Listener Questions Volume #2

Daniel and Kelly answer questions from curious listeners, about big black holes, nuking hurricanes and the philosophy of photons.

See omnystudio.com/listener for privacy information.

Episode Transcript

Speaker 1 (00:05):
So I absolutely love talking about the tiniest little particles,
the hearts of black holes, and how we could be
misunderstanding like all of it.

Speaker 2 (00:14):
And I love talking about parasites, teeny tiny little wasps
and dung beetles. But judging from my husband's face at
the dinner table, it's possible that not everyone shares exactly
my interests.

Speaker 3 (00:27):
So what do you want to hear about for the podcast?

Speaker 1 (00:30):
We usually pick topics that excite us and we think
you'll enjoy, but you know we both have our weird
quirks and preferences, so we want to hear from you.
We'd love to answer questions you have about the universe,
what you think is extraordinary and interesting and needs more explanation.
Sometimes we turn your idea into a whole episode. Sometimes
we give you a fifteen minute answer during a listener

(00:52):
question session.

Speaker 2 (00:53):
And the questions you send us will help us more
generally to gauge our audience's interests, which help us pick
additional topics for the future.

Speaker 1 (01:01):
So please don't be shy I send us your questions.
We want to hear from you. We want this podcast
to be about what you are curious about, and today
we're tackling three fantastic, hilarious, amazing questions send to us
by listeners just like you, And if you want.

Speaker 2 (01:16):
To be on the next show, you can email us
at Questions at Daniel and Kelly dot org.

Speaker 1 (01:20):
Your science podcast fame.

Speaker 2 (01:22):
Awaits Welcome to Daniel and Kelly's Extraordinary Universe.

Speaker 1 (01:42):
Hi. I'm Daniel, I'm a particle of physicist and I've
never run out of questions.

Speaker 3 (01:47):
Hi.

Speaker 2 (01:47):
I'm Kelly Wiener Smith And every question I ask pleads
to even more questions.

Speaker 1 (01:52):
Why is that? Do you think?

Speaker 2 (01:53):
Because we know so little about everything? I think at
the end of the day.

Speaker 1 (01:57):
See, we even have questions about questions, there's never an
end to them.

Speaker 2 (02:01):
So my question for you today, Daniel, is when you
were working on a PhD, did you get a satisfying
answer to your big question?

Speaker 1 (02:10):
You're really going to ask me that that's so embarrassing.
You know. I did a PhD which was pretty technical.
I was measuring how often two top quarks are made
and decay in a very specific way. And it was
only when I was writing up my thesis five years
into the project that I did enough reading of the
literature to understand, like, hey, is this interesting at all?

(02:32):
And how am I contributing to the scientific conversation? And
that's when I learned I basically wasn't. Oh no, So
what did.

Speaker 3 (02:40):
You publish it? Anyway? I guess at that point you
have to.

Speaker 1 (02:42):
Yeah, absolutely, you have to. And you know that's just
part of the process, because when you start graduate school,
you're like a science baby. I mean, you have your
inspiration for why you want to study particles, but you
don't know what the interesting questions are and what we
could actually learn in a reasonable amount of time. So
you rely on senior people the guide you and help
you pick a time topic and get started on it.
And so it was only when I finished my thesis

(03:04):
that I feel like I knew enough to know what
was interesting and what wasn't.

Speaker 3 (03:08):
Oh man, that's frustrating.

Speaker 2 (03:10):
I always tell the students that I work with, do
you feel like you've read enough?

Speaker 3 (03:13):
Yeah? You haven't?

Speaker 2 (03:14):
Keep reading, go back and read, and they're like, no, no,
I'm good. I'm like, oh, you're good, read twice as much.

Speaker 1 (03:19):
Are not good? Yet?

Speaker 2 (03:20):
You just need to keep reading. That solves a lot
of problems. But man, it's hard to know when to stop.

Speaker 1 (03:24):
And that's why your book has such a lengthy bibliography.

Speaker 3 (03:29):
At least I practice what I preach.

Speaker 1 (03:31):
Yes, And how about you? Do you feel like your
thesis was exciting, was compelling that you got to answer
a big, fat, juicy question.

Speaker 2 (03:38):
I was asking whether or not this brain infecting parasite
changes like some personality traits in the fish that it infects.
And after like seven years it took me a really
long time to get my PhD. The answer is like no.

Speaker 1 (03:55):
But you know, negative answers are just as important, right,
you can't not publish it because the answers not exciting
or not that interesting. It's important to cross things off
the list. You know. I've been doing particle physics for decades.
I've never discovered a new particle. Every single paper I've
written is like, and we didn't find this, and we
didn't find that, and we didn't find this other thing.

Speaker 2 (04:15):
I felt like I had designed a really good experiment,
and so when I decided the answer was no, I
was like, Oh, the ANSWER's really no.

Speaker 3 (04:21):
I feel good.

Speaker 2 (04:22):
About the answer being no, so yeah, no can be
a satisfying answer. Also, but my PhD advisor would like
me to finish publishing that paper.

Speaker 1 (04:28):
Wait, still are you joking, No, I mean it.

Speaker 3 (04:31):
Yeah.

Speaker 2 (04:32):
I've published a lot of side projects, and actually all
of those side projects ended up becoming my dissertation. So
we have had a lot of publications together, but the
main project ended up being so massive and overwhelming and
hard to analyze that I still haven't had a chance
to write it up. But that is my twenty twenty
five project, and that's why I wrote a bunch of
my other collaborators to say, I'm not doing anything else

(04:55):
this year.

Speaker 3 (04:56):
I'm finally going to publish my PhD.

Speaker 1 (04:58):
Was it also your twenty twenty project and your twenty
fifteen projects? Yeah? Science takes a while, people, Science takes
a while.

Speaker 2 (05:06):
It does, unfortunately, But you know what doesn't take a
while sending an email to.

Speaker 3 (05:11):
You and me.

Speaker 2 (05:12):
That's right, and our amazing listeners have done that. And
we have three fantastic questions today, all of them sort
of more Daniel centric, but we've got a lot of
Kelly centric questions queued up for our next Audience Questions episode.
But should we jump into our first audience question today?

Speaker 1 (05:30):
Absolutely, let's do it. And as a reminder, we're going
to be answering this question from a listener and then
reaching out to the listener to give us a grade
to see did we answer your question or did we
just confuse even more or leave you unsatisfied with Nobody
knows the answer, which is usually the way things turn out.

Speaker 3 (05:47):
But at least that's a real answer. So here we go.

Speaker 4 (05:50):
I have a question about the presence of super massive
black holes in our galaxy. So my understanding is, we
have evidence that a number of smaller galaxies have merged
with the Milky Way in the past, right, and pretty
much all galaxies have super massive black holes at their center, right,
So what happened with those other black holes when they

(06:12):
entered our galaxy? Unless it was a direct hit, they
wouldn't have merged with our black hole immediately, right? So
how long did this merger take? And in the interim
it seems like there could have been just several super
massive black holes flying through our galaxy circling the center.
Do we have evidence of that happening? It seems like
they must have left quite a path of destruction through

(06:34):
the Milky Way. If not, is it strange that we
can't find evidence of this? And could any still be
out there right now?

Speaker 3 (06:41):
Wow?

Speaker 2 (06:42):
This is a super interesting and super informed question. Where
do we start here, Daniel, Maybe we start with what
happens when galaxies merge, because this was all sort of
a new to me.

Speaker 1 (06:52):
Yeah, this is a really fascinating question, basically wondering like,
why don't we see a bunch of black holes zooming
around the center of the galaxy. Why does it seem
like there's only one in the center of the Milky Way.
Chris is a pretty sophisticated understanding of how galaxies merge,
and that's suggests to him like there should be a
bunch of black holes. And that's my favorite kind of
question when you hear a listener having internalized something about

(07:14):
physics and then drawing some conclusion, comparing that to the
understanding and being like, wait, some thing's not fitting here.
What am I missing? Because that's the essential process of science,
right build that model compared to the data, update it.
It's wonderful to see it happening in real time. So yeah,
I agree we should start by reminding the listeners, at
least who might not know as much as Chris does
about how galaxies come together.

Speaker 2 (07:35):
Based on what you just said, I just want to
confirm is it actually the case that every galaxy has
a black hole at the middle, because I hadn't realized that.
But we've seen a lot of galaxy, so we should
know if that's a consistent thing or not.

Speaker 1 (07:48):
So that's a great question. We don't have a definitive
answer because we can't look at every galaxy in the universe.
But every single galaxy we've looked at has a supermassive
black hole at the center, or we can explain where
it went, like it got kicked out, or there's a
collision or something. So there's very strong evidence that every
galaxy has a super massive black hole, but it's not

(08:08):
something we understand. If we try to model the formation
of those black holes are the centers of galaxies, The
models don't describe the data, like we can't get our
black holes to be as big in the models as
we see in reality, like they're huge black holes of
the center of galaxies only a billion years after the
universe forms. We have no idea how you make such
a big black hole so quickly. So there's a lot

(08:29):
we still don't understand about super massive black holes. For sure.

Speaker 2 (08:32):
Do we know why there's a super massive black hole
at the center of every galaxy does that make sense.

Speaker 1 (08:37):
We don't know why they're so big, but it makes
sense that. You know, galaxies are big pools of stuff,
and stuff pulls on itself and falls towards the center,
and eventually, if you get stuff dense enough, you're going
to get a black hole. So it makes sense to
have a black hole at the center of every galaxy.
It's the densest point, and you cross that threshold, you
get black holes.

Speaker 2 (08:54):
So yeah, okay, all right, So then let's back up
to what happens when galaxies.

Speaker 1 (08:58):
Merg Yeah, because Chris is asking why we don't see
multiple black holes at the center of the Milky Way
from multiple galaxies merging, and this touches on the whole
story of how galaxies form. We think that all the
galaxies we see today are made up of a bunch
of little baby galaxies that came together to make big galaxies.
So we don't think big galaxies were formed all at

(09:19):
once into some huge gravitational collapse in the early universe.
We think that a bunch of little galaxies were made
and then those galaxies come together to make bigger galaxies.
It's like a hierarchical bottom up formation rather than just
like a single formation of a big galaxy.

Speaker 2 (09:35):
Is it easy to explain why we think it started
with little galaxies coming together as opposed to just lots
of big galaxies forming.

Speaker 1 (09:41):
For a long time, there were both of those theories,
the sort of top down and the bottom up approach.
But you can tell the difference in the models, like
the age of the stars and the formation and the
structure of the galaxies are different if you start from
little ones which then build up together to make big ones.
And we can see evidence for this, for example, in
our Milky Way, and surrounding the Milky Way, we see

(10:02):
a bunch of little galaxies we call them dwarf galaxies
that are not fully incorporated, that are sort of in
the gravitational grasp of the Milky Way but not completely eaten.
So we see a lot of evidence for this theory
that galaxies are formed sort of bottom up.

Speaker 2 (10:15):
All right, So galaxies are formed bottom up. They all
have super massive black holes at the center. I think
we did talk in another episode about how sometimes galaxies merge,
and this is one way the Earth we could all
be in trouble if we got too close and we
merged with another system that's coming back to me now.

Speaker 1 (10:31):
And so these supermassive black holes at the center. Just
to remind folks, these are not little normal stellar black
holes like a black hole that you think about from
a collapsing star, Like a star burns up all of
its gas and then it can no longer resist gravity
and eventually collapses and forms a black hole. That's the
kind of thing we expect to be like ten solar
masses ten times the mass of our sun. Maybe a

(10:52):
super massive black hole is something that's like ten thousand,
or a million, or a billion times the mass of
our Sun. So like really extraordinarily massive objects that are
out there at the center of these galaxies. Even these
dwarf galaxies have them up to like fifty thousand times
the mass of our Sun.

Speaker 2 (11:10):
So if we know that dying suns cause black holes,
how do we get super massive black holes. Is it
like a dying sun party, like they all get together
to see the sunset or something.

Speaker 1 (11:23):
We don't know the answer to that. Like, if you
design a model, you say I'm going to use all
the known physics we have and the gravity, and you
create these galaxies, you get black holes at the center,
But they don't get this big, like, they don't get
as big as we see them out there in the universe.
So they get massive, and we even call them super massive,
but they don't get as big as we see so
we don't understand exactly how they form. There's lots of

(11:45):
crazy theories. One theory is that black holes may have
formed much much earlier, they called primordial black holes, before
even there was matter, when the universe was still cooling
and coalescing. Instead of making protons, maybe it made a
bunch of black holes. So the black holes are much
older than we think, and they've been forming matter for
a long time. Nobody's ever seen one of these primordial
black holes, you know. There's a lot of ideas for

(12:07):
how these black holes could have gotten so massive. But
for Chris's question, the point is all of these galaxies
come with a super massive black hole. So what happens
to the black hole during the merger right when two
galaxies come together make a bigger galaxy, to the black
holes always combine? How long does that take? Why don't
we see black holes in our milky way? This is
super fascinating because black holes are really awesome objects and

(12:29):
they're really massive, and the short version of the story
is that we think galaxies come together and then black
holes merge. We think that super massive black holes can
merge into bigger black holes just the same way like
two stars that are binary stars both collapse to black holes.
They can combine into a bigger black hole, and we've
seen evidence of the smaller black hole collapse in merger.

(12:51):
That's where the famous gravitational waves are from. They're from
two black holes orbiting each other, going faster and faster
and faster as they coalesce into a bigger black hole.
So we've seen gravitational waves from stellar mass black holes.
And then last year we saw a lot of evidence
a little bit less direct for gravitational radiation from super

(13:12):
massive black hole mergers, which we think correspond to galaxy mergers.
Super massive black holes at the hearts of galaxies coming together,
swirling around each other, generating gravitational radiation, and then mentionally
collapsing into a super duper massive black hole.

Speaker 2 (13:28):
Is this a possible explanation for why super massive black
holes are bigger than theory predicts or has this already
been explored?

Speaker 3 (13:37):
Like are they bigger?

Speaker 2 (13:38):
Because actually you're just looking at one and it was
three that came together, or that doesn't explain it.

Speaker 1 (13:43):
No, that doesn't explain it. We include that in our model,
and it can't describe the black holes that we see
out there, not something else, some other process that's juicing
them up. You know, there was this paper last year
about how black holes could be causing dark energy, and
this is correlation between the acceleration of the universe and
the side the super massive black holes. But people don't
really know if that's anything or nothing. There are papers

(14:05):
examining like the size of the bulge in the galaxy
and the size of the black hole. Those seem to
be correlated, which suggests that it's not just something local,
it's a bigger process across the galaxy. It's very active
area of research, and in a few years I think
we'll know a lot more because we're gathering a lot
more data about super massive black hole mergers from these
pulsar timing arrays. You use the whole galaxy basically as

(14:28):
a gravitational wave detector by looking at how the gravitational
waves ripple across pulsars. It's really super interesting. One of
the most fascinating things to me is that we actually
don't understand how these supermassive black holes merge. Like theoretically,
it's a little complicated when they get really close together.

Speaker 2 (14:46):
I mean, when they get really close together, I guess
I would just assume that they like attract each other
and just like pull each other into each other.

Speaker 3 (14:53):
Or is that too simple?

Speaker 1 (14:54):
No, you're exactly right. And if they're heading right towards
each other, boom, they just suck into each other. But
remember they're moving asked already, and if they're not exactly
angled at each other, they're gonna end up orbiting each other. Right,
there's gonna be angular momentum. They're spinning around each other. Basically,
if one black hole passes by the other one instead
of hit directly hitting it, it's gonna swing around and

(15:14):
the two are gonna end up orbiting each other. Now,
if those black holes are surrounded by a bunch of
other stars, then they're gonna lose energy and they're gonna
fall towards each other. And you might be thinking, well,
what about the gravitational radiation is not gonna sap the
black hole's rotational energy so that they end up falling
towards each other. Yeah, that's true. That happens, but that's

(15:34):
not a lot of energy. It's not fast enough to
explain how they actually fall together. What they need is
the friction, the tugging from stars and gas and dust
to slow them down and help them fall in. Gravitational
waves are not enough. But when they get really close
and there's no other stars and it's just two black
holes orbiting each other, we don't understand why they eventually collapse.

(15:56):
We think that's a stable situation, like two black holes
orbiting each other with out any stars to slow them
down or whatever, they should do that for a long
long time, we don't really understand why they close that
final gap. We know that it happens because we've seen
evidence gravitational waves from those mergers, but theoretically it doesn't
quite make sense. It's called the final parsec problem. It's

(16:17):
still an open question right now in physics.

Speaker 2 (16:20):
And I'm assuming that we don't have a lot of
these instances where you have two black holes orbiting each
other that you can look at to try to get data,
because that's probably a pretty rare thing to see.

Speaker 1 (16:30):
It is hard to see because super massive black holes
are in galaxies far far away, and it's very difficult
to see these things and observe them, and the timescale
of these things is very, very long, so we have
not yet detected individuals supermassive black hole mergers. What we've
detected with these gravitational wave observatories that span the galaxy
is like a general hum from lots and lots of them,

(16:52):
so we know that it's happening. But if we can
get data from an individual and you're absolutely right, and
track like what's happening over those last few seconds, we
could learn a lot about how these things collapse. And
so it's something we haven't understood. But still now to
answer Chris's question, now that we have sort of the
background on like how these galaxies merge and how the
black holes mysteriously merge, even though don't quite understand it,

(17:13):
Chris is basically asking, if the Milky Ways made up
of all these galaxies, and those galaxies have black holes
and they merged, why don't we see a bunch of
black holes at the center of the galaxy instead of
just one right, And the answer is that the Milky
Way hasn't had a big collision recently for some reason.
The Milky Way is pretty smooth and chill. There hasn't
been a lot of activity. So if we had recently,

(17:35):
in the last you know, a few hundred million years,
collided with a big Mama galaxy, then yes, we probably
would have two supermassive black holes at the center swirling
around each other and we could watch it happen and
maybe learn something about this final parsec problem. But we're
sort of lucky, I guess, in that over the last
few billion years we haven't had as many collisions, which

(17:55):
is probably one reason why we're not as big. Like
if you look at Andrama, the nearby galaxy much bigger
than the Milky Way, it's a big Mama galaxy and
pretty soon at you in a few billion years, we
are going to collide with it and form some super
duper galaxy. But we're I guess a little bit quieter
and a little bit smaller, and that's the reason we
don't have surviving multiple super massive black holes at the center.

Speaker 2 (18:17):
And just to be clear, the physicist in you would
really like to be around when our galaxy merges with
another m H but Kelly and her children would not
want to be around because that could be a very
chaotic time.

Speaker 3 (18:28):
Is that right?

Speaker 1 (18:29):
That would be a very chaotic time. Yeah, exactly. You know,
even though it would be far away, like the collision
of two galaxies doesn't necessarily involve a collision of stars directly.
It's a lot of gravitational perturbation. And we talked in
a whole other episode about what that would be like,
and it's pretty risky stuff. But yes, we would learn
so much about black holes and how they work, and
how galaxies form, and the history of the universe and

(18:51):
our place in it, and it would be totally worth it.
Sorry for your children, I.

Speaker 3 (18:56):
Don't think it's going to happen in our lifetime. So
we're right.

Speaker 2 (18:58):
So let's reach out to Chris and see if this
answered his question, and then we're going to take a
break before we come back for a question about setting
off nuclear weapons in extreme weather events.

Speaker 1 (19:10):
So I sent our answer to Chris and he wrote
back to me in an email to say, quote, that
was a great discussion and a very satisfying answer. Thank you,
So thank you, Chris, and you're welcome.

Speaker 3 (19:40):
All right, and we're back.

Speaker 2 (19:42):
Our next question is from Margie, and this one is
a doozy.

Speaker 5 (19:46):
The other day I heard that a certain politician wanted
to use nuclear bombs to get rid of hurricanes. Politics aside.
Even though it's a bad idea, it made me wonder
what would happen if a nuke went off in a
hurricane blow it out? What about the radiation in the ocean.

Speaker 1 (20:03):
Thanks, this is a really fun question, and it's what
I've heard a few times people talking about. So I thought,
you know what, let's handle this out on the podcast
in case somebody out there with their finger on the
nuclear button happens to be a listener.

Speaker 3 (20:18):
H all right.

Speaker 2 (20:19):
So I thought that this was an incredible question. As
soon as I write it, I was like, oh, yeah,
I absolutely want to know the answer to this. And
you said you've heard this question before. This was totally
new to me. So let's start with how hurricanes even work.
If we want to talk about how you would blow
one out, let's know how they get started.

Speaker 1 (20:36):
Yeah, hurricanes are amazing demonstration of pretty basic physics. You know.
Its heat flow combined with the rotation of the Earth
gives you this effect. And there's a little bit of
a naming thing going on here. The broader category is
called a cyclone, and if it's in the Atlantic or
the Northeastern Pacific, then you call it a cyclone. The
same storm in the northwestern Pacific you call it typhoon.

(20:57):
And if it's in the South Pacific or the Indian Ocean,
you call it a tropical cyclone. So you may have
heard all of these terms. They're actually all the same thing.
They're all just cyclones. Hurricanes are like our version of them.

Speaker 3 (21:08):
Why why did they do that?

Speaker 2 (21:09):
Were they described by different groups living in different areas
at different times and those names just stuck or science
sometimes goes a little crazy with our jargon.

Speaker 3 (21:19):
Is that what happened to here?

Speaker 1 (21:20):
It's actually really fun because we're not one hundred percent
clear why we have three names. I mean, the most
likely general explanation is the same reason why we have
like multiple names for carbonated beverages coke or soda or pop.
They originate in different groups organically, and then it becomes
hard to reconcile once we realize, hey, these are all
the same thing. We think the word hurricane comes from

(21:42):
the Caribbean god Hourcan or the Mayan god of wind hurrican.
I might be mispronouncing those, and then the words were
later adopted by Spanish colonizers. The word cyclone comes from
the Greek word cuclos, which means circle. It was coined
in eighteen forty by Henry Pittington of the East In
Company to describe storms in the South Pacific and typhoons.

(22:04):
That word doesn't have a clear origin. It might be
from the Greek name of a monster associated with the wind,
or a Persian word that means to blow furiously, or
we don't know exactly where that word comes from. We're like, oh,
that's actually the same thing. You call it a hurricane,
we call it a typhoon. Let's call the whole thing off.
But you know, sometimes in science it's more dramatic than that.

(22:25):
There's like competing groups and we think it's called the typhoon,
we call it a hurricane. And then you know their
minions propagate this kind of stuff. And we had an
event like that in particle physics, were the same particle
named by two different people, And these days we give
it both names because we couldn't settle the debate.

Speaker 2 (22:41):
We have species descriptions like that. Two people didn't realize
they were naming the same species. But whoever got their
paper published first has precedents. I think maybe it differs
by field. Maybe the person who did it better. But anyway,
I've been reading papers from the nineteen hundreds and sometimes
they even do name calling and stuff. It's intense, but okay,
all right, so different names, it's all cyclones.

Speaker 3 (23:01):
You say tomato, I say tomato.

Speaker 1 (23:02):
Yeah, exactly what causes them? So a cyclone basically comes
from warm water. It heats and moistens the air above it. Right,
so the ocean is warm, you get hot air above it.
That hot air rises. That causes low pressure because the
air is going up. So now more air is going
to move in. So you have this effect where air
is getting sucked in and pushed up.

Speaker 5 (23:24):
Right.

Speaker 1 (23:24):
The second step is to get it to spin. The
reason it's spinning is because the Earth itself is spinning.
And this is super fascinating. It comes because the atmosphere
at different latitudes is spinning at different velocities. Like think
about how fast the atmosphere is moving at the poles
where the Earth is spinning. It's just in place, right.

(23:45):
An air molecule above the north pole is not moving anywhere.
But an air molecule above the equator it's sticking with
the land. It's going a lot faster, right, So the
air velocity depends on the latitude. The closer yurdit equator,
the fast you're going, the closer yard of the poles,
the slower you're going. All right, that's cool. Now, what

(24:05):
happens if you're sucking air in imagine this cyclone. We
have a low pressure region, we're sucking air in from
the north, and we're sucking air in from the south. Well,
the air that's coming from the south, if you're in
the Northern hemisphere, is going to be moving faster, and
the air that's coming from the north is going to
be moving slower. So the air moving from the north
is moving slower, it falls behind. The air moving from

(24:26):
the south is moving faster. It gets sped up, and
that's where the spin comes from. And that's why they
spin the opposite direction. In the Southern hemisphere toilet thing exactly,
the famous fallacious toilet thing. But this is actually true, right,
if you could flush your toilet with a hurricane, it
actually would flush a different direction in the northern Southern hemisphere,
except you couldn't call it a hurricane. You could call

(24:47):
it like a tropical cyclone in the South Pacific. So yeah,
in the northern hemisphere, they spin in a different direction
and in the southern hemisphere. Super cool.

Speaker 2 (24:55):
Okay, And let's be clear for anyone who missed that
toilets do not flow opposite directions in different hemispheres, because
it's all about the way the holes are put in
the toilet, see right, and that just makes it go
in one direction.

Speaker 1 (25:08):
I have no idea how it actually works. I just
know that it's apocryphal. Okay, Yeah, But so that's the
basic mechanism or hurricane, right, starts with warm water, you
get air rising, air rushes in from the sides. It's
coming in at different speed, so it ends up spinning.
So it's spinning because the Earth is spinning. Like if
the Earth didn't spin, we wouldn't have hurricanes or cyclones
or typhoons or any of that kind of stuff.

Speaker 2 (25:30):
Okay, So ways to disrupt this weather pattern would either
be to like mess with the temperature or to like
put a giant fan in there trying to counteract the spin.

Speaker 3 (25:41):
But we're talking about nukes, so nukes would heat things up.
Could that stop it?

Speaker 1 (25:45):
I love the idea of using nukes because it's like,
what's the biggest thing we got? We have this hammer?
What can we do with it? I mean, you see
this in space all the time. People are like, how
do we power spaceship? What if you blow up nukes
behind it? And that's actually not a crazy idea, right,
We're going to talk about that pretty soon the podcast.

Speaker 2 (26:01):
Well in Project Cloudshares was a whole project in the
US to figure out what you could use nuclear weapons for.
We use them to build like bays and stuff like that, Like,
let's blow that up too, Okay, So anyway, what about
a hurricane?

Speaker 1 (26:13):
So it's not completely insane on the face of it,
because what is a hurricane? You have a hotspot. It's
all about energy flow, right, This warm air heated by
the ocean is rising and all this stuff is coming in.
So if you could like disrupt that somehow, if you
could create hotspot somewhere else, or move the heat or
disperse it or something, could you disrupt this flow? So
it's not insane, right, It's not just like, hey, I'd

(26:35):
love to nuke that, let's do it. But the problem
is that hurricanes a our energy flow on a much
much bigger scale than even our nuclear bombs. Like there
is so much energy captured in a hurricane. I looked
it up. Hurricanes release like one hundred tarawatts of energy,
and the global power use annually is twenty five tarrawats.

(26:55):
So like, this is an enormous amount of energy. It's
four times as much as like human use.

Speaker 2 (27:01):
Okay, so the biggest nuclear bomb ever exploded was by
the Soviet Union.

Speaker 3 (27:06):
It was tzar bomba right, mm hmm. How does that compare?

Speaker 1 (27:10):
So you would have to blow that guy up every
twenty minutes to compare to the energy of a hurricane. Wow,
So it's a big deal. Like a hurricane is just
a massive movement of air. It's because the mass. Well,
there are high speeds as well. You know, these winds
can get to hundreds of miles per hour, but it's
just such a huge mass. I mean, you can see
the things from space, right, it's big. And anytime you

(27:32):
have something really big moving high speed, there's a lot
of energy and it would take an enormous amount of
energy to deflect it. So if you're going to nuke,
it's going to require like all of the Earth's arsenal
dropping down on this thing. It's not like a single
tactical nuke is going to deflect this thing. You want
to have an impact, it's going to have to be huge,
and then you're causing a nuclear winter. So I don't

(27:53):
think you really accomplish an.

Speaker 2 (27:55):
You haven't solved any problems there. We started by saying
that cyclones are because of heat. Is it possible that
by trying to stop a cyclone when we set a
nuclear weapon off, we're just gonna make it worse because
that's more heat. Oh yeah, is that what would happen
or we don't know if it would get worse.

Speaker 1 (28:12):
Well, hurricanes are not something we totally understand right anyway.
We can't like look at a hurricane and say we
know what's going to happen here because we understand all
the physics. We understand the microphysics, but it's such a
chaotic system that a little wrinkle here, a butterfly flaps,
that swings there, the hurricane goes somewhere else. These things
are difficult to model. We think that probably what would
happen is you'd produce a shockwave a pulsive high pressure,

(28:33):
but we don't think that would actually have a big
effect on like the pressure of a hurricane. In order
to change like a big category five hurricane, you do
a category two hurricane. You'd have to add like a
half ton of air for each square meter inside the
eye of the hurricane, which is like five hundred million
tons of air. So you know, it's hard to imagine

(28:55):
like moving that much air around in terms of like
changing the pressure. We don't have like the tool to
do this right. And you know, fundamentally, like you have
a big warm spot in the ocean, unless you're going
to completely disperse that heat, you might temporarily disorganize a hurricane,
but the same forces that create it are just going
to reorganize it. I mean, as you say, like you're

(29:16):
adding heat usually to the system, and so it's just
going to come back stronger, you know, like a monster
in a terrible movie. Plus you're gonna have like dumped
a bunch of radiation into your atmosphere, a very high
velocity winds that are going to go everywhere, all right.

Speaker 2 (29:31):
So you have just made me even more amazed that
there are some people who don't evacuate when hurricanes come through,
because I hadn't realized how much stronger they were than
the explosions of nuclear weapons. We've established that heat equals
bad in this case, can you cool it down?

Speaker 3 (29:48):
Somehow.

Speaker 2 (29:49):
I'm guessing the answer is no, because this is just
energy on a scale that is uncontrollable. Yeah, has anyone
ever tried to like cool it down?

Speaker 1 (29:56):
So the US government has sponsored a bunch of projects
to try to in your with hurricanes, which makes sense,
like these are destructive things. Is there anything we can do?
And in the sixties there's this project called storm Fury,
which is a pretty awesome name, where the thought was,
could we somehow disrupt the flow because the hurricane has
these walls as of clouds circulating around the center, And

(30:18):
they thought if they maybe seated the clouds by dumping
in a bunch of silver iodied, which nucleates ice crystals,
that this silver iodied would make these ice crystals, which
could make like a new ring of clouds, which would
somehow compete with the natural circulation of the storm and
basically disorganize it, sort of actually releasing some of the
heat by forming these ice crystals, right, releasing some of

(30:40):
that water, and then like growing the rainy part instead
of this spinny part. The idea was sort of reasonable,
and they actually tried it on a few hurricanes, but
it didn't work. And these days we think that probably
it failed because there isn't enough super cooled water to
react with that silver iodide to have enough of an effect.
And so people have tried stuff, nobody's ever made it work.

(31:02):
But you know, people are out there thinking about how
can we protect ourselves from hurricanes? What are some things
we can do? To me? This is kind of scary.
It's in the category of like geoengineering, right, like, hey,
should we put something in our atmosphere to reflect sunlight?
Like you're dumping a lot of stuff into a storm.
It could have a big effect. You have no idea
where that storm is going to go, and then you
feel responsible for it. Right What if the storm was

(31:24):
going to hit a fairly uninhabited area and then you
steered it towards New York City, Now you're responsible for that.
So I don't know whether it's a good idea or not.

Speaker 3 (31:32):
I don't know either, you know.

Speaker 2 (31:33):
I actually I love to have a whole episode on
geoengineering stuff because it is so tempting. What if there
was some way that we could all just keep doing
exactly what we're doing, but just like throw some stuff
in the sky to take care of it. But yeah,
I don't think we understand things well enough.

Speaker 1 (31:46):
Yeah, but they did, and in the sixties they did
it for Hurricane Esther and Hurricane Bulah, Hurricane Debbie, and
then Hurricane Ginger in nineteen seventy one. I wasn't able
to find more recent experiments. I don't know if those
are like still classified or whatever, but it's definitely something
people tried. Nobody's ever tried a nuke a hurricane as
far as I'm aware, which I'm grateful for. Though I

(32:06):
know that our president elect it's an idea that he
bounced around within his previous administration.

Speaker 2 (32:11):
Well, I hope he listens to our podcast and we
can help out in that way.

Speaker 1 (32:15):
I also remember seeing videos during some recent hurricane in
Florida of people shooting the hurricane. It seems like, I
get what you're expressing your frustration and this is the
only tool you have, But like, you don't want the
hurricane picking up those bullets and throwing them at high
speeds at anything. So don't shoot hurricanes people with nukes
or with bullets or really anything. Just get out of there.

Speaker 3 (32:37):
Yeah, don't contribute to the problem.

Speaker 1 (32:39):
Just leave.

Speaker 2 (32:40):
That's sound advice there. So let's see what Margie thinks
of our sound advice and see if she felt like
this was a good answer.

Speaker 1 (32:48):
Maybe we can convince her to slowly slide her finger
off of that big red button.

Speaker 2 (32:54):
I wonder how much power Margie has, Sparis Margie. All right, Well,
here Margie's response, and then we'll take a break.

Speaker 6 (33:02):
Wow, I'm a little surprised that it would just reform
after a blast. But let's say a nuke was shot
off in a hurricane in the middle of the ocean
and then it started spreading radiation.

Speaker 1 (33:15):
All over the place.

Speaker 6 (33:17):
Would it still be spreading radiation when it came ashore.

Speaker 1 (33:22):
Very glad we were able to answer your question, Margie,
And that's a great follow up question. Yeah, it would
be very bad to release a lot of radiation into
a hurricane. The sort of long range danger from a
bomb going off is exactly having high winds which spread
those radiactive materials around, and so dropping one into a
hurricane it's basically the worst case scenario for containing that radiation.

(33:45):
So yeah, the winds in the water would spread that
radiation really far and cause a lot of damage. Again,
not a good idea. Please don't drop a bomb into
a hurricane.

Speaker 2 (34:15):
So Our next question is from Kevin, So here we go.

Speaker 7 (34:20):
This is a Kevin from Shoay, China, and I'll have
a question about philosophy. If a photon turns into the
electron and a positron, and the electron and positron and
wiolates into another photon, are the two photons exactly the same?
If they are the same, how can the photon appear
and disappear out of the air. And if they are

(34:41):
the same, is there a point when the first becomes
a second?

Speaker 1 (34:45):
Ooh, thank you Kevin for asking such a fun physics
slash philosophy question.

Speaker 2 (34:50):
Totally love this one, and I absolutely love hearing that
we have international listeners. This totally made my day. And
Daniel is clearly the right guy to answer your question.
So what's happening Daniel?

Speaker 1 (35:00):
So what's going on here is that photons, when they
fly through space, you might just imagine like, hey, it's
a little packet of energy. It wiggles through space. That's it, right,
But we also talk about photons doing other stuff, like
photons can fly along and then we say sometimes they
can turn into a pair of particles called this conversion.
Like a photon is flying along and it turns into

(35:21):
an electron and a positron, two particles, so maintaining the
overall charge of zero, and then those particles can annihilate,
they can turn right back into a photon. So you
can imagine like either just a photon flying along which
turns into like a little loop of particles and then
turns back into a photon. And Kevin is asking, like,
what does that mean about the photon? Is that the

(35:43):
same photon that comes out after this particle loop or
is it not? And if it's not, then like, exactly
when does the new photon get born?

Speaker 2 (35:53):
So is this philosophically the same as the transporter problem.

Speaker 1 (35:57):
It's actually very similar to the transporter and it touches
on you know, what do you mean by this photon?
And how do you kill a photon? And all sorts
of stuff, and because in the end, these are quantum processes, right,
And the transporter problem in the end comes down to
like any time an object moves from place to place,
it's equivalent to making a copy of it and destroying
the old one, especially if we're all just ripples in

(36:19):
quantum fields, it's just your information sliding along. And so
basically every moment in your life. You're being transported through
space and time the same way a teleporter works, just
smaller distances. And so yeah, does that matter? Are you
being killed every instant and being recreated some other place?
What does that mean about being killed? I don't know anyway,
it's a big rabbit hole of philosophy. But here we're

(36:42):
focusing on a single photon.

Speaker 2 (36:43):
Okay, so you're not going to answer that question for
us by the end of this answer. What do we
mean then by same If it's the same photon, what
would that mean?

Speaker 1 (36:52):
Yeah, so there's two issues here we have to grapple
with if we're going to think about what this means,
and that's one of them. And the short answer, the
big picture answer to this question is that there is
no good answer to this question because the picture that
I just described, and that Kevin probably has this head
and a lot of people think about for photons, it's
a cartoon picture. It's not like our microphysical explanation for

(37:13):
what's really happening. Like you know, in biology, you can
have a microscopic explanation. You can say, oh, the reason
you're sick is a virus came in and attacked your
cell and to penetrated the cell wall, and you can
have this picture in your mind of these tiny things
happening that explain what we're experiencing on the big scale,
and that can be reality. So if you like zoom
in with a microscope, you can actually watch it. That's awesome, right,

(37:35):
And we try to do the same thing in physics,
provide a microscopic explanation for what we think is happening,
and that can be very satisfying, but it's sometimes a
cartoon and it's misleading because what's happening in the microscopic
scale is fundamentally, very very different from what's happening in
biology or in the classical scale. It's not like tiny
little balls or bouncing off each other or converting into particles.

(37:57):
You can't slow these things down and watch them like
a movie and get a version of the microscopic story.
So you know, what we mean by a photon isn't
just like a photon is flying through space, or a
photon flies through space and makes a particle loop. It's
sort of all of those things mixed together. So that's
why we have to identify what we mean by a
photon and what we mean by same.

Speaker 2 (38:17):
So does this go back to our what is a
particle discussion? And do they work as waves or strings
or so? The question is hard to answer because we
don't even really know how to describe these things.

Speaker 1 (38:29):
Yeah, exactly, and Kevin is picking out one aspect of
that cartoon, and really a photon is all of those things.
So let's start by talking about what a photon is,
and then we can dig into what do we mean
by the same photon. Okay, if you think about a photon,
it's just you're thinking about a single packet of light
that goes through space quantum mechanically. Kevin is right that
the photon could do that, but it could also convert
into these par of particles and go back. It could

(38:51):
also convert into those pair of particles, and then those
particles emit photons, which then turn into other stuff and
turn into other stuff. There's an infinite number of things
that a fon could do when it goes from A
to B, and each of those things comes with a probability.
And when we talk about the photon, we don't mean
one of those particles in one of those stories. What

(39:12):
we really mean is that whole bundle. We mean the
whole thing all mixed together because we don't know what's happening,
and there is no what's really happening the photon. The
thing we think about, the thing we should identify with
is all of those possibilities, not any individual one of
them or any part of them.

Speaker 2 (39:28):
So when we were doing the what is a Particle episode,
we talked about how you don't explain the wave theory
of how you describe particles until grad school. And so
this question is making me wonder how the fact that
we are all taught to think about these as like
little points that are moving around, how much does that

(39:49):
inhibit all of our abilities to think about these things?
Like should we be changing the way we address this
in high school? I know it's much harder to explain
it as a wave, but it's wrong. It sounds like
the way we explain it.

Speaker 1 (40:02):
Yeah, quantum field theory in kindergarten. That's what I think. No,
it's a great question, and I think you're right, And
you see it in physics students as they learn this stuff,
you teach them to think about particles and then you're like, actually,
all your intuition is wrong. You have to unpack that
and learn this whole other thing. And you know, I'm
very interested in physics education. We have these conversations like
what is the right order to teach people in, But

(40:24):
there's sort of this canonical order that everybody uses that
sort of follows the historical development. It's like, we thought this,
then we thought that, then we thought that, And as
you move through your physics education, you sort of catch
up to modernity. And I think it is important to
understand where these ideas came from, like why people thought
this and why people thought that, because just like with

(40:44):
the names of hurricane and typhoon, there's a lot of
like weird, patchy stuff that doesn't really make sense unless
you understand the history. So you kind of got to
teach people the current ideas, but you also want to
give them a tour of how we got here so
they can understand why some of it seems weird and ugly.
So I don't know the right answer to your question.

Speaker 2 (41:04):
Okay, I mean I see no reason why we couldn't
start with here's the wave theories and string theories of
particles and then after be like, well, here's the history.
Let's talk about how we got here m hm, so
that people would be less confused. But anyway, I'm not
a physics educator, but I guess I kind of am.

Speaker 1 (41:20):
Yeah, I guess that we have opinions at least. So
in that episode about a particle, we also talked about
how you can think about particles, as you know, little
dots flying through space turning into other stuff. You could
also think of them as fields. Right, instead of imagining
a bit of stuff, imagine a field feeling the universe,
and particles are ripples in those fields, and those two
things are actually mathematically equivalent. You can think about everything

(41:43):
as particles and they pull on pushing each other by
passing other particles between them, or you can think of
just fields and energy is flowing between the fields. And
I think the field's picture is really helpful to think
about for this question, because what we're talking about is
not just one part of it's a particle interacting with
another particle, right, Photons turning into electrons and back and forth.

(42:05):
And in the field picture, that's kind of beautiful. What
we see there is two fields interacting like a photon
as it flies through the universe is not just a
ripple in the electromagnetic field, as we say, because the
electromagnetic field affects the electron field, and vice versa. So
when you say in the particle picture, okay, a photon
is flying along and you can turn into an electron

(42:26):
and positron and go back in the field picture, that's
the same thing as saying energy can slash from the
photon field to the electron field and back. And what's
really happening is not that there is an electron there
or there is a photon there. But the thing we
call a photon is this interaction between the two fields.
So that's the problem with putting your finger on like
is it the same photon? Well, what do you mean

(42:47):
by a photon? Do you mean just the electromagnetic field,
like theoretically pure concept, or do you mean the thing
we see in the universe, which is like buzzing interaction
between photons and electrons or the photon and electron fields.
That's really what a photon is. A photon that hits
your eye from Andromeda has interacted with the electron field
all the way between there and here.

Speaker 2 (43:06):
Okay, can we give a two sentence answer to summarize.

Speaker 1 (43:10):
Yeah, So what is a photon? A photon, I think
is all the possible things that could happen between A
and B, and when the photon is created and the
photon is observed, you can't really dig into what happens
in between because there are multiple possibilities and all of
them play a role. Right. So now, so Kevin's question,
what do we mean by the same photon? Well, you know,
I think that you can't really think about those individual

(43:32):
photons and say is it the same? And if you tried,
you get yourself into all sorts of other hairy misses
that we touched on earlier, Like think about an individual
photon not just flying through space, but like bouncing off
of a mirror. What happens when a photon bounces off
of a mirror, Well, we think it's absorbed and re
emitted at the right angle. Is that the same photon? Well,

(43:52):
you know, it's like if you shine a light in
the mirror, the light hits your eyes. We think of
the light as bouncing off and hitting your eyes, but
it's been reabsorbed and re emitted. Is that the same?
If you say that's not the same, that means that
every time particles interact, they're no longer the same particle.
But particles are interacting constantly all the time. You are
a huge pile of particles interacting, which means that you

(44:12):
were not the same you were a millisecond ago. So
that leads nowhere. If you say that particle interaction means
they're not the same particle anymore, then you have no
useful meaning for the word same. Then you have to say, well,
then maybe a particle is the same if it's like
mostly unchanged. You shot the photon at the wall, it
bounced off, and it's mostly the same energy and the
same frequency and all that kind of stuff. So it's

(44:34):
mostly the same photon even though it's interacted. So from
that point of view, then the answer to Kevin's question
would be like, yeah, it's the same photon. And I
think philosophically unpeeling it. It's a big blob of energy.
It's flowing through the universe. It's oscillating between the different fields.
It doesn't really matter. That has a chance to be
an electron here and a chance to be a photon there.
It's the same blob of energy that was sent to

(44:54):
you from Andromeda. So I think it's the same photon.
So does that make sense to you, Kelly? What do
you think.

Speaker 2 (44:59):
Yes, all right, that makes sense to me. Here, let
me see if I can explain it.

Speaker 3 (45:03):
Okay.

Speaker 2 (45:04):
So the reason that it's a complicated question is because
it's hard to think of a particle as like a
point in space. They're like packets of energy that are
interacting with other packets of energy, and they can be
hard to describe.

Speaker 3 (45:17):
You know, they're.

Speaker 2 (45:17):
Interacting like they're a wave, like they're a string, but
they're just sort of things that are interacting with other things,
and that's what they're doing all the time. And so
to try to figure out is this the exact same
thing when part of how we understand it is that
these things are changing and interacting over.

Speaker 1 (45:32):
Time, it makes it an awkward question.

Speaker 3 (45:36):
Yeah, yeah, is that an okay way to summarize it?

Speaker 1 (45:38):
Yeah, I think that's great. I'm giving you a PhD
in Internet physics right now?

Speaker 2 (45:42):
Yes, right, okay, but grades are really important to me,
and I haven't gotten one in like fifteen years, So
can you tell me?

Speaker 3 (45:50):
And I got an A. Actually I kind of feel
like that was more like a B answer.

Speaker 1 (45:53):
No, that was a solid A answer. Yeah, And now
I'm curious what Kevin thinks about our answer. So in
a moment, you'll hear Kevin giving us a grade on
our physics answers to his philosophy question.

Speaker 7 (46:05):
Hi Janyan Kelly, thank you for answering my question. I
think you mean that a photon is quantum mechanical, so
it's a mix of the probabilities of all the possible
things that can happen. Also, depending on the meaning of saying,
the photon is the same and not the same at
the same time, which is mind boggling. I totally love

(46:27):
these kinds of answers.

Speaker 2 (46:29):
Thank you so much to Chris, Margie and Kevin for
their amazing questions today. We had so much fun thinking
about these problems. And if you have a question that
you would like to share with us, please write us
at questions at Daniel and Kelly dot org.

Speaker 3 (46:42):
We would love to hear from you.

Speaker 1 (46:44):
We would and your friends will be so impressed to
hear your voice on a podcast, especially a nerdy podcast
like ours.

Speaker 3 (46:51):
Huzza.

Speaker 1 (46:51):
Thanks everyone, keep asking questions and stay curious.

Speaker 3 (46:54):
See you later.

Speaker 2 (47:02):
Daniel and Kelly's Extraordinary Universe is produced by iHeartRadio.

Speaker 3 (47:06):
We would love to hear from you, We really would.

Speaker 1 (47:08):
We want to know what questions you have about this
extraordinary universe.

Speaker 2 (47:13):
We want to know your thoughts on recent shows, suggestions
for future shows.

Speaker 3 (47:17):
If you contact us, we will get back to you.

Speaker 1 (47:20):
We really mean it. We answer every message. Email us
at Questions at Danielankelly dot org, or.

Speaker 3 (47:26):
You can find us on social media.

Speaker 2 (47:28):
We have accounts on x, Instagram, Blue Sky and on
all of those platforms.

Speaker 3 (47:33):
You can find us at d and kuniverse.

Speaker 1 (47:36):
Don't be shy right to us