty tough,
there's some spring to them. You're talking really close in
thousand kilometers from the center of a black hole is
(14:58):
like you're like right there, it's very us and you're
not even going to survive getting that close, Like you're
going to be torn apart by the gravitational forces that
exist just from the black holes, well before the gravitational
waves do anything to you. Really, Yeah, because remember near
a black hole, the gravitational forces, just the static ones,
(15:18):
not the changing ones, not the ripples in the gravitational field,
just the field itself is really really strong. And the
closer you are to the black hole, the stronger the forces.
So if your toes are closer than your head, then
there's a stronger force on your toes, and there is
on your head, which is the same thing as the
black hole pulling you apart. So if those forces that's
called tidal forces, the force on your head and your
(15:40):
toes is very different, then you get yanked apart. And
you don't have to be very close to a black
hole before those forces start to be larger than your
body can take. So most likely the waves won't kill you.
It will be something else. That's right. The shredded pieces
of your body that survived that close to the black
hole will not be damaged very much by the gravitational wave.
(16:01):
You'll already be torn apart alright. So then I guess
answer for Henrik is no, like a gravitation a wave
can't really kill you because if if there's anything causing
a gravitational wave that big, then it's probably gonna kill
you in some other way. That's right, exactly. So if
gravitational waves get big enough to do any damage, you're
(16:22):
probably already dead. All right. Well, I feel a lot better.
I was getting kind of concerned there. I was like,
it's something else I have to worry about. No, just
avoid black holes is good general advice. Stay at least
ten thousand kilometers from them. If not more, somebody should
put up signs or something caution universe singularity ahead. All right, well, Henry,
(16:45):
I hope that answered your question, and I hope you
can sleep a little better at night knowing that gravitational
waves can't really kill you. Maybe those gravitational waves will
be get rocking him to sleep, sleep to the sound
of the universe. All right, Well, let's get into some
of these other questions about the nature of matter and
alternate stars. But first let's take a quick break. All right,
(17:16):
we're back answering questions from listeners. Which are the best questions?
And I have to say, Daniel, these questions we got
today are pretty intense. I feel like usually people ask
sort of like funny situations or you know, more basic things,
but these are like intense, like can a gravitational wave
kill you? And making me question the nature of matter? Well,
(17:37):
we are living in strange times and everybody's at home
thinking deep thoughts. I guess. All right, Well, the next
question we have for today comes from one Ignacio Vadagas,
and he didn't say where he's from, so we're just
going to assume Jupiter. Maybe he emailed as um, you know,
fourteen years ago and he only just got the email.
All right, Well, here's what one wanted to know. I
(17:57):
was just wondering whether we have any idea yes, as
to why there is mutter, what causes energy to be
sequestered in what we call particles? Well that is deep
stuff that is deep, Like why are we here? He's
basically asking. Yeah, there's a lot of possible angles to
this question. I really wish I could chat with one
and figure out, like what is he asking? Is he
(18:18):
asking like why do we have matter or not just radiation?
Or why is there matter or not antimatter? Or why
is there something rather than nothing? Or why is energy
sort of clumped together into particles? Or there's a lot
of really fun angles. You want to ask him questions
about his question. I want to make sure we're answering
the like deep deep curiosity that's wormed its way into
(18:40):
his brain. I want to make sure that we are
We're going to touch on the question he really wants answered. Well,
it's it sounds like a pretty interesting question. I guess
he's asking, we have the universe and when we know
about energy, but why do we have matter? Like why
does matter exist in the universe, Like why the energy
suddenly decide to, you know, form into little particles of matter. Yeah,
(19:02):
that is a great question, and you know, the short
answer is, we really just don't know. But how much
we don't know sort of depends on what you think
is the most basic element of the universe, you no,
Like we have talked on this podcast before that sort
of historically we discovered that things are made out of particles.
(19:25):
You know, that all the stuff around you can be
broken up into smaller pieces, and those pieces can be
broken up into smaller pieces, and those can be broken
up in the even smaller pieces, and it gives you
the sense sort of that like particles are the basic
unit of the universe, that everything is made out of particles, right,
And the way particles interact is through these things called fields.
So that's sort of historically the way our understanding the
(19:48):
universe was developed. But more recently we have sort of
a new view on what the basic element of the
universe is, and that suggests that particles are not really
the building block of the universe of matter itself, but
that the deepest thing are actually the field. Wait, aren't
they the same thing? Like isn't a particle like what
they call an excitation of that field or like a
(20:09):
blip in the field. Yeah, Well, this new view says
exactly that that particles are just a weird state of
a field. But that says that the fields are the
deepest thing. You know. The particles aren't the fundamental building blocks.
They're just like a configuration of the fields. It's like,
you know, what's more fundamental, your hand or a fist.
Your fist is just your arrangement of your fingers in
(20:29):
a certain way, or like what's more fundamental a wave
or the ocean? Yeah, precisely. And so the fields are
the ocean, and the particles are the waves in that ocean.
And so more modern view is that everything in the
universe is filled with fields. We have an electromagnetic field,
and the waves in that field are photons. We even
have an electron field. It's different from the electromagnetic field.
(20:52):
Waves in the electron field are electrons. And then every
particle that we're familiar with has a field, and those
particles are just wiggles in those fields, like little ripples,
like a little echo or a little blip, yeah, like
a little packet. And then it's a really interesting and
fun question to ask, like, well, why do those fields
have packets? Right? One of those fields just sort of
(21:13):
slash around and have energy everywhere. I think this is
sort of what he was asking, like why is energy
clustered together into these little blip called part of where
did those blips come from? Yeah? And why do we
have blips and not just you know, blushes or squishes
or squashes or whatever, because then we wouldn't be here
to answer it's a question. Yeah, And so you know,
(21:33):
the first the deepest answers, we really just don't know.
But we have sort of two suggestions maybe sort of
directions of thought or people sort of you know, groping
in the dark towards ideas. And one is that these
fields are not just fields, their quantum fields. These fields
can't just have any particular value. They seem to have
(21:54):
certain discrete set of states that they can take, you know,
then go up one unit of energy or two two
units of energy, but not one point three seven nine. Oh,
I see, they like um. They're kind of fuzzy. You
can move this field in like half of up wave. Yeah, exactly.
And we associate these quantum units with particles. Like when
the field gets one more unit of energy that that
(22:16):
field can absorb, we consider that one more particle. And
in quantum mechanics we actually do the math. We call
these things counting operators. We like create new particles, destroyed particles.
That's how you put energy into the field. So one
way to think about it is that that a particle
is just like a quantized unit of energy in the field.
I guess maybe is it kind of like if you
(22:36):
throw a whole bunch of water into the air, Like
water tends to, you know, kind of clump into droplets,
you know, it doesn't just kind of spread out when
you throw it up into the air. Yeah, it certainly does.
I'm not sure if that's because it's quantized or there's
surface tension, or surface tension leads a quantization. That's actually
really cool thought there probably is a connection there. But
that's kind of the idea is that it tends to cluster,
(22:58):
or it tends to like little bit tends to clump
into little bits. And the second idea, which is connected
is that we've noticed that there are some symmetries to
these fields, Like these fields don't just do anything, you know,
they have rules that they follow, like the field follows
the same rules over here as they do in another
part of the universe. Or if you spin yourself in
(23:19):
the field, it follows the same rules as if you
hadn't spun yourself. So they're these symmetries, translational and rotational
symmetries to the fields themselves, right, And this is going
to sound like a really weak and fuzzy argument, but
essentially a particle is the simplest thing that can exist
in those fields that satisfies those symmetries. Like that's how
(23:41):
you explain why it forms into particles. Well, there's this
feeling and quantum mechanics that sort of everything that can
happen does happen. So if it's not explicitly forbidden by
some rule, then you will see it happen eventually. And
so particles are sort of like the simplest thing that
can exist that isn't ruled out by some basic symmetry
(24:03):
or conservation rule or whatever. So therefore they do exist.
Now that's a pretty weak argument because there's lots of
times that we expected something to exist, like a new
particle or whatever, we don't see it exists, and so
we say, well, therefore there must be some new rule
that eliminates it, and we just add that rule to
the list. So, you know, it's not like a lot
(24:23):
of these rules have deep understanding them. Some of them do.
Some of them come out of like really beautiful symmetries
of nature, etcetera. But some of them seem a little
ad hoc. So it's a totally valid open question sort
of at the edge of physics and philosophy, like why
do these particles exist? Why do we have any particles
at all? Why do the conservation laws allow for these particles?
(24:44):
Why not something else bigger and squishier. Maybe a way
to interpret his question is like, could you have a
universe without particles? Could the universe just kind of could
there be a version of this universe where no particles
ever formed and everything is just kind of like the
fields are just totally on blipped where this fields are
sitting there. You know, there are some other configurations of fields,
but you know, those universes would not lead to people
(25:06):
asking questions about those particles and those podcasts. So it's
possible those universes could exist, but they wouldn't be as
interesting or as rich, and so they wouldn't be in
them asking this question. So this sort of this selection
effect that we only tend to ask these questions in
universes where there are interesting things happening. But we already
we have ideas for like other ways you could arrange
(25:28):
quantum fields that are not particles, these things called like squirmons,
that are not the same kind of clusters of energy
in the quantum fields, but in fact are these like
we're not these other stable configurations of quantum fields that
are not quite particles. They don't act the same way. Interesting.
I guess maybe the answer you tell me is that
you know, in quantum physics it's all kind of like statistical,
(25:52):
and so if a field can kind of form into
a particle, it probably will. It probably will. Yeah, particles
will just spontaneously occur, and probably especially if you have
like energy, right, if you like, if there's energy around,
those particles are going to pop up. And that's where
we come from. And I would say that like probably
half of the theorists out there, the people who think
really deeply about quantum theory thinking that way. They think
(26:14):
the fields are the basic thing, and the particles are
like manifestations of those fields. But you know, the other
half of the community thinks about it the other way.
They think, no, no, no, the basic thing in the
universe are particles and fields. Those are just you know,
virtual particles. So this is just how particles talk to
each other. They think of the fields as you know,
(26:36):
just like a huge swarm of very briefly living particles,
because the particles are the things we interact with, right,
The fields are a little bit more abstract. The particles
are the things that we like, we can see, we
can detect, we're made of them. So there's a bunch
of people out there that think that particles are the
basic element of the universe and not the fields. Like
if you didn't have particles, you wouldn't have fields. Yeah, yeah, precisely.
(26:59):
And and if you ask those people like well why
are their particles, well, you know, they have no idea
because they just start from the particles, just because that's
the aw just because it's like asking the other half like, well,
why are their fields? You're telling me particles are made
of fields, great, why are their fields? Well, we don't know.
You know, that's that's down to like why is there
anything we just this is as deep as we've gotten
(27:19):
so far, we don't know what the next layer of
knowledge or ignorance is, so we're struggling to understand what
it means. But you know, this is why we do it.
We look for the patterns, We try to identify the
weirdness in those patterns, and those lead to these questions
which eventually, we hope in fifty two hundred years will
lead to really deep insights about like why the universe
(27:40):
exists at all. It's like the classic chicken fields and
egg particles problem. You know, which came first? Which is
more fundamental and or tas obviously the egg came first.
I never understood that one egg led to the chicken.
What do you mean who laid the egg? The pre
chicken mom of the egg mutated chicken. It is a
(28:00):
pretty chicken, a chicken, Daniel. Well, if it annihilis with
an anti chicken, then and that's why this is not
a biology podcast, right. Well, it sounds like the answer
for Juan here is why not or stay tuned Like
he's asking pretty basic questions of like why are things things? Yeah,
we just don't know one and we're trying to figure
(28:22):
it out. And these are the deepest funnest questions to
think about, so don't give up, we'll figure it out.
All right. Well, I guess one won't be sleeping better
at night after that one. But we have one more question,
and this one's about alternate stars, which I thought was
pretty cool. But and so let's get into it. But
first let's take a quick break. All right. We're answering
(28:52):
questions from listeners today, and we've had two pretty good ones,
and this last one kind of blew my mind a
little bit. So some to hear has a question about
whether or not as stars can be different. I really
enjoyed a recent episode on turning Jupiter into a star
and how what would it be involved with that? I
(29:12):
was wondering, since you're talking primarily about fusion based stars,
what would happen if you had a fission based star?
Do they exist? Are they theoretically possible? What would they
look like? All right? A pretty interesting question. I guess
he's asking whether you can have a star that works
based on fission and not fusion, or is he asking
(29:35):
whether stars can be fizzy? What would it taste like
to sip a star? How long a straw would you
need to safely sip the star. It might be a
little hot, better blowing there, use some gravitational waves to
cool it off. Yeah, there you go, all right, But
I guess the question is could you have a fissi
and stand So maybe let's recap whether fission powered stars.
(29:55):
So the reason that the Sun is a star, the
reason it glows, the reason it is giving off energy
is that doing something that releases energy, and that's fusion,
and fusion is taking lighter elements like hydrogen or helium,
things that have just like a couple of protons and
sticking them together and when they stick together, a lot
of energy is released. So that's called fusion. Join things together,
(30:19):
and anything on the periodic table. It's like lighter than
iron because of the way the protons and neutrons are
stuck together in the vagaries of the strong force. When
you join them together, you release energy, so it gives
off energy. You can essentially combine this stuff, make bigger,
heavier elements and make your star glow. And that's what
powers all of the stars in the universe. And that's
(30:41):
always been a little bit confusing that the idea that
by joining things together it releases energy. Yeah, joining things
together releases energy. It takes energy to pull them apart.
Think about it like that. I see so like it's
kind of like when you bring to magnets clothes together,
they snap together and they make a sound. Yeah. Like
that sound is almost kind of like the energy released
in the center of a star. Yeah. And it's all
(31:03):
about the configuration of these protons and neutrons together. And
it's a bit counterintuitive because it's all the same particles, right,
There's just protons and neutrons, and either they're attracting or
they're repelling. And remember that all the protons, they're repelling
each other. The whole reason the nucleus holds together is
because of the strong force. The strong force sends these
gluons back and forth between the neutrons and the protons
(31:24):
and really ties the thing together. The fact that the
protons are positively charged and pushing away from each other
is really not even relevant anymore because the strong force
is so powerful. And it's also really hard to do calculations,
like it's not a simple thing to figure out what
some arrangement of protons and neutrons will feel like. But
we do know that for elements lighter than iron, when
(31:47):
you stick them together you get energy, and that's fusion, right,
So that that's most stars that we know. At least
our star works on fusion. It's fusing hydrogen and helium.
It's joining things to create that energy to power the
star and also to make the heavier elements. Right, fusion
needs light elements. You need stuff that's lighter than iron.
(32:08):
And in the Big Bang we got mostly hydrogen, tiny
little bit of helium and lithium, etcetera. But most of
the heavier stuff in the universe was made by fusion.
That's how you do it. Right. All of our atoms
all in in our bodies, we were all made at
the center of stars. That's right. All the uranium and
all the iron and all the heavy stuff in the
universe was made in these stars. That's how you do it.
(32:29):
So all the stars that are out there, they're fusing
and making this stuff, making particles. But where does the
particles come from, Daniel, They come from the banana universe.
They slipped in through a worm, all right. So that's
one way to make energy fusion fusing things together. But
you can also make energy by splitting atoms apart. That's
called fission. That's right. If you have stuff that's really heavy,
(32:51):
heavier than iron, then you get energy by doing the opposite,
by breaking stuff apart. Like uranium is really heavy, much
heavier than iron, has more protons in the nucleus, and
when it splits open, it releases energy. So it's the opposite.
Above iron, you get energy, when you split below iron,
you get energy when you fuse. Right, there's like energy
(33:13):
stored in that. It was somehow these elements came together
and they're storing energy. They have energy inside of them,
stored in their bonds, and then when you break them apart,
that energy flies off. Yeah, if you like mechanical analogies,
you can think of it like they're tied together and
the springs are compressed, and when you cut the string,
they fly apart and all that energy is then released.
So you're releasing all that energy. And so this is
(33:35):
another way to generate energy, and we do this in
nuclear power plants. You find heavy uranium in the crust
of the earth and you let it decay and you
gather that energy. That's fission, right, Yeah, that's what all
of our nuclear reactors use, is fission, that's right. We
have not been able to make fusion work on Earth
in a sustainable way with a few brief spits and
spats of it here and there. We don't have like
(33:56):
a fusion reactor yet. I mean, people are working on it.
It's an awesome brodjet And if we could would be
said in terms of energy, right, absolutely, because fusion doesn't
create dangerous byproducts. You know, it works with very light
elements and creates very light elements, and it's much more efficient.
The fuel source for it would basically be hydrogen, which
we can get a lot of in the ocean, So
(34:16):
fusion would be pretty awesome, right. You don't need uranium
or any of these radioactive elements. All right, So then
the question is, can you have a star that works
using fission? Like could you have a star where things
at its center are being broken apart instead of fuse together? Yeah,
And it's a great question, and it's exactly the kind
of question of physicists would ask, you know, like, well,
if you can do it this way, can you do
(34:37):
it the other way? You know, you have two ways
to make energy. Could you use either of them to
power a star? It's a really great question. But the
first part of his question was like do they exist? Like,
are there stars out there that are fission ng and
that's why they are burning? Right? So do they exist?
Are there stars that work from using fission? We do
(34:57):
not think so. We think that every single star out
there in the night sky is fusing. And the reason
it's pretty simple is that the universe is almost all hydrogen.
In the Big Bang, the universe was made, and it
was almost all hydrogen after a few hundred thousand years,
and a little bit of helium was made during the
Big Bang, but basically it's all hydrogen, and so that's
the only fuel that's out there. You've got a universe
(35:18):
filled with fuel for fusion and very very tiny amounts
of the fuel you would need for fission, right, And
the only way to make them is through those other stars,
not even like the dimmer stars like the red dwarfs
or something, even the brown dwarfs like those are fusing. Yeah,
those are fusing special kinds of fusion. Sometimes you have
deuterium in their or tritium or whatever. But it's all fusion.
(35:40):
And that's just because the fuel in the universe is
the fuel unique for fusion, not for fission. I mean,
if we had a different universe where the Big Bang
mostly made uranium and plutonium. Then yeah, you might have
like vision based objects out there, but those heavy elements
are very very rare. In fact, like we're sitting on
top of a pretty rare clumb of stuff. You know.
(36:01):
The Earth is mostly iron and nickel and really heavy
stuff that's pretty rare in the universe, like by mass. Yeah,
and that's what's kind of keeping the Earth hot at
its center. Yeah, part of it is gravitational pressure, but
another big part of it is the fact that we
have radioactive heavy stuff in the center of the Earth
that's decaying and it's emitting energy. And so in some
(36:22):
sense you can sort of think of the Earth is
like kind of a fission powered star because it's a
really dense blob of stuff that's being kept molten by
the energy from fission. Earth is pretty heavy metal. Yeah,
if you'd like to think about it, you can imagine
that we're sort of living in the atmosphere of a
fission powered star. Yeah. Cool, But the Earth is not
(36:46):
called a star. I guess it has kind of a
fission engine and its core inside, but you wouldn't call
it a star. You wouldn't call it a star because
it's not glowing where the Earth doesn't give off light,
and I think to be called a star even like
in the infrared, well the Earth does in the infrared,
like everything does. You're right, everything in the universe glows
at some temperature, but it doesn't glow in the visible.
(37:06):
It doesn't glow in the in the X ray. And
so I think to be a star you really need
to be like glowing and burning consuming the fuel. We
don't sparkle. We don't sparkle exactly. You can imagine trying
to do that, like you know, play sort of a
play god and say, are right, I'm gonna take a
huge amount of fission fuel like uranium, make it into
a gas and just like drop it somewhere in deep
(37:26):
space and think about like what would happen? Then, I
think that's what Mike is asking. Is it theoretically possible
to have a star that works from fission? So this
is this is what you are experimenting with here, Like
like how would you even make one? If it's possible
at all? If you could get enough uranium. We we're
talking about like an enormous amount of uranium, make it
into a gas and drop it in space. Well, gravity
(37:48):
would do its thing, just like it did for the
formation of the Sun. It would gather all that stuff
together and pull all those uranium nuclei, all those atoms together,
eventually get them close enough so that when they decay,
they knock into each other and create chain reactions and
you would get real fission. You would get you know,
in effect, burning and empowering this thing through fission, because
(38:08):
I guess that's how nuclear bombs work, right, Like, if
you put enough unstable uranium together at some point, it's
gonna cause a chain reaction which will explode. Yeah, And
that's how the sun works, just with fusion. That it's
the energy from fusion is providing the energy needed to
create fusion. That's called ignition, right, And so if the
(38:30):
release of energy then enables the next release of energy,
then you have someone which is self sustaining. And oh really,
you know our son. I thought, like what causes things
to fuse was the gravitational pressure. But it's also you mean,
like the energy pressure from the other explosions. It's a balance, right.
The reason the Sun is not exploding is because of gravity,
and the reason it's not collapsing is because of the
(38:51):
energy pressure, and so in our theoretical uranium star something
similar would happen. Eventually, like gravity would pull this stuff together,
which would increase use the rate of which stuff is
decaying because you know, the decay products are not bouncing
into each other more often. But eventually the energy being
released from fission would balance out the gravity. You get
some like interesting you know, balance there. And I don't
(39:13):
think it would be as dense as our sun. Vision
is not as powerful as fusion, but just release as
much energy. I'm not sure exactly what it would look like,
but theoretically that kind of thing is possible. You just
have to get enough uranium and compress it. Yeah, the
recipe is get a galaxy is worth uranium galaxies isolated
(39:34):
in space and then wait a few million years and
the gravity will bring it together and then they'll will ignite.
And I'm not sure exactly what it would look like like,
how dense it would get, and whether it would be
hot enough to get the surface to be like a
glowing plasma, or whether like other things would take over
before you even got there. But I think theoretically, you know,
it might be possible. Wudn't it be unstable like a
(39:56):
nuclear ball like wouldn't in the chain reaction would run
away and which is explode, right, but you have that
pressure would keep blowing it out, which would lower the density.
The same thing happens in the sun. Right. It's sort
of like self regulates because the hotter it gets, the
more it's pushing out, the less dens it gets, and
that lowers the rate of the reaction. All right, So
it sounds like the answer for Mike is that, yes,
(40:18):
fission stars are possible, but not likely to exist because
they are pretty difficult to make work. That's right, because
the fuel just isn't out there, we think, and we're
also not exactly sure what they would look like, and
take a pretty sophisticated simulation to get like a realistic
answer for what that star would look like. But theoretically
(40:39):
the process is very similar to fusions. You just need
the right fuel and the right conditions. And in the
meantime we are sort of kind of sitting in a
fish and star, right, which is the Earth, that's right.
Fishing is warming your feet, all right? Cool? I think
Mike can sleep will at night? Are you been having
trouble sleeping? Jorge? I feel like all these questions are
now related to like a well being. I'm just fetting
(41:02):
a lot of empathy for these curious people. Well, curiosity
does keep me up at night, but what lets me
go to sleep is knowing that we just need to
think about it and work on it, and eventually we
will get these answers. The history of science is filled
with people wondering about basic stuff that a hundred or
two hundred years later even school children know the answer to.
So eventually our deepest fundamental questions will be you know,
(41:24):
like in story books in the year three thousand and
we talked to preschools. All right, Well, thank you to
Henry Kwan and Michael for sending in their questions, and
thanks to everyone who sent their questions. And it's always
kind of amazing and cool to think about all those
people out there thinking about the universe and coming up
with their questions and even more exciting stumping Daniel. So
(41:46):
thank you everybody for trusting us with your questions, for
taking the time to write in, giving us feedback on
the show, and letting us know what you'd like to
know more about. We want to hear from you, so
please write to us at Questions at Daniel and Jorge
dot com. And thanks to everyone also who has been
leaving us ratings and comments and telling all their friends
about this podcast. We really appreciate it well. Thanks for
(42:08):
joining us, See you next time. Thanks for listening, and
remember that Daniel and Jorge Explain the Universe is a
production of I Heart Radio. For more podcast for my
heart Radio, visit the i heart Radio app, Apple Podcasts,
(42:29):
or wherever you listen to your favorite shows.
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Daniel Whiteson
Kelly Weinersmith
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