- This is StarTalk and I'm
your host Neil deGrasse Tyson,
your personal astrophysicist.
And today's edition of
StarTalk is cosmic queries.
Whatever the hell came off the internet,
that's what we're doing today.
And my cohost today, Sarah, hello.
- Hello Neil.
- First time
we're doing this together.
- First time,
and I hope that I get initiated.
I hope that there's some sort
of weird induction process.
- And you got a whole
comedy background, right?
- You have a whole comedy background.
- With the Harvard Lampoon.
- I was at Harvard, I
did not do the Lampoon.
- You didn't do the Lampoon.
- No, no, you know,
they were jerks when I was
there, so they didn't take me.
- Is that how that works? (laughs)
- That is how that works.
Actually they year that
they don't take you
they become jerks.
- Oh, oh.
- It's a weird bylaw of the organization.
- Okay, so we're getting
the Lampoon rejects.
- (laughs) You've reached that low point.
- That low point.
- No, actually
my dad was on the Lampoon
and I didn't want to join
for that--
- You have a comedic dad?
- I--
- So what is a dad joke
of a comedic dad?
- Oh my God they're worse--
- Are they better or are they worse?
- They're so much worse they're so much--
- (giggles) I get accused of dad joke,
I just say something I think
is kinda funny on Twitter.
Thanks dad, you know. (laughs)
It's like, how did they
know, how do they do this?
I'm thinking I'm being clever,
but I'm just being a dad.
- At least you have jokes.
There's no mom joke territory.
- That's true.
- Yeah, what's that about?
- I don't know.
- I'm just sayin', standards here.
- 'Cause the weight of the world
is on the shoulders of moms.
- Yeah.
They don't have time to joke around.
They ain't got time for that.
- Not a joking matter.
So as usual these questions
are collected from our internet fanbase.
- Yes.
- From Instagram, Twitter.
- Facebook.
- And Facebook, very cool.
- A guy on the street.
- Yeah.
- It's totally legit.
- And I don't know if you're
better at pronouncing people's
names than Chuck Nice.
- Oh. (laughs)
- We'll decide that
in this episode.
- Yeah, we'll see.
I'm just gonna say it
loudly and confidently
and I think it'll be convincing.
- Even if it's wrong it's confident.
- Yeah, exactly, I mean, they don't know.
They're not gonna bust
in the door and be like--
- No one else will know, you'll mean.
They'll know, no one else will know.
- Yeah, they'll know.
- So what's the first question?
- All right, so the first
one actually has a guide
to pronouncing the name,
it comes from Yaneev Kass,
our Patreon Patreon,
and his name he says--
- They will get their
questions answered first.
- Oh yeah, no, yeah.
- Just buy this right.
- First class citizens, absolutely, yeah.
Blessed be his name, Yaneev
is pronounced like Yaneev
and it rhymes with achieve.
That's what it says on the question.
- Yaneev, good, mm-hmm.
- Although he addresses it
to Chuck, which I'm gonna
take as a personal insult.
So my question to Dr. Tyson, are we near
the center of the universe,
and as a personal follow-up,
is that center as I've long suspected me.
- Ooh, ooh.
- Yeah.
- That's your follow-up.
- That's my follow-up,
but his is just about the center was--
- You're the center.
- I made it better.
- Sarah, you are the center
of your own universe.
- Oh, thanks Neil.
All right, that's it, interview's over.
- But you're not the center
of anyone else's universe,
nor the universe itself.
- All right, well...
- So yeah, the universe has no center.
And just because you can put
the noun and verbs together
to make a sentence that sounds
like it should have an answer
where is the center of the
universe, are we there?
Does not require that it has an answer.
For example, here's a question
that you know not to ask.
Where is the center of Earth's surface?
Unless you're a flat-earther
and think we have a disk
which would have a center.
- Which we all know you're a big fan of.
- Big fan, but this spherical Earth,
you know to not even ask that.
- Yeah.
- You know this, so it turns
out the universe has no center
because everything in this universe
was at the same place at the same time,
and we call that the big bang.
So it kind of had a center,
but it's not accessible today.
You have to go backwards
13.8 billion years
and the whole universe was at
its own center in that moment.
- It's interesting 'cause
a lot of the questions
actually were kind of off this topic,
and somebody even said explicitly,
I can't imagine the universe
as anything but a sphere.
It seems almost innate that we think of it
as like a physical space with a center.
- Yeah, but that's fine, I'm just saying
one way to visualize this is to take away
one of the dimensions because
our brains are too feeble
to imagine four dimensions
or five dimensions,
is take away a dimension
and put the whole universe
on this surface of a balloon.
- Uh-huh.
- You draw little spiral galaxies.
If you inflate the
balloon all the galaxies
get farther away from all other galaxies.
And if you were on a galaxy you would say,
are we at the center?
No, where is the center?
Are you at the center?
Nobody gets to say they're
at the center, you know why?
Because the center is not on that surface.
The center is when the
balloon was smaller,
when the balloon was infinitesimal
13.8 billion years ago.
And when that happened,
everybody was at the center.
- So I was at the center then.
Okay, that's all I needed to know.
- At that one moment in the past.
- That's all I really needed
to know, thanks for confirming.
- Allow me to remind you.
- Yeah.
- That the opening quote
of my current book,
"Astrophysics for People in a Hurry"
which is a really cheap
plug for that book,
but I have to say this.
- Yeah, I have to say,
I grade that a C of a segue.
- A C minus, C plus.
- Yeah, yeah. (laughs)
- I opened it with,
I just have to set you straight and say,
the universe is under no
obligation to make sense to you.
- Oh yeah, I remember that.
I love that introduction.
- Yeah, that's all it is.
And I put it in that book
printed for the first time.
- Yeah, no, that was a
fantastic introduction
'cause it was touching on a feeling
you didn't realize you had.
- Mm, ooh, I like those.
- Yeah, no, absolutely.
- Very good.
- It really tugged at that emotion.
Okay, moving on to our next question.
This one comes from a user
named Alimiamcd98 on Instagram
who says, if all galaxies in the universe
are expanding away from
us, then what is the cause
for the Andromeda galaxy
being on a collision course
with our own?
- Excellent question.
- I know.
- Beautiful, that's beautiful.
So let's go back to our
rubber sheet analogy,
and a moment ago it was
the surface of a balloon.
Let's just put us all on a rubber sheet.
And you have this rubber
sheet that's expanding.
So you're my neighbor galaxy,
and you're my closest galaxy.
Let's say you move away from
me at one inch per second,
let's say, you'll look
to your neighbor galaxy
and you'll see it move away
from you at one inch per second.
It will see its neighbor
galaxy move away from it
at one inch per second.
I will see your neighbor
galaxy move away from me
at two inches per second.
I will see that galaxy's neighbor galaxy
move away at three inches per second.
So the farther away you are
from any point of observation,
the faster is the measured
expansion 'cause everything
is expanding uniformly
and it just adds up.
- I thought everything was accelerating.
- That's another level on top of this.
- That's over time.
- It's on top of this
that's happening.
- Oh, okay, I see.
- But that will neither, we
don't need to reference that now
to answer his question.
- I see, okay.
- So basic expanding
universe, we are expanding.
- Mm-hmm.
- Okay, so,
in other words, if you evoke that,
then as you go back in time you would see
that the expansion was greater, okay,
as the time had moved
because as you look out
in the universe you are
looking back in time.
- Right.
- So you see things
not as they are, but as they
once were, it's beautiful.
- That is gorgeous.
- Beautiful, in fact,
there was an Italian movie
called La corrispondenza.
- Could you say that a couple
more times, please? (laughs)
- (laughs) La corrispondenza.
- Could you leave that as my
voicemail message, please?
- And it starred Jeremy Irons.
- Okay.
- And was a love story.
- Big fan already.
- Me too, I'm a big fan of his.
- Yeah.
- It was a love story
and he played an astrophysicist.
And he had a--
- No wonder you liked it.
- He had a terminal
disease, had to go abroad.
His love interest did not know he was ill
and he actually died, but
he had preloaded letters
to arrive to her long after he died
so that his spirit, his
energy would still be alive
in her heart, and this was
analogized to starlight.
The star may have died, but its light
continuing to travel through space
reminds you of its continued existence
long after it is gone,
corrispondenza. (laughs)
- I was about to say, could I
get that name again. (laughs)
That is absolutely gorgeous.
- Yeah, yeah, so beautiful.
- So the key to immortality
is just send a bunch of mail
that gets super delayed.
- Wait.
- So the post office when
they're delayed in their mail,
they're just like, we want
to extend your legacy.
- Yes, yes.
- Because of the delay.
- They're doing it on purpose, yes.
- Yeah, right, exactly.
You know, the question was asking
about reference points of expansion,
but I feel like I since
graduating from college
see my own reference point as expanding,
like I am expanding away from myself.
- Oh.
- Ipso facto,
everything is expanding.
- Well so you expand
from what you once were
provided you view college commencement
as the beginning of learning
rather than the end.
- That's true, I mean, isn't the last,
the graduation speeches
are called commencement,
which means beginning 'cause
you're supposed to be--
- Well, the whole celebration
is a commencement.
- Right.
- And then there's
a commencement speech, so it's
intended to mean beginning.
- Right.
- And you would know
there's a gate at Harvard
where if you enter Harvard Yard.
- Oh, would I? (laughs)
- Through that gate.
As an undergraduate you were there.
- Yeah.
- One of the gates says,
enter to grow in wisdom.
- Yes.
- Have you read the
other side of that gate?
- Leave to get dumber.
- Excuse me. (laughs)
So it says, exit to serve
better thy country and thy kind.
- Mm-hmm.
- So yeah, you exit
and now you grow.
- I always found it ironic,
though, that there's a huge
superstition about that gate,
which is if you go through
it before you graduate
that you won't ever get to graduate,
which to me feels like a
very ignorant superstition
to have about a hate that's all about--
- That's a completely
ignorant superstition
for one of the highest
institutions in the land.
- Yeah, exactly.
- To be holding forth.
- Yeah.
- Yeah, no, I was not
into superstition.
- Yeah, but it still
pervades Harvard.
- Stupor-stition.
- Stupor-stition, I like that.
- Getting back
to your fellow's question,
so the nearby galaxy
will be receding from you slower
than all other galaxies
that are farther away, okay?
Fact number one, fact number two,
all galaxies have movement
relative to one another, okay?
And it turns out that
the movement of Andromeda
at its distance from us is greater
than the expansion of
the universe between us.
- Oh, so it's coming towards us.
- So it can overcome the
expansion of the universe
being so close to us.
If the Andromeda galaxy were
at any farther distance,
the expansion of the
universe would override it.
So generally you have
nearby galaxies colliding
towards one another.
- Right.
- Because their gravity
overcomes the expansion
of the universe, this is how
you have colliding galaxies
at all.
- Yeah.
- So it's a great question, it's a matter
of what is the distance to the object.
- It is interesting
because I was researching
the collision course
with the Andromeda galaxy
and our own, and it said the prediction
was four billion years.
- Yeah, I think
it's a little longer than that, but--
- Yeah, because that's sooner than the Sun
is set to collapse.
- Yeah.
So it's a technicality.
The systems are huge.
The Andromeda galaxy and
the Milky Way galaxy,
they're huge, so you have to ask,
when are you gonna say is the moment
that they start colliding?
- Right, right.
- What is that moment?
And so is it when the outer reaches,
the suburbs hit one another?
When their nuclei hit one another?
Or when they've settled
down into one giant mass,
double the number of stars
that the two separate systems
had to begin with, and
so if you add all that up
it's hundreds of millions of
years for the system to settle
into a new galaxy, so it's
not accurate to think of it
as a single moment in time.
- Yeah, actually NASA
has a really great animation
of what that looks like.
And it's sort of like going
out and coming back in.
- Yeah, it's a train wreck.
- Yeah.
- And so what happens is they
overshoot one another and--
- They get--
- And stars are cast
hither and yon and then they
come back and it's a mess.
And it takes a long time for
all that to settle out again.
The scientific word for that is to relax.
Relaxed systems are not chaotic.
They're actually rather organized.
And two colliding spiral galaxies,
that'll be a while
before that settles out.
So you could easily say it will begin
as early as five billion
years, but all the action
is gonna happen later, yeah.
- Okay so you're more patient.
- Yeah.
- Okay, all right.
So moving on to our next question.
Oh, I'm very excited about this one.
This one comes from
Lucas Lantz on Instagram.
- You go with Lantz and not Lantz.
- You know, I just said it confidently.
I committed to Lantz.
- Okay. (laughs)
- Because it's fancy.
- Okay.
- 'Cause it's his official--
- If he's a Brit, Lucas Lantz.
- It's Lucas Lantz and then official,
so I pronounced it officially.
- Oh, you mean it's officially recognized.
- On Instagram says--
- Say ah, yes.
- Could it be possible that a deja vu
is a phenomenon where two
different identical timelines
in two different identical
universes cross paths
and create some sort of
mental link between me
and my timeline and me in
the alternative timeline?
- Yes.
- Wow okay, and next question.
- Next question. (laughs)
- Yeah.
- I mean, I don't think we
fully understand deja vu.
- Yeah, yeah.
- Was it George Carlin
who said, "Sometimes I go into a place
"and I'm certain I've
never been there before.
"that's a vu jade." (laughs)
I think it was George Carlin.
- I like that, yeah.
- So actually, forgive me for not knowing
what the literal
translation of deja vu is.
- Yeah, it means already seen.
- Already seen, so the vu
is the seen, deja vu.
- Yeah.
- So I don't have a problem--
- With that theory.
- Hypothesis.
- Oh, hypothesis, excuse me.
- Yeah, yeah, there's
the theory of gravity.
- Right, right, right.
- Theory of relativity.
- Right.
- Quantum theory,
and Freddy's theory, right?
- I was about to say, yeah.
And Lucas Lantz' theory.
- Lantz theory.
- So I think there's
more to learn from that.
I think our brains are more complex.
We've come to recognize how
complex they actually are,
but just because something
happens in your brain
doesn't mean it is the measure
of an objective reality.
And most of human experiences do not,
sorry, most of human
curious brain phenomena
does not take root in objective reality.
So I have very low
confidence that this idea
will bear fruit.
- Yeah.
- Deja vu is intersecting
parallel universes
simply because your brain,
I could put you in a room,
throw some simple drugs into
you and you'll hallucinate.
Look at what happens to your brain
with the tiniest of chemical disruption.
You don't have a more
acute sense of reality.
You have a lesser sense of reality.
- Yeah.
- Reality is measured
by recording devices in the room
that you happen to be sitting.
No, I saw a green clown.
- Right.
- Yep, yep.
- Yeah, sure you did.
- Yep, yep, yep.
- Have you heard
of A.E. Housman's poem about a pen knife?
- No.
- He says, I need
but stick this in my heart
and down will fall the
sky and Earth and heaven
shall depart and all of you will die.
And it's about how he
thinks if he kills himself
that the rest of the world will depart
because that's what it feels like.
- I figured out that
that's what the poem meant.
(laughs)
Did you really think
that poem needed explanation?
- You see, Neil, a poem
is this phenomenon where--
- That was not one
of the obscure poems, right?
- But no, I--
- The midnight ride
of Paul Revere, this poem is
about a man named Paul Revere.
- Right, right, right.
- Who rode a horse at midnight
yeah, some poems thankfully
don't need full--
- It was for the viewer's at home, Neil!
- Explanation.
- Yeah.
- The point is.
- Yes, yeah.
- We read a lot of things,
we see a lot of things
and we don't retain active knowledge
that they sit in our memories.
We could have had things described to us
and then we make a picture
of what was described.
- Right.
- You don't have deja vu
every place you go into.
- Right.
- And you don't even have it every day.
Once a week, once a month,
a couple of times a year.
So all of the places you've been in,
surely there's gonna
be one that matches up
with some book you read,
some movie you saw.
I had deja vu, I forgot where I was.
It was Louisiana, somewhere in the South.
And I was in some conference
and we drove by a cemetery.
Not a big one, kind of a church.
Do you the difference between
a cemetery and a graveyard?
- They're spelled differently?
- Yes, it's a difference.
You don't know the real difference?
- [Sarah] No, I really
don't know the difference.
- I'm all proud of it
'cause I only learned it
like a week ago.
- Okay.
- Okay, so a graveyard
is attached to a church.
- Oh, okay.
- A cemetery
is wherever the hell it is.
And so it's the yard, it's
the yard of the church.
- Yeah, yeah.
- Yeah, yeah.
So I passed this cemetery.
It might have been a graveyard.
I didn't remember if there
was a church near it,
and I said, it was kinda twilight.
I say, (gasps) "I've seen this before."
But I know I'd never been
on that, so I had a deja vu.
And then the bus driver
said, and we just passed
the cemetery that was the backdrop
in Michael Jackson's the Thriller.
- Oh!
- There you go, there you go.
- There you go, and the weirdest thing is,
we've had this conversation before, Neil.
- (laughs) We gotta take a quick break
before we come back to cosmic queries,
potpourri edition on StarTalk.
(warm instrumental music)
(warm instrumental music)
We're back on StarTalk
potpourri cosmic queries, yes.
- Yeah, we are.
- Sarah, it's our first time together.
- Yes, it is, how am I
doing so far, I'm okay?
- Like 12 people observing to make sure,
'cause Chuck is normally
sitting right there.
- I know.
- And the queries,
people are phonetically
spelling their name
to help Chuck along.
- Yeah.
- And you're up there reading
the names for him, okay.
- I'm doing my best, I'm doing
my best impression of Chuck.
Actually, it's very subtle.
- There you go.
So collected from the
internet, just a grab bag.
- Yeah.
- If I don't know the answer
I'll just tell you, okay.
- Yeah, it's loudly
and confidently, all right, this one's
actually my favorite question.
- Really?
- Yeah, I'm just gonna throw it out there
from Brandon Bagley on Facebook.
What would be a more accurate
name for the big bang?
- There is no more accurate
name, the big bang.
- Oh jeez, wow.
- And what many people
don't know is that there's
a great astrophysicist,
Sir Fred Hoyle, who was
not a fan of the big bang
back when there was
enough slop in the data
to not have to vote
strongly one way or another.
He was convinced that the
universe was in a steady state.
He knew the universe was expanding,
so how do you have an expanding universe
that's also in a steady state?
You would have the universe
spontaneously create atoms
out of the vacuum and then
they would make new galaxies
and they would mix in
with the old galaxies.
So statistically the universe
just looks the same forever.
It's been expanding
forever and it gets rid
of the origins problem.
Then the idea of a big bang arose.
This was consistent with
Einstein's general theory
of relativity, and then Georges Lemaitre,
who was a Belgian priest
and mathematician,
he figured out if you turn
the equations backwards
all the universe would have
been in one place at one time.
Then there's a guy named George Gamow
who calculated what that should look like,
and there'd be a residue
left over from this moment
and it would be this
background in microwaves.
And so all this got laid out.
And Fred Hoyle wasn't having any of it.
And he pejoratively referenced
this idea as the big bang.
He was making fun of it.
- Right, but it stuck.
- It stuck.
- It stuck.
- And we are loving it.
- That's like when
you get a nickname to stick, like you just
you sort of appropriate it.
- Yep, yep.
- And you kind of use--
- And then they can't use it
against you.
- Yeah, exactly.
- Right, right, right, and
so there was the thought
that there was enough
gravity to halt the expansion
and have it repeat.
That had philosophical
attraction to people because
it meant the universe didn't
have to have a beginning.
- Right.
- In total.
We're just on a cycle,
and who knows what cycle.
Maybe it's been going on forever.
- Yeah, rinse, perm press.
- That's right.
This concept of a
beginning, somehow people
either really want it or
they really don't want it.
- Yeah, yeah.
- Right?
There's a bifurcation
of attitude towards it.
- Yeah, it's like a Rorschach test.
- It is.
- Of what people want to see.
- It is, and you know what my wife told me
before she was my wife, but
she has a degree in physics.
- And somehow still
managed to be your wife
after this comment, yeah.
- No no, she said she wondered
whether there was a split
between men and women
about the steady state
universe and a cyclic universe.
Men don't have the cycles that woman do.
- Oh, that's interesting.
- Yeah, so just,
what is your philosophical
leaning towards an idea,
and if that philosophy emanates
from the life that you lead
and know and resonate with,
you could have this split
between men and women, and
so she hypothesized that.
- So then guys say,
like, oh, so the universe
is super big, it's like
really impressively big.
Trust me, there's no problem there.
- No, the universe is stable.
- (laughs) Yeah, Fred Hoyle
I actually looked him up.
- He wanted the steady universe,
not the cyclic universe.
- He wanted to go steady.
- Go steady, ooh, very good.
- He has a pretty good quote about it.
He says that words like harpoons stick
and are hard to pull out.
- Mm, mm, good.
- I like that, I actually
think in answer to Brandon's--
- That's a very whaler comment.
- Part time, it was that
he dabbled in whaling.
He was a, obvious--
- Who, Fred Hoyle?
- No.
- Oh, you're making this up.
- Nobody dabbles in whaling.
I'm glad that I could
get you on that, though.
- Yeah, I haul whales
as a hobby on the side.
- Yeah, just part time, yeah, exactly.
- A part-time whaler.
- Yeah.
- So once he said it
pejoratively it stuck,
then he had nothing on us at that point.
And then there were observation
confirming the prediction.
Nobel Prize was given,
but he went to his grave
pretty much still a denier of--
- Of the big bang.
- Of the big bang,
so getting back to my
point, if the question was,
what better word, term
would I have for it?
There are people who, if the
universe would re-collapse
and then start as a bang
again, they call that
the big crunch, I don't know
why they wanted to say crunch.
If you look up that phrase, it's there
'cause gas clouds and
stars, they don't go crunch.
- Right.
- Potato chips crunch.
Crunchy things crunch.
- Yeah.
- The universe is not crunchy, right?
So I just thought it
was not the big crunch,
it'd be the big squeeze.
- Huh.
What about just, the really
big bang to convey this.
I mean, it seems to me like it's also,
even if it were the big bang proper,
it's not exactly an explosion.
- Well, we accept that
the signature looks like
if you exploded a grenade, for example,
or how about the chrysanthemum fireworks.
You know that one.
- Mm-hmm, yeah, yeah, yeah.
- All right, well some of
them, they are volume filling,
right, and so the outer
edge, well how did it get out
that far and reveal
itself at the same time
something that only went
halfway far out, right?
It must have been going twice as fast.
'Cause they both sort of
explode at the same moment,
but one is twice as far away as the other.
It was moving twice as fast.
That's an explosion that started this.
So it's not completely wrong
to think of it as an
explosion except that,
when we think of explosions
we think of an explosion
in the pre-existing space.
- In space, right, exactly.
- Whereas this is the
explosion of space and time
and matter and energy itself.
So it's of a very different nature,
but you get a little bit of
the ways of insight into it
if you think about it as an explosion.
Then you say, okay, I'm done with that.
What more is it to me?
And then you learn that
it's the expansion of space
and then you move on to deeper ideas.
- Yeah, I mean, well now the big problem
with the term the big bang is
there's trademark encroachment
from the TV show.
- Oh, yeah.
So I don't know if you knew this,
if you Google The Big Bang Theory
the TV show comes up before
the creation of the universe.
- The universe should sue.
- For me, I'm thinking,
am I happy about this or sad about it?
Is it good that people are watching a show
that's got scientists?
So my personal jury is still out on that.
I don't know if that's
good or bad, it just is.
- We'll take it up with the show later.
- Yeah, yeah.
- All right, hey,
this comes from Grady
Butler IV on Facebook.
- He's got a Roman numeral.
- Right, oh, does he.
Yeah, he absolutely does,
so we don't mess around.
- Chicks dig the Roman numerals, I'm told.
- Oh, do they?
- I don't know. (laughs)
- Neil deGrasse Tyson IV. (laughs)
- I have no Roman numerals behind my name.
Why are they Roman numerals?
Why don't you use Arabic numerals?
That's just not as cool?
- Well yeah.
Or you could just do
irrational number numerals.
- Yes.
- To the pi.
- Neil deGrasse Tyson the pi.
- Yeah, you have a son.
Why didn't you do like, Neil
deGrasse Tyson e or something?
- Yeah, yeah, no, 'cause
that's not how I roll.
- That's not how you roll?
- My name does not manifest
in either of my two children.
- Yeah, I've never understood
the desire to be like,
mm, that's gonna be me.
Property of Sarah.
- Right.
I just, that's not what I do.
- Yeah, okay,
that's good enough for
me, but Grady Butler IV,
after we've hated on his
name, from Facebook says,
hey Dr. Tyson, so I've heard a lot about--
- We're not hating on his name.
We were--
- Considering it.
- Celebrating his name, wondering
whether the day will come
where they'll use Arabic numbers.
- All right, I'm gonna
get to this question
before this guy produces an offspring.
Okay, hey Dr. Tyson, so I've heard
a lot about cosmic microwave
background radiation,
what we were just talking about.
A lot of physicists mention it,
but don't really explain it,
so what exactly is it?
- Oh yeah,
it's a great question.
So in the early universe
it was really, really hot.
So hot that the atoms were all ionized.
So they lose their electrons,
so then you have this soup
of negatively charged electrons
and atoms that want the electron
but can't hold onto them
'cause the soup of energy is so high.
It turns out that electrons
wreak havoc on light.
If you're a light beam and you try to get
through a crowd of electrons,
you're getting through.
The electrons see you, will
scatter you to and fro.
- So they're like bouncers.
- They're bouncers.
- Okay.
- They will push you,
scatter you, reverse you, so
there are no free sight lines
through ionized gas,
there's no free sight lines
through plasma, that's
why the sun is opaque.
It's just gas.
- Yeah.
- You could punch four fist through it.
Nothing's going to stop you.
You'd be vaporized, but holding
that complication aside.
- Right, minor setback.
- There's no surface there
for you to touch down on,
it is a glowing plasma.
And I had a tweet in reference to that
with my end of the Sun tweet.
When was that, back in March.
And I forgot the whole
tweet, something like
in five billion years when
the Sun dies it will expand.
Its plasma surface will
expand and engulf the orbit
of Mercury and Venus, it will render Earth
a burnt cinder before it vaporizes us
as we go up in a puff of smoke
into the vacuum of space.
- Have a nice day. (laughs)
- Have a nice day.
But that was the tweet, the point is,
I'm referring to the Sun as plasma.
The early universe was once all plasma.
Okay, at the temperature that the Sun was.
So what happens is as we expand we cool.
Oh, now there's not so much
energy to ionize the atoms
and all the electrons find an atom,
clearing the deck for
light to transmit freely.
Now the free electrons are no longer there
to bat to and fro the light
that wants to pass through.
So we now make complete
atoms and light emerges
at 3,000 degrees.
- So before there was
a plasma state of matter, but no light.
- No this plasma, sorry, it's glowing
just the way the Sun is, it's light.
- Right.
- Oh there's definitely light.
- Could anyone, like if--
- Yes.
You just can't see through it.
- I see, okay.
- You'll see it,
you just don't see through it.
- I see, okay.
- Now watch, it expands
and cools, electrons join, the
universe become transparent.
The universe expands by a factor of 1,000.
And it turns out the amount you expand
is a factor in how much colder it is.
If it was 3,000 degrees in that moment,
what's 1/1000 that temperature?
- Of 3,000?
- Yeah.
- Three.
- Three.
Right now the universe is three degrees.
- Got it. (laughs)
- How'd you do in your math class?
So what color light is three degree light,
because 3,000 degree light
is like reddish ember.
That light has now redshifted to today.
That temperature went from
3,000 degrees to three degrees
because it got diluted
from this expansion.
What color is three degree light?
Microwaves.
- Wow.
- Period, period.
We are bathed in the microwave remnants
of the formation of the universe.
- The cooling of the universe.
- Cooling of the universe.
Now if you go back in time,
there won't be microwaves.
Those would be red, and then
right on up to white and--
- Ultraviolet, is it?
- Some ultraviolet in it,
but it was not that hot.
You get ultraviolet, 20,000
degrees, 30,000, 50,000.
This was much cooler than that.
I'm just saying that we see microwaves
because of how late we are in the universe
relative to the formation of this.
And we call it the cosmic
microwave background.
- Which to me sounds like something,
like somebody with munchies
in college is looking
at a cosmic microwave.
- I don't know if you all,
when did you graduate college?
- 2014.
- 20, it's like yesterday.
- I mean--
- It's yesterday.
- 1914, 1914.
- Let me pinch your cheek.
- Oh.
- Oh, yes, yes, so, so,
in the day when you had
to get up off your ass
to change the TV channel,
if you put the TV channel
between two channels, this
is before remote controls.
- What happened?
(laughs)
Universe collapse, God, what happened?
- Collapse of the spice-time continuum.
- How did we not destroy the world?
- So you don't get clean
signals that are broadcast
'cause it's information
coming through an antenna.
And so what you have
is what we call static.
- Right.
- It's snow.
- Yeah.
- That's on the screen.
Some percent of that snow is the cosmic
microwave background.
- Wow, oh my God.
- A few percent of it.
- That's--
- You're measuring it,
yeah, it's everywhere.
- That's intense, and so
now that we don't have TVs
we have to change the channel,
it doesn't exist anymore.
You can't deal.
- It no longer works, right.
- (laughs) Should I leave?
- Right, right, right.
- Boy, that's awesome, okay, all right.
We have time for a very short question
before we go to break.
This one comes from Antonio Montoya.
I don't think that's your real name.
- Antonio Montoya.
- From Facebook says,
how far must I travel to see the backside
or the reverse view of the Big Dipper?
- Ooh.
- Yeah, interesting, right?
- Ooh, you know, I forget how
far away the Big Dipper is.
I just forgot.
- Hmm, just say something
confidently.
- But I can tell you this,
that the Big Dipper's stars
are not sort of in a line.
- Yes.
- And if they were in a line
you could go to the other side
and then see the big dipper in reverse,
but if they're not in a
line you can't do that.
So I've done this exercise
with all the constellations.
None of them look like--
- You got a lot of free time, Neil.
- (laughs) Me and the
universe go way back.
So you go to the other side
of these constellations,
they look nothing like what
they would do from this side.
- Yeah.
- As they would
form the other side, from above or below.
- It wouldn't just be reverse.
- Yeah, it's not just reverse.
Here's something you do, I did
this with a class, it's fun.
Get a long room that
can go completely dark.
Give seven people pen lights
or their smartphone will work
and orient them in the
shape of the Big Dipper.
Bring some really close
and some father away
and then have them turn on their lights
and you turn off the
main lights of the room.
Stand at the end of the room.
You have no sense of the distance to them
because you can't see them.
- Right, just the brightness.
- Just the brightness,
that's all you can see.
And you see a perfect Big Dipper,
but as you start moving closer to them,
the Big Dipper's completely gone.
So there's nothing real
about these constellations.
Contrary to what millions
of people in the world think
who get their instructions
for their day's life from the stars.
So take a quick break, our
last break before we get
to the third and final
segment of cosmic queries.
- Exciting conclusion.
- Potpourri,
and Sarah will be right back.
(warm instrumental music)
(warm instrumental music)
We're back, StarTalk.
I'm Neil deGrasse Tyson.
We are in the potpourri
edition of StarTalk.
Sarah, keep it coming.
- Okay, all right.
So the first one comes from Lynn Hughes
in Fall City, Washington.
She says, I get discouraged by
all the anti-science rhetoric
these days, how do you stay so positive?
What do people ask that gives you hope?
And what responses are most helpful
when talking to science skeptics?
- Mm, there's no such
thing as a science skeptic.
- Just a dumb-ass. (laughs)
- It's like saying (laughs)
I'm a gravity skeptic.
- Yeah, yeah.
- Yeah, I'm a skeptic that the Sun exists.
No, there's no such thing
as the science skeptic.
- You are a science skeptic
skeptic, is what you are.
- Yes.
- Okay.
- So what do I do, why do I stay positive?
It's because everyone
likes beating politicians
over the head, and they
simply bring forth,
in an ideal case and in
most cases they bring forth
the wishes of their electorate.
So if you're beating a
politician on the head
you're really attacking the electorate.
As an educator for me the
target of my affection
and interest will always be the people
and not the politicians that they elect.
- It's like getting mad at a scale
instead of getting mad at your weight.
- Exactly, I would
repeal the law of gravity
'cause I gained three pounds last week.
- Right.
- Not how it works.
So I think of myself as an
educator in that context.
And to equip the general
public with the methods
and the tools to analyze the
moving frontier of science
to process information about,
what is the state of science in the world,
and what is science and
how and why it works.
And hope springs eternal.
My favorite quote of them all is that,
and this too shall pass. (chuckles)
- That's pretty good, how did that go over
with your kids when you knew
they were being grounded?
- Right, right, so yeah, the anti-science,
it'll come back and bite
everyone in the ass.
And I say look, if you don't like science,
here are the consequences.
You will die sick and hungry and poor.
- But just that.
- Just that, that's it.
Innovations, I say this a zillion times,
innovations in science and technology
are the engines of tomorrow's economy.
And not only that, it will
assure a continued access
to your health, your
wealth, and your security
without which just move back
into the cave and throw rocks
'cause that's where you belong
if you were always a person in denial.
- I think to the question, she asked
about how you stay so positive.
I know for one thing,
you have a great sense of humor about it.
Like, some people--
- Oh, okay, see,
no, I don't have a sense of humor.
I don't think of it, okay, I think of it
just that the universe I hilarious.
- Oh, 100%.
- And I'm reveling this
to whoever will listen,
'cause I'm not actually
telling a joke, right?
- Yeah.
- Have a I told a joke?
No, but the universe is
funny, and I found it
that people learn more
when they're laughing,
or at least when they're
smiling as a minimum.
So why not celebrate the
hilarity of the universe
in ways that empower
people to learn evermore?
- And go to comedy shows with comedians
'cause they'll learn about
the universe that way.
- Love me some comedians.
- Yeah, okay so moving on,
sort of in the same vein,
cihunter on Instagram asks,
why do flat-earthers still exist?
Question mark, exclamation
point, question mark,
exclamation point?
- Yeah, so flat-earthers,
I've analyzed this problem.
- Yes.
- And I've concluded that the
existence of flat-earthers
is the manifestation, the
simultaneous manifestation
of two facts, one, we live in
a country, the United States
that protects free speech.
Two, we live in a country,
the failed educational system.
- Combine those two.
- Combine those two,
you have flat-earthers.
- The flat-earther hypothesis
for the existence of flat-earthers.
I kind of love that
applying science to them.
They exist in an unstable state of age.
- It appears to be stable, but I'm not,
so I say, go head,
think the Earth is flat.
I'm not gonna stop you,
it's a free country.
Or at least we tell ourselves
that, it's a free country,
but you should not look for
a job to head NASA, right?
Certain job categories
you should stay clear of.
And its, you know,
not only for those, there's
folks who are afraid
on the number 13.
- Oh yeah.
- Right, like--
- There are elevators
that don't go to the 13th floor.
- More than 1/2 of elevators
have no 13th floor.
I studied this.
- Oh my gosh.
- Along Broadway in Manhattan.
You can't go to every
building, but Broadway
has plenty of tall buildings.
It's a statistic, it's about 1/2.
- So is that floor empty, or
is it just the 14th floor?
- So for some buildings it
goes from the 12th floor
to the 14th floor.
- Yeah.
- For some buildings, for other buildings
they put all the
mechanicals on that floor.
- Oh my gosh.
- So it's still a floor.
- Yeah.
- It's still a floor but
they hide it, now what
were we talking about?
- Flat-earthers.
- Flat-earthers.
- They still exist.
- Thank you, yeah.
So free speech, go right ahead.
- (laughs) You look
exhausted by this topic.
- No, no, no, it's, I'm
not gonna fight you.
If you wanna think about it, go ahead.
- You know, you're--
- It's just, you know,
there are plenty of jobs for you.
If you're superstitious about
the number 13 or you want,
plenty of jobs for you, go right ahead,
but let's hope the people who are hiring
also know how that should go down.
'Cause if they don't, that's
the beginning of the end
of an informed democracy.
- I think that there's a lot
to why people think the Earth is flat
because it seems to be this
comforting conspiracy theory
that scientists are trying
to cover up knowledge
that we don't know yet.
- It's just odd that anyone
would think that
scientists would be leaders
in covering up knowledge.
That we somehow would be conspiring,
that somehow we're all conspiring
to make the world look
like it's getting hotter.
- (laughs) Right.
- You might say, well why?
- Personal advantage.
- Exactly.
What could possibly motivate
us as a diverse community
of scientists, and
I don't know, so I'm
too tired, I'm too old.
I can't chase people.
- I wish that these mics
were droppable, unfortunately they're
in a steady state condition.
Okay, let's see, here's
a very interesting one
I've never considered before.
Mr. Nate Kapp on Instagram asks,
could there be a universe
inside a black hole?
- Yes.
- Oh, wow.
- Yeah, next question.
- Next question, lightning
round, okay, we can go on.
- No, so the equations of space-time
as you follow them
across the event horizon
toward the singularity
allow an entire new universe
to open out in front of it.
- Wow.
- So as you fall into a black hole
your time ticks slower and slower and...
- It's a great anti-aging technique.
- Yes, well, yes, it is.
- Exfoliating.
- Yeah, I don't know about
the exfoliating, we'll see.
So you do this and time changes for you.
So as time changes for you, you will see
the entire future history of the universe
unfold before your very eyes
as the new space-time
opens in front of you.
- It's very hard to remain
funny and have jokes
when you constantly blow my mind, Neil.
So are you tempted, then,
to go into a black hole
because you could see--
- If I had to die, yeah.
Oh yeah.
- That's how you would go?
- Oh yeah, better than
getting hit by a bus
or drying of cancer or something.
- Oh, absolutely.
- Oh yeah, I'll die
falling into a black hole.
- Yeah, right,
spaghettification.
- Yeah.
- So there very well could be universes
inside black holes?
- Yes.
- That is very--
- Whole universes, right.
- All right, okay, so moving
on to our next question.
Oh, I like this one.
Roger Rachuba on Facebook asks,
does E equals MC squared,
does that equation
work with dark matter and dark energy?
- As far as we know, we have
no reason to think it wouldn't.
So whatever it is that's
causing the dark energy,
if it one day shows itself to have mass,
it's gonna join the rest
of all the mass out there
as a constituent, now dark
energy we don't know what that is
if it has mass, we don't know.
So but yeah, E equals MC
squared is fundamental.
In fact, it's true for
everything, everything.
I'll give you an example,
if you take a spring
and dissolve it in acid,
okay, and then measure
the temperature of the
acid you'll get some value.
If you take a spring, compress it first,
pumping energy into it
and put that in the acid
and dissolve the acid, the
temperature of that acid
is higher than the temperature of the acid
that you dissolved the unsprung spring.
- Huh, okay, so it takes the energy.
- Right.
- The potential energy.
- Right, so you,
so E equals MC squared, that E and that M
work not matter what.
- Wow.
- It is completely
fundamental to all phenomena
in the universe.
- Huh, yeah, it's interesting.
I tend to view dark matter and dark energy
as sort of like normal matter and energy
but with like an evil goatee.
- Yeah, yeah, okay.
- Sort of evil twin
cousin, and then I imagine
E equals MC squared was sort of--
- Why are goatees evil?
- I don't know.
- Maybe early illustrations of the devil
maybe had goatee.
- I don't know.
Somehow it got the branding
of the goatee went downhill.
It was some guy maybe who started it.
The mustache I feel like
is making a comeback,
so you're in luck.
(Neil chuckles)
You have a mustache soul patch situation.
- Yeah, yeah, yeah, soul patch.
- Is that--
- Mustache, I never shaved
the upper half of my mustache in my life.
- The upper--
- It doesn't grow, yeah.
- Oh yeah, it's kinda
hovering around the lip.
- Yeah, I'd say lower
half of the upper lip.
- Yeah.
- Yeah.
- So, I always figured
that E equals MC squared
would have some sort
of inverse relationship
with dark matter, dark energy.
- No, just if it's matter
at all or energy at all it
can fit into that equation
and convert to the other.
- Wow okay, even it it's dark.
- No matter what, oh yeah.
- But it's just more evil.
- (laughs) It's dark.
- Give me that.
- Evil energy, yeah.
- Okay, all right, let's see.
My next question, and I think
probably our final question
for--
- We have time
for more one more question.
- Yes, okay, so this--
- We never did the lightning round, yeah.
- We didn't do a lightning round.
Oh well, okay, so our last one comes
from King J. Mattheus on Instagram.
What are your thoughts--
- King?
- Yeah, apparently it's a
king, so thank you, your honor,
your highness for reaching out
to us on Instagram. (laughs)
- What?
- Probably Instagram
I'm guessing or his mom's basement.
All right, so King J.
Mattheus on Instagram asks,
what are your thoughts on China
planning to get rid of all
the space junk with lasers?
- Ooh.
- You hear about this?
- Yeah, so space junk is bad.
- Yeah.
- I think we haven't
been visited by aliens
'cause they saw the space
junk and said, forget that.
Y'all just--
- Messy.
I don't want to deal with that.
- Right, right, right, put my ship at risk
'cause your garbage.
- Yeah.
- And so a couple things
you can do with lasers.
You can vaporize the target.
You can accelerate it out of orbit.
- Right, put it on a different planet.
- Yeah, but you can do multiple things,
but I will say that
that's a big cleanup job
because it's not like a
spilled thing on the floor
in your kitchen, it's scattered
all over the solar system.
And then you hope it doesn't
come around to kill you again.
- Right.
- Ideally, we would vacuum
it all up and send it into the Sun
where it will vaporize
or bury it or something.
- That somehow feels like a cop out.
It somehow feels like, you know,
we should just be having
less junk junk out there.
- We should have a handle on our own junk.
- Yeah.
- Don't pass the buck
to the Sun.
- That's the sort of cosmic
sweep it under the rugs.
- In one of the most famous
books ever written on gravity,
it's called "Gravity."
- I would say, I don't
know what I was expecting.
- Right, right, right, it's gravitation.
They talk about a black hole
and how you could use it
to cycle garbage.
- Wait a second,
we see a black hole, this
like giant cosmic phenomenon.
- Beautiful cosmic phenomenon.
- Great place
to put our garbage.
- Right.
In case Earth gets too
filled up with garbage,
non-biodegradable garbage,
just toss it into a black hole.
So Sarah, we gotta call it.
- I think we do.
- Yeah, thank you, it's your first time!
- And I survived, I'm still alive.
- First time.
- Was it good for you?
It was good for me.
- It was okay for me.
- (laughs) I'll take it, I'll take it.
- Yeah, we need upside potential there.
You have been watching and
possibly more likely listening
to StarTalk, it's the comic
queries potpourri edition.
Sarah, thanks for being on the show.
- Thank you for having me.
- I am Neil deGrasse Tyson,
your personal astrophysicist,
and as always I bid you
to keep looking up.
- To keep looking up.
- Very nice.
(Sarah laughs)
(warm electronic music)
