March 19, 2020 • 46 mins
Shrink down the the quantum realm with Daniel and Jorge and discover the size of the electron
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Speaker 1 (00:09):
Hey, or hey, you're a visual artist, so I have
a question for you about how you visualize things. Well,
first of all, thank you for calling me an artist.
Cartoonist don't usually get that kind of respect. But do
you mean can I draw my answer? Yeah, maybe when
we upgrade this podcast to a YouTube channel, But until then,
(00:29):
here's my question. What is the biggest distance that you
can visualize that you can sort of see in your mind? Well,
I think anything bigger than the distance between my bed
and the fridge feels like an infinity. I guess maybe
like the biggest distance that I can wrap my head
around would be maybe like the size of the solar system,
(00:50):
you know, Like I think I have a intuitive sense
of that, but maybe anything bigger it just kind of
blows my mind. All right, So then turn it around.
What is the small all this distance that you can visualize?
Probably the width of a thinly sliced banana. Feels like
maybe you should have had a snack before we did
today's podcast. I am Rhammad, cartoonists and the creator of
(01:29):
PhD comments. Hi, I'm Daniel. I'm a particle physicist and
I don't eat bananas no matter how then you slice
them really you're anti banana like you avoid them. I'm
anti bananite, yes on the air. I didn't know that.
Oh my god, how do we even get along all
these years? I don't know if we I can continue
doing this with you anymore. So if you if you
(01:51):
get him in a salad, you picked them out or something.
How far puts banana in a salad? What are you
talking about? You were offending salads? How far this is
anti bananas? Goes go? Daniel, Well, let's see, if I
was dying of starvation next to banana tree, I would
eat some bananas. I'll put it that way. I would.
(02:12):
I see. Oh man, you don't know what you're missing.
But for those of you who are not anti banana,
welcome to this podcast. Daniel and Jorge Explain the Universe,
a production of Our Heart Radio, and banana lovers and
banana haters are all welcome on this podcast because we
only the lovers, because we all share the love of
(02:35):
the universe and the mystery is and the incredible cosmic
questions like how can anybody stand to eat a banana? No? Like?
How big is our universe? And does it all make sense?
Should ever rebody Daniel that bananas are part of the universe.
If you love the universe, technically you love bananas. But
welcome to our podcast, in which we do try to
explore everything around us, including bananas and other delicious or
(02:58):
non delicious items, and explore lane how it all works
to you. Yeah, we try to think about the bigness
of the universe, the limits of space and planets and stars,
but we also like to talk about the small things
in life and in the universe, and and sometimes it
really stretches your mind right to sort of sort of
in one conversation think about how big the universe is
(03:18):
and how also how small things are. Yeah, and we
try to take you on a tour of the sort
of current thinking of scientists. How do scientists think about
this stuff? How do they fit the whole universe in
their brains? Or what do they visualize when they think
about the inside of a black hole? Or how do
scientists think about the very very tiny What does a
(03:39):
particle look like inside the mind of a party goal physicist? Yeah,
because you know, we know that the universe is made
out of tiny little particles, and we like to say
tiny little particles. But I guess you don't often think
about it, what tiny really means. Yeah, we do this
a lot when we think about the quantum realm. We
try to sort of use the ideas we have from
our everyday experience and apply them to particles, apply them
(04:02):
to these tiny little bits so that we can make
sense of them, because you know, you can't see these
things directly, so you have to sort of build a
mental picture, and we try to talk about how they
have mass and charge, and we even give them you know,
labor and spin and other sorts of things that were
familiar with from our world. But you have to wonder, like,
how well does that really work? Is it really relevant
(04:24):
or is the quantum realm just totally alien and we
will never really get our minds around it. Yeah, I
thought we had already decided that everything looks like Lego
pieces down at the fundamental level. They don't look like
little blocks with circles that say Lego on them. Well,
it's easy to do a test. You know, if you
step on them and they cause you great pain, then
they definitely are the shape of Lego pieces. I think
(04:47):
they make round legos too. Now finally to save parents,
But you know, this is all we can do as
humans is we can take the ideas we are familiar
with and we can try to map them down to
the quantum realm to think about this. Yeah, and sometimes
that intuition kind of fails, right, or it breaks down
when you get down to that quantum realm, that quantum level, right,
our ideas of what something is, or how solid something is,
(05:12):
or what shape it has, and it all sort of
breaks down into kind of mathematical goop right down at
the quantum. I think it has a little bit more
substance than mathematical GOOPI gloop, but really it's a bit
more No, it's a bit more poetic than mathematical sometimes
(05:32):
because well, we try to draw connections, like we talk
about quantum spin, and we fully admit that these particles
are not actually spinning, but they're doing something that is
very much like spin. It has a lot of similar characteristics,
and so we draw this analogy. And I think this
is one of the most beautiful things about physics, is
trying to describe the unknown in terms of the known.
(05:53):
You know, that's what languages, that's what art is, that's
what that's what it means to explore the universe is
to express it in a way that we can understand it,
and so that's all we can do. Yeah, are you
saying you don't understand google Goog? I'm saying googly groop
suggests some lack of understanding or nonsense, whereas in its
place there are some elegant intellectual structures to guide your mind.
(06:17):
I see, you know, potato, potato again, theoretical structures, googly goog,
it's all, it's all, you know, different names. But so
to the other podcast, we thought we would take a
trip down to that quantum level and kind of think
about a particular, you know, object that I think we're
all familiar with, and to sort of challenge our understanding
(06:38):
of what it looks like and what shape it has
and most importantly, what size it has down at the
quantum realm. And this is something that I have struggled
with as a particle physicist, just trying to visualize, just
trying to conceptualize it. How do I put this in
my mind? How do I think about this so I
can get some intuition right? And so today we'll be
tackling the question how big is an electron? Or how
(07:08):
small is an electron? Oh? Man, is this another potato
po typle thing. It's big and small depending on which
country here. The representatives of the Electron Union prefer to
be called big rather than small. Oh, I see, But
what does the electron itself prefer? Does it see itself
as a as a big or a little? Interview with
an Electron speculative fiction novel by J H winner of
(07:32):
the Nobel Price in literature and physics at the same time.
But yeah, you know, electrons are everywhere. They're one of
the three fundamental particles that make up everything that we are,
that you are, That planets and stars and galaxies and
dust are made out of um. And so it's an
important particle. And it makes yourself phone work, which without
which you would probably not be listening to this podcast. Yeah,
(07:55):
and it sort of sits at the frontier of particle physics.
Our goal is to explain everything in the universe in
terms of the smallest bits and pieces, the tiniest, roundest
lego pieces anywhere, And as far as we know, these
are the smallest bits. And so we wonder, like, is
it made of something smaller? How small is this thing? Anyway? Yeah,
(08:15):
what's the size of an electron? I guess that's a
question we haven't really talked about before. We just sort
of talked about electron and what they can do and
what they do, and we know they're small. But I
guess the question here is how small it is? Or
how big is it? Not? How big isn't it? Yeah,
And like with many of these mappings to the quantum realm,
I'm pretty sure you're going to be dissatisfied with the
answer because did you misname something again? Is it not
(08:40):
really called? Is it like an electron? Not really an electron? Well,
I don't want to give away the end there, you'll
have to stick around for another half hour. Well, this
is a question that, as always, we were wondering how
many people out there had thought about or wondered about
and what they knew about the answer to this question. So,
as usual, Daniel went out there into the wilderness of
the streets of Irvine, California and ask people how big
(09:03):
they thought an electron is. I like the way you
make it sound dangerous, like I'm hacking my way through
the jungle. I think talking to perfect strangers, it sounds
terrified to me. Well, here's what people had to say.
But before you hear these answers, think to yourself, what
would you guess is the size of an electron? Very small?
I know, like a couple of billion Adams can fit
(09:25):
on a period in in a book, So an electron
is Chillian quadrillion. I don't know. Sudden thinkers like small,
like smaller than that. Best guys like like a hundred
of a nanometer ten to the minus sixteen. Well, I
guess it's when it's a way function falls off? Is
(09:46):
one over eight or something like that? Is that how
we want to call it? What's thirteen point six e
v s and nanometers that it does red stuff? So
a couple d nanometers? Let's doing that? Also, no idea,
best es not that big tend to the negative on
all eleven or twelve or something like that. Like all right,
(10:09):
some pretty I feel like, pretty educated answers, Like some
people were talking about electron volts even I like the
guy who says smaller than a centimeter, like yeah, that's
that's true, yes and also correct, Yes, it's definitely correct. Um. No,
we shouldn't make fun of these people. They are giving
us their time, their and their energy, and so it's
(10:30):
fun just to just to know what people have in
their minds. And I think one of the common answers
is like, tend to the mind is a pretty big number.
But yeah, know I thought they were pretty I guess
you're at a at a university, so maybe a lot
of these folks just think in physics or something. But um,
you know, if you ask me, I don't know if
I would guess with exact figures or units. Well it's
(10:50):
interesting because if you ask me, I don't know what
I would say. It's a tricky question. Even what is
the meaning of the question, Like what does it mean
for the electron to have a side? Is? So it's complicated.
So someone interviewed on you on the street and ask
you this question, you'd be like, let's sit down for
a couple of hours, let me pull out my white board,
(11:11):
thank you for asking that question. And you see the
panic in their eyes. I've been waiting all my life
for perfect strangers. They would feign a phone call and
run away quickly. All right, Well, let's get into the
trying to answer this question. And I guess the first
thing is is that you're telling me is that this
is even Um, it's kind of almost a philosophical question.
It's like a tricky question in itself to ask what
(11:32):
is the size of an electron? Yeah, And you have
to be really careful about what you're doing. When you're
asking a question that you're used to asking about macroscopic
stuff and then applying that to microscopic stuff, you have
to be really careful about what you mean and what
exactly it is you're trying to learn. You know, like
when we think about a ball moving through space, we
can talk about its velocity. Cool, But when you want
(11:55):
to talk about the velocity of an electron, it's more
complicated because it doesn't have like the same kind of
half and so it's philosophy changes, and sometimes you can
know it, sometimes it's unknown, and so you know, there's
an analogy you can make there, but you have to
be careful about exactly what you're asking. And the same
is true when you ask about the size of something
super duper tiny, right, and and especially when you ask
(12:17):
about the size of a single thing, right, Like what
is it? What does it even mean to ask about
the size of anything? Is it like how much space
you occupy? Is it like the my longest dimension? Is
it the distance between you know, one and one side
of me to the other side of me. I think
that's it. I think it's the distance between your edges.
(12:37):
And so you have a size if you have edges
that don't touch, right, if you have if there's a
meaning to like there being a left of view and
a right of view, and your size is the distance
between them. You know, we have a meter stick, how
big is it? Well, the left side is one meter
from the right side. So that's sort of makes sense, right,
And this this all sounds, you know, obvious, but it's
(12:57):
going to be important when we get to the quantum
realm to be thinking about it in the same same
sort of set of ideas. Right, Yeah, I guess you've
got to think about what makes it a thing and
when is it stopped being a thing? And then then
you calculate kind of the distance between the edges of
what is and what is not a thing. Yeah, And
so you answer the question like what a size mean, Well,
(13:18):
it's the distance between the edges and that immediately, but
you can see you to the other question, what is
the edge, Like what is the edge of a meter
stick or the edge of a banana? How do you
define where that stops? And that's not so easy. Oh man,
you just make me imagine it endless banana and I
salivated a little bit. That's a whole universe to you,
right there. Man, maybe the whole universe is just one banana.
(13:40):
We are all just banana nos in a banana. We
should start that in the restaurant. You know, Olive Garden
has the endless bowl of salad, endless bread stick. We
can we can start selling the endless banana. But anyways,
so where is the edge of the banana? Right? You
would think, oh, I'm looking at it, I can tell
where it stops. And you either you poke it or
you're just looking at it. It sort of gives you
(14:00):
a sense for like where the edges. It doesn't have
a fuzzy edge, like it stops the all the atoms
that make up the banana are kind of stuck together,
and at some point there aren't any more of the
atoms that make up the banana. Yeah, although, if you're
zooming close enough right, everything that's not an absolute zero
is has a bit of a fuzzy edge, you know,
it's like boiling off atoms. Like the reason you can
(14:21):
smell banana is that there are volatile molecules on it
that are always leaving and so zooming close enough, and
there's there's a bit of a fuzzy edge there. But
still you can like take a stick and you can
poke the banana with your tiny stick and you can ask, like,
when does the banana give me resistance? Or is the
edge of it is sort of like, you know, where
is it push back? Okay, so that that would be
(14:42):
the edge of like an object microscopic option you're saying.
It has to do with when it no longer interacts
with you in the same way as the rest of
the banana. Yeah, And there's an important idea there, I think,
which is it's not where the stuff of the banana ends,
it's where the bananas forces push back. Because you know,
the banana itself is mostly made of these we'll talk
(15:03):
about in a minute, but time much smaller particles, and
the stuff of the banana, the thing that gives it
its volume is the forces. Right, If there were no
forces between these particles, they will collapse to a much
smaller pile. Like you just made a pile of all
the atoms inside the banana, it would be almost invisible.
Most of that volume comes from them spacing each other.
(15:23):
Out by the forces. So it's really the forces, the
pushing back that gives the banana it's volume and therefore
its size. I see, you wouldn't measure it as between
the center of the rightmost atom of the banana to
the center of the leftmost atom of the banana. You
would be you would extend that a little bit to
include like when that atom starts pushing back another adom
(15:45):
that tries to poke through the banana. Precisely because if
you bring your stick nearby, then the farthest, the most
extreme atom and your stick is not going to touch
the nucleus of that atom in your banana. They're going
to push against each other before they touch. And so
that's what I think of sort of the edge of
the banana is that force field that sort of protects
it from you know, external forces. Okay, so you're saying,
(16:07):
as a physicist, you would define the size of something
as as the edges of it, and the edges you
would define is when they start pushing other things from
going through it. Yeah, So really it's more about interactions
than it is about matter itself and particle physics, we
think a lot about particles and forces, matter and interactions.
(16:28):
And I think the size of something really depends more
on its interactions then on the stuff that's inside of it.
And that makes sense because if you want to know
the size of something, you want to know it for
a reason usually right, like you want to see if
the banana fits inside of a special you know, banana
carrying case that you aren't designing. You need to know,
you know, not when the set where the centers of
(16:49):
the atoms are, but you want to know, you know,
if you can fit the banana inside the case. That's
exactly it. But it already raises some problems, like what
if you had a blob of dark batter the shape
of a banana, how big is it? Well, if you
can't really interact with it, if you could like put
your finger through it, then you know, does that mean
(17:10):
that it's a banana shaped and blob of dark batter
is smaller? It doesn't have a size maybe even boy. Yeah,
so it gets it gets tricky pretty quickly. This thing,
which which we thought was simple is actually turns out
to be kind of subtle. Yeah, it's feel back the
answer to this question and also get into how big
an atom is, and then we'll get into how big
an electron it is. But first let's take a quick break,
(17:45):
all right, Daniel. So it seems like the question of
how big something is is kind of fuzzy in itself,
and so maybe a good way to kind of tackle
it is to start with the next level down from
a banana, which is like how big is a is
one of the atoms in the in the banana. So
remember that we decided that if we're going to talk
about the size of the atom, we're not going to
(18:07):
ask where is the stuff inside of it? We're gonna
ask where does it push back when it's poked? And
to figure that out, it's helpful to sort of imagine
a whole pile of atoms packed together. Here you have
you like imagine the banana is sort of like a crystal.
You know, it's like closely packed atoms of the banana.
And here it's determined again by the interaction between them,
Like how closely packed are they depends on how much
(18:30):
they resist being squeezed together. And in this case, for
an atom, it's you know, for banana. For other stuff,
it's a it's pretty small. It's like you know, fifty
to a couple hundred trillions of a meter. Is what
how you you would define how big anatom is. Yeah,
that's like this the separation between the center of one
(18:51):
atom and the center of another atom. Depending on the material,
and different things can sort of pack more tightly together
than other things. Like hydrogen, you can squeeze it down
to like thirty trillions of an atom between protons. But
if you're packing lead together, for example, it's almost two
d trillions of a meter between sort of the centers
(19:12):
of the nuclei. I say, it's it's like if you're
trying to measure the size of a bunch of marbles.
You would stick him in a container and see how
many you can sort of cramp together, and that kind
of tells you the size of each marble. Yeah, the
distance between the centers of the marbles. There you pack
them as closely as you can, and then you measure
the distance between the centers of the marbles. Is that
actually sort of because you know, when I think of
(19:33):
an atom, I think of like, um, you know, like
the popular culture drawing of an atom, which is like,
you know, little balls in the center and then electrons
flying around in orbit. You know, you know, and I
know that you know, they're actually like electron clouds. But
even the clouds have sort of a size, right, they're
drawn as little balloons that stick out of this center.
(19:55):
Is the size is the packing size that you're talking about,
like how many you can crime in banana, the same
as the size of those like electron clouds. Yeah, it's
very closely connected. And for a reason, those electrons are
the reason that the atoms don't pack more closely together,
Like you bring two hydrogen atoms near each other. It's
the electron clouds that determine how closely they get together
(20:18):
because they form like a covalent bond and make an
H two or something like that. And so it's those
electrons that determine the interactions between the atoms and determine
their spacing. And it's when those two things start overlapping,
is when they can no longer really get closer together. So, yeah,
the size of the electron cloud is very closely connected
to the size of the atom. It really is what
(20:39):
defines it. They're always interacting, right, no matter how far
apart there are, Like if I had a hydrogen atom
here and you had a hydrogen atom and Jupiter. Technically
they're sort of repelling each other, right or and or
attracting each other or not. They definitely do feel each other.
You're write the the extent of the electromagnetic force is infinite,
So there are electrons in Alpha Centaur that are pulling
(21:01):
on you or pushing on you, or depending on whatever
they're doing, technically touching you. Right, you're being touched by
an alpha centaur right now. I just got chills down
my spine a little bit to the left. Please, yes,
thank you. Crash that is that I've had. Yeah, well
it's a tricky concept. You're right. If we're going to
(21:21):
define size by sort of how you were responding when
you get poked, then you're right. You're being constantly poked
by everything in the universe. Well, even the stuff like
a build B zillion nine years away. Yeah, it is everything.
Everything in the universe is feeling you. Although you know
there's a time delay there, so the stuff in Alpha
Centauri is only feeling. Stuff is feeling where we were
(21:43):
a long time ago as a separate issue. So my
size depends on time as well. Jeez. But you know,
those those things are pretty negligible, and so you can
think about like when these things really have an effect
if you probe if you shot an electron at um
hi'd gin atom, when would it deflect the electron? And
if you shot you know, a meter to the right,
(22:04):
it wouldn't change the path of the electron really at all.
It would, but just it would be very little, It
would be very little bit negligible. But then when you
you know, hit it right on, then it's going to
bounce right back. And and so you can use that
to sort of get a sense for what is the
meaningful sort of charge radius of a particle. And you're right,
it's there's no crisp edge there. So there's a small
(22:26):
complication there also because it turns out that the size
of something depends on not just what you poke it with,
but how hard you poke it. Like, if you poke
an atom very gently, it'll seem bigger because you'll notice
smaller deflections further away. If you poke it very hard,
it will actually seem smaller because you'll overpower the electrons
(22:48):
and the outside and only see the nucleus on the inside.
There's no point at which it goes to zero though,
you're right, right, yeah, So it's it's kind of fuzzy
and maybe kind of arbitrary, but you're saying, it's like
when when you would actually fee you the force of
that electron, that's when maybe you would say, all right,
it's sort of impinging on it, which means it's sort
of bumping up against it. Mm hmm, And it's not
totally arbitrary. Like when you squeeze atoms together, they settle
(23:11):
in at a certain distance from each other, so that
totally tells you what the equilibrium location is for for
the distance between atoms, and that I think is a
reasonable way to define the size. But you know, you're right,
you have to think about, like what am my meaning
by size in this context? In this other context? This
basic thing we think about like should be obvious to
talk about is it turns out to have a lot
(23:32):
of wrinkles to it, all right, So that's kind of
how you would define an atom is when it starts
to push back another atom, and how much when you
crow them inside of a box, you know, what's the
natural spacing that they have between them? And it's you're
saying sort of related to those electron clouds, which is
how kind of how far away the electron goes from
the nuclei right, Okay, so that's a that's an atom um.
(23:56):
But I guess it gets strict when you talk about
individual particles. So let's go down one more level to
the proton inside of the nucleus. How big? How how
big would you say a proton is? This is a
wonderful question. And you know, if you're breaking open the atom,
if you're shooting electrons at the atom, it's going to
get repelled by the electrons on the outside of it.
But if you give them enough energy, then they can
(24:17):
sort of penetrate through there, and then you can start
to probe the proton inside there, and you can ask, like,
how big is this thing? And so we do that exactly.
We shoot electrons at protons or hydrogen atoms or or
it doesn't really matter if the electron is there anymore,
because the probe we're shooting with has so much energy,
and we see where does it bounce back and where
(24:37):
does it sort of stop bouncing back, and that gives
us a sense for how big the proton is, and
so we actually have a number for that. But it's
tricky because the proton is also made out of things
inside of it, sort of like the atom itself. It is.
Protons are made of smaller bits that are slashing around
inside of it. Those are the corks. But remember that
we're trying to define the size of an object, the
(24:59):
proton this case, not by where the stuff is inside it,
but where it pushes back. And the corks hang out
together and push back against the other protons. So if
we use our definition, it's the distance between the protons
that's going to determine the size of the protons. And
that's connected, of course to how the corks are arranged,
(25:19):
how they're happy to be inside the proton. The proton
is sort of like a cork atom. I See if
they were comfortable being a mile apart, you know, like
if you try to split it more than a mile
or squish the more of them out, they would prefer
to be a mile up apart from each other. Now,
you would say the size of those two electron at
courts is about a mile. So the size of the
proton that's that's made up of those corks, yeah, it
(25:40):
would be about a mile. But you know, we have
nuclei and they have got protons and neutrons inside of them,
and each one is like its own little particle. They
get squeezed together, but they hang out. They keep their
own little particle nature, and so it's just like packing
marbles together. You can ask about like the distance between
the center of one proton and another, or a proton
and a neutron. That's what we think of as the
(26:01):
size of the proton. How much can you pack in
the quarts that are inside of the proton? Yeah, and
that's a really crazy number. That's like one quadrillionth of
a meter. It's a really small number. Uh. And that's
smaller than a nanometer for sure. It's smaller than a
centimeter as well. It's smaller than a mile apparently as well. Um,
(26:24):
so that's pretty small. That's pretty small. Yeah, Like, how
how big is that in relation to like the size
of an atom. Well, an atom is you know, like
ten to a hundred ish um trillionth of a meter,
So this is one quadrillionth of a meter, So it's
like one ten thousands or one hundred thousands the size
of an atom. So it's very small compared to the atom.
(26:47):
Bare to the electron radius, the proton is super tiny. Okay,
wait wait, so um, we have an atom and how
about the just the nucleus of the atom. How close
together are those protons and neutrons in the nucleus packed together?
Those are very tightly packed together. And and again remember
that's because that's sort of how the size of the
proton is determined. It's like how do those things cluster together?
(27:08):
And so the size of like if you have the
nucleus of an atom with you know, a hundred protons
and neutrons in it, it's not that much bigger than
one protonomy. It's like packing above those marbles together. So
it's going to be ordered magnitude quadrilliants of a meter.
Oh wow, so the new And that's why they say,
like the anatom is mostly empty space because you know
(27:29):
what you would say is the size of it. Actually
the nucleus is like this tiny little bit of it inside. Yeah.
And the way that they probe this is two different ways.
One is they shoot an electron at proton. But sometimes
also they just look at an atom. They just watch
an atom sitting there. It's got a proton and an
electron and the electron is whizzing all around. And sometimes
(27:52):
this is super weird. Sometimes the electron goes inside the proton,
like in a quantum mechanical way, or like it actually
goes through what's the difference quantum mechanics is reality, dude, um,
Like if you were to you know, I mean, like
if you were to open the true Dinger's box and
you would you would suddenly find it inside of the news. Yeah,
(28:13):
the electron in one of its states has non zero
probability density to be inside the proton. And when this happens,
it's sort of like partially cancels some of the charge
pull of this thing because you have the electron now
inside the positive atom and then it escapes. But depending
on the size of the proton it escaped, this happens
(28:34):
more or less often, so you can measure like how
often the electron is inside the proton, and that tells
you how big the proton is, because the bigger the
proton is, the more often this happens. So this is
another way we sort of get a sense for how
big is the proton. I see, using like probability, like
you throw a bunch of darts at it, only sometimes
(28:56):
you hit hit the proton. Then that sort of tells
you the size. Yeah, exactly, And that's actually the most
sensitive test. Basically using the hydrogen's own electron, like pass
it through the proton and give you a sense for
how big it is. It's crazy. Well, all right, so
a proton is about you're seeing one ten thousands of
the size of a typical atom. That's pretty small, because
(29:16):
a pretty small. So alright, so let's get there. Let's
get down now to the last level, which is how
big is an electron? And I imagine that's going to
be even smaller, but we'll get into that, but first
let's take a quick break, all right, Daniel. So now
(29:45):
we're down to one of the fundamental particles, the electron,
and we're asking the question how big is it? Or
how small isn't it? Or how big isn't it? Amount
of negatives here, um and so, And I guess what
we're talking going to talk about. It sort of applies
to quarts as well, right, because we're now talking about
(30:06):
single particles, not like clusters of particles. Yeah, and remember
that our theory is very hierarchical. We start with matter,
and then we go to molecules, from molecules to atoms,
from atoms to protons and electrons, and then to quarks
and electrons, and we're sort of have shells inside shells
inside shells, and so this is sort of our current
level of knowledge, and we can ask like, are these
(30:27):
particles that we see, um, are they the smallest possible thing?
Or is it possible there's something else inside them? So
you're right there, quarks and electrons are sort of as
far as we've gone, and so in some sense, asking
how big are they is asking are they the end?
Are they the tiniest, smallest possible thing? Or they possibly
made of something smaller? Oh? I see, because if you
(30:48):
can split them, that means there's something smaller inside. I
guess that's pretty obvious. And that's for you. That sounds
deep and it is deep, but it's also kind of obvious,
like if you can break it into smaller pieces, then
it's there were made of something else. As far as
we know, quarks and electrons are not yet made of
something smaller. But that doesn't tell you necessarily how big
they are. Right, they could be the smallest possible thing
(31:10):
and still have a finite size. Right they could be um,
the legos of the universe. Lego. Yeah, it could be
the smallest lego you can have, but um, that can
be smaller, smaller, big, that could be smaller big, And
that's fascinating when you learn a number about the universe. Like,
let's say we somehow proved that quirks and electrons are
not made of anything smaller. They have the smallest lego blocks,
(31:31):
and we measured their size, Then we'd we'd know something
really deep and basic about the universe, like it's made
of legos this size, and you have to wonder, like, well,
why that size and not something else? What does that
tell you about the universe to know that fundamental fact? Yeah?
Did you know there are legos that are smaller than
the single unit lego? What? Like you you would think
(31:52):
the smallest lego is just like one square with one
circle on it, right by saying people have smashed the
legos together and make some legos covered the constituent pieces
and legos. No, yeah, they make uh this is kind
of weird but uh probably not consequential. But um, they
make smaller pieces. It makes pieces that fit inside of
(32:12):
the whole that some of the single circle lego pieces
have inside. Oh my god, you have just violated the
standard model of legos. Noble price. Please you've got the
prize from that one. Anyways, Um, so, yeah, so let's
talk about how big an electron Isn't let's use that
as our single particle example. And does it even make
(32:34):
sense to talk about the size of a single particle, Daniel,
It's hard to talk about the size of a single
particle if you haven't measured the stuff inside of it.
Because we've talked about the size of atoms and protons
based on like how happy this stuff inside of it
is to be next near each other, like how closely
does it pack? So for a fundamental particle you have
to go back to like the poking it and be like, well,
(32:57):
if I poked an electron with a stick, where were
pushed back? But that's sort of unsatisfying to me. Couldn't
can't I just you know, pack a bunch of electrons
in a in a glass jar and see, wouldn't that
tell me sort of the size of it, Like how
comfortable an electron is to another electron or to a proton.
Wouldn't that sort of tell you this sort of the size,
(33:17):
just like we did with the marbles and the atoms. Yeah,
that sounds like a really fun experiment. I want to
take like a gas of pure electrons and squeeze it
down together and see what happens. The problem is that
there's not like a clear answer, like the heart do
you squeeze the closer they get together, it's not like
an equilibrium like with protons or with atoms, because these
are all just negatively charged particles. There's no chill state
(33:39):
where they're like, hey, you're there, I'm here. All is good,
and so instead you want to like take them and
like poke them, like, well, if you poke them with
an electron, then they bounce back for sure, But what
if you poke them with neutrinos then they don't bounce
back at all, Or what if you poke them with
dark matter? Then they don't bounce back, And so you're
back to this like fuzziness of like you know, if
(34:01):
it depends on how it's pushing back, then it depends
on what you're poking it with. And then size isn't
something that's like inherent to the object. It's about the interaction,
which means it depends also on the thing you're interacting
it with, which is so frustrating. Oh, I see what
you're saying. Like if I had a cloud of electrons,
you could maybe talk about where the cloud is, and
(34:21):
where the cloud isn't, where the electors are and where
there aren't. But with one single electron, it's hard to
say where it ends. It's hard to say where it ends,
like is there a left side to the electron and
the right side to the electron? Are those things even
the same thing? Because it depends on what you you're
trying to touch it with, right, Like, if you're trying
to touch it with another electron, it would maybe repel
(34:41):
at a certain distance, But if you try to poke
it with a proton, then it would maybe attract at
a different distance. Yeah, well not so much electron versus proton,
because they both feel the electromagnetism. But what if you
used a different force, if you use like the weak
nuclear force, or if you used you know, gravity, or
if you used electromagnetism, is them than the size that
you would get from electron is different. And we're turning
(35:05):
to a neutrino. An electron has those eyes. It doesn't like,
I don't care, Like the neutrino doesn't care. A neutrino
would pass through a cloud of electrons and have a
much lower chance of interacting than another electron would, like
it wouldn't even know it's there, yeah, or dark matter, right,
pokeing a pile of electrons with a stick of dark matter,
you're gonna get almost no interactions, or maybe no interactions.
(35:28):
We don't even know about dark matter. And this is
the problem. It makes sense to define size in terms
of interactions, like where is something pushed back, But it
also is troublesome because then it depends on what you're
pushing on it with. So that's kind of a problem
in defining the size of an electron because it depends
on what you poke it with. So then we try
something else. We say, well, let's think about it like
quantum mechanically, Like we've talked about where the electron is,
(35:52):
and it's defined by like it's quantum mechanical wave function,
and you know you were talking about like those balloon
shapes where the electron is. You know, it's the sort
of the most you can localize an electron, Like what's
the size of that quantum packet? You want to think
about it like as a tiny quantum object. That's like
another way to try to grapple with it because their
probability curves right, Like you know where the cloud is
(36:12):
fuzzy tells you that the probability that the electron is
there is small, but where the cloud is kind of thick,
it tells you that there's a high probability that the
electron is there. But that doesn't really give you any
insight because that size can be almost anything. It depends
on the uncertainty principle. If you know almost nothing about
the velocity of the momentum of the electron, then you
(36:34):
can know exactly where it is, which means it has
like zero that quantum mechanical packets zero with And on
the flip side, if you know everything about its velocity,
then it's packet is infinitely wide, like exists everywhere in
the universe simultaneously have like a universe sized electron. So
that's intellectually not that satisfying either. But what if you
(36:57):
assume an electron is just standing still, like when you're
to measure your kid how all they are and it's
impossible because they keep moving. But what if you can
get it to stand still? Oh wouldn't what would that happen?
Would you be able to then get a pretty accurate size.
If you're measuring the velocity of the particle, you're getting
it to stand still has no velocity, and you say
it has zero velocity, then it has infinite size because
(37:19):
you can't know the product. Remember the product of the
position and momentum uncertainty has to equal a certain number.
And so if you're narrowing down the speed of the
electron really really well, that means you don't know anything
about where it is. It's an infinite plane. Wave size
is only distance, whereas you know in particle physics, distance
(37:40):
is kind of intertwined with time as well in velocity.
But then on the flip side, if you say I
don't care at all about how fast it is, I
just want to know where it is, then you can
localize it as much as you want. You can make
it infinitely narrow. And so that also doesn't give you
any sense of like the size of the electron. So
strike to we can can use poking or are quantum mathematics.
(38:01):
So does that mean that the electron has no size,
that it's impossible to define the size of an electron.
It kind of does currently. I mean in our theory,
the way we actually use it is we assume the
electron has no size at all, It has zero volume.
That it's just like a point in space. The left
is the right, the top is the bottom, the back
(38:22):
is the front. There's no extent to it at all.
It's sort of mathematically and and because of all the
things we just talked about, I guess that that's true. Yeah,
you can't measure the size of an electron. It doesn't
make any sense to think about it. Yeah, in our theories,
we just put zero because we assume that there's nothing there.
We have no way to really see the size of
the electron. But you know, we do continue to try.
(38:43):
We do smash particles at the electron, hoping that we'll
see a break open, hoping that we'll see other little
particles come out of it. But I guess getting back
to the size of the electron itself, um, I mean,
it's not like it has no size because it's it's
not a mile wide, Like, would you even say that
the electron is all electrons are a mile mile wide?
(39:05):
I don't know what to say for the size of
the electron, you know, And that's why I predicted, I
think correctly, that you'd be unsatisfied with Oh my god,
it's not really you can't tell the future, can Yeah, well,
I can in this case, like I think the way
I think about it currently is as a point, But
I also know that that makes no sense because like,
(39:27):
how do you have something that has mass but has
no volume because then has infinite density, which is nonsense,
right is it? Electrons have mass, they have mass, and
they have charge, Like where does that charge go? Where
is it in the electron if it has no volume.
We're just used to thinking about stuff as having sizes
having volume, So to imagine that the basic building box
(39:48):
of the universe themselves are of zero volume is really weird.
But I guess maybe you know that that's the theory
of it. But practically speaking, I mean, we can talk
about what's what's practical to you and me is like
electromagnetic forces, right, you know, And it doesn't make sense
in terms of neutrinos are dark matter, but kind of
what's practical electromagnetic forces? And so couldn't we sort of
(40:10):
maybe give a practical size to the electron because of that,
like like what's the closest to electrons in one atom?
How close can they get to electrons in another atom?
Wouldn't that give you a general size? Yeah, and we've
done that we like pounded electrons near each other and
try to get them as close together as possible, And
so far we haven't found a limit, Like, there's no
(40:33):
point at which the electrons will not get closer to
each other. And so far we've gotten down about ten
to the minus twenty meters. And you do that by
shooting really high energy electrons at other electrons and try
to get them really close together. So that's as far
as we could tell. We can't tell the difference between
the electrons have no volume, and they have some volume
(40:55):
that's smaller than ten to the minus twenty. We can't
tell the difference. So far. They look like their point like,
but we have some sort of limited resolution there in
our ability to probe. So what happens if I the
whole universe was just like a proton and an electron,
I guess the electron would orbit the proton. That's what
hydrogen is. Yeah, The size the hydrogen comes from their interactions. Right,
(41:15):
Most of the volume of all the stuff in the
universe comes from the interactions, not from any actual volume
of the particles that make them up. All right, Well,
you're right, this is very unsatisfying. Anim Well, that's satisfying
to me that at least I was right about that.
But it's a it's a really fun puzzle because I
think it's interesting to try to grapple with the quantum
(41:36):
realm and try to understand what are the limits of
our ability to map these concepts size and mass and
charge and velocity down to these tiny particles that, in
the end are the reality, are the truth about our universe. Yeah,
And I think it's interesting how, you know, you sort
of put it that it's all about the interactions, you know,
And it's hard to think about an electron not having
(41:57):
like a surface or you know, an st where it's
no longer an electron, And it all sort of depends
on what you're trying to look at it with, you know,
Like if you're trying to look at it with neutrinos,
then you wouldn't see anything at all. Yeah, But if
you looked at it with the electrons, it would feel
like a certain size maybe. Yeah. And this is connected
to some of the other puzzles we talked about, like
(42:17):
does the electron actually spin? We know that it's either
a point, in which case it doesn't make sense for
it to spin like a point literally cannot spin, or
that it's super tiny. But if it's super tiny and
it has a surface, then it's spinning so fast that
that surface is moving faster than the speed of light.
So at some point, like it doesn't even make sense
(42:38):
for it to have a non zero size. At some point,
nothing makes sense, Daniel, life is meaningless, And that's usually
about forty five minutes into every episode. The incredible thing
is that we can understand it at all, That we
can take these ideas from our everyday experience of like
eating bananas and throwing balls around, and then it can
(42:59):
give us any side into the microscopic. You know that,
because the microscopic is so weird, so alien, it's incredible
it works at all that I even have a job.
But yeah, but that's the thing it was. We don't
understand it, but yet at the same time we're able to,
you know, predict it and describe it with math. But
that doesn't mean we understand it, right, That's what understanding is.
(43:19):
As far as I know, I don't know any deeper
level of understanding. When you pass it off to the
philosophers and you can ask them, like, you know, what
does it mean? Man? But in the end. What we're
trying to do is physicists is just sort of describe
accurately the world we see around us, build a model
in our heads that makes sense, describe all this unknown
in terms of the known. That's that's all the understanding
(43:40):
we can hope for. Well, I guess what I mean
is like at some point we thought the proton was
a proton, and we had to math to describe it,
and we thought we understood it. But then then it
turned out we that we there was more to the
proton than we thought, and we didn't actually understand the proton.
It was made out of quirks, for example. So I
feel like, you know, you have a mathematical di ccription
of stuff, but you don't know if you're really understanding
(44:03):
it to the fundamental level. And all of these mathematical
descriptions they work up to a point. Like your idea
thinking about a proton as a fundamental particle as a
point particle that mostly works. It works unless you get
up to really high energies, energies where you can see
inside the proton, because the energies are greater than the
bonds that are holding the proton together. And so as
(44:24):
we keep pushing to higher and higher energies. We're looking
deeper and deeper into the real truth the smallest scales
of the universe. And that's what limits how small we
can see is the energy with which we probe it.
And that's why, like building a bigger super collider would
let us maybe see whether the electron had bits inside
of it. Yeah, keep funding physics is hey, I'm on message.
(44:46):
If nothing else, keep sending those checks. Please, if you
have to pick between donating to bananas or fundamental physics,
you know where I stand on that. Bananas, right, because
bananas are made out of fundamental partners. All right, Well,
we hope you enjoyed that, And maybe the next time
you take a bite out of a banana or your
(45:07):
fruit of choice, maybe think about what it actually means
to take a bite. I feel like we've thrown everything
into question now, Daniel, Like, what does it even mean
to take a bite into When my teeth end and
when does the banana begin? I don't know, but every
banana you've ever eaten is made out of zero volume particles.
Chew on that and think about it until next week.
Thanks for joining us, See you next time. Before you
(45:35):
still have a question after listening to all these explanations,
please drop us a line. We'd love to hear from you.
You can find us at Facebook, Twitter, and Instagram at
Daniel and Jorge That's one Word, or email us at
Feedback at Daniel and Jorge dot com. Thanks for listening,
and remember that Daniel and Jorge Explain the Universe is
a production of I Heart Radio. For more podcast from
(45:57):
My Heart Radio, visit the i heart Radio app, Apple Podcasts,
or wherever you listen to your favorite shows. Yeah m
Hey, or hey, you're a visual artist, so I have
a question for you about how you visualize things. Well,
first of all, thank you for calling me an artist.
Cartoonist don't usually get that kind of respect. But do
you mean can I draw my answer? Yeah, maybe when
we upgrade this podcast to a YouTube channel, But until then,
(00:29):
here's my question. What is the biggest distance that you
can visualize that you can sort of see in your mind? Well,
I think anything bigger than the distance between my bed
and the fridge feels like an infinity. I guess maybe
like the biggest distance that I can wrap my head
around would be maybe like the size of the solar system,
(00:50):
you know, Like I think I have a intuitive sense
of that, but maybe anything bigger it just kind of
blows my mind. All right, So then turn it around.
What is the small all this distance that you can visualize?
Probably the width of a thinly sliced banana. Feels like
maybe you should have had a snack before we did
today's podcast. I am Rhammad, cartoonists and the creator of
(01:29):
PhD comments. Hi, I'm Daniel. I'm a particle physicist and
I don't eat bananas no matter how then you slice
them really you're anti banana like you avoid them. I'm
anti bananite, yes on the air. I didn't know that.
Oh my god, how do we even get along all
these years? I don't know if we I can continue
doing this with you anymore. So if you if you
(01:51):
get him in a salad, you picked them out or something.
How far puts banana in a salad? What are you
talking about? You were offending salads? How far this is
anti bananas? Goes go? Daniel, Well, let's see, if I
was dying of starvation next to banana tree, I would
eat some bananas. I'll put it that way. I would.
(02:12):
I see. Oh man, you don't know what you're missing.
But for those of you who are not anti banana,
welcome to this podcast. Daniel and Jorge Explain the Universe,
a production of Our Heart Radio, and banana lovers and
banana haters are all welcome on this podcast because we
only the lovers, because we all share the love of
(02:35):
the universe and the mystery is and the incredible cosmic
questions like how can anybody stand to eat a banana? No? Like?
How big is our universe? And does it all make sense?
Should ever rebody Daniel that bananas are part of the universe.
If you love the universe, technically you love bananas. But
welcome to our podcast, in which we do try to
explore everything around us, including bananas and other delicious or
(02:58):
non delicious items, and explore lane how it all works
to you. Yeah, we try to think about the bigness
of the universe, the limits of space and planets and stars,
but we also like to talk about the small things
in life and in the universe, and and sometimes it
really stretches your mind right to sort of sort of
in one conversation think about how big the universe is
(03:18):
and how also how small things are. Yeah, and we
try to take you on a tour of the sort
of current thinking of scientists. How do scientists think about
this stuff? How do they fit the whole universe in
their brains? Or what do they visualize when they think
about the inside of a black hole? Or how do
scientists think about the very very tiny What does a
(03:39):
particle look like inside the mind of a party goal physicist? Yeah,
because you know, we know that the universe is made
out of tiny little particles, and we like to say
tiny little particles. But I guess you don't often think
about it, what tiny really means. Yeah, we do this
a lot when we think about the quantum realm. We
try to sort of use the ideas we have from
our everyday experience and apply them to particles, apply them
(04:02):
to these tiny little bits so that we can make
sense of them, because you know, you can't see these
things directly, so you have to sort of build a
mental picture, and we try to talk about how they
have mass and charge, and we even give them you know,
labor and spin and other sorts of things that were
familiar with from our world. But you have to wonder, like,
how well does that really work? Is it really relevant
(04:24):
or is the quantum realm just totally alien and we
will never really get our minds around it. Yeah, I
thought we had already decided that everything looks like Lego
pieces down at the fundamental level. They don't look like
little blocks with circles that say Lego on them. Well,
it's easy to do a test. You know, if you
step on them and they cause you great pain, then
they definitely are the shape of Lego pieces. I think
(04:47):
they make round legos too. Now finally to save parents,
But you know, this is all we can do as
humans is we can take the ideas we are familiar
with and we can try to map them down to
the quantum realm to think about this. Yeah, and sometimes
that intuition kind of fails, right, or it breaks down
when you get down to that quantum realm, that quantum level, right,
our ideas of what something is, or how solid something is,
(05:12):
or what shape it has, and it all sort of
breaks down into kind of mathematical goop right down at
the quantum. I think it has a little bit more
substance than mathematical GOOPI gloop, but really it's a bit
more No, it's a bit more poetic than mathematical sometimes
(05:32):
because well, we try to draw connections, like we talk
about quantum spin, and we fully admit that these particles
are not actually spinning, but they're doing something that is
very much like spin. It has a lot of similar characteristics,
and so we draw this analogy. And I think this
is one of the most beautiful things about physics, is
trying to describe the unknown in terms of the known.
(05:53):
You know, that's what languages, that's what art is, that's
what that's what it means to explore the universe is
to express it in a way that we can understand it,
and so that's all we can do. Yeah, are you
saying you don't understand google Goog? I'm saying googly groop
suggests some lack of understanding or nonsense, whereas in its
place there are some elegant intellectual structures to guide your mind.
(06:17):
I see, you know, potato, potato again, theoretical structures, googly goog,
it's all, it's all, you know, different names. But so
to the other podcast, we thought we would take a
trip down to that quantum level and kind of think
about a particular, you know, object that I think we're
all familiar with, and to sort of challenge our understanding
(06:38):
of what it looks like and what shape it has
and most importantly, what size it has down at the
quantum realm. And this is something that I have struggled
with as a particle physicist, just trying to visualize, just
trying to conceptualize it. How do I put this in
my mind? How do I think about this so I
can get some intuition right? And so today we'll be
tackling the question how big is an electron? Or how
(07:08):
small is an electron? Oh? Man, is this another potato
po typle thing. It's big and small depending on which
country here. The representatives of the Electron Union prefer to
be called big rather than small. Oh, I see, But
what does the electron itself prefer? Does it see itself
as a as a big or a little? Interview with
an Electron speculative fiction novel by J H winner of
(07:32):
the Nobel Price in literature and physics at the same time.
But yeah, you know, electrons are everywhere. They're one of
the three fundamental particles that make up everything that we are,
that you are, That planets and stars and galaxies and
dust are made out of um. And so it's an
important particle. And it makes yourself phone work, which without
which you would probably not be listening to this podcast. Yeah,
(07:55):
and it sort of sits at the frontier of particle physics.
Our goal is to explain everything in the universe in
terms of the smallest bits and pieces, the tiniest, roundest
lego pieces anywhere, And as far as we know, these
are the smallest bits. And so we wonder, like, is
it made of something smaller? How small is this thing? Anyway? Yeah,
(08:15):
what's the size of an electron? I guess that's a
question we haven't really talked about before. We just sort
of talked about electron and what they can do and
what they do, and we know they're small. But I
guess the question here is how small it is? Or
how big is it? Not? How big isn't it? Yeah,
And like with many of these mappings to the quantum realm,
I'm pretty sure you're going to be dissatisfied with the
answer because did you misname something again? Is it not
(08:40):
really called? Is it like an electron? Not really an electron? Well,
I don't want to give away the end there, you'll
have to stick around for another half hour. Well, this
is a question that, as always, we were wondering how
many people out there had thought about or wondered about
and what they knew about the answer to this question. So,
as usual, Daniel went out there into the wilderness of
the streets of Irvine, California and ask people how big
(09:03):
they thought an electron is. I like the way you
make it sound dangerous, like I'm hacking my way through
the jungle. I think talking to perfect strangers, it sounds
terrified to me. Well, here's what people had to say.
But before you hear these answers, think to yourself, what
would you guess is the size of an electron? Very small?
I know, like a couple of billion Adams can fit
(09:25):
on a period in in a book, So an electron
is Chillian quadrillion. I don't know. Sudden thinkers like small,
like smaller than that. Best guys like like a hundred
of a nanometer ten to the minus sixteen. Well, I
guess it's when it's a way function falls off? Is
(09:46):
one over eight or something like that? Is that how
we want to call it? What's thirteen point six e
v s and nanometers that it does red stuff? So
a couple d nanometers? Let's doing that? Also, no idea,
best es not that big tend to the negative on
all eleven or twelve or something like that. Like all right,
(10:09):
some pretty I feel like, pretty educated answers, Like some
people were talking about electron volts even I like the
guy who says smaller than a centimeter, like yeah, that's
that's true, yes and also correct, Yes, it's definitely correct. Um. No,
we shouldn't make fun of these people. They are giving
us their time, their and their energy, and so it's
(10:30):
fun just to just to know what people have in
their minds. And I think one of the common answers
is like, tend to the mind is a pretty big number.
But yeah, know I thought they were pretty I guess
you're at a at a university, so maybe a lot
of these folks just think in physics or something. But um,
you know, if you ask me, I don't know if
I would guess with exact figures or units. Well it's
(10:50):
interesting because if you ask me, I don't know what
I would say. It's a tricky question. Even what is
the meaning of the question, Like what does it mean
for the electron to have a side? Is? So it's complicated.
So someone interviewed on you on the street and ask
you this question, you'd be like, let's sit down for
a couple of hours, let me pull out my white board,
(11:11):
thank you for asking that question. And you see the
panic in their eyes. I've been waiting all my life
for perfect strangers. They would feign a phone call and
run away quickly. All right, Well, let's get into the
trying to answer this question. And I guess the first
thing is is that you're telling me is that this
is even Um, it's kind of almost a philosophical question.
It's like a tricky question in itself to ask what
(11:32):
is the size of an electron? Yeah, And you have
to be really careful about what you're doing. When you're
asking a question that you're used to asking about macroscopic
stuff and then applying that to microscopic stuff, you have
to be really careful about what you mean and what
exactly it is you're trying to learn. You know, like
when we think about a ball moving through space, we
can talk about its velocity. Cool, But when you want
(11:55):
to talk about the velocity of an electron, it's more
complicated because it doesn't have like the same kind of
half and so it's philosophy changes, and sometimes you can
know it, sometimes it's unknown, and so you know, there's
an analogy you can make there, but you have to
be careful about exactly what you're asking. And the same
is true when you ask about the size of something
super duper tiny, right, and and especially when you ask
(12:17):
about the size of a single thing, right, Like what
is it? What does it even mean to ask about
the size of anything? Is it like how much space
you occupy? Is it like the my longest dimension? Is
it the distance between you know, one and one side
of me to the other side of me. I think
that's it. I think it's the distance between your edges.
(12:37):
And so you have a size if you have edges
that don't touch, right, if you have if there's a
meaning to like there being a left of view and
a right of view, and your size is the distance
between them. You know, we have a meter stick, how
big is it? Well, the left side is one meter
from the right side. So that's sort of makes sense, right,
And this this all sounds, you know, obvious, but it's
(12:57):
going to be important when we get to the quantum
realm to be thinking about it in the same same
sort of set of ideas. Right, Yeah, I guess you've
got to think about what makes it a thing and
when is it stopped being a thing? And then then
you calculate kind of the distance between the edges of
what is and what is not a thing. Yeah, And
so you answer the question like what a size mean, Well,
(13:18):
it's the distance between the edges and that immediately, but
you can see you to the other question, what is
the edge, Like what is the edge of a meter
stick or the edge of a banana? How do you
define where that stops? And that's not so easy. Oh man,
you just make me imagine it endless banana and I
salivated a little bit. That's a whole universe to you,
right there. Man, maybe the whole universe is just one banana.
(13:40):
We are all just banana nos in a banana. We
should start that in the restaurant. You know, Olive Garden
has the endless bowl of salad, endless bread stick. We
can we can start selling the endless banana. But anyways,
so where is the edge of the banana? Right? You
would think, oh, I'm looking at it, I can tell
where it stops. And you either you poke it or
you're just looking at it. It sort of gives you
(14:00):
a sense for like where the edges. It doesn't have
a fuzzy edge, like it stops the all the atoms
that make up the banana are kind of stuck together,
and at some point there aren't any more of the
atoms that make up the banana. Yeah, although, if you're
zooming close enough right, everything that's not an absolute zero
is has a bit of a fuzzy edge, you know,
it's like boiling off atoms. Like the reason you can
(14:21):
smell banana is that there are volatile molecules on it
that are always leaving and so zooming close enough, and
there's there's a bit of a fuzzy edge there. But
still you can like take a stick and you can
poke the banana with your tiny stick and you can ask, like,
when does the banana give me resistance? Or is the
edge of it is sort of like, you know, where
is it push back? Okay, so that that would be
(14:42):
the edge of like an object microscopic option you're saying.
It has to do with when it no longer interacts
with you in the same way as the rest of
the banana. Yeah, And there's an important idea there, I think,
which is it's not where the stuff of the banana ends,
it's where the bananas forces push back. Because you know,
the banana itself is mostly made of these we'll talk
(15:03):
about in a minute, but time much smaller particles, and
the stuff of the banana, the thing that gives it
its volume is the forces. Right, If there were no
forces between these particles, they will collapse to a much
smaller pile. Like you just made a pile of all
the atoms inside the banana, it would be almost invisible.
Most of that volume comes from them spacing each other.
(15:23):
Out by the forces. So it's really the forces, the
pushing back that gives the banana it's volume and therefore
its size. I see, you wouldn't measure it as between
the center of the rightmost atom of the banana to
the center of the leftmost atom of the banana. You
would be you would extend that a little bit to
include like when that atom starts pushing back another adom
(15:45):
that tries to poke through the banana. Precisely because if
you bring your stick nearby, then the farthest, the most
extreme atom and your stick is not going to touch
the nucleus of that atom in your banana. They're going
to push against each other before they touch. And so
that's what I think of sort of the edge of
the banana is that force field that sort of protects
it from you know, external forces. Okay, so you're saying,
(16:07):
as a physicist, you would define the size of something
as as the edges of it, and the edges you
would define is when they start pushing other things from
going through it. Yeah, So really it's more about interactions
than it is about matter itself and particle physics, we
think a lot about particles and forces, matter and interactions.
(16:28):
And I think the size of something really depends more
on its interactions then on the stuff that's inside of it.
And that makes sense because if you want to know
the size of something, you want to know it for
a reason usually right, like you want to see if
the banana fits inside of a special you know, banana
carrying case that you aren't designing. You need to know,
you know, not when the set where the centers of
(16:49):
the atoms are, but you want to know, you know,
if you can fit the banana inside the case. That's
exactly it. But it already raises some problems, like what
if you had a blob of dark batter the shape
of a banana, how big is it? Well, if you
can't really interact with it, if you could like put
your finger through it, then you know, does that mean
(17:10):
that it's a banana shaped and blob of dark batter
is smaller? It doesn't have a size maybe even boy. Yeah,
so it gets it gets tricky pretty quickly. This thing,
which which we thought was simple is actually turns out
to be kind of subtle. Yeah, it's feel back the
answer to this question and also get into how big
an atom is, and then we'll get into how big
an electron it is. But first let's take a quick break,
(17:45):
all right, Daniel. So it seems like the question of
how big something is is kind of fuzzy in itself,
and so maybe a good way to kind of tackle
it is to start with the next level down from
a banana, which is like how big is a is
one of the atoms in the in the banana. So
remember that we decided that if we're going to talk
about the size of the atom, we're not going to
(18:07):
ask where is the stuff inside of it? We're gonna
ask where does it push back when it's poked? And
to figure that out, it's helpful to sort of imagine
a whole pile of atoms packed together. Here you have
you like imagine the banana is sort of like a crystal.
You know, it's like closely packed atoms of the banana.
And here it's determined again by the interaction between them,
Like how closely packed are they depends on how much
(18:30):
they resist being squeezed together. And in this case, for
an atom, it's you know, for banana. For other stuff,
it's a it's pretty small. It's like you know, fifty
to a couple hundred trillions of a meter. Is what
how you you would define how big anatom is. Yeah,
that's like this the separation between the center of one
(18:51):
atom and the center of another atom. Depending on the material,
and different things can sort of pack more tightly together
than other things. Like hydrogen, you can squeeze it down
to like thirty trillions of an atom between protons. But
if you're packing lead together, for example, it's almost two
d trillions of a meter between sort of the centers
(19:12):
of the nuclei. I say, it's it's like if you're
trying to measure the size of a bunch of marbles.
You would stick him in a container and see how
many you can sort of cramp together, and that kind
of tells you the size of each marble. Yeah, the
distance between the centers of the marbles. There you pack
them as closely as you can, and then you measure
the distance between the centers of the marbles. Is that
actually sort of because you know, when I think of
(19:33):
an atom, I think of like, um, you know, like
the popular culture drawing of an atom, which is like,
you know, little balls in the center and then electrons
flying around in orbit. You know, you know, and I
know that you know, they're actually like electron clouds. But
even the clouds have sort of a size, right, they're
drawn as little balloons that stick out of this center.
(19:55):
Is the size is the packing size that you're talking about,
like how many you can crime in banana, the same
as the size of those like electron clouds. Yeah, it's
very closely connected. And for a reason, those electrons are
the reason that the atoms don't pack more closely together,
Like you bring two hydrogen atoms near each other. It's
the electron clouds that determine how closely they get together
(20:18):
because they form like a covalent bond and make an
H two or something like that. And so it's those
electrons that determine the interactions between the atoms and determine
their spacing. And it's when those two things start overlapping,
is when they can no longer really get closer together. So, yeah,
the size of the electron cloud is very closely connected
to the size of the atom. It really is what
(20:39):
defines it. They're always interacting, right, no matter how far
apart there are, Like if I had a hydrogen atom
here and you had a hydrogen atom and Jupiter. Technically
they're sort of repelling each other, right or and or
attracting each other or not. They definitely do feel each other.
You're write the the extent of the electromagnetic force is infinite,
So there are electrons in Alpha Centaur that are pulling
(21:01):
on you or pushing on you, or depending on whatever
they're doing, technically touching you. Right, you're being touched by
an alpha centaur right now. I just got chills down
my spine a little bit to the left. Please, yes,
thank you. Crash that is that I've had. Yeah, well
it's a tricky concept. You're right. If we're going to
(21:21):
define size by sort of how you were responding when
you get poked, then you're right. You're being constantly poked
by everything in the universe. Well, even the stuff like
a build B zillion nine years away. Yeah, it is everything.
Everything in the universe is feeling you. Although you know
there's a time delay there, so the stuff in Alpha
Centauri is only feeling. Stuff is feeling where we were
(21:43):
a long time ago as a separate issue. So my
size depends on time as well. Jeez. But you know,
those those things are pretty negligible, and so you can
think about like when these things really have an effect
if you probe if you shot an electron at um
hi'd gin atom, when would it deflect the electron? And
if you shot you know, a meter to the right,
(22:04):
it wouldn't change the path of the electron really at all.
It would, but just it would be very little, It
would be very little bit negligible. But then when you
you know, hit it right on, then it's going to
bounce right back. And and so you can use that
to sort of get a sense for what is the
meaningful sort of charge radius of a particle. And you're right,
it's there's no crisp edge there. So there's a small
(22:26):
complication there also because it turns out that the size
of something depends on not just what you poke it with,
but how hard you poke it. Like, if you poke
an atom very gently, it'll seem bigger because you'll notice
smaller deflections further away. If you poke it very hard,
it will actually seem smaller because you'll overpower the electrons
(22:48):
and the outside and only see the nucleus on the inside.
There's no point at which it goes to zero though,
you're right, right, yeah, So it's it's kind of fuzzy
and maybe kind of arbitrary, but you're saying, it's like
when when you would actually fee you the force of
that electron, that's when maybe you would say, all right,
it's sort of impinging on it, which means it's sort
of bumping up against it. Mm hmm, And it's not
totally arbitrary. Like when you squeeze atoms together, they settle
(23:11):
in at a certain distance from each other, so that
totally tells you what the equilibrium location is for for
the distance between atoms, and that I think is a
reasonable way to define the size. But you know, you're right,
you have to think about, like what am my meaning
by size in this context? In this other context? This
basic thing we think about like should be obvious to
talk about is it turns out to have a lot
(23:32):
of wrinkles to it, all right, So that's kind of
how you would define an atom is when it starts
to push back another atom, and how much when you
crow them inside of a box, you know, what's the
natural spacing that they have between them? And it's you're
saying sort of related to those electron clouds, which is
how kind of how far away the electron goes from
the nuclei right, Okay, so that's a that's an atom um.
(23:56):
But I guess it gets strict when you talk about
individual particles. So let's go down one more level to
the proton inside of the nucleus. How big? How how
big would you say a proton is? This is a
wonderful question. And you know, if you're breaking open the atom,
if you're shooting electrons at the atom, it's going to
get repelled by the electrons on the outside of it.
But if you give them enough energy, then they can
(24:17):
sort of penetrate through there, and then you can start
to probe the proton inside there, and you can ask, like,
how big is this thing? And so we do that exactly.
We shoot electrons at protons or hydrogen atoms or or
it doesn't really matter if the electron is there anymore,
because the probe we're shooting with has so much energy,
and we see where does it bounce back and where
(24:37):
does it sort of stop bouncing back, and that gives
us a sense for how big the proton is, and
so we actually have a number for that. But it's
tricky because the proton is also made out of things
inside of it, sort of like the atom itself. It is.
Protons are made of smaller bits that are slashing around
inside of it. Those are the corks. But remember that
we're trying to define the size of an object, the
(24:59):
proton this case, not by where the stuff is inside it,
but where it pushes back. And the corks hang out
together and push back against the other protons. So if
we use our definition, it's the distance between the protons
that's going to determine the size of the protons. And
that's connected, of course to how the corks are arranged,
(25:19):
how they're happy to be inside the proton. The proton
is sort of like a cork atom. I See if
they were comfortable being a mile apart, you know, like
if you try to split it more than a mile
or squish the more of them out, they would prefer
to be a mile up apart from each other. Now,
you would say the size of those two electron at
courts is about a mile. So the size of the
proton that's that's made up of those corks, yeah, it
(25:40):
would be about a mile. But you know, we have
nuclei and they have got protons and neutrons inside of them,
and each one is like its own little particle. They
get squeezed together, but they hang out. They keep their
own little particle nature, and so it's just like packing
marbles together. You can ask about like the distance between
the center of one proton and another, or a proton
and a neutron. That's what we think of as the
(26:01):
size of the proton. How much can you pack in
the quarts that are inside of the proton? Yeah, and
that's a really crazy number. That's like one quadrillionth of
a meter. It's a really small number. Uh. And that's
smaller than a nanometer for sure. It's smaller than a
centimeter as well. It's smaller than a mile apparently as well. Um,
(26:24):
so that's pretty small. That's pretty small. Yeah, Like, how
how big is that in relation to like the size
of an atom. Well, an atom is you know, like
ten to a hundred ish um trillionth of a meter,
So this is one quadrillionth of a meter, So it's
like one ten thousands or one hundred thousands the size
of an atom. So it's very small compared to the atom.
(26:47):
Bare to the electron radius, the proton is super tiny. Okay,
wait wait, so um, we have an atom and how
about the just the nucleus of the atom. How close
together are those protons and neutrons in the nucleus packed together?
Those are very tightly packed together. And and again remember
that's because that's sort of how the size of the
proton is determined. It's like how do those things cluster together?
(27:08):
And so the size of like if you have the
nucleus of an atom with you know, a hundred protons
and neutrons in it, it's not that much bigger than
one protonomy. It's like packing above those marbles together. So
it's going to be ordered magnitude quadrilliants of a meter.
Oh wow, so the new And that's why they say,
like the anatom is mostly empty space because you know
(27:29):
what you would say is the size of it. Actually
the nucleus is like this tiny little bit of it inside. Yeah.
And the way that they probe this is two different ways.
One is they shoot an electron at proton. But sometimes
also they just look at an atom. They just watch
an atom sitting there. It's got a proton and an
electron and the electron is whizzing all around. And sometimes
(27:52):
this is super weird. Sometimes the electron goes inside the proton,
like in a quantum mechanical way, or like it actually
goes through what's the difference quantum mechanics is reality, dude, um,
Like if you were to you know, I mean, like
if you were to open the true Dinger's box and
you would you would suddenly find it inside of the news. Yeah,
(28:13):
the electron in one of its states has non zero
probability density to be inside the proton. And when this happens,
it's sort of like partially cancels some of the charge
pull of this thing because you have the electron now
inside the positive atom and then it escapes. But depending
on the size of the proton it escaped, this happens
(28:34):
more or less often, so you can measure like how
often the electron is inside the proton, and that tells
you how big the proton is, because the bigger the
proton is, the more often this happens. So this is
another way we sort of get a sense for how
big is the proton. I see, using like probability, like
you throw a bunch of darts at it, only sometimes
(28:56):
you hit hit the proton. Then that sort of tells
you the size. Yeah, exactly, And that's actually the most
sensitive test. Basically using the hydrogen's own electron, like pass
it through the proton and give you a sense for
how big it is. It's crazy. Well, all right, so
a proton is about you're seeing one ten thousands of
the size of a typical atom. That's pretty small, because
(29:16):
a pretty small. So alright, so let's get there. Let's
get down now to the last level, which is how
big is an electron? And I imagine that's going to
be even smaller, but we'll get into that, but first
let's take a quick break, all right, Daniel. So now
(29:45):
we're down to one of the fundamental particles, the electron,
and we're asking the question how big is it? Or
how small isn't it? Or how big isn't it? Amount
of negatives here, um and so, And I guess what
we're talking going to talk about. It sort of applies
to quarts as well, right, because we're now talking about
(30:06):
single particles, not like clusters of particles. Yeah, and remember
that our theory is very hierarchical. We start with matter,
and then we go to molecules, from molecules to atoms,
from atoms to protons and electrons, and then to quarks
and electrons, and we're sort of have shells inside shells
inside shells, and so this is sort of our current
level of knowledge, and we can ask like, are these
(30:27):
particles that we see, um, are they the smallest possible thing?
Or is it possible there's something else inside them? So
you're right there, quarks and electrons are sort of as
far as we've gone, and so in some sense, asking
how big are they is asking are they the end?
Are they the tiniest, smallest possible thing? Or they possibly
made of something smaller? Oh? I see, because if you
(30:48):
can split them, that means there's something smaller inside. I
guess that's pretty obvious. And that's for you. That sounds
deep and it is deep, but it's also kind of obvious,
like if you can break it into smaller pieces, then
it's there were made of something else. As far as
we know, quarks and electrons are not yet made of
something smaller. But that doesn't tell you necessarily how big
they are. Right, they could be the smallest possible thing
(31:10):
and still have a finite size. Right they could be um,
the legos of the universe. Lego. Yeah, it could be
the smallest lego you can have, but um, that can
be smaller, smaller, big, that could be smaller big, And
that's fascinating when you learn a number about the universe. Like,
let's say we somehow proved that quirks and electrons are
not made of anything smaller. They have the smallest lego blocks,
(31:31):
and we measured their size, Then we'd we'd know something
really deep and basic about the universe, like it's made
of legos this size, and you have to wonder, like, well,
why that size and not something else? What does that
tell you about the universe to know that fundamental fact? Yeah?
Did you know there are legos that are smaller than
the single unit lego? What? Like you you would think
(31:52):
the smallest lego is just like one square with one
circle on it, right by saying people have smashed the
legos together and make some legos covered the constituent pieces
and legos. No, yeah, they make uh this is kind
of weird but uh probably not consequential. But um, they
make smaller pieces. It makes pieces that fit inside of
(32:12):
the whole that some of the single circle lego pieces
have inside. Oh my god, you have just violated the
standard model of legos. Noble price. Please you've got the
prize from that one. Anyways, Um, so, yeah, so let's
talk about how big an electron Isn't let's use that
as our single particle example. And does it even make
(32:34):
sense to talk about the size of a single particle, Daniel,
It's hard to talk about the size of a single
particle if you haven't measured the stuff inside of it.
Because we've talked about the size of atoms and protons
based on like how happy this stuff inside of it
is to be next near each other, like how closely
does it pack? So for a fundamental particle you have
to go back to like the poking it and be like, well,
(32:57):
if I poked an electron with a stick, where were
pushed back? But that's sort of unsatisfying to me. Couldn't
can't I just you know, pack a bunch of electrons
in a in a glass jar and see, wouldn't that
tell me sort of the size of it, Like how
comfortable an electron is to another electron or to a proton.
Wouldn't that sort of tell you this sort of the size,
(33:17):
just like we did with the marbles and the atoms. Yeah,
that sounds like a really fun experiment. I want to
take like a gas of pure electrons and squeeze it
down together and see what happens. The problem is that
there's not like a clear answer, like the heart do
you squeeze the closer they get together, it's not like
an equilibrium like with protons or with atoms, because these
are all just negatively charged particles. There's no chill state
(33:39):
where they're like, hey, you're there, I'm here. All is good,
and so instead you want to like take them and
like poke them, like, well, if you poke them with
an electron, then they bounce back for sure, But what
if you poke them with neutrinos then they don't bounce
back at all, Or what if you poke them with
dark matter? Then they don't bounce back, And so you're
back to this like fuzziness of like you know, if
(34:01):
it depends on how it's pushing back, then it depends
on what you're poking it with. And then size isn't
something that's like inherent to the object. It's about the interaction,
which means it depends also on the thing you're interacting
it with, which is so frustrating. Oh, I see what
you're saying. Like if I had a cloud of electrons,
you could maybe talk about where the cloud is, and
(34:21):
where the cloud isn't, where the electors are and where
there aren't. But with one single electron, it's hard to
say where it ends. It's hard to say where it ends,
like is there a left side to the electron and
the right side to the electron? Are those things even
the same thing? Because it depends on what you you're
trying to touch it with, right, Like, if you're trying
to touch it with another electron, it would maybe repel
(34:41):
at a certain distance, But if you try to poke
it with a proton, then it would maybe attract at
a different distance. Yeah, well not so much electron versus proton,
because they both feel the electromagnetism. But what if you
used a different force, if you use like the weak
nuclear force, or if you used you know, gravity, or
if you used electromagnetism, is them than the size that
you would get from electron is different. And we're turning
(35:05):
to a neutrino. An electron has those eyes. It doesn't like,
I don't care, Like the neutrino doesn't care. A neutrino
would pass through a cloud of electrons and have a
much lower chance of interacting than another electron would, like
it wouldn't even know it's there, yeah, or dark matter, right,
pokeing a pile of electrons with a stick of dark matter,
you're gonna get almost no interactions, or maybe no interactions.
(35:28):
We don't even know about dark matter. And this is
the problem. It makes sense to define size in terms
of interactions, like where is something pushed back, But it
also is troublesome because then it depends on what you're
pushing on it with. So that's kind of a problem
in defining the size of an electron because it depends
on what you poke it with. So then we try
something else. We say, well, let's think about it like
quantum mechanically, Like we've talked about where the electron is,
(35:52):
and it's defined by like it's quantum mechanical wave function,
and you know you were talking about like those balloon
shapes where the electron is. You know, it's the sort
of the most you can localize an electron, Like what's
the size of that quantum packet? You want to think
about it like as a tiny quantum object. That's like
another way to try to grapple with it because their
probability curves right, Like you know where the cloud is
(36:12):
fuzzy tells you that the probability that the electron is
there is small, but where the cloud is kind of thick,
it tells you that there's a high probability that the
electron is there. But that doesn't really give you any
insight because that size can be almost anything. It depends
on the uncertainty principle. If you know almost nothing about
the velocity of the momentum of the electron, then you
(36:34):
can know exactly where it is, which means it has
like zero that quantum mechanical packets zero with And on
the flip side, if you know everything about its velocity,
then it's packet is infinitely wide, like exists everywhere in
the universe simultaneously have like a universe sized electron. So
that's intellectually not that satisfying either. But what if you
(36:57):
assume an electron is just standing still, like when you're
to measure your kid how all they are and it's
impossible because they keep moving. But what if you can
get it to stand still? Oh wouldn't what would that happen?
Would you be able to then get a pretty accurate size.
If you're measuring the velocity of the particle, you're getting
it to stand still has no velocity, and you say
it has zero velocity, then it has infinite size because
(37:19):
you can't know the product. Remember the product of the
position and momentum uncertainty has to equal a certain number.
And so if you're narrowing down the speed of the
electron really really well, that means you don't know anything
about where it is. It's an infinite plane. Wave size
is only distance, whereas you know in particle physics, distance
(37:40):
is kind of intertwined with time as well in velocity.
But then on the flip side, if you say I
don't care at all about how fast it is, I
just want to know where it is, then you can
localize it as much as you want. You can make
it infinitely narrow. And so that also doesn't give you
any sense of like the size of the electron. So
strike to we can can use poking or are quantum mathematics.
(38:01):
So does that mean that the electron has no size,
that it's impossible to define the size of an electron.
It kind of does currently. I mean in our theory,
the way we actually use it is we assume the
electron has no size at all, It has zero volume.
That it's just like a point in space. The left
is the right, the top is the bottom, the back
(38:22):
is the front. There's no extent to it at all.
It's sort of mathematically and and because of all the
things we just talked about, I guess that that's true. Yeah,
you can't measure the size of an electron. It doesn't
make any sense to think about it. Yeah, in our theories,
we just put zero because we assume that there's nothing there.
We have no way to really see the size of
the electron. But you know, we do continue to try.
(38:43):
We do smash particles at the electron, hoping that we'll
see a break open, hoping that we'll see other little
particles come out of it. But I guess getting back
to the size of the electron itself, um, I mean,
it's not like it has no size because it's it's
not a mile wide, Like, would you even say that
the electron is all electrons are a mile mile wide?
(39:05):
I don't know what to say for the size of
the electron, you know, And that's why I predicted, I
think correctly, that you'd be unsatisfied with Oh my god,
it's not really you can't tell the future, can Yeah, well,
I can in this case, like I think the way
I think about it currently is as a point, But
I also know that that makes no sense because like,
(39:27):
how do you have something that has mass but has
no volume because then has infinite density, which is nonsense,
right is it? Electrons have mass, they have mass, and
they have charge, Like where does that charge go? Where
is it in the electron if it has no volume.
We're just used to thinking about stuff as having sizes
having volume, So to imagine that the basic building box
(39:48):
of the universe themselves are of zero volume is really weird.
But I guess maybe you know that that's the theory
of it. But practically speaking, I mean, we can talk
about what's what's practical to you and me is like
electromagnetic forces, right, you know, And it doesn't make sense
in terms of neutrinos are dark matter, but kind of
what's practical electromagnetic forces? And so couldn't we sort of
(40:10):
maybe give a practical size to the electron because of that,
like like what's the closest to electrons in one atom?
How close can they get to electrons in another atom?
Wouldn't that give you a general size? Yeah, and we've
done that we like pounded electrons near each other and
try to get them as close together as possible, And
so far we haven't found a limit, Like, there's no
(40:33):
point at which the electrons will not get closer to
each other. And so far we've gotten down about ten
to the minus twenty meters. And you do that by
shooting really high energy electrons at other electrons and try
to get them really close together. So that's as far
as we could tell. We can't tell the difference between
the electrons have no volume, and they have some volume
(40:55):
that's smaller than ten to the minus twenty. We can't
tell the difference. So far. They look like their point like,
but we have some sort of limited resolution there in
our ability to probe. So what happens if I the
whole universe was just like a proton and an electron,
I guess the electron would orbit the proton. That's what
hydrogen is. Yeah, The size the hydrogen comes from their interactions. Right,
(41:15):
Most of the volume of all the stuff in the
universe comes from the interactions, not from any actual volume
of the particles that make them up. All right, Well,
you're right, this is very unsatisfying. Anim Well, that's satisfying
to me that at least I was right about that.
But it's a it's a really fun puzzle because I
think it's interesting to try to grapple with the quantum
(41:36):
realm and try to understand what are the limits of
our ability to map these concepts size and mass and
charge and velocity down to these tiny particles that, in
the end are the reality, are the truth about our universe. Yeah,
And I think it's interesting how, you know, you sort
of put it that it's all about the interactions, you know,
And it's hard to think about an electron not having
(41:57):
like a surface or you know, an st where it's
no longer an electron, And it all sort of depends
on what you're trying to look at it with, you know,
Like if you're trying to look at it with neutrinos,
then you wouldn't see anything at all. Yeah, But if
you looked at it with the electrons, it would feel
like a certain size maybe. Yeah. And this is connected
to some of the other puzzles we talked about, like
(42:17):
does the electron actually spin? We know that it's either
a point, in which case it doesn't make sense for
it to spin like a point literally cannot spin, or
that it's super tiny. But if it's super tiny and
it has a surface, then it's spinning so fast that
that surface is moving faster than the speed of light.
So at some point, like it doesn't even make sense
(42:38):
for it to have a non zero size. At some point,
nothing makes sense, Daniel, life is meaningless, And that's usually
about forty five minutes into every episode. The incredible thing
is that we can understand it at all, That we
can take these ideas from our everyday experience of like
eating bananas and throwing balls around, and then it can
(42:59):
give us any side into the microscopic. You know that,
because the microscopic is so weird, so alien, it's incredible
it works at all that I even have a job.
But yeah, but that's the thing it was. We don't
understand it, but yet at the same time we're able to,
you know, predict it and describe it with math. But
that doesn't mean we understand it, right, That's what understanding is.
(43:19):
As far as I know, I don't know any deeper
level of understanding. When you pass it off to the
philosophers and you can ask them, like, you know, what
does it mean? Man? But in the end. What we're
trying to do is physicists is just sort of describe
accurately the world we see around us, build a model
in our heads that makes sense, describe all this unknown
in terms of the known. That's that's all the understanding
(43:40):
we can hope for. Well, I guess what I mean
is like at some point we thought the proton was
a proton, and we had to math to describe it,
and we thought we understood it. But then then it
turned out we that we there was more to the
proton than we thought, and we didn't actually understand the proton.
It was made out of quirks, for example. So I
feel like, you know, you have a mathematical di ccription
of stuff, but you don't know if you're really understanding
(44:03):
it to the fundamental level. And all of these mathematical
descriptions they work up to a point. Like your idea
thinking about a proton as a fundamental particle as a
point particle that mostly works. It works unless you get
up to really high energies, energies where you can see
inside the proton, because the energies are greater than the
bonds that are holding the proton together. And so as
(44:24):
we keep pushing to higher and higher energies. We're looking
deeper and deeper into the real truth the smallest scales
of the universe. And that's what limits how small we
can see is the energy with which we probe it.
And that's why, like building a bigger super collider would
let us maybe see whether the electron had bits inside
of it. Yeah, keep funding physics is hey, I'm on message.
(44:46):
If nothing else, keep sending those checks. Please, if you
have to pick between donating to bananas or fundamental physics,
you know where I stand on that. Bananas, right, because
bananas are made out of fundamental partners. All right, Well,
we hope you enjoyed that, And maybe the next time
you take a bite out of a banana or your
(45:07):
fruit of choice, maybe think about what it actually means
to take a bite. I feel like we've thrown everything
into question now, Daniel, Like, what does it even mean
to take a bite into When my teeth end and
when does the banana begin? I don't know, but every
banana you've ever eaten is made out of zero volume particles.
Chew on that and think about it until next week.
Thanks for joining us, See you next time. Before you
(45:35):
still have a question after listening to all these explanations,
please drop us a line. We'd love to hear from you.
You can find us at Facebook, Twitter, and Instagram at
Daniel and Jorge That's one Word, or email us at
Feedback at Daniel and Jorge dot com. Thanks for listening,
and remember that Daniel and Jorge Explain the Universe is
a production of I Heart Radio. For more podcast from
(45:57):
My Heart Radio, visit the i heart Radio app, Apple Podcasts,
or wherever you listen to your favorite shows. Yeah m
Hosts And Creators
Daniel Whiteson
Kelly Weinersmith
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