The “Bang” in Big Bang with Charles Liu

Summary

StarTalk Radio Episode Summary: "The “Bang” in Big Bang with Charles Liu"

Podcast Information:

• Title: StarTalk Radio
• Host: Neil deGrasse Tyson
• Guest: Charles Liu
• Release Date: February 4, 2025
• Description: Science, pop culture, and comedy collide as astrophysicist Neil deGrasse Tyson and his co-hosts delve into astronomy, physics, and the mysteries of the universe.

---

Introduction to Cosmic Queries

[01:31] Neil deGrasse Tyson:
Neil welcomes co-host Paul Mercurio and guest Charles Liu, setting the stage for an engaging discussion on cosmic phenomena. The trio embarks on a "grab bag cosmic queries" segment, where they tackle intriguing questions from listeners worldwide.

Diffusion in Space vs. Earth

[04:03] Paul Mercurio:
Brian from Roseville, California, asks why giant gas clouds and nebulae exist in space without dispersing like clouds on Earth.

[04:19] Neil deGrasse Tyson:
Neil explains that in space, the vast vacuum and low temperatures allow gas particles to remain cohesive. Unlike Earth's atmosphere, where gas disperses rapidly, gravitational forces in space can counteract this diffusion.

[07:04] Charles Liu:
Charles adds, “The conditions out in space make it so that these gas particles tend to disperse unless they have a reason to collect,” emphasizing the role of gravity in forming structures like stars and planets.

Notable Quote:
Charles Liu [07:04]: "The conditions out in space make it so that these gas particles tend to disperse unless they have a reason to collect."

Understanding Gravitational Waves

[26:31] Paul Mercurio:
Mitchell Ransom from the UK inquires about the significance of gravitational waves and what they reveal about the universe.

[27:49] Charles Liu:
Charles likens gravitational waves to ripples in a pond, stating, “Gravitational waves literally have the opportunity, if we're sensitive enough to detect them, to tell us about spacetime, the structure of the universe.”

[28:17] Neil deGrasse Tyson:
Neil elaborates on how gravitational waves provide insights into cosmic events and the fabric of spacetime, comparing their detection to observing ripples that inform us about underlying structures.

Notable Quote:
Charles Liu [29:28]: "Gravitational waves literally have the opportunity...to tell us about spacetime, the structure of the universe."

The Big Bang: What Really Happened?

[11:55] Paul Mercurio:
Chris Wynn from Ottawa, Ontario, Canada, poses a question: "During the Big Bang, what went bang? If we don’t know, what are your best guesses?"

[12:00] Paul Mercurio:
Paul critiques the terminology, saying, “The term Big Bang is so misleading because it’s about expansion, not about bang,” urging for more accurate scientific language.

[12:12] Charles Liu:
Charles explains the origin of the term "Big Bang," attributing it to Fred Hoyle’s skeptical view of the universe's origins, highlighting its lasting impact despite being somewhat misleading.

[13:15] Neil deGrasse Tyson:
Neil reinforces the concept by clarifying that the Big Bang represents the expansion of space and time from an extremely hot and dense state, not an explosion in the traditional sense.

Notable Quote:
Paul Mercurio [13:15]: "The term Big Bang is so misleading because it’s about expansion, not about bang."

Cosmic Inflation and Galactic Collisions

[13:37] Charles Liu:
Charles delves into cosmic inflation, describing it as an "expansion within an expansion," analogous to blowing up a balloon rapidly after a slow start.

[16:10] Neil deGrasse Tyson:
Neil recounts historical perspectives on cosmic inflation and galaxy mergers, discussing how galaxies collide and interact, shaping their structures without direct star collisions.

[37:00] Charles Liu:
Charles introduces the concept of the "impact parameter," explaining how galaxies influence each other's trajectories through gravitational forces without direct collisions.

Notable Quote:
Charles Liu [37:00]: "There is the tiny bit of space in between and there is stuff passing between it."

Generations of Stars and Observing the Past

[44:45] Paul Mercurio:
Manaid Shandagai from North Wales asks, "If our son is a third generation star, how is it that we can observe earlier generation stars when looking back in time?"

[46:04] Neil deGrasse Tyson:
Neil clarifies that observing distant stars is akin to looking back in time. He explains that we can see first-generation stars because their light is only now reaching us, despite them having contributed to the elements that make up later generations.

[48:05] Charles Liu:
Charles emphasizes that while we are composed of elements from earlier stars, many first-generation stars still exist and can be observed, reinforcing the concept of looking back in time through light.

Notable Quote:
Neil deGrasse Tyson [46:04]: "As we look out in space, we look back in time and see the universe not as it is, but as it once was."

Mass, Time, and Relativity

[49:38] Paul Mercurio:
Manaid requests, "Given the relationship between speed and time, and the relationship between speed and mass, is there also, therefore, a direct relationship between time and mass? If time were somehow to stop, would everything become infinitely massive?"

[50:18] Paul Mercurio:
Paul humorously interjects, reflecting on the complexity of the question, while Charles attempts to address the theoretical implications.

[50:35] Charles Liu:
Charles explains that manipulating time in such a way isn't feasible within our current understanding of physics, highlighting the intricate relationship between time, space, and mass.

[51:50] Neil deGrasse Tyson:
Neil philosophizes on the nature of time, stating, “We are prisoners of the present, forever transitioning between our inaccessible past and our unknowable future,” underscoring the enigmatic essence of time.

Notable Quote:
Neil deGrasse Tyson [51:50]: "We are prisoners of the present, forever transitioning between our inaccessible past and our unknowable future."

Conclusion and Final Thoughts

As the episode wraps up, Charles Liu shares about his recent publication, The Handy Quantum Physics Answer Book, aimed at making quantum mechanics accessible to all. Paul Mercurio promotes his upcoming Broadway show, highlighting the collaborative and entertaining nature of the StarTalk team.

[54:44] Charles Liu:
Charles introduces his book, emphasizing the need for accessible scientific knowledge: “Quantum feels scary, it feels unknown. But actually, we interact with it every day.”

[54:52] Paul Mercurio:
Paul humorously discusses his involvement in the show and his upcoming performances, blending science with pop culture seamlessly.

Final Notable Quote:
Neil deGrasse Tyson [55:27]: "This has been a StarTalk. Cosmic queries. Grab bag. That was definitely some bag grabbing right there. All right, until next time, Neil deGrasse Tyson bidding you all to keep looking up."

---

Key Takeaways:

• Diffusion in Space: Unlike Earth, space allows gas clouds to form stable structures due to minimal dispersive forces and strong gravitational effects.
• Gravitational Waves: These ripples in spacetime offer profound insights into cosmic events and the fundamental structure of the universe.
• The Big Bang: A term that denotes the expansion of the universe from a hot, dense state, not an explosion.
• Cosmic Inflation and Galactic Interactions: Explores the rapid expansion phase of the universe and how galaxies influence each other without direct collisions.
• Generations of Stars: Understanding how we can observe ancient stars while acknowledging that elements from previous generations persist in newer stars.
• Time and Mass in Relativity: Delving into the complex relationship between time, speed, and mass, and the theoretical limits of manipulating time.

---

This episode masterfully blends scientific explanations with humor and relatable analogies, making complex astronomical concepts accessible and engaging for all listeners. Whether you're a seasoned science enthusiast or a curious newcomer, Neil deGrasse Tyson and his co-hosts offer a captivating journey through the cosmos.

Transcript

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[Neil DeGrasse Tyson]

So Paul, those are some fun questions in the cosmic craze grab bag.

[Paul Mercurio]

And from all over the world. All over the world. You know what? I think what people are gonna see in the upcoming episode is that we pretty obliterate time.

[Neil DeGrasse Tyson]

Time.

[Charles Liu]

Smoosh it.

[Neil DeGrasse Tyson]

Time succumbs to our logic and rational thought. Coming up on StarTalk. Welcome to StarTalk. Your place in the universe where science and pop culture collide begins right now. This is StarTalk. Neil DeGrasse Tyson, your personal astrophysicist I got with me as co host today, Paul Mercurio. Paul, welcome back.

[Paul Mercurio]

Thanks. Thanks for having me. Great to be back with you, buddy. Yeah.

[Neil DeGrasse Tyson]

This is the attorney, stockbroker turned comedian.

[Paul Mercurio]

Yes, attorney, investment bank, returned comedian.

[Neil DeGrasse Tyson]

There's nothing funny about lawyers and stockbrokers.

[Paul Mercurio]

No, exactly.

[Neil DeGrasse Tyson]

Okay.

[Paul Mercurio]

I found a way to like run from it as Fast as I can.

[Neil DeGrasse Tyson]

All right. So, Paul, we're gonna do grab bag cosmic queries.

[Paul Mercurio]

We are. We got some great queries here.

[Neil DeGrasse Tyson]

And I don't trust myself in grab bag mode. Yeah, I need backup.

[Paul Mercurio]

Yes, you do.

[Neil DeGrasse Tyson]

I gotta go for the big guy.

[Paul Mercurio]

You need your Starsky. You're.

[Neil DeGrasse Tyson]

Starsky and Scotch. Yeah. Wait, you have 70 to get that reference.

[Paul Mercurio]

He did pull up in a Ford Torino.

[Neil DeGrasse Tyson]

Charles Liu, welcome back to Star Talk.

[Charles Liu]

Hi, Neil. It's great to be back.

[Neil DeGrasse Tyson]

Charles. Longtime friend. Our families are friends and we're colleagues, yes. You were here when built the new Rose center for Earth and space 25 years ago.

[Charles Liu]

Has it been that long?

[Neil DeGrasse Tyson]

It's been a quarter century.

[Charles Liu]

Jeez, it feels like yesterday that I came over here and this place was a hole in the ground.

[Neil DeGrasse Tyson]

Yeah, it does feel that way. And it was. You have intellectual and sweat equity in what we built here, so we're thankful for that.

[Charles Liu]

Ah, it was fun.

[Paul Mercurio]

And that's weird because when we were talking, he wasn't here. You said he didn't do much. You took a lot of the credit.

[Charles Liu]

Well, you know, he's not wrong. I mean, I was just hanging out here all night, having a great time. Yeah. Yeah. That's all it was.

[Paul Mercurio]

Just jump right in.

[Neil DeGrasse Tyson]

Okay. All right, let's do it.

[Paul Mercurio]

This is from Galaxy. Hey, Dr. Tyson. Dr. Lou.

[Neil DeGrasse Tyson]

But Galaxy is the person.

[Paul Mercurio]

Yeah, Galaxy.

[Neil DeGrasse Tyson]

Galaxy.

[Paul Mercurio]

Okay, that's there. I am Brian from Roseville, California. I just recently joined the Patreon and I'm excited to have my question answered.

[Neil DeGrasse Tyson]

Welcome.

[Paul Mercurio]

Yes, thank you.

[Neil DeGrasse Tyson]

I say it right. Welcome to the universe.

[Paul Mercurio]

We dim the lights when you do that. I have always wondered how giant gas clouds and nebula exist in space. Shouldn't the vacuum cause all gas to disperse evenly to the point of not being. Even being able to see it?

[Neil DeGrasse Tyson]

I love that. Because on Earth, any cloud of gas disperses.

[Charles Liu]

That's right.

[Neil DeGrasse Tyson]

As dogs know.

[Charles Liu]

That's right.

[Neil DeGrasse Tyson]

Dogs will smell you from far away because whatever is your stank.

[Paul Mercurio]

One minute in, because the guest has stank. This is a lesson anybody wants touching on how not to host a show.

[Charles Liu]

At least it's not Smell O vision. Goodness gracious.

[Neil DeGrasse Tyson]

Yeah. So it does dissipate.

[Charles Liu]

It's a great question.

[Neil DeGrasse Tyson]

You look at blood in the water and that.

[Paul Mercurio]

Does it dissipate evenly?

[Neil DeGrasse Tyson]

Well, it's a diffusion equation where you have molecules. It wouldn't happen in solid because all the molecules are just rigid. But in a fluid, they can vibrate. No, but you're not gonna move it through the system.

[Charles Liu]

There's a phase issue.

[Neil DeGrasse Tyson]

I'm saying it's not going to move through the system.

[Charles Liu]

Just trying to get technical.

[Neil DeGrasse Tyson]

Okay.

[Paul Mercurio]

And wow, this is getting tense already.

[Charles Liu]

Well, he called me skank. I mean, what am I supposed to do?

[Neil DeGrasse Tyson]

I didn't say skank. You know what?

[Charles Liu]

We don't need this.

[Paul Mercurio]

We'll do our own show.

[Charles Liu]

There we go.

[Neil DeGrasse Tyson]

Okay, Paul, get out of here. So the diffusion equates. So you have a molecule that can move like all the others and it just works its way through. In my high school there was a diffusion experiment where they. It's a long tube. It was one of these display. Cause we didn't have any athletic trophies to put to a geeky high school. So you gotta put other stuff in your hallway display cases.

[Paul Mercurio]

This a hall of beakers, is that right?

[Neil DeGrasse Tyson]

Yeah. One of it was a very tall beaker. Yes, about this tall, if I remember correctly. That was littler. Not much littler, but I think it was this big. And there was ink at the bottom.

[Charles Liu]

Ah, yes.

[Neil DeGrasse Tyson]

And they carefully put water on top of it. And throughout the year you got to watch. Cause the ink is slightly denser, but still they're both fluids. And so you get to watch the ink work its way up real slowly.

[Charles Liu]

Yeah. At my high school they had diffusion experiments every afternoon after the school lunches were served bean soup.

[Neil DeGrasse Tyson]

Oh.

[Charles Liu]

And in every classroom there would be experiment of different particles suspended in the atmosphere, moving from one side of the classroom to the other. After you first heard, heard that something was.

[Neil DeGrasse Tyson]

People didn't figure out to not eat the bean soup.

[Paul Mercurio]

Right, Exactly. And that's where you got your name. Skank.

[Charles Liu]

Stank, stank, stank, stank.

[Paul Mercurio]

So did you. But could you do that same with the ink? Could you do it with oil like cooking oil or olive oil?

[Neil DeGrasse Tyson]

Would it work harder? No, because oil would float. And the miscibility between oil and water is very different between. Because ink is, has, is. Most inks that we use today are water based anyway. So the water is finding the water molecules.

[Charles Liu]

Yeah. So Brian, the answer is basically the conditions out in space make it so that these gas particles tend to disperse unless they have a reason to collect. Okay. Here on Earth you have different kinds of things like buoyancy involved and things like that. That also happens in space. But in space, when the temperatures are very low, say 400 degrees below zero Fahrenheit, gravity can actually overcome a lot of the motional sort of dispersive diffuses.

[Neil DeGrasse Tyson]

Emotional.

[Charles Liu]

Emotional. Emotional, yes, it could be emotional.

[Neil DeGrasse Tyson]

You know, I ain't Doing this.

[Paul Mercurio]

It's very moving.

[Charles Liu]

That's right.

[Paul Mercurio]

You tear up, you start crying.

[Neil DeGrasse Tyson]

Emotional. I never heard that word.

[Charles Liu]

To be a star. Oh, my gosh.

[Neil DeGrasse Tyson]

Yeah, yeah. So some gas stars.

[Charles Liu]

Yeah, yeah. When it's cold, the random motions of the gases are actually overcome by the mutual gravity that they exert on each other.

[Paul Mercurio]

Does it happen? Is it dispersing in an. In an even nature? Not evenly.

[Charles Liu]

Everything is turbulent. If you go see, for example, beautiful pictures of, say, the Orion Nebula or other interstellar clouds, you see that they're streaky and strange and unusual shape. They look like horse head. They look like helixes and cat's eyes and things like that. And that's completely because the turbulence is still going on.

[Paul Mercurio]

Is it that you're smoking something funny?

[Medical Disclaimer Voice]

That too.

[Neil DeGrasse Tyson]

You know, both Merc.

[Charles Liu]

We got to ask, these stars that are emitting their planetary nebulae, what are they smoking? You know, I think that would be a very, very good idea. But the bottom line is that in space, you have gravity holding these clouds together long enough for them to do things like form stars and planets. But there's always these forces and these different energies and so forth for trying to disperse them. And so you get beautiful combinations, and that's why you get beautiful nebulae and you get things like stars and planets.

[Neil DeGrasse Tyson]

I will add that you have a gas cloud that makes a family of stars. So that eats up most of the mass of the gas cloud. But there's part of the gas that didn't participate in the formation of the planet.

[Paul Mercurio]

A little snooty, like you were in high school. Little snooty, little standoffish.

[Neil DeGrasse Tyson]

It just wasn't. And that gas doesn't always land on a star.

[Paul Mercurio]

Do we know why? In all seriousness.

[Neil DeGrasse Tyson]

Well, now the gas doesn't have enough gravity to make it a next star. We're done.

[Paul Mercurio]

No, but at the time, and I'm not trying to be funny, it's too far away. That gas. I got this, like all the other gases had an equal opportunity part of that.

[Neil DeGrasse Tyson]

It's not an equal opportunity system. If you're a little too far away, you might not feel the strong enough gravity to participate. And the stars form without you. And then the whole galaxy is rotating, okay? So your whole system with your stars and your gas is moving, and there's other stuff. So your gas can get stripped and scatter into the galaxy, never to make another star.

[Paul Mercurio]

So that gas just continues as gas throughout the universe.

[Neil DeGrasse Tyson]

And these are the particles that comprise the interstellar medium even between the gas clouds. It's not completely empty.

[Paul Mercurio]

Okay.

[Neil DeGrasse Tyson]

Yeah.

[Paul Mercurio]

And can that gas marry with other gases eventually and sort of possibly be part of another?

[Charles Liu]

It depends completely on, like, what Neil was saying. What is the rotational shear? What is the temperature in the environment? How much of it just happens to gather at this moment, whether it can actually collect or not collect. It's really beautiful and fascinating. But the funny thing is, it is very, very sparse. Right here on Earth, we have trillions upon trillions of particles of gas, even in the tiniest beaker or vial. But out in space, just even a couple hundred miles above Earth's surface, we're lucky if we even get one gas particle.

[Neil DeGrasse Tyson]

It'd be the best vacuum ever created on Earth.

[Charles Liu]

Yeah.

[Neil DeGrasse Tyson]

Is what just space?

[Charles Liu]

So people who study interstellar clouds are literally studying nothing.

[Paul Mercurio]

Yeah.

[Charles Liu]

And yet that's the nothing from which we come from.

[Paul Mercurio]

Right. So it's endlessly fascinating.

[Charles Liu]

Yeah.

[Neil DeGrasse Tyson]

Such is the layout of this cosmic ballet.

[Paul Mercurio]

Well said.

[Neil DeGrasse Tyson]

Choreographed by the forces of gravity.

[Charles Liu]

It's more like a Martha Graham kind of ballet. Makes it too orderly.

[Paul Mercurio]

I'm feeling Alvin Ailey.

[Charles Liu]

Okay.

[Neil DeGrasse Tyson]

Yeah, we go. Alvin Ailey.

[Charles Liu]

I've been buked.

[Neil DeGrasse Tyson]

Wins every time.

[Paul Mercurio]

All right, we're moving on. Great question, great answers. Christopher Wynn. Hello, Dr. Sykes and Dr. Liu. I am Chris Wynn from Ottawa, Ontario, Canada. I'm new to preaching, and I love your show. My question is, during the Big Bang, what went bang? If we don't know, what are your best guesses?

[Neil DeGrasse Tyson]

There's only one answer here. It's the universe went bang.

[Medical Disclaimer Voice]

Right.

[Neil DeGrasse Tyson]

Okay, next question.

[Charles Liu]

I could take.

[Paul Mercurio]

Well, we know the idea. We know the idea of personal space was blown. Right.

[Charles Liu]

Look, the term Big Bang was actually coined by or attributed.

[Paul Mercurio]

It's so misleading because it's about expansion, not about bang.

[Charles Liu]

It's attributing.

[Paul Mercurio]

And why don't you guys fix that?

[Charles Liu]

I've tried.

[Neil DeGrasse Tyson]

There's a lot of legacy language that permeates our field, and it makes it historically interesting.

[Paul Mercurio]

Can I ask a question? No. In all seriousness, how would that process work? Work within the scientific community if you wanted to sort of take on the task of changing?

[Charles Liu]

Oh, you mean like, if you change Pluto?

[Neil DeGrasse Tyson]

Don't even say, stop it. I'll kick you out of this office and throw you off the roof.

[Paul Mercurio]

No, say it.

[Charles Liu]

I'm already stank. So, I mean, why not?

[Paul Mercurio]

Come on. Stank.

[Charles Liu]

No, no, no.

[Neil DeGrasse Tyson]

Wait. No, no, go ahead. Two very important points here. So finish your Big Bang story.

[Charles Liu]

Okay. The Big Bang term is attributed to a guy named Fred Hoyle. It was an interview done early on in the middle of the 20th century.

[Neil DeGrasse Tyson]

Back when ideas for the beginning of the universe were still uncertain and they were still contesting.

[Charles Liu]

Right. And so he himself did not like the idea that the universe started from nothing or something very small and became something big. And so the journalist that he was speaking with or interviewer or whatever says something like, so you're thinking of the universe as kind of like a big bang of some kind. And that just stuck.

[Paul Mercurio]

Did he do it to make science, in all seriousness, sexy? Like sort of to get people to sort of understand?

[Charles Liu]

Today, no one really knows. I've seen it historically expressed as it was derisive or that it was spectacular, one or the other. But yes, the right answer is it's an expansion of space and time from something small to something big. It was not an explosion. And now we have this problem where we think, oh, if the Big Bang is an explosion, what did it explode into? You know, things like that.

[Paul Mercurio]

Well, a key part of that.

[Neil DeGrasse Tyson]

Where did it explode from? Yeah, there's a lot of other.

[Paul Mercurio]

And then there's this thing called. This is cosmic inflation.

[Charles Liu]

That's right.

[Paul Mercurio]

Which. Which happened in the first tiny fraction.

[Charles Liu]

Of a second, which is an expansion within an expansion. You know, imagine if you're blowing up a balloon slowly, and then suddenly someone slaps you on the back and your air all goes out at once and it blows up. And we call that inflation, which gets mixed in with all kinds of other.

[Neil DeGrasse Tyson]

During the Jimmy Carter era, hyperinflation that.

[Charles Liu]

Existed at the door just before Nixonian times.

[Neil DeGrasse Tyson]

Are you sure?

[Paul Mercurio]

But there is a thing.

[Neil DeGrasse Tyson]

But it was like it was in.

[Charles Liu]

The 70s, but there is a 7 inflation.

[Paul Mercurio]

When this happened. Okay. Cosmic inflation. There is a theory that a gas cloud formed the initials WIN which is WHIP inflation. Now Jimmy Carter. Come on. That was good.

[Neil DeGrasse Tyson]

Okay.

[Paul Mercurio]

See how I brought that back?

[Charles Liu]

It's historical, though. Yeah, right. Oh, by the way, everything is historical.

[Neil DeGrasse Tyson]

Just while we're on the. How does it relate back to society? I came of age. I'm a little older than you. I came of age.

[Charles Liu]

You're a lot older than me.

[Neil DeGrasse Tyson]

When people.

[Paul Mercurio]

I think I heard him whisper your oldest dirt. I didn't think it was a very scientific term, but that's what he used.

[Neil DeGrasse Tyson]

I think I'm 20% older than Charles here, plus or minus. So I came of age when we applied computing power to what galaxies would do to each other when they encountered.

[Charles Liu]

Classic paper by two brothers, Alar and Yuri Toomre in 1972.

[Neil DeGrasse Tyson]

Tombre and Tombray Yes.

[Charles Liu]

Terrific paper.

[Paul Mercurio]

What kind of data are you inputting into the.

[Neil DeGrasse Tyson]

So you. We saw these weird looking galaxies out there. This is just an analog, so I don't wanna spend too much time on it. Really weird looking galaxies. And there was someone in our field who compiled them into one catalog chiparp called the Atlas of Peculiar Galaxies. Yeah, these are galaxies. They're just weird. They don't match any form. So I don't know why, but here they are. And everyone's saying, what could make these galaxies? Are they born that way? And then Gerard de Vaucouleurs, who was at Galaxy Jerry, I call him Jerry.

[Paul Mercurio]

Yeah, we're like this.

[Neil DeGrasse Tyson]

He. He was very French.

[Paul Mercurio]

He very.

[Neil DeGrasse Tyson]

He was pretty sure that a crashed Lexus is not a different kind of car. It's still a Lexus. Okay, so he. That was.

[Charles Liu]

He becomes a Toyota.

[Neil DeGrasse Tyson]

Actually.

[Charles Liu]

Yeah.

[Neil DeGrasse Tyson]

So he.

[Charles Liu]

Sorry.

[Neil DeGrasse Tyson]

Becomes a Toyota. Good one, good one. So the idea that. No, they're not peculiar. They changed because they had these encounters, these collisions.

[Paul Mercurio]

These galaxies collide.

[Neil DeGrasse Tyson]

Yes. And they're colliding all the time.

[Paul Mercurio]

Right.

[Neil DeGrasse Tyson]

Okay, now I forgot why I was even gonna mention cosmic inflation. Where was I gonna do non inflation? Oh, yeah, yeah. At the time. At the time. This is now in the 80s. Okay. This is your people now. In the 80s. We called this.

[Paul Mercurio]

Wait a minute.

[Neil DeGrasse Tyson]

No, no. You'll understand why in 10 seconds.

[Charles Liu]

Come on, Eileen.

[Neil DeGrasse Tyson]

So we called it in our field, mergers and acquisitions.

[Paul Mercurio]

Oh, my God, we did. Are you serious? I have no idea.

[Neil DeGrasse Tyson]

Galaxy mergers and.

[Paul Mercurio]

Oh my God, it was so hot.

[Neil DeGrasse Tyson]

Then it was so hot right out of Wall Street. So we have inflation and mergers and.

[Paul Mercurio]

Acquisitions and now look where we are.

[Charles Liu]

That's right, we were.

[Paul Mercurio]

Dr. Stank.

[Patient]

I won't let my moderate to severe plaque psoriasis symptoms define me.

[Pharmaceutical Representative]

Emerge as you. In two clinical studies, Trimfaia Gu glucumab, taken by injection provided 90% clearer skin at 16 weeks in 7 out of 10 adults with moderate to severe plaque psoriasis. In a study, nearly 7 out of 10 patients with 90% clearer skin at 16 weeks were still clearer at 5 years. At 1 year and thereafter, patients and healthcare providers knew that tremphya was being used. This may have increased results. Results may vary.

[Medical Disclaimer Voice]

Serious allergic reactions may occur. Tremphya may increase your risk of infections and lower your ability to fight them. Before treatment, your doctor should check you for infections and tuberculosis. Tell your doctor if you have an infection or symptoms of infection, including fever, sweats, chills, muscle aches or cough. Tell your doctor if you had a vaccine or plan to emerge.

[Pharmaceutical Representative]

As you learn more about Tremphya, including important safety [e-mail] or call 1-877-578-3527. See our ad in Food and Wine magazine. For patients prescribed Tremphia, cost support may be available.

[Paul Mercurio]

Wow. What's up?

[Charles Liu]

I just bought and financed a car.

[Neil DeGrasse Tyson]

Through Carvana in minutes.

[Pharmaceutical Representative]

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[Neil DeGrasse Tyson]

They made it easy, Transparent terms, customizable, down and monthly. Didn't even have to do any paperwork.

[Pharmaceutical Representative]

Wow.

[Neil DeGrasse Tyson]

Mm. Hey, have you checked out that spreadsheet I sent you for our dinner?

[Charles Liu]

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[Pharmaceutical Representative]

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[Charles Liu]

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[Neil DeGrasse Tyson]

Hello, I'm.

[Medical Disclaimer Voice]

Alexander Harvey and I support StarTalk on Patreon. This is StarTalk with Dr. Neil DeGrasse Tyson.

[Paul Mercurio]

The big Bang within the bang. Big bang at the tiny fraction of that moment when it happened.

[Charles Liu]

Yep.

[Paul Mercurio]

Is there still yet an explanation as to why that had happened?

[Charles Liu]

There are numerous competing hypotheses, but we don't have the experimental evidence to show the initial burst or the thing that caused it to happen. We're pretty sure it did happen and.

[Neil DeGrasse Tyson]

We got lots of that information. The bigger part is our particle accelerator. The earlier in time it can see, not see, but represent in the temperature density. In the particle accelerator, you can say in the first microsecond or the first nanosecond of the universe, what was the temperature? Oh, my gosh, it was this high. Have we ever reached that temperature in the lab? No, not yet. The day we do, we get to say we think we have sampled what the early universe would have looked like. Do new particles pop in? Is there a dark matter particle that shows up? We don't know.

[Paul Mercurio]

But do you both understand this brilliant scientist that lay people like myself are looking for in all seriously solid answers?

[Charles Liu]

Right?

[Paul Mercurio]

Like, I'm. I'm still trying to figure myself out. Hang on a second. Figure myself out through counseling, therapy, Whatever. The universe hasn't been able to figure itself out in 13.8 billion years. Can you guys get on the stick.

[Neil DeGrasse Tyson]

And give us an answer here?

[Charles Liu]

I would like to. I would like to, but this is the. You. You hit the key point in the difference between. Yes. You've hit the key point between what I think is the difference between scientific truth and non scientific truth. With scientific truth, we always put in the but maybe we're wrong part that we don't know for absolute sure part. And that's really, really important. Right. Science could not have progressed if somebody said this is the right answer. And then everyone just, oh, okay, okay.

[Paul Mercurio]

People would have stopped snoring.

[Charles Liu]

It's incredibly important to recognize that we have ignorance. Neil has a terrific term for this, the perimeter of ignorance. We have to understand that there's a space beyond which we don't know the answer yet, or even what we think we know could be wrong because of this, this, this, this, and this.

[Neil DeGrasse Tyson]

Which is why, Paul, you need to love the questions themselves. Oh, in your search for questions.

[Charles Liu]

That is too profound, dude. Too profound.

[Neil DeGrasse Tyson]

No, that's Rainer Maria Rilke in a poem. Yes. Plus, I have to adjust where. What he just told you Here. Okay.

[Charles Liu]

Like a chiropractor, he's gonna.

[Paul Mercurio]

He's gonna adjust.

[Neil DeGrasse Tyson]

Wrong word. I need a different word.

[Paul Mercurio]

He's gonna straighten your mental back out. Crap your mental vertebrae.

[Neil DeGrasse Tyson]

Yeah. So I put a lot of thought and energy into defining what true means. And I've settled in a way that I think is highly defensible and should be adopted. Okay.

[Charles Liu]

Okay.

[Neil DeGrasse Tyson]

So scientific truth is that which has been established by repeated observations and measurements. When that happens, it is not later shown to be false. So we can talk about it as an objective truth. E mc2 is not one day gonna be found to be false. That Earth goes around the sun, that the sun is hot, that the sun undergoes thermonuclear fusion is not gonna one day be found to be false. Where Charles is referring to. We have to have some acceptance that we could be wrong. Yes.

[Paul Mercurio]

About things that we are not definitively correct.

[Neil DeGrasse Tyson]

On the frontier, we're wrong most of the time.

[Paul Mercurio]

But There are some.

[Pharmaceutical Representative]

90%. 90%.

[Paul Mercurio]

There are some things that we've reached. At least the community is comfortable saying, you're saying that there are some things equals MC squared, et cetera. Where we're not questioning that anymore.

[Neil DeGrasse Tyson]

The huge things, huge swaths.

[Paul Mercurio]

Otherwise you can't do.

[Neil DeGrasse Tyson]

Otherwise we're not flying airplanes.

[Paul Mercurio]

Otherwise you can't do the exploration into the things we can do.

[Neil DeGrasse Tyson]

Airplanes wouldn't fly. Rockets don't go to Mars and land exactly where we tell them.

[Paul Mercurio]

They put this in your research, that there's another rationale. But I think what you're saying is.

[Neil DeGrasse Tyson]

No, no, no, hold on, let me finish. I'm almost done. Okay? It doesn't mean that we will not one day find a deeper truth in which the experimentally verified truths are embedded. Such was the case with Newton's laws of gravity and motion. Those laws in the realms in which they were tested are still valid. We went to the moon using Newton's laws and not Einstein. Okay? There was no relativity in the Apollo voyages. It was all Newton's laws of gravity and motion. We then learned that at high speeds, high gravity, Newton's laws break down. Holy shit. Do we discard Newton? What's going on?

[Paul Mercurio]

Well, there's gravitational waves.

[Neil DeGrasse Tyson]

So Einstein finds a deeper understanding of gravity and motion and he gets his theories of relativity, the special theory in general relativity. Guess what? When you plug low speeds and low gravity into Einstein's equations, they become Newton's equations. People say, oh, he's Newton out. Einstein in that misrepresents what's actually happening here.

[Paul Mercurio]

Well, they co. You can't have. It's chicken egg. You can't have one without the.

[Neil DeGrasse Tyson]

Well, no, I mean in terms of the pathways of discovery. You get the restricted case before you discover the general case. My only point is the uncertainty that a scientist brings to the frontier is in the realm of things that we have not yet experimentally verified. And it's completely uncertain at that level. And we're just duking it out at conferences and the like. And the press eavesdrops on the conferences. They say, oh, scientists don't know what they're talking about. And then people say, I don't trust science. Yeah, yeah. As they're on their smartphone talking to someone a thousand miles away. I don't trust science. You know, So I just wanna clarify that and two other truths. There's your personal truth. Like, is Jesus your savior? Is Muhammad your last prophet? Is Beyonce your queen, rather than Taylor Swift? Right. So that's a personal truth. Then you have political truths, which are things that become true in your head simply because they were repeated so often. Which are the foundations of.

[Paul Mercurio]

Or because you read it on Twitter.

[Neil DeGrasse Tyson]

How many times you read it? It's how many times. And so is that any different?

[Paul Mercurio]

Is that any different than commercial advertising? No, exactly the same thing. You're going to show you this Toyota 50 times. And by the end of the week, you're going to be like, I got to get a Toyota.

[Neil DeGrasse Tyson]

That's a great car. And no matter what they're telling you, that becomes true. So those are the three truths. And I will never speak of an absolute truth because that's not what science does.

[Charles Liu]

Newton's gravity was proven to be wrong. Is true. It was wrong because in certain conditions in the universe, it was not correct.

[Paul Mercurio]

But that's an. I don't mean.

[Neil DeGrasse Tyson]

But those are extreme conditions, well beyond.

[Paul Mercurio]

The experimental realm that expands our knowledge. It's a good thing when a bad thing happened like that. It's a good thing because it expands our basic knowledge.

[Neil DeGrasse Tyson]

And we don't call it bad. We don't invest emotions in it.

[Charles Liu]

Does it?

[Neil DeGrasse Tyson]

Some people do, but. But it's not good if you do, right?

[Paul Mercurio]

Well, I talk like a six year old.

[Charles Liu]

So do I.

[Paul Mercurio]

Well, this is perfect because this next question is about gravitational waves.

[Charles Liu]

Love it.

[Paul Mercurio]

I'm telling you. This is eerie. Okay, this is Mitchell Ransom. Mitch from the uk. I would love to know more about what we can learn from gravitational waves. It's cool. We can detect them, but what can that do for our understanding of the universe?

[Charles Liu]

Marvelous question.

[Paul Mercurio]

Purpose. That's perfect.

[Charles Liu]

Marvelous question.

[Neil DeGrasse Tyson]

You take this. I'll back cleanup on it. Okay, go.

[Charles Liu]

I will be the one somewhere in the one Ohtani.

[Paul Mercurio]

And then I'll be the guy who shouldn't steal second and does and gets thrown out and ruins the inning.

[Charles Liu]

Well, if Ohtani were stealing, he'd actually make it.

[Paul Mercurio]

Oh, my God.

[Neil DeGrasse Tyson]

Or if you're going to steal second, do it deep into the count of a batter you want to see come up again the next inning.

[Paul Mercurio]

That's true.

[Neil DeGrasse Tyson]

Right. Because they get fresh.

[Paul Mercurio]

Right.

[Charles Liu]

And also fundamental baseball, which doesn't get. Get talked about nearly as much as.

[Neil DeGrasse Tyson]

We should do a whole thing on baseball.

[Paul Mercurio]

Oh, my God.

[Neil DeGrasse Tyson]

Oh, my gosh.

[Paul Mercurio]

It's the biggest. I mean, I, I think the pitch clock, while it's helped speed the game up, I mean, stealing is so much more interesting and fun to watch because you go over there twice, you know you're going to get. You, you got, you can. You can't go back at that time.

[Charles Liu]

That's right. So they're very interesting. Rules are always fun, too. Talking about rules, the most interesting sport.

[Paul Mercurio]

To watch, I think baseball because of all of the machinations. But anyway.

[Charles Liu]

Yeah. Okay, well, here's the deal. Gravitational waves are essentially to the universe and space and time as, say, ripples are in a pond. Right. So if you see ripples Going on in a pond or any body of water, you can deduce things about that pond. What is the water made out of? Is there duckweed on the top? How deep is it? Is there ice? You know, things like that. All the different things about that puddle.

[Neil DeGrasse Tyson]

By the way, the depth affects the amplitude of the ripple completely. Right. So it's. Why, when you're at the beach, how come, you know, you see a swell sort of out there, but then it gets closer to the shore, it becomes a big wave. So the energy that is out there in the ocean, which is shared vertically to the bottom of the thing, as you get shallower and shallower, that energy has to manifest somehow. And the height of the wave grows. And so the energy is the same, but the height and how you experience it as a beachgoer.

[Paul Mercurio]

But where does wind come into this? If I'm. Because wind can create a wind ripple.

[Charles Liu]

It can also come into.

[Paul Mercurio]

This doesn't have to just come.

[Charles Liu]

That's right. The top has an effect, the bottom has an effect, and the side has an effect. Right. Where is it coming from?

[Paul Mercurio]

In other words, it's bouncing off the side.

[Charles Liu]

The edges make a difference if you're in a bay or if you're just hitting a wide shoreline. Also, what is the material of the beach? Is it rocky? Is it sandy? So gravitational waves literally have the opportunity, if we're sensitive enough to detect them, to tell us about spacetime, the structure of the universe, the things that these ripples go through.

[Neil DeGrasse Tyson]

Gotta add real quick, Charles is talking about things you would know beyond just the simple detection of the wave.

[Charles Liu]

That's right.

[Neil DeGrasse Tyson]

It's one thing to know that there's a wave there. Now, what's the amplitude? What's the wavelength? How many of these are there? Are they coming from this direction? There's different layers. But the Nobel Prize went to basically the first time it was ever discovered. And then you can keep asking more detailed questions when your telescopes become better to do so.

[Charles Liu]

That's right.

[Paul Mercurio]

But this gets to Newton's law of universal gravitation. Right. Which does not provide for the existence of gravitational waves. It asserts that gravity has instantaneous effect, which is wrong because I dropped a 1982 bottle of Chateau Lafitte Rothschild and it fell in slow.

[Neil DeGrasse Tyson]

Did you seriously do that?

[Paul Mercurio]

In slow motion?

[Neil DeGrasse Tyson]

Did you seriously do that?

[Charles Liu]

It landed on a pillow, I'm sure.

[Paul Mercurio]

And it fell in slow motion. Everything slowed down. So Newton's wrong.

[Charles Liu]

I'm right.

[Paul Mercurio]

No, but. So now. So that's where Newton and Einstein. Right. Are Sort of.

[Neil DeGrasse Tyson]

No, wait, wait. Just to be clear, Newton Nixon did not have a strong investment in any expectation that things happened instantaneously. His big concern was that it was action at a distance and there was nothing in between. That was just a little weird. He knew it worked, but he couldn't explain it in any way. But he was not deeply invested.

[Paul Mercurio]

Put an example of that for that, for me. So there's something in the distance, but nothing in between.

[Charles Liu]

But let's say I turn off that light over there. It actually takes a fraction of a second for that light material for that information to get to me that the light is no longer shining.

[Neil DeGrasse Tyson]

Except for Muhammad Ali, who, you know what he said? He said, I'm so fast, I could turn out the lights and be in bed before it's dark.

[Charles Liu]

He also floated like a butterfly and stung like a bee. That guy was pretty amazing.

[Neil DeGrasse Tyson]

Yeah.

[Charles Liu]

So that speed at which that light and that dark travels to my. Is so fast that I as a human being could never detect it. But if I had a very sensitive camera, that could really stop down time to billionths of a second or trillionths of a second at a time. You can actually see it getting darker as it moves forward to your eye.

[Neil DeGrasse Tyson]

So light moves 1 foot per nanosecond per billionths of a second. So you just need billionths and you can catch. Catch.

[Charles Liu]

Yeah.

[Neil DeGrasse Tyson]

So it's from the side. If you look at it from the.

[Paul Mercurio]

Side, you would literally see it right now. There's a straight white line of light. And then you'd see it getting darker, darker, darker.

[Charles Liu]

Well, there's also background light. Right. Remember, our light is primarily illuminating from.

[Neil DeGrasse Tyson]

If you have a laser and put chalk dust in there and you see it through and then you do this.

[Charles Liu]

That would work. That would be a great way to do that. Absolutely.

[Neil DeGrasse Tyson]

But people don't know what chalk dust is.

[Paul Mercurio]

Go to a baseball game, you'll see. There you go.

[Neil DeGrasse Tyson]

Oh, yeah, yeah.

[Charles Liu]

For the so new tickets, Newton really didn't get the sense or understand that there was a time lag. Right.

[Paul Mercurio]

Einstein, which is what gravitational waves all about.

[Charles Liu]

Right, Right.

[Neil DeGrasse Tyson]

Well, they move at a speed.

[Charles Liu]

Einstein showed that information in the universe, especially carried by light. Right. And waves, has a speed limit. And then folks wondered and it's not.

[Neil DeGrasse Tyson]

Just a good idea, it's the law.

[Charles Liu]

It's a great commercial dad joke.

[Paul Mercurio]

What's going on in your brain?

[Neil DeGrasse Tyson]

It's a dad joke.

[Charles Liu]

I love the dad jokeness of that. It's really very good. So, so what happened is that Einstein showed that There was this reasonable sort of speed limit to the universe, the speed at which light travels in the vacuum. And then folks said, well, you know what? If that's the speed limit of light, maybe that's also the speed limit of these things, these other things. Any information at all, you know. And so, like gravity. Yeah. So maybe gravity only travels at the speed speed of light. And that's important to know. When we see gravitational waves, we infer the existence of little tiny particles called gravitons that travel through space in order to have this wave happen. We still have never detected the existence of gravitons in the laboratory. We may never be able to unless we can get a particle accelerator the size of the solar system. But what we can do is to say, well, this proves that speed of light and speed of gravitational waves and so forth are so close to one another that there's a. There must be something there. So that in itself, I guess, is another discovery. Right. By gravitational waves existing, you start putting strict upper limits on the mass of the graviton.

[Neil DeGrasse Tyson]

Just to be clear, before you know anything about photons of light, light was described as waves. And then we learn that. That the wave particle, you know, it can manifest as a particle, the photon, or as that you can detect, or as waves, which you can also detect as waves. By analogy to that, gravitational waves are granted a particle counterpart graviton.

[Paul Mercurio]

The graviton, which is a counterpart to the photon.

[Neil DeGrasse Tyson]

Correct. And you need different mechanisms to detect it in that mode.

[Paul Mercurio]

When we say particles collide to create virtual particles, do they really fist bump each other down at the Planck scale, occupying the same voxel at the same time? Or do they just get close enough and then, you know, magic happens?

[Charles Liu]

Great question. They get close enough. As an undergraduate, I learned some about a very technical, silly term called the impact parameter.

[Neil DeGrasse Tyson]

Love it.

[Charles Liu]

And that means that if you have two things coming toward each other, how close do they have to be before they impact each other? Affect each other?

[Paul Mercurio]

They don't have to touch each other.

[Charles Liu]

They don't actually have to touch.

[Paul Mercurio]

So, like, if I did this to you, right? I'm not touching you. I'm not touching you.

[Charles Liu]

He's not touching me. Stop touching me.

[Paul Mercurio]

I'm annoying.

[Neil DeGrasse Tyson]

Wait, let's go a layer deeper. We did a whole episode of Cosmos on this. Because of electromagnetic forces which hold your body together. When I go up to Charles and I touch him, if you actually analyze what's going on at the molecular and atomic level. I'm not actually touching him. There are forces in A field surrounding the particles and it's the forces that are bumping off each other. And this impact parameter exists when there are fields that surround the objects that are coming near each other.

[Paul Mercurio]

I can see my finger, my skin, touching that surface. So, so you're telling me that I'm.

[Charles Liu]

What I'm seeing at a very microscopic.

[Paul Mercurio]

Scale, there's something between that plastic and that surface.

[Charles Liu]

There is space between that plastic and your skin. But what happens is that the fields transfer energy. So your skin still feels as if it is physically touching something, but that's.

[Paul Mercurio]

Something coming from the bottle and the bottles coming from the skin.

[Charles Liu]

Right. So there is a tiny bit of space in between and there is stuff passing between it.

[Neil DeGrasse Tyson]

Otherwise your finger would just pass through the plastic.

[Paul Mercurio]

So there's a space like the plastic is perfect. Like my emotional relationship with my wife.

[Neil DeGrasse Tyson]

There's a liver we don't want to get into. So I'd love this, what Charles says, because we don't hear that term much, but it's kind of, it's almost self explanatory. It's the distance within which you can declare there was an interaction between the two objects.

[Paul Mercurio]

There's a way to measure that.

[Charles Liu]

You can put it in the mathematical equations and say, okay, well, I have some force field in my finger. You have some force field in that plastic container. When they come together, how close do they have to be before I feel the force of those container particles pushing on my finger? Particles?

[Neil DeGrasse Tyson]

It's more precise than that. So you have two. I'm pulling this out of my 30 year memory. 30, you can ask. Okay, 30. So if two objects, two gravitational objects that come by and one just gets pulled a little bit.

[Charles Liu]

That's right.

[Neil DeGrasse Tyson]

You can say, all right, what does that mean? But you can define, just for conversational and mathematical purposes, the impact parameters is the distance within which its trajectory will be altered by more than 90 degrees.

[Charles Liu]

It's pretty cool. So that's why when we talk about say colliding galaxies, the stars in the galaxies actually never hit each other, they never touch each other, almost never have direct collision passes through, but they go by each other. And as they go by, it's like a swarm of angry bees in fact.

[Paul Mercurio]

And they affect each other to the point where there can be an explosion.

[Charles Liu]

To the effect where at times you will have an explosion. That's right.

[Paul Mercurio]

So if I'm touching this, is there a force that's strong enough or can be measured at which I can push those magnetic field or those fields apart and I'm actually touching it. Is it ever possible to eliminate that field? That's between the thing my finger and the pen.

[Charles Liu]

Let's say it is almost never possible. Because there is a limit beyond which the math breaks down, you see, in the quantum structure of the universe.

[Paul Mercurio]

By the way, I feel like I'm asking to use the car and he's saying maybe, and my dad's saying, go ahead.

[Charles Liu]

No, sorry.

[Neil DeGrasse Tyson]

I just wanna back up for a minute.

[Charles Liu]

Keep it under 30 miles an hour. You'll be all right.

[Neil DeGrasse Tyson]

Back up. Just story time real quick.

[Paul Mercurio]

Okay?

[Neil DeGrasse Tyson]

Okay. I'll be reading from Merlin.

[Paul Mercurio]

Can you have some milk? Warm milk? Hot cocoa? Can I get some hot cocoa?

[Neil DeGrasse Tyson]

Alex Merlin's tour of the Universe. Dear Merlin, is there a chance that another star will one day collide with the sun? Yes, but you should know that if there were just four snails randomly carousing across the continental United States.

[Charles Liu]

Snails don't corral, do they? Snails.

[Paul Mercurio]

Crude, yes. What are they? Alcoholics?

[Charles Liu]

Hey, snail, how's it going?

[Paul Mercurio]

Drug addict.

[Neil DeGrasse Tyson]

It's more likely for two of them to accidentally bump into each other than it is for another star and the sun.

[Paul Mercurio]

Seriously to collide.

[Neil DeGrasse Tyson]

Yes. And then my artist brother drew two.

[Paul Mercurio]

Snails colliding here, one of which has a bandana and a gun. Really weird. It's a carousing. That's the carousing.

[Charles Liu]

There you go.

[Neil DeGrasse Tyson]

It's mostly empty space. So two galaxies collapse, the stars just pass through. But they definitely affect each other gravitationally.

[Paul Mercurio]

So if this, this star, this star's going by, it's it. There's enough. There is enough energy there that it can cause each to explode.

[Charles Liu]

Not necessarily. They'll cause each other to change their trajectories.

[Neil DeGrasse Tyson]

Got it.

[Charles Liu]

But once every four seconds or so in the whole observable universe, this is an estimate made a few years ago. There is actually a direct collision. Okay. This is most likely to happen in dense clusters of stars.

[Neil DeGrasse Tyson]

Very dense.

[Charles Liu]

Okay. Like globular clusters.

[Neil DeGrasse Tyson]

And near the center of the dense.

[Charles Liu]

Cluster, right in the center of the star, where, say, for example, in the space which is normally, say, a few light years between me and us and Alpha Centauri, for example, there could be a million stars in that space. When the over densities are a million to one compared to, say, our solar neighborhood, you can actually have stars hitting one another and they could actually explode. But the chances of even a collision causing an explosion are tiny because stars are mostly made out of gas. So imagine like a star going through another star. You're basically just having gas clouds smashing into gas clouds and go through. You need the cores.

[Paul Mercurio]

But there are molecules within each gas cloud that could sort of collide them.

[Charles Liu]

But then they don't cause a collision because they're so small.

[Paul Mercurio]

Right?

[Charles Liu]

They're so low energy. But if you can get the core of a star hit the core of a star star, then now you actually create a star happening and you create collision.

[Paul Mercurio]

Let's make that happen. Come on.

[Charles Liu]

At once every four seconds.

[Paul Mercurio]

You guys are doing crazy.

[Charles Liu]

Somewhere in the Somewhere that's higher than.

[Neil DeGrasse Tyson]

I would have guessed.

[Paul Mercurio]

I know you guys are doing crazy stuff in the basement of this place. Let's make that happen. Okay, I have more questions. I don't wanna.

[Neil DeGrasse Tyson]

I don't wanna divulge any more to you.

[Charles Liu]

I don't have the clearance.

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[Neil DeGrasse Tyson]

Paul. Time for a couple more?

[Paul Mercurio]

Oh, absolutely. Very good question. Here. This is from Morton Lurkjar. This is, I hope.

[Neil DeGrasse Tyson]

Who?

[Paul Mercurio]

Don't make me say it a second time. It's Greetings from Norway.

[Neil DeGrasse Tyson]

Sorry.

[Charles Liu]

Okay.

[Paul Mercurio]

Morton.

[Neil DeGrasse Tyson]

Oh, sorry.

[Paul Mercurio]

Morton Lurkjar.

[Charles Liu]

Lurkjar. Yes.

[Paul Mercurio]

I hope you can help clarify something for me. If our son is a third generation star, how is it that we can observe earlier generation stars when looking back in time? Since we are made up of the stardust from those earlier stars, wouldn't their light have already passed?

[Charles Liu]

Perfect answer is the following. I am a third generation from my grandfather, but I can still see my great grandfather if he's still alive. The idea is that the generation in which you are created may have happened while those earlier generations stars are still alive. So our sun is about 4 1/2 billion years old. But if a first generation star that created it was 4 billion years old, then the star that was before it was a few billion years old. But then there's a generation of stars that's 13 billion years old. We can still see them because they've still lived their lives still.

[Paul Mercurio]

But that first generation star is always going to be mom's favorite. The third generation son. Yeah, you know, you know, you leave the kid home alone, let him smoke cigarettes when he's 12, that third generation.

[Charles Liu]

You wipe the binky on the pants instead of sterilizing.

[Paul Mercurio]

You don't care by the third kid.

[Charles Liu]

Yeah, but you take the kid to.

[Paul Mercurio]

The track instead of taking him to the zoo.

[Charles Liu]

You do.

[Paul Mercurio]

I'm sorry, I'm really putting a lot of personal stuff coming out personal stuff coming out here.

[Neil DeGrasse Tyson]

Wait, Charles, I think you missed the point there.

[Paul Mercurio]

I did.

[Neil DeGrasse Tyson]

I think.

[Charles Liu]

Oh, no.

[Neil DeGrasse Tyson]

I think.

[Charles Liu]

Sorry. Sorry, Morgan.

[Paul Mercurio]

I knew that, but I didn't wanna say it.

[Neil DeGrasse Tyson]

I think. Okay. The generation of stars that gave their lives to create the elements out of which we are made are not there anymore. You're not gonna see your grandfather. If you were made out of the flesh of your grandfather or your great grandfather, they're not gonna be there. They're dead because they gave their lives for you. What's going on here is as we look out in space, we look back in time and see the universe not as it is, but as it once was. So we can look far enough out into space to see the first generation stars do their thing. And beautiful. We can look 8 billion years ago. 8 billion years ago. Those are stars manufacturing the elements. And they're about to die to make room for the second generation. And that light is only now just reaching us.

[Paul Mercurio]

But those elements continue to exist. Like my great great grandfather's DNA exists in me.

[Neil DeGrasse Tyson]

Yes, but he ain't around.

[Charles Liu]

He lives in you.

[Paul Mercurio]

Thank you. Okay, yeah.

[Neil DeGrasse Tyson]

Is that Lion King?

[Charles Liu]

Yes.

[Neil DeGrasse Tyson]

Oh yeah. Good, Very good.

[Charles Liu]

We're mixing two points.

[Neil DeGrasse Tyson]

I know there's two different points.

[Charles Liu]

There's two different points. One point is look back time and the other is the age of things.

[Paul Mercurio]

Okay, okay.

[Charles Liu]

When you have a generation of stars form, you have some stars that die quickly, but then you have a bunch of stars that live longer. So those that died quickly contributed their information or their materials to the next generation.

[Neil DeGrasse Tyson]

Their elements that they make, meanwhile, and.

[Charles Liu]

Those are the highest masses, the first generation still exists. And then that generation goes, and then they form another generation. But those old stars from the first generation still exist.

[Neil DeGrasse Tyson]

Stars that did not give their lives for us happen to live for a trillion years. Yeah, at least. So they're all still around in every galaxy and it's not even about look back time. But some of them gave their lives for us. So the notion that we are second or third generation, generally that only matters because we have elements that earlier generations have those elements.

[Paul Mercurio]

Isn't it? The third generation star, the sun's composed of heavier elements like iron and oxygen.

[Charles Liu]

Right.

[Paul Mercurio]

So that because they're heavier, they can exist longer or.

[Neil DeGrasse Tyson]

No, no, no, no, no, no, no.

[Paul Mercurio]

Pass on.

[Neil DeGrasse Tyson]

Low mass stars live forever and high mass stars die. And first generation high mass stars died for us.

[Charles Liu]

The first generation of stars, like the very, very first generation of stars, may have only formed short lived stars. This is something that has been speculated. We're not 100%.

[Neil DeGrasse Tyson]

It's like the zero generation star, the.

[Paul Mercurio]

Ones that, I'm sorry, only formed short generations lived stars. Short lived.

[Charles Liu]

Right. So it's possible that the original, the OG generation of stars is all gone. Okay, okay. But certainly we can look back several generations and see that there are stars from previous generations that still exist.

[Paul Mercurio]

Going back to your sort of analogy of the great grandmother, it's like, it's as if, if you can see those stars from previous generations that were. It's like your great grandfather's still alive. And you could go see him somewhere even though it's beautiful.

[Neil DeGrasse Tyson]

Yeah, but he's not the one who gave you your elements if you can still see him. They're not giving you the elements if they're in your own galaxy. We have all generations of stars within our own galaxy. It has nothing to do with look back time.

[Paul Mercurio]

Yeah, but the elements in that star that I can see, that's a previous generation to the sun.

[Neil DeGrasse Tyson]

They'll have fewer heavy elements than we do.

[Paul Mercurio]

Okay, but doesn't it share some of the same elements that the sun shares generationally?

[Charles Liu]

It might, yeah.

[Neil DeGrasse Tyson]

Yes. The sun has all of it, plus the next generation's worth mixed into it.

[Charles Liu]

Okay, yeah, great question, Great point.

[Neil DeGrasse Tyson]

Yeah, good one.

[Charles Liu]

Okay.

[Paul Mercurio]

Minaid Shandagai in North Wales.

[Neil DeGrasse Tyson]

Who?

[Charles Liu]

What?

[Paul Mercurio]

Yeah, who.

[Neil DeGrasse Tyson]

What's his name?

[Paul Mercurio]

Manaid Shandagai from North Wales.

[Charles Liu]

Wow. Where'd you learn your Welsh? That's amazing.

[Paul Mercurio]

Or Michael is his name. Okay. Given the relationship between speed and time, and the relationship between speed and mass, is there also, therefore, a direct relationship between time and mass? In other words, if time were somehow to stop, would everything become infinitely massive? And would we be dragged by intense gravitational forces back into singularity?

[Neil DeGrasse Tyson]

Man. Man.

[Charles Liu]

Well, I love that.

[Paul Mercurio]

That's a drop the mic moment. Everybody come out.

[Neil DeGrasse Tyson]

The mic's on a mic stand.

[Charles Liu]

Amazingly thoughtful people in Wales that are asking questions.

[Paul Mercurio]

Yes. That's incredible.

[Charles Liu]

That's incred.

[Neil DeGrasse Tyson]

So do you interpret that the way I do? He's saying, we know from relativity that as you go faster, time slows down.

[Charles Liu]

Yes.

[Neil DeGrasse Tyson]

And your mass increases. So instead of having it happen that way, let's figure out a way to slow down time. And would that then have associated with it an increase in everybody's mass?

[Charles Liu]

That's right.

[Neil DeGrasse Tyson]

That's an interesting question.

[Charles Liu]

That's a great question. I don't think that can happen. That's not how time works. Because what we're doing when we're measuring speed is how fast you are going through space. Right. It's the distance you travel through space divided by the amount of time it took you to get there.

[Paul Mercurio]

Is this question suggesting you could be dragged backwards in time somehow?

[Charles Liu]

The suggestion is that you slow time down. Right. I think that instead of going at 1 second per second, it becomes 0.9.

[Paul Mercurio]

0.8, to the point where everything becomes. Everything becomes singular.

[Charles Liu]

Right. And I don't think that can work because the physics of time, which is still mysterious at certain fundamental levels, suggests that you can't really manipulate time that way. The way you manipulate space or the way you manipulate your speed traveling through space.

[Neil DeGrasse Tyson]

That's a good point. And my favorite thought about time is that we are prisoners of the present, forever transitioning between our inaccessible past and our unknowable future.

[Paul Mercurio]

You just gave me a headache. I don't even know what you're talking about.

[Charles Liu]

You know, I know you'd like that, but I prefer maps.

[Neil DeGrasse Tyson]

You want to mess with that?

[Charles Liu]

No, but I'm going to provide an alternative from that incredible deep document. Kung Fu Panda.

[Neil DeGrasse Tyson]

Kung Fu Panda.

[Charles Liu]

From Master Oogway.

[Neil DeGrasse Tyson]

Okay.

[Charles Liu]

Right. The past is history. The future is a mystery. All we have today is a gift. And that is why it's called the present.

[Neil DeGrasse Tyson]

That was from Kung Ku Panda.

[Charles Liu]

Yes, it was.

[Neil DeGrasse Tyson]

Okay.

[Paul Mercurio]

It ain't over till it's over, Yogi. That has a time aspect, if you.

[Charles Liu]

Think about it, most profound.

[Paul Mercurio]

Don't look down your nose at that.

[Neil DeGrasse Tyson]

That only works in baseball.

[Paul Mercurio]

No, if you think about it, if.

[Neil DeGrasse Tyson]

You'Re in the super bowl and one team is down by 21 points.

[Paul Mercurio]

How about it's getting late early.

[Neil DeGrasse Tyson]

Three minutes late.

[Paul Mercurio]

Don't you love it's getting late early.

[Neil DeGrasse Tyson]

The game is over. Okay, it's not over.

[Charles Liu]

You still have to put the two minute warnings commercials in.

[Paul Mercurio]

Exactly right. You gotta sell some soap, buddy.

[Neil DeGrasse Tyson]

But the full significance of that comment can only exist in baseball where there is no clock. Except now there is with the pitcher. I think that's all the time we have. So, Charles, you finished a book recently. Yes, I loved it. The Quantum something.

[Charles Liu]

The handy Quantum physics answer book.

[Neil DeGrasse Tyson]

To have the word handy and quantum in the same title, that's badass.

[Charles Liu]

The goal is to help everyone understand which we need.

[Paul Mercurio]

Like this is basic levels, basic explanations of complex things.

[Charles Liu]

You know, quantum feels scary, it feels unknown. But actually we interact with it every day. And so think of it as a handbook. Don't think of it as a textbook.

[Neil DeGrasse Tyson]

Okay, yeah, good. Yeah.

[Paul Mercurio]

Nice reference, Guy.

[Neil DeGrasse Tyson]

And Paul, where'd. Where can we find you next?

[Paul Mercurio]

Permission to speak? My Broadway show, directed by Frank Oz.

[Pharmaceutical Representative]

Wow.

[Paul Mercurio]

The original Yoda and all of that. That and the great director. We taking on a national tour. We're going to be in Florida, in Orlando, florida. And in Fort Lauderdale at the Brow center for the Performing Arts. Dr. Phillips center in Orlando. Going to be in Rhode Island.

[Neil DeGrasse Tyson]

These all the good places.

[Paul Mercurio]

We got a set designed by the set designer for the Late show and we have animation because you, you also moonlight. I work at the Late Show. Stephen Colbert, that show you warm up, warm up and do on. I'm going to be making another appearance. I'm going to be making another stand up appearance on the show after the first year or two. And so we got a really cool.

[Neil DeGrasse Tyson]

So you don't only want with the audience. Occasionally he'll bring you on for the broadcast.

[Paul Mercurio]

I've done a bunch of appearances on the show or do sketches and things.

[Neil DeGrasse Tyson]

Like two times you came and said hi to me.

[Paul Mercurio]

I love. Yeah, every time. Yeah, absolutely. And he's like, don't make eye contact with me. I'm like, okay.

[Neil DeGrasse Tyson]

All right.

[Paul Mercurio]

And we got really cool animation in the set. It's J.J. settlemeyer who did Beavis and Butthead and all the SNL TV funhouse. We had created this. It's a multimedia show with a set with this really cool. It's really cool. So, yeah, so people go to Paul Mecurio.com, get tickets, come out, support the show would be great. Permission to speak is the name of it.

[Charles Liu]

So permission to speak.

[Paul Mercurio]

It's been really great to be on with you. I've read some of your work and it's really great. Thank you, Kim.

[Neil DeGrasse Tyson]

But you never shook my hand. He never shook my hand.

[Paul Mercurio]

Come on. I love you, bud.

[Charles Liu]

I love you. All right.

[Neil DeGrasse Tyson]

That's all the time we have. This has been a star talk. Cosmic queries. Grab bag. That was definitely some bag grabbing right there. All right, until next time, Neil DeGrasse Tyson bidding you all to keep looking up.

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[Pharmaceutical Representative]

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[Neil DeGrasse Tyson]

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[Patient]

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[Neil DeGrasse Tyson]

Machine learning at netsuite.com podcast25 netsuite.com podcast25.