Near colliding NGC 2207 and IC 2163 as seen by the NASA/ESA Hubble Space Telescope.
Near colliding NGC 2207 and IC 2163 as seen by the NASA/ESA Hubble Space Telescope.

Cosmic Queries – Back to School Edition

NASA/ESA and The Hubble Heritage Team (STScI), Public domain, via Wikimedia Commons
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About This Episode

What do you wish you had learned in school? On this episode, Neil deGrasse Tyson and comic co-host Chuck Nice go back to school to answer questions about simulation theory, time dilation, white holes, the sound of space, and more!

What happens after you die? Where does oil come from? We answer fan questions from the Internet about what they wish they had learned in school. Explore the carboniferous era, why trees need microbes, and what we know about death. Are we living in a simulation? 

What sound does space make? We explain the sound of silence, how old our sun is, and time dilation. We cover an essential question: do we live on Earth or do we live in Earth? Neil settles the debate once and for all. Could time travel exist? We go over different paradoxes and the trouble with doubling back on your own worldline. 

In a nutshell: what is quantum physics? Why is your reflection opposite in a mirror? How does nuclear energy work? Hear Neil explain it both quickly and well. What is a white hole? Are there stars that don’t have galaxies? Or planets that don’t have stars? Could it be possible that the Big Bang occurs on a regular basis? All that and more on another cosmic queries episode! 

Thanks to our Patrons Goat34, Mark Dent, Edwin J Roldan, Evan Moorhead, and Abby GIll for supporting us this week.

NOTE: StarTalk+ Patrons can watch or listen to this entire episode commercial-free.

About the prints that flank Neil in this video:

“Black Swan” & “White Swan” limited edition serigraph prints by Coast Salish artist Jane Kwatleematt Marston. For more information about this artist and her work, visit Inuit Gallery of Vancouver.

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 Cosmic Queries Edition. Chuck, co-host, always good to have you, man. Always a pleasure to be here. How are...

Welcome to StarTalk, your place in the universe where science and pop culture collide.

StarTalk begins right now.

This is StarTalk Cosmic Queries Edition.

Chuck, co-host, always good to have you, man.

Always a pleasure to be here.

How are you?

Yeah, this one I figured, let’s do an homage to going back to school.

Why not?

So this is the back to school edition.

Not only people who are actually going back to school, but people who might, I don’t know how many out there feel this way, who might look nostalgically on having been in school.

Your only job in life was to learn.

Yes.

See?

Yes.

See, that’s a thing.

To the two of you out there.

The two people.

Everyone else is a fan of Alice Cooper.

School’s out for summer.

Yes.

School’s out for summer.

Yeah, those folks were learning there.

He’s lied because school is never out.

That’s what people don’t get.

School is…

Provided they instill a level of curiosity in you so that you can become a lifelong learner.

I disagree.

I disagree.

Okay, you are a lifelong learner whether you want to be or not.

It just depends on how you want to learn.

No, I’ve met some ossified people.

They ain’t learning a damn thing.

So don’t tell me.

Nah, yeah, well.

No, it’s like, no, they’re learning the hard way.

The hard way.

That’s all.

So what do you got?

So for this back to school edition, we’re expanding our reach, going to our TikTok following and our…

What?

Twitter following.

Yeah.

Oh, yes.

So they might become Patreon members one day.

So we’ll reach there and give them a taste of what’s otherwise behind the protected space.

Right.

So if you want to go to patreon.com/startalk and you can support us and then you will receive what we’re doing right now as a command performance.

A private show just for you where Neil answers all of our Patreon patrons’ questions.

But this time we’re extending it to anybody on TikTok and Instagram.

Of our fan base in those platforms.

Yes.

Everybody gets one free.

Plus, you’re not supposed to ask for money before we did anything for them.

I like to get the money up front.

Up front.

I got you.

Up front.

We solicited the questions.

It was, is there anything you wished you had learned in school or want to still learn?

Did we pose that question?

Okay.

Basically, yeah.

There we go.

So, anything you wish you had learned, want to still learn, or just may be curious about now?

Yeah.

Let’s do it.

So, here we go.

This is Travel For Real from TikTok.

And Travel For Real says, by the way, his name is Josh.

He says, is there any scientific evidence for what happens before or after this life?

Oh, yes.

Uh-huh.

Yes.

Well, in the sense that everything we know about who you are as an individual, everything emanates from the electrochemical phenomena in your brain.

And we know this because people who get a series of mini strokes, little bits of them begin to go away.

First, you know, kinetically with their muscles, but also in their mind.

And so they slowly go away.

Then whoever you remember to be there, bit by bit is being disassembled by the loss of electrochemical functions in the brain.

And so you get to a point where a person totally strokes out and their body might even still be alive, the rest of their body, but they don’t function.

Their pupils don’t dilate or constrict.

They’re brain dead, basically, at that point.

But the very deep part of the brain that keeps the body alive, the body is still doing what it’s doing.

So as far as we know, when you die, since all of the neurosynaptic phenomena cease, you enter a state of non-existence.

Period.

And is that any different from your state of non-existence that was before you were born?

Mm-hmm.

Chuck, before you were born, you know, 10 years before you were born, you’re not saying, where am I?

How come I’m not in the world?

That’s how I got here.

You snuck in the back.

So you’re not lamenting your state of non-existence before you were born.

And all evidence points that after you die, you reenter a state of non-existence.

It’s that simple.

By the way, there are many people who don’t like that answer.

No, they don’t.

That’s what science tells us, but they don’t like the answer.

They need there to be things after you die.

Paradise.

Paradise of any kind described in multiple religions.

And if you’re into reincarnation, you will believe you were a life form before your current one.

So there are belief systems out there that say all kinds of things about before you’re born and after you die.

But if you’re going to ask a scientist, that’s the answer you’re going to get.

So what that tells me is, as a scientist, that I have to make this life count.

Because there’s not one that’s after it.

This life is more than just a read through, which is the chili peppers way of saying it.

Oh, a real read through.

Interesting.

You have power and agency over your ambitions, your goals, where you land, where you launch from.

This ain’t no rehearsal, baby.

Yep, that’s it.

The one and only.

Make it count.

All right.

Keep it going.

Oh, by the way, there’s a whole chapter in my next book on life and death, where all these topics are addressed, in case you want to read up on them even further.

Yes, if you want to be more depressed than you are now.

That’s right.

Yeah.

So, there you go.

All right.

That’s very cool.

This is Josh.

And Josh says this, okay, I’m just reading them and I don’t judge.

He says…

You kind of are, just I’m saying, but go on.

All right.

Okay, go.

You called me out.

Go, Josh.

He says, what was first, dinosaur or water or trees?

And did the comet really take out the dinosaurs?

All right.

So, water was around…

Always first.

Yeah, water was there from the beginning of things.

In space.

In space.

Water is in space.

So, we got water.

Water is a comet.

It’s because hydrogen and oxygen are both comet in the universe.

So, putting them together to make H2O, you got that one for free.

Next came trees.

Then came dinosaurs in that order.

And the cool part is, there’s a time when we had trees, but no microbes to digest the wood.

Right.

So, a tree would grow, fall over and die.

And there would be nothing for it to decompose.

We are so accustomed to seeing a fallen tree in the forest that is crumbling back to soil.

In the presence of microbes and insects.

And if it’s old enough, you can take your hand and just crush it.

Crush it.

Crush it into dust.

Okay.

Look how strong I am.

That did not happen.

There’s a point when that did not happen.

All the trees accumulated and there’s an entire layer in the geologic strata called the carboniferous era where all the trees and other vegetation collapsed and did not decompose.

And out of that carboniferous era, we get our coal and oil.

Right.

There it is.

And that’s why, yeah.

And everybody says this.

I’m glad you just said this.

Out of the carboniferous era, we get coal and oil because fossil fuels means buried.

It doesn’t mean dinosaur.

Oh, right, right.

Yeah.

In fact, the oil, we used to think that there was an ad for the oil company that used a brontosaurus, who was a Sinclair.

So Sinclair had a brontosaurus.

I think one of their commercials implied that all the oil came from dead dinosaurs, but it’s mostly from vegetation.

From vegetation.

That never decomposed.

In the usual way, gets buried and under long times of pressure and temperature, there’s a chemical change that boosts it with the kind of energy you want for an industrialized civilization.

Yeah.

Oh, by the way, and dinosaurs, they’re still around, they’re called birds.

That’s true, right?

That’s very, you know, yeah, then that’s the, I didn’t see it, but I hear that’s the whole big reveal in the latest Jurassic Park is that the dinosaurs have feathers.

Yeah.

Yeah.

And that would be the trend, the likely link between the modern day birds and what they were.

Right.

That’s right.

But by the way, trees are not the oldest things around.

There are other sort of vertebrate life forms that predate trees.

Right.

So, sharks are older than trees, for example.

So, anyhow, it’s fascinating the history of life on Earth and who came first and who didn’t.

Here’s one for you.

You ready?

Mm-hmm.

We all…

Nobody doesn’t love Stegosaurus, right?

Of course.

Yeah.

It looks like his own castle.

Yes.

Or his own armor.

His own armor.

Yeah.

Yeah, yeah, yeah.

So, Stegosaurus…

And so, we are…

So, Stegosaurus predates T-Rex.

By how much?

By more than T-Rex predates us.

Oh my goodness.

Right?

So, Stegosaurus is like the old man of the dinosaurs.

Stegosaurus is the OG…

So, we are closer…

T-Rex.

in time to T-Rex than T-Rex is to the Stegosaurus.

I thought I’d throw that out there.

There you go.

Show some respect, T-Rex.

That’s right.

You don’t know who you’re messing with.

Stegosaurus.

That’s kind of dope.

It’s totally the OG of dinosaurs.

Who knew that?

I did not know that.

That’s a long time.

That’s a long time.

And you know what upset me?

When we did more calculations with the stability of Saturn’s rings, which is just a swarm of particles in orbit, not entirely stable, that there was some talk that Saturn’s rings were only around for maybe 50 million years, at most 100 million years.

So there’s a chance that if the dinosaurs had a telescope and they looked up at Saturn, they would see no ring at all.

Wow.

Yeah.

And that would be sad.

That’d be sad for me if I was a dinosaur because I love Saturn.

Yeah.

It was probably sadder for T-Rex because his arms are too short to try and use a telescope.

Arms are too short for everything.

It’s just like, you know, God, why can’t I get this?

All right.

Yeah, that’s okay.

Very cool.

Very cool.

Very cool.

Let’s go to Lenscape via TikTok.

All right, Lenscape just wants to jump into like a whole bath of goodness all at once.

Let’s do that.

Neil, are we living in a simulation?

I am not as convinced as other people are.

And again, I hate to sound like a broken record, but in my book, I give an argument.

I call it the inanity defense for why we’re not a simulation.

Because every computer we’ve ever programmed to do any task at all is vastly more logical than we have ever been.

Vastly more sensible, vastly more traceable in the causes and effects of what it does.

So if we’re a simulation, someone would have to program the computer for its characters to make completely irrational, stupid decisions that we make every day of our lives.

And who would do that?

That’s all I’m saying.

So I’m thinking a simulated universe, all of its life forms would be way more logical and rational than any evidence humans have ever given for behaving that way.

So that’s where I’m coming from here.

I call it the inanity defense.

Right.

But here’s the thing, the inanity is far more interesting.

So if you’re a designer, why wouldn’t you do that?

Yeah, but you wouldn’t need to do it to this depth.

I mean, you could throw in a few irrational players, right, and everybody’s got to deal with them.

But the extent, the breadth and the depth of which it appears, clearly no computer was involved.

Yeah, okay.

I got you.

Yeah, okay.

It’s like, there’s crazy and then there’s us.

That’s basically what it comes down to.

No computer could be this crazy.

They can’t.

They got silicon chips that have, you know, logical circuitry.

So there you go.

All right.

Very cool.

Like, bring me another one.

Here we go.

So this is Seth Pasquale says this, 25, Seth Pasquale’s 25.

What sound does space make if you were to float around in it?

So in other words, what would you hear if you’re in the nothingness of space?

Gotcha.

And we will get to that when we come back from our break.

Ooh.

First segment over.

When we come back, more Cosmic Queries, back to school edition.

Everything you thought you should have learned in school or you wanted to learn in school.

Mm-hmm.

When StarTalk returns.

Hi, I’m Chris Cohen from Hallworth, New Jersey, and I support StarTalk on Patreon.

Please enjoy this episode of StarTalk Radio with your and my favorite personal astrophysicist, Neil deGrasse Tyson.

We’re back, Cosmic Queries.

So we left off with a question, Chuck, what was it?

And who asked it?

Yes, this was Seth Pasquale 25, and he says, what’s Seth?

From what?

From TikTok.

TikTok, okay.

And he says, what sound does space make if you were to float around in it?

What do you hear if you’re just out in the nothingness of space?

You’ll hear Darth Vader, no, that’s a bad Darth Vader, sorry.

You’ll hear nothing.

There’s no medium to communicate sound from any place in space to your ears.

So what you’ll begin to hear are things inside your body.

So I was in the quietest place on Earth, and it is a room at Bell Telephone Laboratories in Murray Hill, New Jersey.

And every bit of sound that would be exterior to the room doesn’t get in.

And any sound that you make gets completely deadened against the walls.

You’re not even standing on a floor.

You’re standing on a mesh that is equidistant between a ceiling and a floor, but then the floor below you, which is also made of specially designed acoustic materials.

So I’m standing in there and you don’t hear anything.

You don’t hear anything.

I started hearing blood pumping through my ear canal.

Wow.

Now, are you sure you weren’t having a stroke?

No, I hope not.

Being from New York and for the first time, hearing absolutely nothing.

Your brain just couldn’t take it.

My body freaked out.

Your brain started to explode or implode.

Yeah, so at the end of the day, allow me to say there is no such thing as the sound of silence, other than blood moving within your skull.

Oh man, Simon and Garfunkel hates you right there.

Yeah, yeah.

Yeah, oh well.

There you go, so you hear yourself.

That’s the sound of silence, which is nothing.

Nothing, nothing.

Another way to say it is the sound of silence is the sound of things that were always making noise that you never noticed before.

Ooh.

How about that?

Look at that, far more profound.

Yeah, yeah, exactly.

So in other words, you need to Miyagi this and listen to yourself a little closer.

There’s a saying attributed to Nietzsche, and this I quote in the book too.

Damn, my life just is the book.

No, right now it is.

It’s those who were dancing were deemed insane by those who could not hear the music.

And just think about it, if you watch people behind a glass screen dancing and you can’t hear the music, they’re crazy people.

They look insane, right?

They look insane.

They’re jumping up and down, flailing their arms and legs.

So I think there’s a lot in that quote in terms of what is the reality that you experienced versus that of others.

And what is it that you define as that which is objectively true?

And always think twice before you pass judgment of what you see others doing.

Maybe it’s because they hear the music and you do not.

All right, here we go.

This is ZaMarian from TikTok.

ZaMarian says, how old do you think our star really is?

Is it possible that it’s older than we think?

Is it okay?

I mean, is it lying about its age?

I mean, is our star going like, you know?

The sun is telling us how old it is.

And Chuck, right, it could be lying.

I don’t know the issues with stars, but if they have social issues that where this matters.

Most stars, most stars lie about the age.

So all the evidence we have tells us that our star is about four and a half to 4.6 billion years old, slightly older than Earth, Moon system itself.

And we expect it to live another five billion years in good health.

There you go.

Before it expands and then engulfs the orbits of Mercury, Venus and Earth, vaporizing the oceans and then the atmosphere and then all life as we know it.

So have a nice day.

There you go.

And that’s our show people.

Sleep well, sleep well.

There you go.

All right, that’s very cool.

So now how old is the Earth of the?

4.55.

Five, yeah.

4.55 billion years.

We all, everything kind of coalesced in that time, right?

Exactly, so you can ask, what are the chances of that being wrong?

I suppose there’s a chance, but it has so much supporting evidence that we’re on to the next questions.

No longer even judging whether those estimates are false.

Any further, because they’re so successful.

That’s right.

God, there you go.

Okay, that’s the name of a user?

That’s Lil Toenail from TikTok.

All right.

You gotta love that.

Okay, here’s the deal.

Lil Toenail says, I cannot wrap my head around time dilation.

Can you please explain it to me?

And I’m like, who knew Lil Toenail had a head?

You’re scraping the bottom of the barrel for that one.

I don’t know.

No, I’m just saying, something’s going on with that foot.

If the foot is doing that thing.

That’s what-

What’s the big toe thinking?

What’s the big toe thinking?

If Lil Toenail is worried about time dilation.

Oh, what the hell is big toe?

So here’s the thing.

We have two coordinates that define us, where we are in space and where we are in time.

You can, if you were sitting your butt in one place, you were moving forward in time, but you’re stationary in space, okay?

If you are a speed of light, you are moving forward in space, but you’re stationary in time.

Time does not tick for light.

If you are anything in between those two extremes, there’ll be a combination of your space changing and your time changing, the rate at which time ticks.

Because both of those matter to figure out where everything is and where it’s going in the universe.

So you can think of it as two axes, a space axis and a time axis, and light moves along the space axis, and again, if you are sitting there not moving at all, you move perfectly along the time axis.

You can find other places in that chart where space and time are moving at various rates relative to each other.

And so the GPS satellites, for example, they are in a different place.

They are farther away from Earth’s gravity.

So their space-time diagram means time ticks more slowly for them than it does for us.

So when they tell you what time it is, we have to precorrect it with an Einsteinian equation so that the time you get on Earth’s surface matches what everybody else is using.

It’s amazing.

It’s completely amazing.

That’s right.

So cool.

That is so cool.

So trippy.

And Einstein didn’t even get the Nobel Prize for that.

He got it from much lesser work.

Had they totally done his Nobel Prize some justice, he would have had like eight Nobel Prizes.

Yeah.

Because, I mean, yeah.

Figuring out that time ticks more slowly.

Correct.

I mean, that’s beyond mind blowing.

That is beyond, that is a tectonic perspective shift on the entire universe itself.

Yes, it is.

Einstein changed the cosmic perspective.

I feel so stupid right now.

I love that so much.

I can never get enough of that.

Wait, wait, don’t confuse being stupid and not knowing with being curious and eager to find out.

Can I be both and?

No, no.

I’m not giving you that.

I have more confidence in you.

Okay, good.

All right.

This is Madero Madden, oh, Maddie Rose Madden.

Maddie Rose Madden from TikTok.

Okay, check this out.

You get in the middle of perhaps a spousal argument here, Neil.

Just letting you know right now.

All right.

Do we live in or on the earth?

Earth, my husband says that we live in the earth because of the atmosphere.

I say we live on the earth because the earth’s atmosphere is on the earth.

Okay, all right, what do we got here?

I mean.

I’m gonna settle this.

You must bring peace to this home.

All right, you ready?

Okay, before 1970, if you, no, before 1968, if you said draw earth, people would draw a globe and they would draw oceans and they’d draw the continents.

Correct.

Nobody drew clouds.

That’s right.

Take a look at any old image of earth.

There are no clouds on it.

Not even Star Trek, which should have known better.

You know, how does it begin?

Space, the final frontier, these are the voyages.

And you see earth in the background, there’s no clouds on it.

So no one thought about our atmosphere as something fundamental to the identity of earth.

Until 1968 with Apollo 8, went to the moon, looked back, took a picture of the earth and there it was.

As only nature intended you to see it.

With oceans, land, clouds.

Do you realize after 1968, that was December 68, there was legislation to create and was ultimately signed a year and a half later, the National Oceanic and Atmospheric Administration.

Before then, no one had connected the oceans and the air before.

Hadn’t been done yet.

There were atmosphere people and there were ocean people.

And you had land people.

Then you had people studying lights.

And so the geologists and the biologists, now we find that life is thriving throughout the earth, on rocks, down through the crust of the earth.

And that oceans interact with our land masses, changing their shapes.

And where does the ocean, where does the atmosphere get its water from?

It gets it from the ocean.

This is an entire system.

So since then, nobody draws earth without clouds.

So I declare by authority vested in me, by the universe, and most specifically by the cosmic perspective, that if someone wants to say that living on earth’s surface, beneath 15 pounds per square inch of atmospheric mass, if they want to say we live in the earth, I’m all for it.

Otherwise, you’d have to say earth does not include the atmosphere, and I’m not prepared to do that.

But I think I justified it, right?

I didn’t just say, we have my opinion.

And by the way, earth’s atmosphere is so.

Earth’s atmosphere is to earth as the skin of an apple is to the apples.

That’s just terrible.

Okay.

I mean, the way we treat the atmosphere, that’s why I say it’s terrible.

Oh, yeah, right, right.

You think you’re in the bottom of a large ocean?

No, you’re at the bottom of a really skinny, skinny thing.

And just because you’re little, that it looks big.

But when you’re big, it looks little.

It is.

So we live in earth, people.

In earth.

Yeah.

Which makes sense because this is a spaceship hurling through space.

Correct.

So you wouldn’t travel on a spaceship.

You travel in a spaceship.

Yes, correct.

As George Carlin clearly noted, where he gets, you might be getting on the plane, he’s getting in the plane.

I didn’t, I never heard that.

You never heard that?

Oh, that’s in his airplane segment.

Yeah.

I like it.

Okay.

Look at that.

Sorry, Maddie Rose Madden.

You’re going to be mad when you hear this, but.

Wait, wait, wait.

I got another one.

So do you live in a city or on a city?

Well, see, I live in a city.

No, no.

You see, the city has a grid and you’re standing on the grid of the city, right?

Yeah.

You’re in three dimensions.

If you were flat and you crossed the border of the city, you’d be in the city, but you stand up above the city or on the city.

Well, I’m down to be on the city.

What do you think of that?

I’m on the town, baby.

I’m all about it.

That sounds good.

How about it’s Sasha 2020 from TikTok says this, okay.

Are there time machines?

Now specifically, I’m taking this question seriously because I’ve heard you speak to this.

And then a second question.

Do you think people will be able to time travel?

I can answer both when we come back from the break.

We’re done with our second segment of Cosmic Queries back to school edition.

Stuff you wanted to learn in school and didn’t?

Or want to put back in the curriculum so others can?

How about that?

When we come back.

We’re back to StarTalk Cosmic Queries Back to School Edition, reaching out beyond our Patreon core supporters to others who might enjoy this and become a supporter as well.

And Chuck, you left off someone, who is it that asked the question?

It’s Sasha 2020.

It’s Sasha 2020.

Yeah, she asked a compound question, but it’s two separate questions, but are there time machines, and do you think people will be able to one day time travel?

So there you go.

Okay, Tom, old enough, perhaps you, Chuck, too, no, you’re not, I just remembered how old you are.

I’m old enough to remember there was a TV show called Time Tunnel, where it was in the 1970s, and the scientists invented this tunnel, and you walk in and you can travel back in time.

Clearly, something goes wrong, otherwise it wouldn’t be a TV show.

So they get lost in time, and they’re bouncing back in different times.

So the pilot episode, guess where they went?

Camden, New Jersey.

No, they went back to the Titanic.

Of course.

And for a while there, people that might be because of that show, people were interviewed, where would you want to go the most?

They said, I want to go back to the Titanic.

So we have evidence that at some point, time machines are invented, because all of those people went back to the Titanic, and they were too heavy for the Titanic, and that’s what sunk them.

And it sunk the Titanic.

That’s what sunk the Titanic.

All of the time travelers who went back to the Titanic to see it sink.

That’s what actually sunk the Titanic.

So the real question is, if there are time, oh, Stephen Hawking held a party, okay, for all time travelers of the future.

And he said, if you’re a time traveler, we will expect you to show up right in front of me, and if he summons you, that you gotta show up, right?

Because it’s Stephen Hawking.

That’s Stephen Hawking.

And he’s sitting there in his wheelchair, and everybody’s around, and they got an open summon, and nobody appears.

So that could mean that a time machine will never be invented in the future, or it’s invented, but there’s a law of physics that prevents you from going back in time, just because of the risks involved.

The risks.

Now in The Terminator, what did he do?

Well, he basically had to save his son?

No, no, no, no, no.

He had to make sure the leader of the…

Chuck, what country are you?

Are you American?

Are you…

No!

He had to make sure the person who led the revolution against the machine was never born.

He had to make sure he’d never exist.

Oh, The Terminator, I thought you meant the guy that was sent back to help Sarah Connor.

Yeah, but you’re talking about The Terminator himself.

He went back to kill John Connor before he was born.

Correct.

And so doing you kill the mother, okay?

And so this is so violent, though.

It’s so violent.

All you have to do is prevent the mother from meeting the man who she had sex with to…

To make John Connor.

To create John…

That’s all you have to do.

You have to kill everybody.

But that’s what made Terminator so great.

The guy that he sent back to protect her ended up being John Connor’s dad.

So if The Terminator never went back to kill John Connor, John Connor would have never been born in the first place because The Terminator was really like the Tinder for John Connor and Sarah Connor.

So The Terminator’s a time idiot.

Right, he could not figure that out.

He made them, he made that happen.

Right, so point is, there could be some, as Hawking suggested, a time travel conjecture that says you can’t travel back in time, but if you do, you’ll have no access to any world line that you ever touched.

Because if you somehow trip up your grandmother, then your mother is never born or your father’s never born and then you’re never born.

And then you would not have been alive to go back to trip them up.

And the Terminator version of that is you kill everybody.

So anyhow, so yeah, no, we think no.

There you go.

We think no, no, no time machine.

Oh wait, wait, by the way, in the science march, by the way, if scientists have to march, you should be worried, you should be worried.

Am I right here, Chuck?

Yeah, without a doubt.

If nerds go on the march, something’s seriously wrong with society, okay?

Yeah, when nerds run amok, society has gone really in a twillet.

That’s not what I said, but fine.

But they run amok.

So one of them held a poster that said, in a chant, what do we want?

Time machine.

When do we want it?

It doesn’t matter.

That’s funny, okay.

All right.

I like that.

All right, here we go.

This is hayverse.x from Instagram.

Hayverse, spell that.

H-A-Y-B-E-R-S-E, hayverse.

Hayverse, wow, okay.

Yeah, like the universe, but just hayverse.

All right, yeah.

So it says, this is a good one.

As quickly and succinctly as possible, please explain quantum physics in a simple way.

Oh, heck, I can do that.

So this is from TikTok?

Instagram.

Instagram, oh.

Because if it’s TikTok and he’s saying explain it quickly and simply, that’s a TikTok virus that he’s got there.

Right, right, right, right.

Where everything’s got to be fast and big.

So all I can say is, as you look to smaller and smaller things in the universe, whole other laws that dictate what they do and how they do it kick in.

And so quantum physics is the theory of the small that describes atoms, molecules, subatomic particles.

And if you get larger and larger, those laws still apply, but they get averaged out and we get what’s called classical physics.

So we need it to understand atoms and molecules.

And there is no information technology, the creation storage and retrieval of information.

There is no IT without an exploitation of the quantum.

So it’s not just some idle curiosity from boneheaded, you know, pointy headed physicists.

It’s a fundamental part of what we consider modern civilization.

There you go.

What are you doing, gluon?

Your laws don’t apply to me.

Let’s go, let’s do a lightning round.

Here we go.

All right.

Lightning round, I answer in sound bites.

Okay, go.

Nico Duques7 says this from Instagram, why do I see myself inverted when I look in the mirror?

I hope you’re not inverted, but you’re swapped left and right.

If you’re upside down in a mirror.

The reason is, is because you’re in an alternate universe.

Actually, there’s a curvature you can give to the mirror where you are, in fact, upside down.

So the beauty mirror is if you back up away from them, you’ll see yourself upside down in them.

So if you’re upside down in a mirror, it’s a fun house mirror.

But otherwise, you are reflected left and right, but not top to bottom, because what’s actually happening is you are being reflected through a line that goes through the center of your body.

So your nose gets reflected to the other side of your nose, your cheeks go to the other side, and everything starts here and moves through the mirror and shows up on the other side.

So reflection is not what you think it is.

It’s not just simply let’s swap left and right.

You’re actually recreating yourself through the mirror with these reflections.

So that’s why.

Look at that.

And by the way, that reflection has a whole life of its own.

And when you walk away from that mirror, it walks away to go through stuff that you don’t even know anything about.

And you’ll get blamed for it, right?

And you’ll get blamed for it.

So.

You got it.

All right, here we go.

Srivastava.

Okay, whatever.

I want to hear the person’s last name.

Harsharaj.

Harsharaj.

Harsharaj.

H-A-R-S-H-A-R-J.

Harsharaj.

Harsharaj, okay.

Harsharaj.

That wasn’t that hard, was it, Chuck?

No, it wasn’t.

It wasn’t, Srivasta Harsharaj says this.

From where?

From Instagram.

And this is all it says, maybe you’ll get it.

Time travel paradoxes?

So, the funny thing about paradoxes is that there aren’t any.

The paradox is a paradox to you because you haven’t really calculated it correctly.

The time travel paradox is, I send you off and you’re moving at a high speed and I see that your time is ticking slowly.

Whereas you don’t know that because it’s just your clock and your heart rate and as far as you’re concerned, everything is normal.

But you see me on earth receding away from you with my time ticking slowly.

So how can we both see each other’s time ticking slowly?

It’s called a twin paradox if you want to.

You send off a twin, how does that twin you sent off become younger than you when they look back at you and time is moving more slowly for you as well?

It’s because when you come back, you lose that effect.

So I can send you away, but when you slow down, turn around and come back, that changes your relationship to me in the universe.

You’re the one that’s accelerating, not I in this.

And the one who’s accelerating will feel the effects of the time dilation relative to me.

But if you just kept going, I would think your time had slowed down forever, just as you would think my time had slowed down.

So it’s a matter of, do you slow down, turn around and come back?

And to do so, you decelerated and accelerated and that changes the game.

There you have it.

All right.

That was a very good explanation.

That wasn’t very soundbitey, but I’ll keep trying.

No, that was a very good explanation though.

That’s how it goes.

All right, here’s another one.

This is Anton, Antonisvina says this, from Instagram, please explain nuclear energy quickly and well.

I love it, I love it.

No room for me to mess up here, right, right, right?

So, energy has something, it is an entity that has the capacity to do work, okay?

That’s basically the definition of energy.

You can store the energy to do work later, okay?

And that’s where you have, like if you have a hot pack, if you have a hot pack, and it’s just room temperature until you’re spraying your knee, and then at the softball game, they slap it on the ground and shake it and bake it, shake it and jiggle it, that releases chemical energy that had been bound into the molecules themselves.

That’s chemical energy.

Well, inside the nucleus, there’s also energy.

If you break apart some nuclei, it’ll release energy.

And that’s all nuclear energy is, the energy contained in a nucleus.

As opposed to chemical energy, which is the energy contained in the molecules.

Right.

So there you go.

It’s simple.

It’s really not that complicated.

That’s right.

That’s it.

That’s it.

That’s really, I mean, that’s, hey, quickly and well, that was it.

Quickly and well, baby.

All right, here we go.

This is lary2602279 on Instagram says, does every star belong to a galaxy or are there also lonely stars?

Okay, we have a word for them to call vagabond stars.

Yeah.

And if they’re vagabond stars, could there also be vagabond planets?

We think some planets, when they’re trying to form in their star system, get ejected and then they wander through space, basically homeless, right?

But many planets have interior heat like we do.

So if you have a source of heat, you might be able to still sustain life, even though you’re not near any stars at all.

So that’s an interesting side light about vagabond planets.

But vagabond stars?

Sure, in fact, one of my early research projects was on that very topic.

They’re called intergalactic supernovae.

So these are stars that would be kicked out of their host galaxy and then explode and you’d see them exploding far away from their brethren.

And they had no business being that far out.

So as far as we know, yes, there could be very many as well.

I don’t need y’all anyway.

I’ve been kicked out of better galaxies than this.

Chuck, you sound like you’ve actually had to say that in real life at one point.

That came out so smoothly and quickly.

Yeah, that was all I could say was well rehearsed.

That was.

I’ve been kicked out of better joints.

All right.

All right, here we go.

This is Shane Vinnie.

And Shane Vinnie says this.

Could the Big Bang or Big Bang type events occur regularly?

We think in the multiverse, yes.

That we’re just one of multiple bangs that are happening all the time.

So regularly on that scale, yes.

There’s nothing stopping it because of what the powers of the multiverse actually are.

They’re a universe birthing machine.

But in terms of our own universe, not so much.

No, we don’t think that’s what’s going on.

And then he says, or she says, or they say, white holes, maybe?

White holes for what?

Does this follow on to that?

Yes, so could the Big Bang, I’m not sure what a white hole is.

Yeah, well, we thought, okay, for a while, when white holes got discovered, there was like the mathematical opposite of a black hole.

All right, you know what it’s like?

You know what it’s like?

So, if I say, what’s three squared?

What would you tell me?

Six, nine.

Let’s try that again.

Chuck, fifth grade math, what’s three squared, three times three?

Nine.

Okay, so now I say, what’s the square root of nine?

Well, three.

Three, of course, but it’s also negative three.

That’s right.

Because negative three times negative three is also nine.

So, when you do the equations for a black hole, there’s a second solution.

So, it’s like the opposite solution to a black hole.

Black holes eat everything, white holes emit everything.

So, we calculated what these should look like in the universe, looked around it, we didn’t find a lick of them.

But it would be cool if white holes were birthing universes, but we have no real evidence of that.

No, what white holes do is they use black holes to do all their work.

And then they might colonize the universe, but.

Chuck.

Do not write people, that was funny.

That was funny, I’ll give a damn.

Dude, you better not write, and I’m serious.

They’re called jokes.

No, I’ll say, I’ll say, everyone, Chuck still has, he’s got a black thing going on inside of him.

Yeah, he’s got issues.

Yeah, he can’t shake it, I can’t shake it.

We had a show on contagious diseases, and we talked about the black plague, and Chuck said, why everything bad gotta be black?

That’s right, gotta be the black plague.

Nothing gets by, Chuck.

All right, so we need you to highlight that in almost every case.

But Chuck, we gotta call it quits, we got through a lot of questions there.

Wow, we did.

That was good, we can do that again.

Yeah, that was a lot of fun.

Thank you all from TikTok and Instagram, the rest of our fan platforms.

And we’re happy to serve you.

And thanks for sending in your questions.

Chuck, always good to have you, man.

Always a pleasure.

This has been StarTalk, Neil deGrasse Tyson here.

Your personal astrophysicist.

Keep looking out.

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