You’ll hear why a black hole’s consumption of matter does not overpower the evaporation caused by Hawking radiation. Neil tells us what’s actually “evaporating” during Hawking radiation. He also tells us two remarkable facts about black holes that are sure to blow your mind.
We discuss how a spy satellite accidently opened a new branch of astrophysics. Find out more about singularities. We investigate the singularity at the beginning of our universe and Neil explains when string theory needs to be brought to the table. Chuck shares how his son coined the word “ringularity.” We assess the possibility of black holes being used as an intergalactic highway system to connect one galaxy to the next.
Find out more about “white holes.” Discover more about supermassive black holes. We explore the nature of photons: how they can be pulled into black holes if they’re massless and why they travel along the fabric of spacetime. Adventure back in time to Sir Arthur Eddington’s expedition to uncover how light bends around the sun.
We ponder if dark energy and dark matter are “stuff” permeating from another universe into our own. Discover why light is trapped in our galaxy but gravity isn’t. We discuss the likelihood that intelligent life is more advanced than us. Lastly, Neil shares final thoughts on the delicate evolution of the tree of life.
Thanks to our Patrons Ricky Saull, Nisarg Joshi, Brett Witan, Paul Fullop, Ari Moudi for supporting us this week.
NOTE: StarTalk+ Patrons and All-Access subscribers can watch or listen to this entire episode commercial-free.
Transcript
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Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk. I'm Neil deGrasse Tyson, your personal astrophysicist, and I'm with Chuck Nice, co-host. That's right. Chuck and we are...
Welcome to StarTalk, your place in the universe where science and pop culture collide.
StarTalk begins right now.
This is StarTalk.
I'm Neil deGrasse Tyson, your personal astrophysicist, and I'm with Chuck Nice, co-host.
That's right.
Chuck and we are recording live from my office at the Hayden Planetarium of the American Museum of Natural History right here in New York City.
Better known as the Cosmic Crib.
Oh, the crib.
Welcome to the crib.
That was high currency when I was in college.
I haven't heard anybody use it anymore.
No.
Yeah.
Nah.
It's kind of a...
It's just very dated.
It's very dated.
Yeah, yeah.
But it still sounds cool, the crib.
It does.
Yo, what's up, man?
I'm just chilling in my crib.
See, that works.
That still works.
For anybody over 50.
So this is actually part two of Cosmic Queries we began last time.
That's right.
Because we had sufficient questions to populate two Cosmic Queries on black holes and dark energy.
People love it.
I know.
People want to know a lot about the dark energy and black holes.
And since we don't know anything about dark energy, I want to know about it too.
That's right.
All right.
Give it to me.
What do you have?
All right.
So we are going to start with a Patreon patron.
As is our habit.
Absolutely.
So this is Chris Hampton and he says, Hey, Hawking Radiation states that a black hole will eventually evaporate completely because it's releasing small amounts of energy slash mass over time.
But wouldn't the black holes consumption of matter overpower the radiation, making the black hole grow instead of evaporate?
Yeah, good.
So if you have an isolated black hole, it's not consuming matter.
Right.
It's nobody there to eat.
Exactly.
You have to come embarrassingly too close to it for it to tidily distress you and capture you.
And now they're not.
Right.
And you have to be moving not too fast, otherwise you'll just whiz by.
Right.
So the black holes are not some voracious vacuum cleaner that sucks up everything it sees.
I'm so hungry.
Right.
That's a tiny black hole.
That's a little black hole.
I'm so hungry.
And the big black hole.
I'm so hungry.
Right.
The super massive black holes are like, feed me.
And it's funny, this voice frequency thing.
You never have a high frequency voice selling a truck.
Right.
That's true.
Which now I want to see Mike Tyson actually sell Dodge Rams.
Just like, you know, that's right.
It's Ram tough.
Dodge Ram.
Okay.
Because he is a tough guy.
He is a tough guy.
The question whether that will compensate for the voice.
Exactly.
Plus, you know, the voice of God is never high-pitched.
No.
It's never just like, Hey, guys.
I think I'm going to smote you today.
Now I wish Michael Jackson was alive to be the voice of God.
You know, just like, You're very ignorant.
You're very ignorant.
I don't like that.
Stop it.
Exactly.
I'll send a tsunami.
So, this information that it consumes, if it's by itself, By itself, it'll just evaporate.
Yes.
Clearly, and as correctly surmised, if it has a food source, Right.
It's just going to eat and the Hawking radiation will be insignificant of a loss relative to what it's eating.
Gotcha.
But eventually, all black holes will have eaten anything they can eat Right.
In their refrigerator.
At that point, then it will slowly start evaporating.
At a higher rate than it was gaining mass.
Gotcha.
So that's how that plays out.
And the evaporation, though, if nothing can escape, what is actually evaporating?
Good question.
Very nice.
Evaporation is, we're using the term loosely here.
All right.
So what's actually happening, and it's brilliant.
It's just, it's beautiful.
Okay.
I have to say, it's beautiful.
It's beautiful.
It's beautiful.
So what's going on is the gravitational field in the vicinity of a black hole Okay.
is so intense, right, that it will spontaneously create matter.
Holy crap.
So the energy density, because E equals MC squared, if I have matter, I can turn it into energy.
That's what nuclear bombs do.
But if I have energy, I can turn it into matter.
Right.
The energy density in the field of black holes is so intense, right outside the event horizon, outside the event horizon, it will create particles.
Wow.
Out of the gravitational energy density of the field.
Now watch.
Here's the spooky part.
These particles were not inside the event horizon.
They're created outside the event horizon.
Right.
Now watch what happens.
When anytime you make particles from energy, you make two particles every time.
Okay.
Matter and antimatter pair.
I don't know if you knew that.
Okay.
And they will travel in the exact opposite directions from each other.
That means one escapes, the other goes right back on in.
Right.
So, but the one that escapes, escapes forever.
Right.
If you measure the mass of the black hole, it is now less by the mass of that one particle that escaped, even though these particles were created in the gravity field of the black hole itself.
Nice.
So it's giving of itself just from the energy density of the gravitational field.
It's really a remarkable fact.
That is remarkable.
Right.
Yes.
And so Hawking figured this out.
And then concluded if this keeps up, the whole black hole is gone.
Right.
At some point.
Right.
That's amazing.
So it's...
And in fact, the smaller the black hole, the faster it will radiate.
It's a surface area thing.
Here we go.
Surface area alert.
Because we have a whole show on surface area.
So the larger the object, let's say it's a sphere, the larger the object, the less surface area it has relative to the volume.
Right.
And the smaller you are, the more is your surface area relative to your volume.
This is why children and babies should not spend too long in the hot tub.
Right.
Because their connection to the hot environment is way more devastating to their body than it is if you're bigger.
Right.
That's all.
So, as the black hole gets smaller and smaller, the rate of evaporation increases.
Because its surface area gets larger and larger compared to the volume that's inside of it.
The surface area of the event horizon.
And the intensity of the energy goes up.
And so its very last gasp is a pulse of light of the highest known energy, which are gamma rays.
Wow.
That's pretty cool.
So, the original paper written by Hawking talked about bursts of gamma rays in the universe.
From black holes evaporating in their very last gasp.
And then we saw gamma rays in the universe with a telescope after the data were declassified.
We had a telescope launched in the early 70s.
Trust but verify, right?
Oh, let's sign the test ban treaty.
No nuclear tests in the atmosphere.
Anywhere else we said, okay, Ruskies, but we're going to put up a satellite that will look for gamma rays just in case you don't fulfill the treaty.
And we started detecting gamma rays, like, every day.
I said, can we get some ground truth on this?
Checked other satellites, no explosions anywhere.
A whole brand new field of astrophysics was pried open by accident because we're trying to verify...
Because we don't trust the Russians.
Because we don't trust the Russians.
And I don't know why we wouldn't trust the Russians.
They're such good people.
I want to be friends with them.
Good people all around.
So, those gamma ray bursts, are they these black holes?
No, because you can look at the properties and it's not.
Fascinating.
Man, thank you.
Hey, Chris, thank you for that.
That was really a nice trip, man.
I love it.
Is it also Patreon?
Yes, I cut them down so they're easier for me to keep in order.
So this is your second Patreon question?
Yeah.
Okay, good.
Oh, no, no.
This is just regular questions.
Oh, no, this is Patreon.
Right here.
It's color-coded.
This one.
No, not that one.
Not that one.
There.
Okay.
Get that one.
Just pick it up.
All right.
Here we go.
Next Patreon question.
Go.
There we go.
This is from Oaksteel's funny fake one.
Okay, you're just screwing with me.
I know that now.
I don't think I have a proper question here.
I don't have a proper name either.
Chuck is making people feel good.
But can you tell me about the singularity of a black hole?
Whatever you know about it, thanks in advance.
There you go.
I'll tell you what we know.
At the center of a black hole is supposedly a singularity?
I'll tell you what we know.
The collapse of a thing to a black hole, we take it to a black hole because there's no known force to us in the universe that would prevent it.
And if you do the math, the gravity is so severe that it will collapse to get denser and denser and denser until it is infinitely small, which would make it infinitely dense.
Because density is mass divided by a volume, grams per cubic centimeter, pounds per cubic foot.
These are statements of density.
So if you have a certain amount of mass and the volume goes to zero, what happens if you divide by zero?
Well, you get an error on my calculator.
Okay, before you get to zero, the numbers get astronomically large.
So they actually get to infinity.
So it is infinitely dense.
And so can you even have that in nature is the question.
You don't know.
But invoking only Einstein's general theory of relativity, you get a point of infinite density.
Strength theorists came along and said, we got this.
It's not infinite density.
They're strings.
And there's another thing going on in the universe.
That's why you bring in strength theorists.
We ring the bell.
They come in and say, we got this.
You needed extra physics on top of general relativity to understand the singularity.
And once you did that, they say, hey, this is good to us.
Let's think about the singularity that began the universe itself.
The Big Bang singularity.
So this gives you access to previously mysterious elements taking Einstein's theories to their limits.
So if there's no singularity, there could be something else.
But according to Einstein, that's what you get.
Yeah.
But we're admitting that Einstein's theory is incomplete at the singularity.
We're waiting for a bigger theory to come along to replace it.
That's pretty fascinating stuff, man.
I just love it because, yeah, that makes sense.
It's like there's a single point.
And how do you even wrap your head around it?
Right.
Right.
Yeah.
That's pretty wild.
We're awaiting some new physics, or we got to successfully wrap our head around something infinitely small and infinitely dense.
See, I get the infinitely small, infinitely dense.
I mean, you know, I see...
That's at the center of the black hole.
And so if you...
Oh, if the black hole is rotating, then it's not a singularity.
It's a donut.
Ah, a ringularity.
A ringularity.
Oh, I like that word.
I learned it from my son.
I got to be honest.
He said ringularity?
Yes.
He came up with that word?
I don't think he came up with it, but that's what he told me it was.
That's a good word.
I said, it's a singularity.
And then he went to Jan 11, and she said, yes, it's a ringularity.
I was like, I hate you, boy.
Is this the one that wants to start an astrophysics club in his middle school?
Yes, in his middle school, yes.
And not a comedy club?
Thank you, Jesus.
Is that a burn?
I don't care.
I'm just happy that he does not want to go down this path.
This path?
Be an astrophysicist and write some books and take care of your father.
That's what I'm saying.
That you want him to do with you.
Okay.
But anyway, yeah.
Yeah, that's pretty cool.
This is messy.
I have a better idea.
For what?
The MyStrips.
You're taking all these papers.
You hold it.
I'll hold the papers.
I have a black bag here.
These are all my questions.
This is actually an actual black hole.
Because first it says it.
It says a bag.
I got all kinds of stuff in my office.
Oh, that's hilarious.
And as all black holes.
And as all black holes do, watch you as you fall in.
Oh, that's hilarious.
So this is my black hole bag.
It's a black hole bag.
It's got a drawstring.
So put them in here.
I'm putting on the bags.
And now I'll just pull them out.
Oh, now listen.
You get your question answered at random.
Okay, go on.
Okay, I'm going in.
Wait a minute.
I just fell in a black hole.
You know, I didn't experiment with what was inside of here.
You just did that experiment.
Exactly.
All right, here we go.
Chris Wakefield wants to know this.
Hi, it's Chris.
It's a philosophy question.
Since every galaxy we observe so far has had a supermassive black hole at the center of it, and theoretically a black hole could be turned into a wormhole, what if they were used as save points, like in a video game, across space and time for a creator of sorts to get across galaxies more quickly to create what we know as space?
I'm not sure what that is.
So, Chris, number one, please give me the number of your weed dealer.
That is the first thing I would like.
This is some good stuff.
So, anyway.
I think what he wants is, because black holes and wormholes are related and may be related, and he wants to know whether there's some...
I might be exaggerating his question.
There's some intergalactic highway system that connects one galaxy to another across the universe through these black holes.
In other words, it's kind of like...
What's that city?
Milwaukee.
No, no, no.
It's not Milwaukee.
You're talking about...
Minnesota.
Minnesota is the name of the state.
I'm saying, but it's in Minnesota.
Minneapolis.
Minneapolis.
That's what I'm trying to think of.
You never have to go outside.
I mean, when it's 40 below.
It's really cold.
And you just walk between buildings.
Right, right.
And there's Skyway News.
It's called Skyway.
I think it's called Skyway.
I think it is called Skyway.
And to me, the first time I saw it, it looked like an ant farm.
The human habit trail.
I felt uncomfortable in that.
I said, this is some...
We are in someone's zoo.
Protect the Queen!
Protect the Queen!
So, buildings are connected, so you never have to go outside.
Exactly.
And so, here's the thing.
I lived...
Nobody would live the idea more than I would.
Here's the thing.
If a black hole which only eats things is a portal to a wormhole, the other side of that wormhole can't also be a black hole.
Right.
It has to be shoving things out.
That's called a white hole.
Oh, really?
Yes.
Now, see what?
White hole gotta be given and a black hole gotta be taken.
That's what I'm trying to figure out.
Chuck, not every reference is bad to black things.
All right.
Okay.
All right.
Do we have a...
The black plague?
A kiss my black...
A kiss my black hole.
All right.
You just said you were born too late to join the Black Panthers.
Is there really a white hole?
That's a white hole.
Black Panthers, that's a double reference back.
The Black Panthers is the group from the Civil Rights Movement.
Not the movie.
That's right.
And the guy that uses vibranium.
So, where were we?
We were talking about the fact that there is something called a white hole.
Yes, so something called a white hole.
That you didn't just...
I did not totally make it up.
This was explored in the 1970s.
When the mathematics of black holes were coming to maturity, and someone posited, well, if you have a black hole, what's on the other side?
It would be like a white hole.
I mean, why not?
Where everything only comes out.
Then how would you connect them?
With a wormhole.
So, you get this three-for-one deal on that.
And then you can ask yourself what a white hole would look like in the universe.
So, in the 1970s, we said, if this is what a white hole would look like, let's check the data, let's go to the universe.
Nothing in the universe resembled it.
Not even quasars, which are intense emanations of light from the distant universe in a very small volume.
So, we abandoned that.
So, I don't mind wormholes connecting the galaxies, I just don't see how you would invoke the black hole to do that.
To do it.
All right.
Great question.
We're going to take a break before we get lost in the black hole bag.
And when we come back, more Cosmic Queries, black holes and dark energy will return.
We're back, StarTalk, Cosmic Queries, Black Hole, Dark Energy.
We had so many questions, it's part two.
This is part two.
And for this part, I have my special Black Hole bag.
Black Hole bag.
That's hilarious.
It's just a black hole.
That's right.
All right, and I don't know why they got little Google eyes on it, but okay.
So reach in.
And so I'm reaching in, the black hole, and okay, it just seems to be, wouldn't it be funny if my hand just came out of the top here?
Oh, that would be really freaky.
That'd be a wormhole, right?
The wormhole black hole bag.
All right, hey, this is Mike Rush from Facebook, and he says, if nothing can escape a black hole, including light, and nothing can move or travel faster than light, how is there a massive jets of X-rays coming off many super massive black holes?
Wouldn't that mean that these particles slash waves have been accelerated beyond the speed of light?
These people paying attention to the news.
These people reading this stuff.
These people are on top.
They're on top of this.
On the game.
Why are you ripping up the band, the boys question?
I was trying to make it for, like, you know, just emphasis and...
Emphasis, yeah, okay.
I was trying to, you know, be emphatic, but instead I tore his question.
You don't do that really well or belt?
Have you ever done that with a belt?
Of course, yes, snapping a belt.
Like this, I'm talking about.
That's how I keep my comfort in line.
No, but what's good?
I just take the belt and keep...
I have a belt, but it's not for con...
Oh, no, it's leather.
Is it a leather belt?
Give me, give me, give me.
I'll show you.
I just want to show you something.
Just leather?
Yeah, that'll work.
Okay, so watch.
There you go, all right.
For those of you listening, Neil now has my belt.
My pants are down around my ankles.
Neil has my belt.
This is just, I just want to show you, okay?
You see that?
Okay, so it turns out that sound is only made at the last instant that these make contact.
Okay, that makes sense.
Okay, but if you put your finger there.
No, I'm not doing that.
You do it, I promise, I promise.
What kind of trick is this?
We go way back.
I'm gonna trust you.
Here we go.
Well, just again.
I'm not leaving my finger in there.
You can now put your finger in.
Oh, come on now.
Oh, look at that.
Oh my God.
See that?
Look at that.
You didn't know about that?
I had no idea.
So you can scare people with it.
Right.
But really, it's just.
And nothing.
It doesn't.
That's amazing.
Cause it's only the-
It doesn't hurt.
You didn't know about that.
Yeah, but see, listen, I'm black.
That belt represents a lot.
A whole lot of butt-whooping.
That's right.
All right.
Oh my God.
I've never seen that.
I can't wait to go home and do this to my five-year-old.
Now put your finger in there.
That was awesome.
You can put your-
While I'm answering.
So the question was, oh, about the, okay.
So here-
So these supermass, these X-rays that are coming off of these supermassive black holes.
Here's what happens.
You have all this matter trying to get into the black hole.
Gotcha.
Not on purpose.
Right.
Trying to not get in the black hole.
Right.
All right.
Most matter that falls towards a black hole is not falling exactly online with its location in space.
That would be unusual.
Right.
Typically, it would just fall off to the side one direction or another.
Gotcha.
So it turns out, the system, the rotating system, as matter tries to come in, it'll miss the black hole, but then it'll get pulled into orbit around it.
Gotcha.
And so now you have this circulating matter.
And we have a term for it.
It's called an accretion disc.
An accretion disc.
It's accreting material.
All right.
As this accretion disc feeds the black hole, the innermost part of it goes unstable in its orbit, and then it spirals down, and that's lost forever.
Right.
Okay.
But, in order for all of this matter that used to be out here to end up here, there's a lot of gravitational energy it has to release to do that.
So, let me just a little more TMI on this.
You ready?
Good.
Go for it.
If I just drop something towards earth, what happens to its speed?
It increases.
It accelerates.
It accelerates.
Right.
Right?
All right.
9.8 centimeters per second squared, or some crap like that.
Meters per second squared.
So it's 980 meters per second.
That's funny.
Meters per second squared.
980 centimeters.
Right.
So here's the thing.
So to get from some distant place to the black hole, and then stop moving, where does all that energy go?
All right?
And what I'm saying is any matter that's trying to get to the black hole from far away is gonna have to release that energy if it's gonna land where the black hole is.
Right.
And so since most of it misses the black hole and goes to the side, you get this disc.
And so you have this disc of material all trying to get in and there's friction between the inner layers that rotate faster than the outer layers.
There's material hitting it and then again stopping because it hit it, but that's a collision with it.
And we have bright spots that show up on these accretion discs.
That's an active place.
Yeah, that's right.
And if you're a disc and you're trying to radiate, you can't radiate through the disc because there's disc stuff there.
Where's the only place that's free and clear to spit up material and energy?
Above and below the disc.
Right.
That's great.
So you have this thick accretion disc and it's basically empty on the top and bottom.
Right.
So all the energy that is trying to get in and can't will get released in the opposite directions.
And you get, generally, generally you get two discs coming out on the poles of this accretion disc.
That's beautiful.
You get two jets coming out at the poles of the accretion disc.
That's amazing.
Yeah, it is completely amazing.
And those are all the pictures that you see of the black hole with the jets spewing out.
With the jets coming out.
And this is material that never got into the event horizon.
Right.
So it's not that it's escaping the black hole.
It never made it in.
It never made it there in the first place.
It's actually the dejected, non-party going club people that were not allowed into the club.
Rejected from the velvet rope.
They couldn't get past the velvet rope.
They weren't just walk away.
They got ejected.
Exactly.
That is wild.
Yeah, so there it is.
And that's why.
So, but you only get it if you have an accretion disc.
Right.
And if the accretion disc is really thin and sparse, then the energy can go kind of in multiple directions.
You won't get these really strong jets.
Like strong plumes that come off the top of the bottle.
And what it also has a way of doing is, the term is collimates.
So it actually makes everything come out only in that one direction, like in a pencil beam.
Nice.
All right.
So if you don't happen to be in a sight line to it, it's not going to be very bright to you.
Exactly.
So there's some galaxies that are supremely bright.
And it's because we think that this jet is actually facing directly towards you.
With all this energy focused down into this jet.
That is amazing stuff.
What a great question.
There you go.
Nice.
Excellent.
Hang on.
Mix it up.
I'm going in.
Going in the black hole and I'm pulling out.
Here we go.
This is Kenoda Bradford.
Kenoda.
Once, oh no, I'm sorry, Kianta.
Kianta Bradford.
How can Kenoda become Kianta?
Because I just made it that.
Kianta wants to know this.
If photons have no mass, how does the gravitational force of the black hole pull in the photons?
What a great question.
Oh, I can answer that in two ways.
Each of them kind of mind-blowing.
All right, good.
Are you ready?
Yes, please.
Excellent.
So the first one is simple.
Right.
Energy and mass are the same.
There you go.
Two sides of the same coin.
You can plug the energy of the photon into E equals MC squared equation.
That's the E.
And divide that by C squared and out the other side comes the mass.
Right.
And the cool thing is, and that makes sense.
That's why you have an equal sign there.
That's what an equal sign is.
That's how equal signs roll.
When you're doing a calculation, E equals MC squared is the same as M equals E divided by C squared.
Exactly.
So C is the speed of light squared.
So you take your energy, the photon, divided by C squared, you get a mass out of that.
There you go.
So now you can think of the black hole attracting a mass.
And it'll attract it in exactly the way, it'll attract the photon exactly the way it would a mass of that amount.
Okay, but wait, that's not the more interesting answer.
Well, you had me.
A photon Okay.
along the fabric of space time at all times.
All right, give me a second, man.
Just wait a second, please.
Give me one second.
A photon travels travels along the fabric of space time.
Yes.
At all times.
Yes.
So therefore, Yes.
It is not traveling at any time, although it's traveling in time and space.
You went a little too far.
I went too far.
Okay.
Okay.
I'm not as artful at explaining this.
No, here we go.
So my brain is...
So here we go.
Go for it.
So here we go.
So holding aside the fact that because the photon goes at the speed of light, it has no time.
Let's hold that aside, because time has slowed down so much, it's actually stopped for a photon.
So photon has no time at all.
It has no inner clock.
So the instant it is emitted anywhere in the universe is the same instant as it is absorbed by your detector at the business end of your telescope.
To it.
To it.
To it.
It knows nothing of the journey between being formed and hitting something and getting absorbed.
By the way, I say about my photon, but if you're on the beach sunning yourself, there's a photon from across the galaxy, travel the whole galaxy and lands on your buttocks.
And that's how it ended its life.
Oh, that was a happy photon.
Senses, you got this.
So holding that aside.
Right.
You've heard of the famous experiment conducted by Sir Arthur Eddington.
Oh, of course.
My favorite.
Yes.
Sir Arthur's famous experiment.
Artie.
Yeah, old Artie.
So, four years after Einstein put forth his prediction that gravity bends space and time, Arthur Eddington, during a total solar eclipse, conducting an expedition.
I know this story.
That's why I knew you knew it.
To measure whether light coming by the edge of the sun, whether its path was bent.
And the way you do that is, you get a map of all the stars during a solar eclipse, because you can't see the stars otherwise.
And get their exact position on the sky.
Then wait six months later, and take a picture of that same part of the sky.
Six months the sun is not in the way.
There it is.
And then you compare their positions.
And he found that the stars closer to where the sun was, their position had shifted.
And so, this is the bending of starlight around the sun.
So cool.
Okay, so here's the point.
Go ahead.
The starlight never bent.
The light, the photons always took a straight line.
That straight line was bent in the fabric of space itself.
Which means.
The photon knew nothing else but to take that path.
Wow, so the actual curvature of space time itself is the surfing.
That's what, the photon is surfing.
The actual curvature of space time itself.
Yes.
Holy shit.
That is what.
My God.
Okay, so.
Oh my God, that's amazing.
So, in that context, the black hole isn't sucking in the photon.
The photon is just following the curve.
The photon is on a skateboard in a pool.
Yes, skateboard.
That's what's happening.
It's skateboarding.
It's on a skateboard in a pool, and it's just following the dip of the pool, man.
There you have it.
Dude, that is amazing.
Yes, photons do that.
That's awesome.
Yes.
Oh, that's so awesome.
Yes, so light technically never curves, because that is a straight line to it.
Wow.
Wow.
So in other words, let's say the path came around.
Right.
And you stand here.
Right.
It looks straight in this direction.
You're seeing this spot.
That's right.
Because space curves.
That's right, that's amazing.
That is so cool.
So as far as space and the photon is concerned, they're just going in a straight line.
Exactly, oh my God, that's so cool.
That is really great.
There you go.
That's good stuff right there, baby.
Listen, I don't even want to finish this show.
I'm good.
We got to take a break.
Coming up, yet another segment of Cosmic Query's Black Hole Dark Energy Edition on StarTalk.
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Thanks We're back, StarTalk, Cosmic Queries, Black Holes, I got to say it right, Black Holes.
Black Holes.
Black Holes and Dark Energy.
That's right.
I got to add something to my answer.
About?
But you were so...
Yeah, that was, it's good stuff.
Can you handle more?
I'm not sure, my head might explode.
It's great though, go ahead.
So, the experiment that showed that light bent coming around the sun in 1919, four years after Einstein had his idea in 1915, published in 1916.
So, you might see both of those dates, but referring to the same ideas.
So, he predicts that space will curve in the vicinity of strong gravity, or any gravity, but you want to be able to measure it.
So, you want a strong gravity source like the sun.
So, watch.
It turns out, if you plug the energy of the photon into equals MC squared and get a mass, and then predict what the curve would be, you get Newton's answer to that question.
You don't get Einstein's answer.
In fact, Newton, that's ordinary gravity.
It's a mass and a thing.
That would be the rubber sheet.
We're not yet at the rubber sheet yet.
Newton doesn't know anything about rubber sheets.
It's just, I'm a mass, you're a mass, we attract each other.
Right.
So, even though it would have never been measured before the curving of light, it had to curve by the amount predicted by Einstein.
Absolutely.
It can't have just been curved light.
So, you will see news accounts remembering this experiment.
They say, and the light bent around the sun proving Einstein.
No, that just proved that the photon responds to gravity.
Exactly.
I get you what you're saying now.
Right.
Yes.
So, when you invoke Einstein's full-blown general theory of relativity equations, you predict twice the deflection of the beam of light than a standard calculation with Isaac Newton.
And the measurements made by Sir Arthur, Ernie, Artie.
Our boy, Artie.
And his measurements recovered that full factor of two difference between what you would have measured.
So, the problem is no one had measured the curvature of light before.
So, it gets bundled together with what would have happened if the light curved but was not as big as Einstein's number.
Exactly.
It would have just been Newton, your light is also curving.
Right.
Exactly.
Because...
Newton didn't know anything about E equals MC squared.
Exactly.
So, yes.
So, now it's just like big object, okay, or mass attracts.
And so, now that's why you got the curve.
And you get the curve.
Right.
So, we wouldn't be cool with that.
We wouldn't be cool with that.
We would just be cool.
We would have curved because the gravity pulled it.
Exactly.
Whereas Einstein, in the fabric of space time, when you run the math on his equations, you get a factor of two greater than Newton.
Which...
Oh, my God.
Which is right.
Exactly.
So, that's amazing.
And that there shows you that it's the fabric of space time itself.
Rather than just gravity pulling on something.
I love science.
Are you ready?
Space tells matter how to move.
Right.
Matter tells space how to curve.
Nice.
That's a quote from John Archibald Wheeler, a student of Albert Einstein.
And I met my 2B wife in his relativity class.
Oh, sweet.
All right.
Let's move on.
Go to our black hole bag.
Into the black hole bag.
Pulling out.
All right.
Hey, Fernando Rodriguez wants to know this.
Is it possible that...
He could be from Hackensack.
It's just, you know, Fernando Rodriguez.
And then it says Fernando Rodriguez.
All right.
I like Fernando.
Fernando Rodriguez.
It's so very good to meet you.
What?
That's the Puss in Boots.
I was about to say, perhaps you know my friend Kitty Softbuzz.
Who was the actor?
That's Antonio Banderas.
Antonio Banderas.
That was one of the funniest characters of all of Shrek.
Okay, go on.
Okay, is it possible that dark energy and dark matter are stuff permeating into our universe from another nearby universe and that our matter and energy is being permeated into another universe?
Here's the caveat.
Via black holes.
So, I mean, just think about it.
Hold off on dark energy for a moment because that's just everywhere and it would not lend itself as well to this expectation as dark matter would.
So, dark matter is a source of gravity about which we know nothing.
It's not black holes.
It's just gravity out there.
We don't know what's causing it.
Maybe it's some new particle.
We've got top people looking for new particles.
Particles that don't interact with you in any kind of way, don't care about you.
So it could be just another sort of coexisting state of matter that we have to learn about.
All right.
Got you.
Did you know this?
I don't know if you knew.
That light is trapped within our universe.
It can't get out.
But gravity can.
That's wild.
Yes.
Isn't that interesting?
That is very interesting.
And I never took a full up field theory course in graduate school where I would have learned this.
So I'm describing this to you because this is what people who I trust and who are experts have told me.
Not because I did the...
Mostly the other stuff I talk about here.
I've done the calculations.
But the things I have, I just trust in them.
Okay.
The field theory course.
Right.
In it, the properties of gravity are such that it is not contained within our universe.
So if there's a parallel universe, it in principle could feel the effects of gravity in our universe.
Well, then so would the opposite be true.
Right.
So if that's the case, maybe there's a hunkering universe out there because 85% of the gravity of our universe comes from what we call dark matter.
Right.
85%.
Wow.
So we are just blips on a...
We're froth on the waves of the ocean.
So perhaps there's a hunkering galaxy, a hunkering universe, six times the mass of our...
Actually, it would have to be more than that because to come out of the universe, it has to be even stronger than the ordinary gravity you'd feel within the universe.
It's because it's coming out of another dimension.
Right.
So in other words, if you scream to someone, your voice dilutes as it spreads out.
Right.
By weight, we can calculate.
Now suppose you're also screaming into another dimension.
Carolyn.
That's exactly what that is.
She's in the TV.
So if you're screaming, then the energy you need to have strength going to that extra dimension and still matter to wherever its head is has got to be much bigger than just went into your own dimensions here.
Every dimension you add, it dilutes faster.
Let me put it that way.
Like for example, if I'm sending marbles down a one-way path, there's no dilution.
Right.
Because all the marbles are just rolling down a path.
Now if I spread it out like this in a fan, now the marbles will dilute into a fan.
Mathematically, they'll dilute as one over R.
Okay?
Now if I, one over the distance, now if I dilute it into a cone, they'll dilute like one over R squared.
Got you.
As does light and as does gravity.
If I now dilute it into a higher dimension than that, it'll dilute like one over the fourth power.
That's funny because you just went, you did.
You went from flat to two to three dimensional.
Right, right.
So the higher, add a dimension.
You need that dimension to get to the other universe.
All right.
So the gravity would have to be like that much more powerful.
But suppose it was.
Suppose at 12 times the mass of our universe, or 100 times the mass of our universe, it could be their gravity seeping into ordinary mass, with ordinary gravity, seeping into our universe.
And since we can't see the origin, which is a mysterious thing.
What is this?
It's just, it's mysterious.
That's wild.
That's right.
Oh my God, and that makes so much sense though.
Well, it really makes so much sense.
Right, right, and here we are trying to touch an elephant that's not even there.
Exactly.
Right.
That is crazy.
So I'm all in for that.
That's the solution I want.
I love it.
Because that would be evidence, indirect though it was, of another parallel universe to us.
That's so wild.
Right, because you know who's looking for the new particle that it could be?
Particle physicists.
Right.
So they're hammers looking for nails.
There you go.
That's it.
So I'm not any of those hammers.
I'm looking for whatever's out there.
Right.
I'll take any of it.
Fantastic, man.
That's good stuff.
Yeah, no, it's a really fun concept.
That's got to be like the cutting edge frontier of all physics.
And just for reference, not that I think everyone got that example, but let me give a simpler one just in case you want it.
Yeah, I mean, I got it, but that's a good example.
If we live within a sheet of paper.
Right.
Right?
And that's your whole world.
Right.
But you're a three-dimensional person looking at we poor creatures.
And you have a hollow sphere.
And we might have done this on another show.
Yes, we did.
If I drop that sphere, pass that sphere through your sheet of paper.
How will you describe that to your other scientists in the sheet of paper?
Well, first there's a dot.
And then the dot.
That becomes a circle.
The circle gets bigger and bigger and bigger.
And then it hits a maximum point.
And then it ends as a circle.
It disappears.
Nice.
Who knows where it went?
I don't know.
Where you just passed a sphere through us.
So there could be higher dimensional things influencing your space environment.
It's the stuff of legends and lores and that sort of thing.
That's cool.
Yeah.
Wow.
All right.
Back to the badge.
Let's do more.
More black holes from the black hole bag.
This is Jackson Welch.
And Jackson Welch from Instagram wants to know, if a solar system further from...
So people can send questions to us from all platforms.
From everywhere.
Okay.
We're everywhere, man.
Instagram, IG.
And he says, if a solar system further from the black hole of our galaxy has a planet which inhabits intelligent life, would time be faster on that planet relative to ours?
Also, if their planet had life develop at the same time as ours, might they be more advanced due to the relative time difference and thus having had quote unquote more time to develop?
So, the gravitational field of the black hole is so weak by the time you get out here.
It's not a thing.
It's just not a thing.
It's not a thing.
So, no, don't lose sleep over that.
Right.
And so, but what is interesting is, and this is like inside baseball here, but it turns out our speeds should be dropping off as you get out.
So, here's the whole galaxy, flat disk spiral galaxy.
As you get farther out, the speed should be dropping off because you're farther away from the center of the action.
But they're not.
They're like stable.
They're quote flat.
So, our speed is the same basically as that of stars orbiting exterior to us.
Something is enabling that to happen.
Something is having them go faster than they otherwise would.
This was a discovery made in 1976 by Vera Rubin, and that was the discovery of dark matter in galaxies themselves.
So, dark matter is actually influencing galaxies to the point where our rotation rate should be slower.
And the dark matter is giving it more gravity to turn.
So, all that means is that we have the same speed, and so therefore there's not any relative anything.
But even if we did start life at the same time, it could easily have life way sooner than we did, or way later, because every branch in the tree of life is an enormous contingency of events.
Suppose the asteroid never took out the dinosaurs.
We would all still be small rodents running underfoot trying to avoid being hors d'oeuvres for...
I'm going to say...
I'm trying to think of the dinosaur now.
T-Rex!
Thank you.
But no, I wanted to go with the clever girl, that one.
Which one is that?
The raptor.
Oh, clever girl!
Velociraptor.
Velociraptor.
Clever girl.
Yeah, I remember that line from Jurassic Park.
Right before he gets eaten.
By the way, you know how big those raptors actually are?
They're about this big.
Oh, really?
They're small.
Yeah, we have them on display.
Oh, in a museum.
They're tiny.
Yeah, I could kick it.
I could totally bust his ass.
That's so funny.
Here I say I'm talking to a fox.
But they pumped them up for the movie.
Just to make them a little more eye to eye.
Right, exactly.
Obviously something big can kill you, but something your size, that's a fight.
That's a fight.
That's a fight that you're going to lose, but it's a fight.
Yeah, it's still a fight.
You think it's a fight, and then you're going to lose it.
Right, and then you get slashed open with these razor-sharp talons of a velociraptor, and you're like, why did I bring a belly to a raptor fight?
I don't know what I'm saying.
So, the point is, almost anything, and we went three billion years with single-celled life.
Right.
If there's something else that pumped oxygen into the air faster than they did, we would have had an oxygenated atmosphere earlier, enabling oxygen metabolism life to take root sooner than it did on another planet perhaps, rather than here, if you want to use Earth as some kind of measure of things.
So, there could be life forms on planets just as old as ours that are a billion times more evolutionarily advanced than we are.
A billion years.
That's funny.
Think about that.
That's great.
Oh, yeah.
That's pretty wild.
You got it.
Yeah.
Dude, I think that's it.
I know we're out of time.
This was it.
Wait, wait.
Stick your head in there.
Tell me how many questions are left.
All right.
Well, thanks for tuning in.
Nobody tunes anything anymore.
This is true.
Thanks for...
Thanks for clicking on.
Click, yeah, whatever you did to hear this.
Thanks for listening, watching.
This has been StarTalk Cosmic Queries edition, Black Holes and Dark Energy.
Chuck Nice, always good to have you in.
Thank you.
Always a pleasure, brother.
All right.
I'm Neil deGrasse Tyson.
You're a personal astrophysicist.
Signing off from my office at the Hayden Planetarium, where I'm telling you, as I always do, to keep looking up.
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