Cosmic Queries – Negative Gravity

Summary

StarTalk Radio Episode Summary: "Cosmic Queries – Negative Gravity"

Release Date: May 13, 2025
Host: Neil deGrasse Tyson
Co-Host: Paul Mercurio
Episode Title: Cosmic Queries – Negative Gravity

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Introduction

In this engaging episode of StarTalk Radio, astrophysicist Neil deGrasse Tyson teams up with co-host Paul Mercurio to delve into listener-submitted cosmic queries. The duo combines science, pop culture, and humor to address complex astronomical and physical phenomena, making the universe accessible and entertaining for all listeners.

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Listener Questions

1. Will Black Holes Outnumber Stars in the Future?

   Listener: Julian from Atlanta ([15:24])

   Discussion Highlights:

   • Black Hole Formation: Paul explains that only a small fraction of stars (approximately one in a thousand) are massive enough to end their lives as black holes.

     Paul Mercurio: “The initial mass function favors low mass stars. And high mass stars are just rare.” ([18:08])

   • Black Hole Evaporation: Referencing Stephen Hawking's theory, Paul notes that black holes evaporate extremely slowly over time, ensuring they won't dominate the cosmos immediately.

     Paul Mercurio: “They will outnumber stars in a trillion years, a few trillion years when the lowest mass stars burn out their fuel.” ([18:06])

   • Long-Term Outlook: While black holes will eventually outnumber stars billions of years in the future, the current universe still boasts a vast population of stars.

2. Is the Speed of Light's Value Arbitrary?

   Listener: Cesar Fradique from Bogota, Colombia ([15:30])

   Discussion Highlights:

   • Fundamental Constant: Paul emphasizes that the speed of light (c) is a fundamental constant in physics, precisely measured and integral to defining units like the meter.

     Paul Mercurio: “You're losing gravity anytime any matter or energy leaves the system.” ([49:21])

   • Arbitrariness of Units: Neil and Paul debate whether the value of c could be different, ultimately agreeing that while units are arbitrary, the speed itself remains a constant.

     Paul Mercurio: “The units are arbitrary, but the speed that we're measuring is not. That is real and it's fundamental.” ([21:03])

3. Would a Different Star Color Affect Our Planet’s Appearance?

   Listener: Captain Carl from St. Thomas, US Virgin Islands ([30:38])

   Discussion Highlights:

   • Color Perception: Paul explains that if Earth orbited a star emitting predominantly blue or red light, the colors perceived on the planet would shift accordingly.

     Paul Mercurio: “You have Roy G. Biv. Do you know Roy G. Biv? Red, orange, yellow, green, blue, indigo, violet.” ([31:23])

   • Evolutionary Adaptations: He suggests that life forms would likely evolve to perceive the prevalent wavelengths, altering our experience of color.

     Paul Mercurio: “If we evolved there, there's no reason why our evolutionary path wouldn't have divided up the blue light into different subcategories.” ([30:49])

4. Can the Cosmic Microwave Background Serve as a Universal Clock?

   Listener: John Mayhoy from Parkland, Florida ([35:30])

   Discussion Highlights:

   • Universality of the CMB: Paul confirms that the cosmic microwave background (CMB) can act as a universal clock, as it represents a uniform snapshot of the early universe, allowing accurate age determination.

     Paul Mercurio: “Yes, because every part of the universe was in the same place at the same time 13.8 billion years ago.” ([35:35])

   • Age Consistency: The age derived from the CMB would be consistent throughout the universe, given its uniform origin.

     Paul Mercurio: “They will outnumber stars in a trillion years, a few trillion years when the lowest mass stars burn out their fuel.” ([36:46])

5. How Does Time Function in Zero Gravity and Motionless Conditions?

   Listener: Joe Liparella from Pennsylvania ([37:11])

   Discussion Highlights:

   • Relativity and Time: Paul discusses Einstein's theory of relativity, explaining that in the absence of gravity, time would pass more quickly for an object.

     Paul Mercurio: “We are losing gravity anytime any matter or energy leaves the system.” ([49:21])

   • Tachyons and Time Travel: They explore the hypothetical particles called tachyons, which travel faster than light and could theoretically move backward in time, though none have been discovered.

     Paul Mercurio: “It's called the initial mass function specifically. And the initial mass function favors low mass stars.” ([37:39])

   • Practical Implications: Neil humorously muses about anti-aging and the complexities of time manipulation.

     Neil deGrasse Tyson: “Why can’t you presume that this life form is smarter and has the ability to see what we've been doing.” ([29:25])

6. Understanding Buoyancy

   Listener: Dennis Alberti from St. Louis ([44:31])

   Discussion Highlights:

   • Basic Principles: Paul breaks down buoyancy as a function of density, explaining that objects less dense than their surrounding medium will float.

     Paul Mercurio: “It's about density and gravity. If you are less dense than the medium you're immersed in, you will float to the top.” ([44:38])

   • Applications: The conversation includes how boat design leverages buoyancy principles, transitioning from historical wooden vessels to modern metal submarines.

     Paul Mercurio: “If you carve it into a volume, the mass of the shell divided by the full volume reduces the density below water, allowing it to float.” ([45:38])

7. Gravity and Energy Loss in Nuclear Reactions

   Listener: Terry Burke from St. Louis ([47:15])

   Discussion Highlights:

   • Mass-Energy Equivalence: Paul explains that in nuclear fission and fusion, losing mass converts it into energy, which still contributes to the system's gravity due to Einstein's equation ( E = mc^2 ).

     Neil deGrasse Tyson: “So the answer is no. Is the gravity associated with the loss?” ([48:10])

   • Gravitational Impact: While mass loss would nominally reduce gravity, the equivalent energy retains gravitational influence, ensuring overall gravitational consistency.

     Paul Mercurio: “Matter and energy are one and the same thing, so they each distort the fabric of space and time.” ([48:28])

8. Supernova Remnants in the Solar System

   Listener: Mark Learned from Portland, Oregon ([50:00])

   Discussion Highlights:

   • Star Formation and Supernovae: Paul discusses how the galaxy’s rotation disperses supernova debris, which then contributes to the formation of new stars enriched with heavy elements.

     Paul Mercurio: “Supernova guts are scattered everywhere, and the galaxy's differential rotation shears the gas clouds, mixing the debris.” ([50:16])

   • Galactic Recycling: This process ensures that elements from past supernovae are incorporated into future generations of stars, fostering a cycle of stellar evolution and material enrichment.

     Paul Mercurio: “Next generation of stars is gonna have all the ingredients from that last round of supernova explosions.” ([50:54])

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Conclusion

Throughout "Cosmic Queries – Negative Gravity," Neil deGrasse Tyson and Paul Mercurio adeptly bridge the gap between intricate scientific concepts and everyday understanding. Their insightful discussions not only answer listener questions but also spark curiosity about the universe's vast and mysterious nature. By intertwining humor with expertise, the episode exemplifies StarTalk Radio's mission to make science entertaining and accessible to all.

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Notable Quotes with Timestamps

• Black Holes and Stars:

  Paul Mercurio: “The initial mass function favors low mass stars. And high mass stars are just rare.” ([18:08])

• Speed of Light:

  Paul Mercurio: “The units are arbitrary, but the speed that we're measuring is not. That is real and it's fundamental.” ([21:03])

• Relativity and Time:

  Paul Mercurio: “We have stars today that are born out of these pockets of gas that are still alive and thriving, and we've only had one or two black holes, so. No. Black holes do not outnumber stars.” ([18:06])

• Buoyancy:

  Paul Mercurio: “It's easy and simple. If you have less density than the medium, you float.” ([44:38])

• Mass-Energy Equivalence:

  Paul Mercurio: “Matter and energy are one and the same thing, so they each distort the fabric of space and time.” ([48:28])

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Final Thoughts

This episode of StarTalk Radio showcases the dynamic interplay between Neil deGrasse Tyson and Paul Mercurio, offering listeners a captivating exploration of cosmic phenomena. Whether contemplating the future balance of stars and black holes or unraveling the nuances of buoyancy, the hosts provide clarity and intrigue, encouraging all to keep looking up.

Transcript

[Rob Lowe]

Hey, everybody, it's Rob Lowe here, if you haven't heard. I have a podcast that's called Literally with Rob Lowe. And basically, it's conversations I've had that really make you feel like you're pulling up a chair at an intimate dinner between myself and people that I admire, like Aaron Sorkin or Tiffany Haddish, Demi Moore, Chris Pratt, Michael J. Fox. There are new episodes out every Thursday, so subscribe, please, and listen wherever you get your podcasts.

[Neil DeGrasse Tyson]

You know that feeling when someone shows.

[Paul Mercurio]

Up for you just when you need it most?

[Neil DeGrasse Tyson]

Yeah.

[Paul Mercurio]

I mean, we all need that. That's what Uber's all about. Not just a ride or dinner at your door.

[Neil DeGrasse Tyson]

It's how Uber helps you show up for the moments that matter. Because showing up can turn a tough day around or make a good one even better. Whatever it is, big or small, Uber.

[Paul Mercurio]

Is on the way, so you can be on yours. Uber, on our way, Paul. People loving them, some relativity.

[Neil DeGrasse Tyson]

Oh, man. We got general.

[Paul Mercurio]

We got special man with time dilation and space and curvature. It never stops.

[Neil DeGrasse Tyson]

You know what? I was feeling a little time dilation, like a little spilkess. But I'm feeling all right now.

[Paul Mercurio]

All that and more coming up on StarTalk. Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk. Neil DeGrasse Tyson here, your personal astrophysicist. We're gonna do cosmic queries today. I have Paul Mercurio.

[Neil DeGrasse Tyson]

Paul, what's up, my friend?

[Paul Mercurio]

Welcome back to Start Talk.

[Neil DeGrasse Tyson]

Great to see you.

[Paul Mercurio]

What'd you do with Chuck? What'd you do? What'd you do?

[Neil DeGrasse Tyson]

You know, he's in a bag somewhere. Last time checked, he was breathing.

[Paul Mercurio]

He was still breathing. So how you been, man?

[Neil DeGrasse Tyson]

I'm good.

[Paul Mercurio]

I miss you. I miss you. Still doing the Late Show.

[Neil DeGrasse Tyson]

Doing the Late show with Stephen Colbert. Just did another appearance on that. I've been touring with my Broadway show. Permission to speak. Directed by Frank Oz.

[Paul Mercurio]

Frank Oz. He's the voice of Yoda.

[Neil DeGrasse Tyson]

He's Yoda. He's a mensch, as they say. He's a great. He's just a brilliant artist.

[Paul Mercurio]

We love him. We love him.

[Neil DeGrasse Tyson]

Yeah, he is.

[Paul Mercurio]

He's been on our show. You'll find him in our archives.

[Neil DeGrasse Tyson]

Oh, he's amazing. And he's just.

[Paul Mercurio]

And you'll see all how the breadth and depth of all that he is.

[Neil DeGrasse Tyson]

Oh, the Muppet creator with Jim Henson of the Muppy creator, Miss Piggy, and Fozzie. Bear directed everybody from Marlon Brando to Robert De Niro to me. I don't know what that's about. He's really a step down. I think he's living in his car by the river.

[Paul Mercurio]

We love. So this is a grab bag.

[Neil DeGrasse Tyson]

This is a grab bag. We love these.

[Paul Mercurio]

I haven't seen them before.

[Neil DeGrasse Tyson]

No.

[Paul Mercurio]

If I don't know the answer, I'll just say I don't know.

[Neil DeGrasse Tyson]

Yeah. Oh, you know. You always know the answers. Okay, here we go. Eric Krasjidoti Dr. Tyson in Duke Mercurio. Wow. Never been called a Duke before.

[Paul Mercurio]

Oh. Cause Chuck is called Lord. Oh, Lord. Nice.

[Neil DeGrasse Tyson]

Oh, I didn't. Oh, okay, okay.

[Paul Mercurio]

Everybody's got a title.

[Neil DeGrasse Tyson]

I'm a duke now. There we go. I hope that Matt is at home with my wife.

[Paul Mercurio]

But are you Duke of Earl? What? Are you Duke of Earl? All right, they got Lord Duke, Duke.

[Neil DeGrasse Tyson]

Yo, you can do that? I can do Duke.

[Paul Mercurio]

Duke, Duke, Duke, Duke of Earl.

[Neil DeGrasse Tyson]

We're just gonna do this for 30 minutes.

[Paul Mercurio]

Duke of Earl. Then you gotta come in high, give me some falsetto. We'll find out what you're Duke of. We'll come up with something.

[Neil DeGrasse Tyson]

Greetings from Mongahela, Pennsylvania, regarding the idea of time travel in star position. Hypothetically, if I were to create a time machine attempt to go back to Mongohela 2000 years ago, would I not end up in empty space? Because the entire solar system would not have arrived in that location had I departed. That I had departed from.

[Paul Mercurio]

Every time machine is also a space machine. They're space time machine. They don't say it, but they have to be.

[Neil DeGrasse Tyson]

Why is that relevant? And why does that matter?

[Paul Mercurio]

They have to be. Now, they got around that in Back to the Future because when Marty is trying to escape from the Libyan terrorists and he jumps in the DeLorean and he's quickly typing the date, he types 1955, but it's the same day of the year as he leaves. So he goes back to 1955. Earth is in the same part of its orbit on that day around the.

[Neil DeGrasse Tyson]

Sun because of the date. The date.

[Paul Mercurio]

The date was the same. So. So they skirted.

[Neil DeGrasse Tyson]

But that can't be true because of the years.

[Paul Mercurio]

Hang on, hang on. So they dodged that bullet a little bit, okay? Had it been six months earlier or later, he'd just be plopped in the vacuum of space and he'd be dead, okay? So the reason why they dodged that bullet is because the entire solar system is also orbiting the center of the galaxy.

[Neil DeGrasse Tyson]

It happened to pick the exact date. That was the key there.

[Paul Mercurio]

Well, only for the moving coordinate system, that is the solar system. Okay, but because the whole solar system is moving. He goes back 30 years. He's leaving our solar system today. And if he only moved in time, he would be where our solar System is today 30 years ago.

[Neil DeGrasse Tyson]

But he also moved in.

[Paul Mercurio]

He would've been well ahead of where the solar system would have gotten. The solar system would need another 30 years to catch up.

[Neil DeGrasse Tyson]

But he also moved in space, is your point. Not just in time, which is why.

[Paul Mercurio]

He landed in exactly the same spot on Earth. So it's implicit in the storytelling. So you're absolutely right. Nothing. You can't do that in any way that makes sense.

[Neil DeGrasse Tyson]

But wait, if our solar system formed about 4.6 billion years ago, Isn't the premise part of his question has a false premise, which is I would not end up in. Because the entire solar system would not have arrived in the location. Solar system is there in that location.

[Paul Mercurio]

No, no, no, no. We're in a rotating galaxy. The Milky Way is rotating, and so that is all the stars in the Milky Way are rotating around our central black hole in the center. So if you go back in time, if you go back in time, you are no longer where you left in space and you'll be dropped in the middle of nowhere. So you always have to land in a space time coordinate in the future. We sort of do that, but without the relativity part. If you're going to visit Mars, you don't aim for where Mars is. You aim for where Mars will be when you get there. Then you intersect Mars.

[Neil DeGrasse Tyson]

So if you're going back 2,000 years, it will be an empty. Well, there's going to be a Home Depot because they existed in a Subway sandwich shop. They've been around in the mall. Yeah, well, I mean, you know, their franchising methodologies is brilliant and they never get enough credit.

[Paul Mercurio]

What you need is you have to know where was the solar system and the Earth 2000 years ago and not only move back in time, but move back to that location.

[Neil DeGrasse Tyson]

But you cannot say that the Mangahela would not be the Mangahela 2000 years ago. Why wouldn't it be? Why would not it be exactly what it is today?

[Paul Mercurio]

The Mangahela sounds like a native tribe.

[Neil DeGrasse Tyson]

It is.

[Paul Mercurio]

That's who would be there 2,000 years ago.

[Neil DeGrasse Tyson]

He's asking if I create a time machine and then we go back to Mangahela, would I not end up in an empty space?

[Paul Mercurio]

Yes, he Would. Unless he moved in time. That's what I've been spending the last 10 minutes describing.

[Neil DeGrasse Tyson]

I understand that. So your answer. Your answer to his question is yes.

[Paul Mercurio]

Yes. Unless he also moves back into space as well. Correct.

[Neil DeGrasse Tyson]

Got it. Okay.

[Paul Mercurio]

And yes. So every time machine is also a space machine. Otherwise it would be quite lethal most of the time.

[Neil DeGrasse Tyson]

What would happen?

[Paul Mercurio]

No, you get dropped in the middle of space because everything's moving. You gotta move with the action.

[Neil DeGrasse Tyson]

Okay. Margo Lane.

[Paul Mercurio]

Mm.

[Neil DeGrasse Tyson]

If you are a life form on a pristine planet, watching exploratory humans arrive for the first time. Okay, so you're observing humans arrive for the first time.

[Paul Mercurio]

Yes.

[Neil DeGrasse Tyson]

What is the first question you'd ask them, assuming you could understand each other? And I have the answer to this. My question would be, really? You needed sketcher shoes where you don't have to bend over to put them on.

[Paul Mercurio]

That's where you were in TV commercials.

[Neil DeGrasse Tyson]

Forget about that. That's where we are as a species. There's a lot of questions. The Kardashians.

[Paul Mercurio]

What?

[Neil DeGrasse Tyson]

Why? Really?

[Paul Mercurio]

What's up with that?

[Neil DeGrasse Tyson]

How do people who make Vaseline make any money? Think about it. I've had the same tub of Vaseline. My Vaseline was handed down to me by my grandfather in a will. I don't think you understand these conceptual. Okay, here we go.

[Paul Mercurio]

I think people used to use Vaseline before. Lotion was big.

[Neil DeGrasse Tyson]

I used it to grease the brakes on my car. And I still have a giant bat of it.

[Paul Mercurio]

Tubs of Vaseline are not as, you.

[Neil DeGrasse Tyson]

Know, you could go through 30,000 bags of garbage, you're not going to find one empty container of acid. All right, so if you're a life form on a pristine planet, watching exploratory humans arrive, what is the first question you would ask exploratory humans?

[Paul Mercurio]

Okay, so first let me say that you should look online. Maybe Pluto tv or one of these things that has old TV in it.

[Neil DeGrasse Tyson]

Me tv?

[Paul Mercurio]

Me tv. Yeah, but. And there's several others as well. Go to an old episode of the Twilight Zone called the Invaders. That's all I will say.

[Neil DeGrasse Tyson]

Well, I watch a lot of Twilights. I'm trying to remember which one that is.

[Paul Mercurio]

So in that episode, Agnes Moorhead is this lone ranch woman on a Little House on the Prairie. And the whole. It's a one woman show. She's the only character in it. And you just have to watch that. It's called the Invaders.

[Neil DeGrasse Tyson]

Oh, I do remember this now.

[Paul Mercurio]

It's called the Invaders. Okay, don't say anything about it point is, if I'm the other life form and I see humans, my first question would be, just given what I know about humans, have you come to colonize this planet? Cause if that's your goal, that's not happening. Okay. We will not let that happen. Okay. Because we've seen what happens when you colonize stuff before.

[Neil DeGrasse Tyson]

Yeah.

[Paul Mercurio]

Okay.

[Neil DeGrasse Tyson]

Yeah.

[Paul Mercurio]

So that's the first point. Second, that's interesting because that implies that the humans have more technology than the alien in that case. Yeah. Because otherwise the aliens would have visited us first.

[Neil DeGrasse Tyson]

No, that's. You just come to the conclusion. No, you're missing it. The question you gotta ask is really, you conveyed happiness by a little yellow circle with a smiley face called an emoji. There are so many bigger questions that you could ask these people.

[Paul Mercurio]

Yeah, that's true.

[Neil DeGrasse Tyson]

No, the colonization is a good point because nothing good ever has really happened from that. It's good and it's.

[Paul Mercurio]

But how about this? I would say, how did you survive yourselves enough to then come visit another planet? That's what I mean.

[Neil DeGrasse Tyson]

Maybe what you would do is you would be hiding behind something and you'd say, how do you feel about brothers? You know, you gotta ask the black question. Cause you know. Cause if they're not with the thing. No, maybe you just say, what part of the are you from?

[Paul Mercurio]

Oh, I see. What part of the demographic?

[Neil DeGrasse Tyson]

Well, if you see them goose stepping down toward you, you probably know, if you're a Jew or a black person, you may want to let them just pass.

[Paul Mercurio]

Or gypsies or Catholics.

[Neil DeGrasse Tyson]

Or gypsies or Catholics or pretty much anybody.

[Paul Mercurio]

Yeah, yeah. Anyone non Aryan.

[Neil DeGrasse Tyson]

Wouldn't you ask them how you got there though? Seriously, what was your technology that got you to watch?

[Paul Mercurio]

I would assume they would see them land in something.

[Neil DeGrasse Tyson]

No, no, but. But you'd want to learn from that.

[Paul Mercurio]

No, as a scientist, I would compare notes.

[Neil DeGrasse Tyson]

Yeah.

[Paul Mercurio]

And I would do things. There's certain things that should be common between us even if we don't otherwise speak the science.

[Neil DeGrasse Tyson]

What is this thing you call Tang? Like that kind of thing.

[Paul Mercurio]

But how would I know that though? That's what I'm saying. I don't know the Tang or the Kardashians or slip on skitchers. I don't. Unless he shows up drinking Tang.

[Neil DeGrasse Tyson]

Do you have to ruin every joke and party with your stupid logic with.

[Paul Mercurio]

A Kardashian underarm and slip on schedule? Then I could ask what's up with that?

[Neil DeGrasse Tyson]

Why can't you presume that this life form is Smarter and has the ability to see what we've been doing.

[Paul Mercurio]

Here's what I would say. I want to know. I want to compare science notes. Because science transcends time and space in ways culture does not.

[Neil DeGrasse Tyson]

But it doesn't transcend Instagram. If you got a big following, that's all that matters.

[Paul Mercurio]

So if I verify that they can see in the same wavelengths of light that I can see, they could have completely different senses.

[Neil DeGrasse Tyson]

Well, I was gonna say medically, you'd probably wanna check each other out too, right?

[Paul Mercurio]

Not first.

[Neil DeGrasse Tyson]

No, no, I don't mean to start.

[Paul Mercurio]

Poking their bodies first.

[Neil DeGrasse Tyson]

No, I didn't mean it in that way. No, I'm not talking about like anal probes or anything. I'm just saying. You thought of that.

[Paul Mercurio]

Don't give the alien a bad name now.

[Neil DeGrasse Tyson]

No, I'm saying no. Why wouldn't. If you wanna check out their mind and compare notes in terms of science, wouldn't you? Physic? I would physically want to understand their bodies versus vis a vis my vessel, their vest vessel. No.

[Paul Mercurio]

So if I were a biologist, yes, but I'm a physicist, so no, I'd compare. I'd pull out a periodic table of the elements, because that organization is universal. Anyone who knows the elements well enough as well as we do would organize them that way.

[Neil DeGrasse Tyson]

Okay, but what if somebody that landed was like a right, a creature creative writing major and didn't care about science?

[Paul Mercurio]

If they were the first emissary to another planet, I'm pretty sure they would have given them some science.

[Neil DeGrasse Tyson]

Yeah, you're just a science snob. Oh, only we're the ones that everybody cares about.

[Rob Lowe]

Hey everybody, it's Rob Lowe here. If you haven't heard, I have a podcast that's called Literally with Rob Lowe. And basically it's conversations I've had that really make you feel like you're pulling up a chair at an intimate dinner between myself and people that I admire, like Aaron Sorkin or Tiffany Haddish, Demi Moore, Chris Pratt, Michael J. Fox. There are new episodes out every Thursday, so subscribe please and listen wherever you get your podcasts.

[Paul Mercurio]

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[Neil DeGrasse Tyson]

Shoes are an important part of, well.

[Paul Mercurio]

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[Neil DeGrasse Tyson]

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[Paul Mercurio]

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[Neil DeGrasse Tyson]

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[Paul Mercurio]

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[Neil DeGrasse Tyson]

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[Paul Mercurio]

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[Neil DeGrasse Tyson]

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[Paul Mercurio]

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[Neil DeGrasse Tyson]

I'm Jasmine Wilson and I support StarTalk on Patreon.

[Paul Mercurio]

This is StarTalk with Neil DeGrasse Tyson.

[Neil DeGrasse Tyson]

Hello, Neal and Paul. This is Julian, Atlanta native, writing from downtown Manhattan. My question relates to stars and black holes. I understand that our sun belongs to the third generation of stars since the Big Bang. Each star will eventually die out in an explosion, some of which form black holes ending in eternal singularity of their mass. Is it possible that in the distant future there will be more black holes than stars since their lifespan is so much longer than that of a star? Could the passage of time create a population of black holes that outlive and nearly replace stars?

[Paul Mercurio]

Yes. Next question. Okay, so it turns out, according to Stephen Hawking, black holes actually evaporate, but very, very, very slowly.

[Neil DeGrasse Tyson]

So it's not burnout, it's evaporate. It's a different.

[Paul Mercurio]

Yeah, they wouldn't burn out very, very, very slowly. So there's a point where all the stars burn out and they leave their corpses. Some of those corpses are black holes. And there will come a time when the black holes outnumber the living stars. They will never outnumber the quartz.

[Neil DeGrasse Tyson]

But isn't the black hole then like. It's like the Alice in the Brady Bunch with a giant vacuum cleaner. It's like sucking up all of the stars, whether they evaporate or not.

[Paul Mercurio]

I don't. Alice in the Brady Bunch.

[Neil DeGrasse Tyson]

Yeah, the housekeeper.

[Paul Mercurio]

Is that what she did?

[Neil DeGrasse Tyson]

She was. She would vacuum the black holes? Yes.

[Paul Mercurio]

I'm sorry, I can't connect. I'm sorry. Do you see? Where was Alice in the grid of nine squares?

[Neil DeGrasse Tyson]

She was in the center.

[Paul Mercurio]

She was in the center. And if you notice, her image kept repeating back and forth because it had the technology. It was a pretty short loop.

[Neil DeGrasse Tyson]

Right.

[Paul Mercurio]

And I got annoyed by it.

[Neil DeGrasse Tyson]

It's the same thing in the Mad, Mad, Mad, Mad World. Yeah, I just saw it last night.

[Paul Mercurio]

Really?

[Neil DeGrasse Tyson]

No, I'm serious, okay?

[Paul Mercurio]

I know every frame of that movie.

[Neil DeGrasse Tyson]

Okay, so there's the shot when, at the end, Spencer Tracy is hanging Onto the edge. He slides down a cable and goes through a window and is sitting there and a Great Dane is licking his face.

[Paul Mercurio]

Yes. And that's a repeated.

[Neil DeGrasse Tyson]

And it's a repeated. And it was annoying me as well. I don't know how he got off on that, but it's like. And he's doing this with his eyes moved the same way. But is it possible there are already more black holes than stars in our universe?

[Paul Mercurio]

No, because we know who the progenitor is of a black hole. And it's a star that's made one out of 10,000 stars, or one in a million star. It's the most massive of stars is a black hole. And in any volume of gas that creates stars, it creates a lot of low mass stars and fewer middle mass stars and very few high mass stars.

[Neil DeGrasse Tyson]

So is this like a cosmic game of hide and seek?

[Paul Mercurio]

It's called the initial mass function specifically. And the initial mass function favors low mass stars. And high mass stars are just rare. Rare. And I don't know the latest iteration on the initial mass function, but it's at least as rare as one in a thousand stars that what are massive enough to make a black hole at the end of its life. So all I'm saying is we have stars today that are born out of these pockets of gas that are still alive and thriving, and we've only had one or two black holes, so. No. Black holes do not outnumber stars, by the way. They will outnumber stars in a trillion years, a few trillion years when the lowest mass stars burn out their fuel.

[Neil DeGrasse Tyson]

It just sounds like stars need like a support group for black holes in the way they get dealt with.

[Paul Mercurio]

No, they'll be fine. Black holes need no support.

[Neil DeGrasse Tyson]

The more black holes that develop, we're all in jeopardy.

[Paul Mercurio]

No, I just avoid them, that's all.

[Neil DeGrasse Tyson]

Well, but what you do emotionally in your relationships to other people is not what's relevant here.

[Paul Mercurio]

Yeah, we just need a map of where all the black holes are and then step around them. Especially in your time machine. You don't want your time machine to land in a black hole because you didn't type in the right space time coordinate.

[Neil DeGrasse Tyson]

All right, let's move on. I think we answered that thoroughly. Cesar Fradique from Bogota, Colombia.

[Paul Mercurio]

Love it.

[Neil DeGrasse Tyson]

Speed of light C shapes our reality and its fundamental properties. However, it is intriguing to consider that regardless of the unit used, C could potentially be half, double, or any other value. Could you suggest factors other than the possibility of it being an imposed constraint within a Simulation that might determine the seemingly arbitrary value of this universal constant as we understand it.

[Paul Mercurio]

Wow. Here's a couple of speed of light facts.

[Neil DeGrasse Tyson]

299,792,440 meters per second.

[Paul Mercurio]

Yes, yes.

[Neil DeGrasse Tyson]

And do you know where the C comes from? The Latin word speed, C stands for constant. Yeah, but they think that. But there's a speculation from a 1922 historian and scientist that it's seletrius, the Latin for speed.

[Paul Mercurio]

That's the first I've heard of that.

[Neil DeGrasse Tyson]

Well, that's why I'm here. To open your horizons.

[Paul Mercurio]

That's the first I've heard of that.

[Neil DeGrasse Tyson]

It's true.

[Paul Mercurio]

First I've heard of that.

[Neil DeGrasse Tyson]

That doesn't mean. It's not.

[Paul Mercurio]

It's the most fundamental constant in the universe.

[Neil DeGrasse Tyson]

Right.

[Paul Mercurio]

And the word constant begins with a C. I understand.

[Neil DeGrasse Tyson]

But there's an artist.

[Paul Mercurio]

So if I'm wrong, I'd be intrigued to learn that that's what was really going on.

[Neil DeGrasse Tyson]

Okay.

[Paul Mercurio]

It's not just an after the fact that suggestion. Okay, so the units are arbitrary. Completely arbitrary. You said you're. How tall are you? 59 mm? If I measured your height in units of 59 ness, then how tall are you?

[Neil DeGrasse Tyson]

Those unit. Those number of units. 5 9.

[Paul Mercurio]

If I have a new unit that's 5ft 9 inches and I'm one unit, you're one.

[Neil DeGrasse Tyson]

Okay, so your point being?

[Paul Mercurio]

That doesn't make you shorter or taller.

[Neil DeGrasse Tyson]

Or anything but your point?

[Paul Mercurio]

I'm saying that the units are arbitrary, but the speed that we're measuring is not. That is real and it's fundamental.

[Neil DeGrasse Tyson]

So the units don't matter.

[Paul Mercurio]

And so precisely do we understand the speed of light. It's been measured so precisely that it defines the length of the meter. That's how well we know the speed of light. So if we get another point of precision in the measurement of the speed of light, it affects the definition of the length of the meter.

[Neil DeGrasse Tyson]

So you can vary that.

[Paul Mercurio]

Well, only in the points where it's still uncertain. That's correct. But it's the most amazing fundamental thing there is.

[Neil DeGrasse Tyson]

So there is no inherent. There cannot be any inherent uncertainty around the speed of light is what you're saying.

[Paul Mercurio]

Whatever uncertainty there is, it's smaller than our capacity to measure it.

[Neil DeGrasse Tyson]

Then how do you know that there is uncertainty if you can't measure it?

[Paul Mercurio]

There is always uncertainty in every measurement.

[Neil DeGrasse Tyson]

How do we know that?

[Paul Mercurio]

Always?

[Neil DeGrasse Tyson]

How do we know that?

[Paul Mercurio]

So how tall are you again?

[Neil DeGrasse Tyson]

Five nine.

[Paul Mercurio]

Are you five nine and a quarter? Are you five eight and three quarters. Are you five, eight and seven, eight. Are you five, nine and one eighths. Are you five, nine and 1, 16. How come you gave it to me in units of inches? You've approximated, haven't you?

[Neil DeGrasse Tyson]

Well, it depends on what socks I'm wearing.

[Paul Mercurio]

You have approximated it. So now I measure you at 5, 9. Let's say you're exactly 5, 9, 5ft, 9 inches. What does that even mean? The thickness of the line. That's the nine inches above the five feet. Where are you within the thickness of that line? Are you 5, 8 and 99, one hundredths of an inch? Are you 5, 9 and 1 1,000th of an inch.

[Neil DeGrasse Tyson]

So you're saying exactitude is impossible?

[Paul Mercurio]

Correct. Always.

[Neil DeGrasse Tyson]

Everywhere.

[Paul Mercurio]

You can never measure something exactly.

[Neil DeGrasse Tyson]

Is that because of the space time continuum?

[Paul Mercurio]

No, they're what's called measurement errors. But they're not errors. They're just measurement uncertainties. So if you were once 5, 8, and then you're later on 5, 10, there was a point in your life where you were exactly five, nine, but you could have never measured it to be. So all you could do is measure it and bracket it according to the uncertainties of your measuring device.

[Neil DeGrasse Tyson]

Right now I'm exactly five, nine. I felt it.

[Paul Mercurio]

Little vibration.

[Neil DeGrasse Tyson]

Little vibration.

[Paul Mercurio]

So measurements are never exact and they.

[Neil DeGrasse Tyson]

Never can be and they never will be.

[Paul Mercurio]

That's correct. You can only know them with greater precision.

[Neil DeGrasse Tyson]

And you're how tall?

[Paul Mercurio]

At my tallest, six, two.

[Neil DeGrasse Tyson]

But you're shrinking.

[Paul Mercurio]

Yeah, I'm probably shrinking.

[Neil DeGrasse Tyson]

Is that your spine collapsing?

[Paul Mercurio]

The discs between your spinal column fluid? Yeah. But you can go into space and grow an inch or so, but your space suit that you walk in in the spacewalk is made taller than the one you took off in.

[Neil DeGrasse Tyson]

Why are we growing? Because gravity.

[Paul Mercurio]

Gravity's no longer squashing you.

[Neil DeGrasse Tyson]

So the atoms are getting stretched out.

[Paul Mercurio]

Yeah. The molecules, it stretches out. Right. So I'm probably six, one and three quarters now.

[Neil DeGrasse Tyson]

I guess you are, as they say in science, a tall drink of water. All right, here we go.

[Paul Mercurio]

Doesn't that mean you have great affection for me?

[Neil DeGrasse Tyson]

Knows no bounds. It's boundless. All right. Stephan Summers, this is Steph from Heston, Kansas. I was making my way through your small towns.

[Paul Mercurio]

I love it.

[Neil DeGrasse Tyson]

Yeah. Making my way through your old queries and found one where you talked about how if we could pass through wormholes, then gravity would as well. But my understanding is that gravity is the warping of space. And since a wormhole is making a hole through the dimension of Space, would it be warped on the other side? Furthermore, if a wormhole is a literal hole through a dimension, would we be able to pass through it or even perceive it as being. As beings who live within our three dimensional space?

[Paul Mercurio]

Wow, that sounds like he wants to write another. The sequel to.

[Neil DeGrasse Tyson]

I was going to say. Do you want me to repeat anything?

[Paul Mercurio]

No, no, no, no, no. He wants to write the sequel to Interstellar. That's what he's trying to do there.

[Neil DeGrasse Tyson]

Exactly.

[Paul Mercurio]

So a wormhole uses, if we were to make one, uses negative gravity. So we know how to make a wormhole. We just don't have the stuff, the substance, to make it happen. Gravity collapses space time on itself. Negative gravity. If we could, negative matter would pry.

[Neil DeGrasse Tyson]

Open space time and creates a shortcut through.

[Paul Mercurio]

So if we did that, we in principle should be able to position it in such a way that pops a hole through the fabric of space and time and you step through and you're instantly on the other side. Which by the way, would have rendered transporters completely obsolete in Star Trek. Think about it. Just step through a wormhole to get down to the planet.

[Neil DeGrasse Tyson]

Yeah, but there's no guarantee you're going to get through without getting lost. It's like Google Maps and you take a right and then suddenly you're in a cornfield.

[Paul Mercurio]

I'll take that chance.

[Neil DeGrasse Tyson]

Because you don't pay attention to Google Maps.

[Paul Mercurio]

I'll take that chance over dematerializing my body into energy and rematerializing it back into matter on the other side.

[Neil DeGrasse Tyson]

Why do you think that that's not possible? Because you like your nose ends up on your cheek.

[Paul Mercurio]

I know anything. Anything. My thoughts, my memories stored in the synapses of my brain. I don't know what's gonna do to that.

[Neil DeGrasse Tyson]

Maybe it could help. Let's say you misplace your keys all the time. Suddenly things should be arranged. And you know where your Shakti's are at all the time?

[Paul Mercurio]

That's a possibility. But the brain is so complex, I'm guessing that if you dematerialize it and rematerialize it, chances are you'll mess it up rather than improve it.

[Neil DeGrasse Tyson]

Okay, but if we're 3D and a wormhole is in another dimension, how do we even know it's there? It's like trying to change a flat not knowing where the car is.

[Paul Mercurio]

We see the part of the wormhole that intersects our dimensionality, but it's only.

[Neil DeGrasse Tyson]

Part of the wormhole.

[Paul Mercurio]

Well, so here's an example I gave in another show. If we live in a flat sheet of paper, and then we're just standing around and we see a dot just appear out of nowhere. That dot becomes a small circle and then a big circle. We're just watching this and then it shrinks back again, becomes a dot, and then disappears. That'd be freaky.

[Neil DeGrasse Tyson]

No, that's called a Vegas act. It's a magician. He works at the lounge.

[Paul Mercurio]

Completely freaky. Bellagio, what you just witnessed was a three dimensional sphere passing through the two dimensions of your world. And you described it as a point, and then circles that grew until the circle was as wide as the diameter of this sphere, and then it went back and then disappeared as it passed through to the other side. So higher dimensional things passing through our dimensionality will manifest in some way or another.

[Neil DeGrasse Tyson]

So in answering this question, then the answer is, if a wormhole is a literal hole through a dimension, will we be able to pass through it or even perceive it as being. As beings who live within our three dimensions? Yeah, you can perceive.

[Paul Mercurio]

You would see the part of the wormhole that intersected our dimensionality, but nothing more than that. You won't appreciate all of what else is going on there. The fact that it moves into a fourth dimension, you're not going to catch that.

[Neil DeGrasse Tyson]

But if you're passing through a wormhole, you're gonna instantly get to the other side.

[Paul Mercurio]

Instantly. Instantly. So what movies like showing that you're going through this tunnel? You know, it's like in the water park. No, it's correctly done in Rick and Morty.

[Neil DeGrasse Tyson]

Which is exactly why I watch Rick and Morty for my science knowledge.

[Paul Mercurio]

And this dude, what's his name? Dr. Strange. You know what I'm talking about?

[Neil DeGrasse Tyson]

I would. If I had a superpower, I just would want to be able to do that. It's a very sophisticated, understated. It's not this. It's not trying too hard. It's like.

[Paul Mercurio]

Yeah, I mean, I prefer the Rick and Morty wormholes because Rick uses real science.

[Neil DeGrasse Tyson]

And what is it about that wormhole in Rick and Morty that's accurate to you?

[Paul Mercurio]

No, he just uses real science, whereas doctor Strange uses magic.

[Neil DeGrasse Tyson]

If you can't perceive a wormhole, aren't we, in a way, like, walking through life like the tourists that are lost in New York City, just looking up, taking pictures at everything?

[Paul Mercurio]

Yes.

[Neil DeGrasse Tyson]

And isn't there a way that science can sort of make us not feel that way?

[Paul Mercurio]

Deal with it. You can't become a scientist unless you are comfortable being steeped in ignorance.

[Neil DeGrasse Tyson]

Okay, so we have this constant debate. This is where you just, like, try to get off on being lazy and not trying to get stuff right.

[Paul Mercurio]

No, I want to get stuff right.

[Neil DeGrasse Tyson]

Oh, whoa. It's better to not know anything. All right, let's go have a bottle of wine.

[Paul Mercurio]

No, it's learn to love the questions themselves.

[Neil DeGrasse Tyson]

Oh, my God. I went through law school. I don't need this adjutant. Answer a frigging question, will you? You know, talking to you about science, like looking at a Picasso, and then you're like, whoa, why is the nose on his calf? I don't know. And then some historian, art historian, has a theory, and they're completely full of, you know what? Okay, you know what? You're fired from science.

[Paul Mercurio]

I don't think he ever put his nose on his calf.

[Neil DeGrasse Tyson]

Yes, he did. All right, here we go. Oh. This is Captain Carl with two K's, everybody. Ahoy, Captain Carl from St. Thomas, US Virgin Islands. I've often wondered, as a photographer and as physics enthusiast, is our colorful world a result of our white star, White being made up of all colors? What if our planet or any planet was orbiting a blue or red star? Would our world be different shades of red or blue? By the way, I just want to thank you, Neil, and shout out to your comedic sidekicks. So, would our worlds be different shades of red or blue if we were orbiting a blue or red star with our current eyes?

[Paul Mercurio]

Yes. But if we evolved there, there's no reason why our evolutionary path wouldn't have divided up the blue light into different subcategories.

[Neil DeGrasse Tyson]

Yeah, but if you have pure red, then entire Earth's gonna feel like a brothel.

[Paul Mercurio]

Yeah.

[Neil DeGrasse Tyson]

However, don't pretend you don't know what that is.

[Paul Mercurio]

The width of our sensitivity to light is much greater than any single band of light.

[Neil DeGrasse Tyson]

Say that again. You lost me.

[Paul Mercurio]

All right, so you have Roy G. Biv. Do you know Roy G. Biv? You don't know Roy? Red, orange, yellow, green, blue, indigo, violet. Roy G. Biv.

[Neil DeGrasse Tyson]

Okay.

[Paul Mercurio]

You never knew that?

[Neil DeGrasse Tyson]

No, I never. No.

[Paul Mercurio]

Gotta learn something every day.

[Neil DeGrasse Tyson]

Yeah. That's why I'm here.

[Paul Mercurio]

Okay. Okay, Roy G. Biva. We see all those colors now when we make color photos by Hubble or the James Webb Telescope in the infrared part of the spectrum. You can't see colors in the infrared part of the spectrum. So you know what we do? We take rgb, slap it onto different wavelengths in the infrared part of the spectrum and create a color photograph out of it. That's what you would see if our sight was shifted to the Infrared part of the spectrum. It's what the world would look like.

[Neil DeGrasse Tyson]

So the infrared part of the spectrum, is it neutral in color?

[Paul Mercurio]

You can't detect it at all. But if we evolved to see it, there's no reason to think our brain wouldn't assign colors to it. That's what's going on here. We're assigning colors. In fact, Richard Dawkins, the evolutionary biologist, thinks that bats actually, when they echolocate, they see in color because their mammal brain has that capacity. So why not use it? So when you're using echolocation, tag it with a color.

[Neil DeGrasse Tyson]

So if we orbited. If we orbited a blue star, would we still have clear skies? In other words, every star?

[Paul Mercurio]

If our eyes evolved in this star and then transport us to a blue star. Right. Then we would not see colors in the blue because we can only see colors in the visible part of the spectrum. There'd be blue and violet, ultraviolet. We only see colors in the visible part of the spectrum. However, you can fake it, Authentically fake it.

[Neil DeGrasse Tyson]

That's called the perfect Instagram filter. Right.

[Paul Mercurio]

So going in that direction, we have violet. Take three bands in violet light that are adjacent to one another. Then once you do that, you assign rgb, bring them back together, and you can reconstruct what you would see if our sensitivity were shifted to the violet and ultraviolet part of the spectrum, to the blue part of the spectrum. So we should think of it as shifted color is what it is.

[Neil DeGrasse Tyson]

But we're only limited in how much we can. Our abilities to shift.

[Paul Mercurio]

We're very limited.

[Neil DeGrasse Tyson]

Well, you are, I'm not.

[Paul Mercurio]

So we see red through violet. That's it. And that's if I want to see color anywhere else. You take out the rgb, slap it down on three different bands, and out comes a color picture of X rays, of infrared, of ultraviolet, of gamma rays, all the above.

[Neil DeGrasse Tyson]

And so a red planet, a blue planet, a red star, a blue star. Is there any star with a color that you have the ability to see without sort of slapping that, doing that technique?

[Paul Mercurio]

Rbg.

[Neil DeGrasse Tyson]

Yeah, rbg.

[Paul Mercurio]

Roy. Say it. Roy G. Biv.

[Neil DeGrasse Tyson]

Roy G. Biv.

[Paul Mercurio]

So, no, just the way we evolved, we can't see into it. So, by the way, this band of visible light is very narrow compared with ultraviolet or infrared. Very narrow. So we're practically blind no matter what. And insects see into the deep ultraviolet. Insects. And perfectly happy.

[Neil DeGrasse Tyson]

When I stare into a very bright light and then I can't see for a second what's happening, that's a different thing.

[Paul Mercurio]

You, you, you overstimulate the retinal cells, which they have to recover.

[Neil DeGrasse Tyson]

Yeah. Which takes several seconds.

[Paul Mercurio]

Yeah, yeah, yeah.

[Neil DeGrasse Tyson]

Which is always fun, by the way, after you've been drinking. All right, another question. Hello, I'm John Mayhoy. There you go. From Parkland, Florida. I know that the cosmic microwave background is like a snapshot of the early universe and its temperature has been dropping ever since. So I'm wondering, could this temperature be used as a kind of universal clock? If we could measure it super accurately, would that tell us exactly how old the universe is right now? Would that age be the same no matter where you are in the universe?

[Paul Mercurio]

Yes, because every part of the universe was in the same place at the same time 13.8 billion years ago. So the oldest things in the universe in every direction you look are exactly the same age traceable to that period of time. So, yeah, everything now at this moment, we see in the past. So we can ask, what is that thing doing now? Well, it's even farther away from us. And we can think of the diameter of the universe as how big the universe is today. Even though you can't see that. And that diameter is coming in at 96, something like that billion miles full diameter. So if you could see those galaxies on our horizon today, that's what they look like. But that would need an infinite speed of light.

[Neil DeGrasse Tyson]

And that's.

[Paul Mercurio]

I'm not. We're not giving you that.

[Neil DeGrasse Tyson]

Why not possible not giving it to you.

[Paul Mercurio]

Observational limits on the universe and temperature.

[Neil DeGrasse Tyson]

Is the only way to measure this is to have a universal clock.

[Paul Mercurio]

Is temperature also works. Yeah. So as the universe grows, the temperature cools. So it's a one to one correspondence. So you can just backstrapolate to the early universe.

[Neil DeGrasse Tyson]

So there's a murder scene and they do a forensic.

[Paul Mercurio]

Why are you so morbid?

[Neil DeGrasse Tyson]

Well, because that's how my brain thinks. And they, and they. And so they can figure out based on the temperature of the body when the body died.

[Paul Mercurio]

Yes.

[Neil DeGrasse Tyson]

So that's what's happening there.

[Paul Mercurio]

I hadn't thought about it that way, but that's. That works.

[Neil DeGrasse Tyson]

Yeah. You got the crusty old cop and then you got the sexy sidekick.

[Paul Mercurio]

That's right.

[Neil DeGrasse Tyson]

Male or female?

[Paul Mercurio]

I haven't thought about that.

[Neil DeGrasse Tyson]

Well, that's why I'm here.

[Paul Mercurio]

What's the next question?

[Neil DeGrasse Tyson]

Okay. This is Joe Liparella from Pennsylvania. Relativity tells us that as an object approaches the speed of light or is in a deep gravitational well, time slows to a stop relative to other observers. My Question is, what is on the other side of that extreme? If an object is motionless and if there is zero gravitational effect on it, how would time work for that object?

[Paul Mercurio]

There's zero gravity. Then time goes fast for it.

[Neil DeGrasse Tyson]

Well, an object is motionless and if there's zero gravitational effect on it.

[Paul Mercurio]

Right.

[Neil DeGrasse Tyson]

So how would time work?

[Paul Mercurio]

When you are in the presence of gravity, you age slower.

[Neil DeGrasse Tyson]

So this is like the ultimate anti aging hack. This is. We should bottle this. We should be on QVC right now, not on this dog and pony show you call StarTalk. We could be making some big bucks.

[Paul Mercurio]

Start our own. Our own QVC channel.

[Neil DeGrasse Tyson]

Yeah, Dr. Tyson's QVC hack.

[Paul Mercurio]

So what are they asking then?

[Neil DeGrasse Tyson]

They're asking my question is what is on the other side of that extreme? In other words, relativity tells us that as an object approaches the speed of light, or is in a deep gravitational well, time slows to a stop.

[Paul Mercurio]

Okay, so now watch. So some years ago, people realized you couldn't accelerate past the speed of light. But does that preclude a particle existing faster than light? If you can't accelerate past it, can you exist on the other side? And serious thought was given to that. To the point where there's some movies based on it and there's a hypothetical particle that has these properties. It's called a tachyon. Tachyos, from the Greek meaning fast. Tachyos. Tachyons and tachyons would live backwards in time.

[Neil DeGrasse Tyson]

How is that possible?

[Paul Mercurio]

Because if time slows down as you reach the speed of light, on the other side of speed of light, if you continue the equations jumping that gap, time would go backwards. For it.

[Neil DeGrasse Tyson]

For it. For.

[Paul Mercurio]

Yes. Yeah, for it.

[Neil DeGrasse Tyson]

Do we know they exist?

[Paul Mercurio]

No, we never found them.

[Neil DeGrasse Tyson]

So then how could you have a theory about something that should.

[Paul Mercurio]

Because it's allowed to exist by Einstein's equations. And if something is allowed, that's good enough reason to go out and look for it if other parts.

[Neil DeGrasse Tyson]

But at one point do you stop looking in all seriousness and go, this doesn't. If you can't find it, welcome to.

[Paul Mercurio]

The frontier of science.

[Neil DeGrasse Tyson]

No, it's like I can't find my phone in my house. I'm not gonna keep looking. Go. I know it's there.

[Paul Mercurio]

We don't know. That's right. It's a mystery. But if you give up and someone else finds it a month later.

[Neil DeGrasse Tyson]

So when time meets an object with no gravity and no movement, it's like my lazy, good for nothing 15 year old son who won't mow the Lawn. Right. He just lays. Just sits there. So the answer to the question is yes. Or is it that clear?

[Paul Mercurio]

The answer is, weren't there two parts to that?

[Neil DeGrasse Tyson]

Yeah, there's the. An object approaches the speed of light or is in a deep gravitational well, time slows to a stop.

[Paul Mercurio]

Yes. In a deep gravitational well, yes. Time slows. Correct.

[Neil DeGrasse Tyson]

And what is on the other side of that extreme?

[Paul Mercurio]

And that would be Tachyons.

[Neil DeGrasse Tyson]

Tachyons, which we know there, but we haven't found them. Okay.

[Paul Mercurio]

Correct.

[Neil DeGrasse Tyson]

Got it.

[Paul Mercurio]

The technologies work in the equations.

[Neil DeGrasse Tyson]

So as a result.

[Paul Mercurio]

And so we're saying, well, right. All these other ways, maybe this prediction of the equation should work as well.

[Neil DeGrasse Tyson]

Got it.

[Paul Mercurio]

So if you are motionless in space, as far as you're concerned, you'll still have your own timeline. And all that matters is what other people will say of you as they fly by you. So everyone will have a different time reference for you, but all you care about is your own clock and your own wristwatch and your own clock on the wall. And that's all you care about. Now, that's if you're not moving. But if there's no gravity, then time speeds up for you.

[Neil DeGrasse Tyson]

So if an object is motionless and there's zero gravitational effect, how would time work for that object? This is where we're talking. So this is where we were joking about gravity anti aging hack. Right? So in other words, there'd be no aging because time, there's zero gravitational effect.

[Paul Mercurio]

Yeah, but. And everyone else around you in your same reference frame will age at exactly the same rate. It could be one second for every 10 seconds outside of your club. Right, but it won't matter to any of you. You can't hack that system and say, I want to go back to when I was younger.

[Neil DeGrasse Tyson]

Okay, but if you're so smart, tell me who in that group is going to get a plastic surgery first to avoid the aging process?

[Paul Mercurio]

Yeah. Plus, if you're in space with zero G, some surgeries aren't necessary.

[Neil DeGrasse Tyson]

No. Well, it's right because you got nothing pulling on you.

[Paul Mercurio]

Nothing pulling on you. Stuff floats.

[Neil DeGrasse Tyson]

That's what we should invent. We should invent people. 0G. Facial surgery. Impact confirmed.

[Paul Mercurio]

The Slayer has been activated. Demonic threat level increasing. Hold the line.

[Neil DeGrasse Tyson]

Everything will be destroyed.

[Paul Mercurio]

We need him. Our enemy is divided. Focus on breaking the humans. I can never rule so long as you are the only one they fear. All the power of hell Cowering before one man. ID Software presents Doom. The Dark Ages stand and fight to become the strongest super weapon of Gods and Kings in a Medieval war Against Hell. Available May 15 on Xbox, Series X and S, PlayStation 5 and PC pre order now.

[Neil DeGrasse Tyson]

Rated M for mature.

[Rob Lowe]

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[Paul Mercurio]

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[Neil DeGrasse Tyson]

We believe that shoes are an important part of, well, everything from first steps.

[Paul Mercurio]

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[Neil DeGrasse Tyson]

Forts to building a life. For all the big and small moments that make up your whole world.

[Paul Mercurio]

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[Neil DeGrasse Tyson]

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[Paul Mercurio]

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[Neil DeGrasse Tyson]

I like this question. It's very simple, straightforward, but interesting. Dennis Alberti, please explain. Buoyancy.

[Paul Mercurio]

Buoyancy. I love it. All right, so it's all about density. In the end of the day, it's about density and gravity, you know, so if you are. And gravity, yes. If you are less dense than the medium you're immersed in, you will float to the top. It's that simple. It's not more complicated than that.

[Neil DeGrasse Tyson]

Define density.

[Paul Mercurio]

It's how much matter you can cram into a certain volume. So the big advance, it's amazing. This didn't happen until the 19th century was there was some early variants in the 18th century, but it really took off in the 19th century. The fact that you could float metal, if you make a boat out of metal, then it's almost impervious to war.

[Neil DeGrasse Tyson]

Not icebergs and a billion dollar gross at the movies.

[Paul Mercurio]

It's exactly what Titanic did. It's probably up to 2 or 3 billion now.

[Neil DeGrasse Tyson]

Look, to summarize it, a submarine is a boat in denial.

[Paul Mercurio]

Well, so here's what happens.

[Neil DeGrasse Tyson]

So you should react to that. That was a good line. So a submarine is a boat in denial.

[Paul Mercurio]

So if you have a hull that's made of metal, any bits of that metal would just sink to the bottom. However, if it's in the hull shape, it's pressing down on the water, the water is rising up and you've created an environment that on average is less dense than water. And so Therefore, it floats because of the V shape, because most of the volume is air. So you get to add the air plus the metal as part of the contents. That's within the volume. And when you do that, you systematically reduce the density of the material. If you go back 1,000 years ago, people made boats out of wood, sensibly, because wood floats. So you make anything out of wood. It would float. That made complete sense. But you're susceptible to attack.

[Neil DeGrasse Tyson]

But if I took a metal plank, a 4 by 12 piece of metal flat, and threw it in the water, would that sink? Yes, because you don't have that V shape. You don't have the relation to air.

[Paul Mercurio]

Because it's all about volume. It's all about volume. So if you carve it into a volume, then it's the mass of the shell divided by the full volume of the whole thing. And that gets very low. It'd be lower than water. It'll just float.

[Neil DeGrasse Tyson]

It's the same principle why an iceberg can float. Because you've.

[Paul Mercurio]

Icebergs are just simply less dense than water.

[Neil DeGrasse Tyson]

Right.

[Paul Mercurio]

Simply less dense.

[Neil DeGrasse Tyson]

So you don't need that V shape for that to.

[Paul Mercurio]

For an iceberg. No, no, no. I mean, you don't ever need a V shape. Except that, I mean, like Styrofoam will make a boat, but it doesn't need a V shape.

[Neil DeGrasse Tyson]

Right.

[Paul Mercurio]

V shapes are important if you know the material you're working with is heavier than the stuff itself.

[Neil DeGrasse Tyson]

Right. Because you're display, you want to displace.

[Paul Mercurio]

Correct.

[Neil DeGrasse Tyson]

Right. It's all about displacement.

[Paul Mercurio]

Correct.

[Neil DeGrasse Tyson]

So the bottom line is icebergs float. You got a V shaped hull, steel float.

[Paul Mercurio]

Yes.

[Neil DeGrasse Tyson]

Styrofoam cooler. Best scenario, you can sit on it and tap in and get a couple of beers. At the same time.

[Paul Mercurio]

At the same time.

[Neil DeGrasse Tyson]

Okay. That's why I'm here.

[Paul Mercurio]

Paul. Got time for one more?

[Neil DeGrasse Tyson]

One more. Got it. Okay. This is. This is actually a very interesting one. Terry Burke from St. Louis. My question is simple. In nuclear fission and fusion, a small amount of matter is lost and converted to a large amount of energy. Is the gravity associated with the lost mass also lost?

[Paul Mercurio]

No, because. Great question, by the way. Gravity emanates not only from mass but also from energy, because mass and energy are the same thing, different sides of the same coin. So you're not just losing mass and not energy, you're losing some combination of the two, and they go hand in hand.

[Neil DeGrasse Tyson]

So the answer is no. Is the gravity associated with the loss?

[Paul Mercurio]

No.

[Neil DeGrasse Tyson]

And that can never vary. I mean, this is a constant. This can never. This. The idea that gravity associated with the lost mass is also lost.

[Paul Mercurio]

Oh. Matter and energy are one and the same thing, so they each distort the fabric of space and time. And that's all you need to know about it.

[Neil DeGrasse Tyson]

Okay.

[Paul Mercurio]

Mm. We will commonly think of matter distorting space, but if there's energy there, it will distort space as well and equals MC squared reminds us that they are two sides of the same coin.

[Neil DeGrasse Tyson]

The more the amount of energy is created, is the same amount of gravity lost? In other words, like the mass lost, is gravity associated with the lost mass is also lost. Do you lose more gravity the more energy that's created?

[Paul Mercurio]

If it leaves the system? Yes. You're losing. You're losing gravity anytime any matter or energy leaves the system.

[Neil DeGrasse Tyson]

No, I know, but doesn't it all change over time, you know, depending on the amount of energy that's created? The more energy that created, the more gravity is lost. No.

[Paul Mercurio]

Yes, but the. It's a lot of energy and a very small amount of mass, so I wouldn't lose sleep over it.

[Neil DeGrasse Tyson]

Well, listen, it's up to me what I lose sleep over. Just because you walk through life not caring about science the way I do, I can't.

[Paul Mercurio]

It is weird, though, that humans, for one third of a rotation of the Earth, are semi comatose. One last question. I'll do it.

[Neil DeGrasse Tyson]

One last. One quick one.

[Paul Mercurio]

Sound by.

[Neil DeGrasse Tyson]

Okay, Mark Learned.

[Paul Mercurio]

I used to have a bell here. I don't know what I did with it.

[Neil DeGrasse Tyson]

I'm Mark from Portland, Oregon. Is our solar system comprised of remnants from a single supernova or a collection of many, if many? I'm curious how our or any galaxy diffuses multiple supernovas together.

[Paul Mercurio]

Okay, so first, a supernova is a huge explosion, and its guts are just scattered everywhere. Just start with that. Then the galaxy rotates, as we say, differentially. So the inner parts complete a circle faster than the outer parts. This shears the gas clouds that have all been contaminated by the detritus of a supernova explosion. And you get a few rotations of the galaxy. This stuff becomes very well mixed. And the next generation of stars is gonna have all the ingredients from that last round of supernova explosions.

[Neil DeGrasse Tyson]

So it's like fertile ground for the next round.

[Paul Mercurio]

Yeah, got it all the way through.

[Neil DeGrasse Tyson]

All right, I think that's all our questions.

[Paul Mercurio]

Good questions. Wow.

[Neil DeGrasse Tyson]

Yeah.

[Paul Mercurio]

All right, we're done here. Yet another installment of Cosmic Queries with Paul Mercurio. But we'll find you. Your show on the road.

[Neil DeGrasse Tyson]

Yeah. Paulmicurio.com did someone say, take that show.

[Paul Mercurio]

On the road and then that's what you did?

[Neil DeGrasse Tyson]

I did it in New York, and then the authorities called and said, take it on the road. And Inside out with Paul McCurry. On my podcast.

[Paul Mercurio]

Is there a movie called Inside Out?

[Neil DeGrasse Tyson]

There is, but thanks for bringing that up. This is how you help me get people coming. Oh, yeah. You just copied something, so don't go see it. Yeah. Inside Out.

[Paul Mercurio]

Good interactions with the audience. You're very good on your feet in that way.

[Neil DeGrasse Tyson]

Yeah. My. My show, Permission to Speak is about sort of engaging the audience and their stories. It was born out of crowd work with an audience.

[Paul Mercurio]

Yeah.

[Neil DeGrasse Tyson]

Good audiences, but it's. But people have fascinating. And your podcast, Inside out with Paul.

[Paul Mercurio]

McCuri, which I've been on.

[Neil DeGrasse Tyson]

Yes. You've been on with Paul McCartney and Stephen Colbert and a lot of fun people, so.

[Paul Mercurio]

Well, I wasn't enough to.

[Neil DeGrasse Tyson]

You were. The only reason Paul McCartney did it is because he found out you did it.

[Paul Mercurio]

Oh, see, that's. That's what I expect.

[Neil DeGrasse Tyson]

And he knows a lot more about the theory of relativity than you do. Weird. I don't know, because I just thought he played music. No. Yeah. So hopefully people can check all that stuff out. Paul Mercurio.com for it.

[Paul Mercurio]

You got it. All right. This has been startalk, Cosmic Queries, Grab Bag Edition. Neil Degrasse Tyson here thanking Paul Mercurio. As always, I bid you to keep looking.

[Neil DeGrasse Tyson]

Foreign.

[Rob Lowe]

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[Neil DeGrasse Tyson]

I'm Neil, founder of Klear. When I found ceramics, I realized my calling was to give others the space to be creative. So I set out to open my own studio. Having a Chase Ink card has allowed us to grow and bring people together. Now we're molding a creative community. Chase Inc. Business Cash Card. You can earn up to 5% cash back on business essentials so your business.

[Paul Mercurio]

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[Neil DeGrasse Tyson]

Make more with yours.

[Paul Mercurio]

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[Neil DeGrasse Tyson]

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[Paul Mercurio]

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