Deciphering Gravitational Waves, with Janna Levin

Summary

Podcast Summary: Deciphering Gravitational Waves with Janna Levin – StarTalk All-Stars

Podcast Information:

• Title: StarTalk Radio
• Host/Author: Neil deGrasse Tyson
• Episode: Deciphering Gravitational Waves, with Janna Levin – StarTalk All-Stars
• Release Date: December 20, 2024
• Description: Science, pop culture, and comedy collide on StarTalk Radio! Neil deGrasse Tyson, astrophysicist and Director of New York's Hayden Planetarium, alongside comic co-hosts, guest celebrities, and scientific experts, explore astronomy, physics, and the mysteries of life in the universe.

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Introduction

Jana Levin kicks off the episode by warmly welcoming listeners to StarTalk All Stars. She introduces the co-host, Matt Kirshen, host of Probably Science, and the esteemed guest, Ray Weiss, Professor Emeritus from MIT and one of the original architects of the LIGO (Laser Interferometer Gravitational-Wave Observatory) detector, which famously announced the detection of gravitational waves earlier that year.

Understanding Gravitational Waves

The discussion delves into the nature of gravitational waves, a concept rooted in Einstein's theory of general relativity. Ray Weiss explains:

"Gravitational waves are a traveling distortion of space and time... It's a stretching of space in one dimension and a compression in another as the wave travels perpendicular to its direction" (07:30).

Jana Levin highlights the public fascination with the discovery, noting how it captured global attention but also puzzled many about its true significance.

Historical Journey to LIGO

Ray Weiss recounts his early days at MIT, grappling with the complexities of general relativity and the skepticism surrounding gravitational wave detection. Faced with funding challenges post the Vietnam War era, Weiss describes how initial support from the military dwindled, hindering his research efforts.

"Nobody thought you were going to succeed. They thought you were wasting your time." (13:06)

The conversation shifts to Joe Weber's early, albeit controversial, attempts to detect gravitational waves in the 1960s, which garnered significant attention despite lacking definitive evidence.

Formation and Development of LIGO

The pivotal moment in the narrative is the collaboration with Kip Thorne, a theoretical physicist whose unwavering belief in the existence of black holes and gravitational waves galvanized the LIGO project. Ray Weiss emphasizes Kip's role in lending credibility and scientific rigor to the endeavor.

"Kip was the reason... he gave it a certain cache. He showed people that it was possible." (31:15)

Together with Ron Drever from Scotland, the trio initiated the development of LIGO in the early 1980s. Weiss describes the immense technical challenges, including achieving the unprecedented sensitivity required to detect gravitational waves, which manifest as minuscule distortions in spacetime.

"The amount of motion the gravitational wave induces is proportional to the size of the system... in our case, the first one was too big." (27:29)

The Breakthrough Discovery

On September 14, 2015, LIGO made history by detecting gravitational waves emanating from the collision of two black holes approximately 1.3 billion light-years away. Ray Weiss shares his astonishment upon reviewing the data:

"It was an absolutely magnificent curve... it was this binary black hole, three solar masses. That's got to be a fake." (47:37)

The subsequent verification confirmed the monumental discovery, marking a new era in astrophysics and affirming Einstein's predictions over a century later.

Implications and Future Prospects

The detection of gravitational waves opens avenues for exploring cosmic phenomena that were previously invisible to traditional telescopes. Ray Weiss discusses potential sources of gravitational waves, including neutron stars and other black hole mergers, and the technical advancements needed to observe lower-frequency waves through projects like LISA (Laser Interferometer Space Antenna).

"Once they're very far apart... we can begin to contemplate." (44:26)

Cosmic Queries: Listener Questions

In the Cosmic Queries segment, Jana, Matt, and Ray address listener-submitted questions:

1. Time Travel and Gravitational Waves

   • Jana Levin: "Do gravitational waves help us travel in time?"
   • Ray Weiss: "I don't think so. But you can always travel to the future by moving in space-time, like traveling to a black hole and coming back." (14:45)

2. Effects of Gravitational Waves on the Earth

   • Question: "Would gravitational waves from nearby events affect humans or the planet?"
   • Ray Weiss: "If a black hole collision occurred within our solar system, we would feel it as a stretching and compressing force." (15:58)

3. Speed of Gravitational Waves

   • Question: "Can gravitational waves travel faster than light?"
   • Ray Weiss: "Our observations show gravitational waves travel very close to the speed of light." (34:15)

4. Gravitational Waves and the Double Slit Experiment

   • Question: "Are there plans to conduct the double slit experiment using gravitational waves?"
   • Ray Weiss: "It's extremely challenging due to the weak nature of gravity. Current technology doesn't allow for such manipulation." (35:46)

5. Gravitational Waves Reflecting Light

   • Question: "Do gravitational waves reflect light, potentially creating images?"
   • Ray Weiss: "Gravitational waves interact with light by creating sidebands, but they don't reflect light in a way that would form images." (52:23)

Conclusion

The episode wraps up with a reflection on the monumental achievement of LIGO and the ongoing quest to understand the universe through gravitational waves. Jana Levin and Matt Kirshen express their gratitude to Ray Weiss for sharing his invaluable insights and experiences.

"It's been a great show today. Ray, always an honor. Thank you for having me." (52:49)

Key Takeaways:

• Gravitational Waves: Ripples in spacetime caused by massive cosmic events, confirming Einstein's general relativity.
• LIGO's Journey: Overcoming skepticism and technical hurdles to achieve the first detection of gravitational waves.
• Scientific Impact: Opens new methods for observing and understanding the universe's most enigmatic phenomena.
• Future Endeavors: Projects like LISA aim to detect lower-frequency gravitational waves, expanding our cosmic horizons.

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Notable Quotes:

• Ray Weiss on Gravitational Waves:

  "Gravitational waves are a traveling distortion of space and time... It's a stretching of space in one dimension and a compression in another as the wave travels perpendicular to its direction." (07:30)

• Ray Weiss on LIGO's Initial Challenges:

  "Nobody thought you were going to succeed. They thought you were wasting your time." (13:06)

• Ray Weiss on Kip Thorne's Contribution:

  "Kip was the reason... he gave it a certain cache. He showed people that it was possible." (31:15)

• Ray Weiss on Discovering Gravitational Waves:

  "It was an absolutely magnificent curve... it was this binary black hole, three solar masses. That's got to be a fake." (47:37)

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Timestamps:

• 07:30 - Explanation of gravitational waves
• 13:06 - Initial skepticism towards LIGO
• 31:15 - Kip Thorne's role in LIGO
• 47:37 - Discovery of gravitational waves

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Keep Exploring the Cosmos and Stay Curious!

Transcript

[Ray Weiss]

Now.

[Jana Levin]

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[Jana Levin]

Rated M for mature. Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now. Welcome to StarTalk All Stars. I'm Jana Levin, your All Star host for the day. I'm an astrophysicist and author. Joining me as co host is the funny Matt Kirschen, host of Probably Science.

[Matt Kirshen]

Hi Matt, how's it going?

[Jana Levin]

Welcome back.

[Matt Kirshen]

Thanks for having me back.

[Jana Levin]

It's been like 10 minutes.

[Matt Kirshen]

Yeah, it's nice to be here in space.

[Jana Levin]

It's great to have you. And I also want to introduce one of my favorite people in the world joining us in the studio, Ray Weiss. Thank you, Jonathan, otherwise known as Rainer Weiss for long. Great to have you. Ray is professor emeritus from mit. He is also one of the original architects of of the LIGO detector which announced the detection of gravitational waves last year. It was this year. Why does the prompt say last year?

[Ray Weiss]

Well, it happened last year.

[Jana Levin]

It happened last year. Sorry guys. This year it was one of the most groundbreaking discoveries of modern astrophysics and very personally important to me. Ray is one of the founders of the LIGO instrument and continues to work on the instrument all the time. As I know because I've been to the sites with you. You kindly let me perform the tunnel. I remember, yes. In the heat of Louisiana it was amaz. So it's so great to have you here. We're going to talk about LIGO and gravitational waves and black holes. So I think what we want to draw out is why this discovery was so important. I think that when people heard about it, it was so the whole world stopped in February 11th when the announcement was made. And for a minute it was so exciting. Everybody was frozen. And then I felt like an hour later people just weren't sure what it was all about. It's hard to understand.

[Matt Kirshen]

I mean, I've got it covered because I'm obviously good on these things. But just for everyone else, if you could just kind of give a vague overview.

[Ray Weiss]

I'll try. But I was as mystified as you in the fact that it had this enormous public recognition.

[Jana Levin]

Oh yeah.

[Ray Weiss]

I mean you take other things.

[Jana Levin]

Were you surprised someone made the one?

[Ray Weiss]

I was more than surprised. I was flabbergasted, to be honest with you.

[Jana Levin]

Oh really?

[Ray Weiss]

I mean my first real instinct that it had permeated the society was when I came to New York to come and visit you at the airworks and I get in the subway and there's this sign that says, you know, scientists can find gravitational waves, but you can't find an apartment in New York with a walk in closet. I said, where in the hell does that come from? You know? Exactly.

[Jana Levin]

It was a jeopardy question.

[Ray Weiss]

Is that what it was?

[Jana Levin]

Okay, yeah. No, also as well.

[Ray Weiss]

Oh, I didn't realize that. I didn't realize that.

[Matt Kirshen]

Have you has science now detected an apartment in New York with a walk in closet.

[Ray Weiss]

I haven't been looking lately. I don't live here.

[Jana Levin]

If anyone can find it, Ray can. So, Ray, do you want to tell us what gravitational waves are? Because this is very hard for people to understand. They can say the words, but they really don't get what it's all about. And they certainly don't get why you played it to them as a sound.

[Ray Weiss]

Well, let's start with what they might be. I mean, what they are, they're a result of Einstein's first thinking about how you measure things in space and time. In other words, he realized back in 1905 that the Newtonian theory we had, the theory that was the theory that was we all learned in high school was inadequate, that you couldn't have things travel so fast that everybody knew about it instantaneously. There had to be some delay because the fastest that things can move, even information thought, is the velocity of light.

[Jana Levin]

Right. So if the sun disappeared tomorrow, it should take us eight minutes.

[Ray Weiss]

Well, that's right. If the sun disappears, well, yeah, it'll take about eight, nine minutes before we really know about it. It's great.

[Matt Kirshen]

If you're like a magician or something.

[Jana Levin]

Do you need the extra time?

[Matt Kirshen]

Yeah, because like Quanta made the Statue of Liberty disappear, but he had like seconds really to do that in.

[Jana Levin]

Yeah, if you had 8 minutes to play with, you could do anything. Anything.

[Matt Kirshen]

You could be an amateur magician still kind of like you'd have time to get some helpers to actually shove it out of.

[Jana Levin]

What'd you do with the sun Met.

[Ray Weiss]

Yeah, but those eight minutes are damned important because they tell you that there has to be some mechanism for information to travel not infinitely quickly.

[Jana Levin]

Right. So in Newton's theory would have to be.

[Ray Weiss]

That's the first order way of talking about gravitational waves and specifically what are they. Einstein had a different way of looking at gravity than Newton did. And he taught us all that space and time get distorted by gravity. You get curvatures, you get distortions of space and time. And what a gravitational wave is, is a traveling distortion of space and time. But we measure it as a distortion in space. And the very special thing so you don't have, you can imagine what it is, it's not very hard to imagine is that it's a stretching of space and a compression of space. And here's, just bear with me, here's what it is where the wave travels, let's say toward you and it does its dirty work perpendicular to the Direction in which it's moving. So something's doing this. And while it's doing this, in which.

[Jana Levin]

It'S oscillating his hands in and out.

[Ray Weiss]

Oh, yeah, I got. That's right.

[Matt Kirshen]

Waving my hands back almost like a slinky spring.

[Ray Weiss]

Well, a Slinky. Let's say a Slinky in the X direction. But a Slinky inverted in the Y direction, it's doing the opposite. I hope you all use coordinate systems in one dimension. In the direction it's moving, perpendicular direction it's moving, it's stretching in one dimension, it's compressing in the other. And that continual compression expansion travels at the velocity of light toward you. And that's the way to imagine a gravitational wave.

[Jana Levin]

Now, when you first started thinking about this, you were a young professor at mit and you had this whole gravity research program. And I know you confessed to me that they asked you to teach a class in general relativity.

[Ray Weiss]

Well, I'll confess again. What Janet's referring to is a very big embarrassment. See, I come to MIT having been to Princeton, the hotbed of general relativity and gravity. And I come and I start a group very expendable. I'm an experimenter. I'm not a theorist like Jana. Jana is a true theorist, but I'm mixed parameters. I deal with things with my hands.

[Matt Kirshen]

And already, like before the show even.

[Jana Levin]

Started, he was using his hands.

[Matt Kirshen]

Well, before the show started, you were kind of looking at the microphone and, like, taking it apart. Like you can't help yourself with the switchboard.

[Ray Weiss]

Yeah, you gotta do that. You gotta find out what you're. What's. What you're surrounded by. Come on.

[Jana Levin]

That's part of the world. Yeah, palpate. Palpate the world.

[Ray Weiss]

So, you know, it's tactile and it's all sort of seeing things. But anyway, so as Jana says that, what happened is that I'm running this group that is supposedly about very complicated topics like cosmology, which is the history of the universe and also gravitation. Okay? Those were the two things I started. And then the department head comes to me and says, you know, we would like you to teach a course in general relativity, which is a course of the new kind of gravity. And I couldn't tell him. I didn't know a damn thing about it. I mean, I really didn't know much about it. I didn't know the mathematics. I mean, the students, when I finally started teaching were probably barely. I was barely half a day ahead of the students, if at all. So here I. And they asked me a very hard question as we go along. The course has its ups and downs, as you can well imagine. And they asked me a hard question. They said, look, what is a gravitational wave? And I try to answer it, but what was going on at that time was that Joe Weber, who was a physicist at the University of Maryland, had begun to talk about that he might have discovered gravitational waves.

[Jana Levin]

And this would have. His chemistry started in the 50s to.

[Ray Weiss]

No, this will start in the 60s, the late 60s. Well, it started really quite early in 62. And he made the announcement that he had discovered gravity waves in 1969. That caused a tremendous furor.

[Jana Levin]

It was incredibly famous.

[Matt Kirshen]

Well, yeah, and he was lying. He was just flying.

[Ray Weiss]

No, no, no, don't say lying. That's not the right word.

[Jana Levin]

We're all very defensive about Joe.

[Matt Kirshen]

Now, I don't want to brag, but I also did discover gravitational waves like about a month before you guys.

[Ray Weiss]

That's good. I'm glad of that. What did yours look like?

[Matt Kirshen]

It was just like. It was like I just put a cup on a table.

[Jana Levin]

It kind of wobbled a bit and water wobbled. And he knew that they were gravitational waves.

[Matt Kirshen]

It's Jurassic Park.

[Ray Weiss]

Like those two birds in the New Yorker cartoon. Probably saw that cartoon, didn't. Two birds sitting. This is right after the discovery. Again, two birds sitting on a branch. It was on the 12th of February, we announced on the 11th of February. So somebody had prior information. But these two birds, two birds are looking, one looking at the other and for one says, hey, did I hear you? Or was that a gravitational wave change in that case already? That's the kind of thing. Anyway, so let me get back to the story. The thing was that they asked me about this and I frankly, be honest with you, despite having trouble with the mathematics, I also had trouble with understanding Weber's experiment. It's not that he was lying or anything like that. It's just a way too complicated for me to understand exactly what he was doing. So I spent a lot of time one night thinking about how could I explain what a gravitational wave does and how would you detect it in the most pristine, simple minded way possible. And that's where this haiku, as you call it, came about, which is the. I thought, well, no, one way to do it is send some masses out there, put them out in outer space, put clocks on them, two clocks, one on one clock on the other, and have a light beam go from one to the other and measure the time. That's all. Yeah, very straightforward. Measurement.

[Jana Levin]

And they'd have to be sort of floating.

[Ray Weiss]

So that floating out there, they're bobbing.

[Jana Levin]

On the wave of the ocean. If something happens, well, they're actually just.

[Ray Weiss]

Moving along without any forces on them. And then all of a sudden a gravitational wave comes along and it changes the time that light takes. That goes between them. That's. It makes it shorter for a while and longer. Does exactly what the gravitational wave.

[Jana Levin]

But you started to build one.

[Ray Weiss]

Well, yeah, yeah, but that's the basic idea. And by the way, that idea is the one that propagated into the later on LIGO and everything else.

[Matt Kirshen]

Is this what you wrote about in your book? Is this what.

[Jana Levin]

Yeah, so I was fascinated with. You mentioned Ray looking at the microphones and all this stuff. I was fascinated that Ray said that he started life with one ambition which was to make music easier to hear.

[Ray Weiss]

That's right.

[Jana Levin]

And then you dreamt up which is basically a cosmic recording device. This sort of insane gigantic cosmic recording device to record sounds from space.

[Ray Weiss]

She was the only one in my whole life who ever made that analogy. And she. She was right, you know, I mean, I told her the story. Awesome. Because I think you have a musical background or around you is music and understood this right away. Yeah, but it's absolutely true. It was.

[Jana Levin]

Yeah. So what's the book called? Black Hole Blues and Other Songs from Outer Space. Which if I was Neil DeGrasse Tyson, I would say in an awesome deep DJ voice. I think I do have him recorded saying it. I should air it.

[Matt Kirshen]

Just play that in at that point.

[Jana Levin]

Right, exactly. Just right. Edit that in. But so you. This is. Okay, early 70s now we're talking. Talking about. Okay, so that's 50 years ago. And you started to build the first machine. But it was really quite small. And as I remember, you got a lot of flack for it because nobody thought you were going to succeed. They thought you were wasting your time.

[Ray Weiss]

I was worse than that. This is sort of an interesting epic in the whole history of the field. Yes. I got some money from the military, by the way, was funding my research. At the one time military support was very, very good. You know, it was. Had no onus associated with it in a society. And what happened was that they supported this. And what happened? I got about $50,000 to build a small prototype. And then all of a sudden everybody got very disenchanted with the military when the Vietnam War happened. And the funding for this.

[Jana Levin]

There goes your funding.

[Ray Weiss]

Funding stopped because the military was only supposed to support those things that were Relevant to its mission. And gravitational waves weren't quite in the military's complement of things they had to worry about. Right, so.

[Matt Kirshen]

And how can we use gravitational waves to kill our enemy? Like, how can we.

[Ray Weiss]

Well, if it gets there, I'll tell.

[Jana Levin]

You later than segment three.

[Ray Weiss]

If you care to pursue this. If you want to pursue this, I'll tell you later.

[Matt Kirshen]

Or at least just to, like, upset someone. Like, how can I use it to upset a neighbor? Like, my neighbor's playing music too loud.

[Jana Levin]

I'm gonna send gravitational waves towards them full blast.

[Matt Kirshen]

We're now the master of gravity, right? That's what we're dealing with here.

[Jana Levin]

Well, we're gonna come back. We're gonna come back to this discussion. But before then, I think it's time for us to take some cosmic queries. So if you are out there in the Ethereum, send us your messages. It's too late now. Of course it is too late.

[Matt Kirshen]

Well, is it?

[Jana Levin]

I don't know. It depends if we can time travel. Can gravitational waves help us? Time travel? You know what?

[Matt Kirshen]

Might as well ask this question then. This is perfect unintentional timing here. But Jake, the guy on Instagram is asking, does any of this mean I can travel in time?

[Jana Levin]

Ray, do gravitational waves help us travel in time?

[Ray Weiss]

I don't know how they would, but maybe you have an idea. You're a theorist.

[Jana Levin]

I don't think so. I don't think so. I can't think of a way in which they would help us travel in time. But, you know, you can always travel to the future. I mean always. If you have, though we're down here right now. I can travel towards your future, though. That's pretty weird. I could travel to a time when you are 15 years older and I'm only like a couple months older.

[Matt Kirshen]

Okay, by going off to space and coming back.

[Jana Levin]

Yeah, I can, you know, send you far from the Earth, or I can go to a black hole or something like that. So I can always travel to somebody else's future, but. But traveling to the past is the hard part. That's pretty tricky.

[Matt Kirshen]

All right. Taylor from Eugene R. We did a.

[Ray Weiss]

Fairly lousy job of answering him. All I did was a good nub.

[Jana Levin]

Yeah, I'm pretty sure Ray just said I gave a lousy answer.

[Ray Weiss]

You didn't give a lousy answer.

[Jana Levin]

And there's only one person in the world I would take that route.

[Ray Weiss]

Probably wanted something very deep.

[Jana Levin]

It was deep. You just weren't paying attention.

[Matt Kirshen]

So Taylor from Eugene, Oregon asks, do gravitational waves have Any direct effect on the physical environment. For example, if an event causing gravitational waves occurred close enough to Earth, would it have any discernible effect on humans or the planet?

[Ray Weiss]

Well, that's a question I can even answer. And in fact, if we measured this event from two black holes, and I have to start that way, which was, fortunately for us, 1.2 billion light years away, but had we been, let's say, within a few tens of years of that, we would have measured something. And you would have measured exactly what we measure in our detectors. You wouldn't stretched in one dimension and then compressed in the other dimension. You would have felt that.

[Jana Levin]

Now, we resist stretching and compression, but our, you know, auditory mechanism is designed to resonate in response. Do you think that we could technically hear a gravitational wave even in the absence of air?

[Ray Weiss]

I think that's not.

[Jana Levin]

Because it's saying this for months. Well, I don't think it's true.

[Ray Weiss]

Well, I think. Let's get to that issue right away because we, not you, we have generated some confusion by saying, listening to the universe, which is what a lot of people have said about this, and it's true. But it's not necessarily a sound wave that's exciting us, you see. And what is happening is that we are seeing these stretchings and compressions. And that's certainly going on in your ear, too. The compression and extension, even for that one mile, one year away, light year away, is still too small for your ear.

[Jana Levin]

Right. So how close do you think? Oh, yeah, I would agree with you.

[Ray Weiss]

If you got close enough, you would.

[Jana Levin]

But if you got close enough, you.

[Ray Weiss]

Would feel over your whole body and you might hear something. But that's not what we're doing.

[Matt Kirshen]

What we're doing, a sound wave is like the compression and expansion of the air around you.

[Ray Weiss]

That's right.

[Matt Kirshen]

This is the actual space itself is doing that.

[Ray Weiss]

Yeah, but be careful. What it is, is space. You're right. Space is doing the expansion and the compression. On the other hand, our instruments, this is where it gets converted into sound. That's why I looked at your microphone is what we do is we have a device that measures these very tiny displacements. We're using light and the timing of light, but then we convert that into a sound by amplifying it. And then that gets put into a loudspeaker. Yes, and then it makes a sound. Look, the important.

[Jana Levin]

It's a lot like an electric guitar.

[Ray Weiss]

Exactly. But exactly like an electric guitar. You've got a very good analogy. Very good analogy. And the other thing Is that it's an. The other piece of it is that this phenomena. These phenomena we're seeing. Phenomena we're seeing are things that have the frequency of our auditory system. That's the nature is making things with frequencies that run from the bottom of the piano to the top of the piano.

[Matt Kirshen]

And that's just by chance.

[Ray Weiss]

Well, that's because the things we're looking at. Well, it's little more than that. What it is is our instruments only sensitive in that band. Okay. Okay. And on top of that, nature's kind enough to give us something that does its wiggling and expanding and contracting and accelerating in that frequency band.

[Jana Levin]

A couple of black holes collide. They happen to ring spacetime in the human auditory frequency. Exactly.

[Ray Weiss]

Okay, so it's not sound waves traveling through space. I just don' Want to have that.

[Jana Levin]

It's like an electric guitar string is not a sound wave.

[Ray Weiss]

Wonderful analogy for people.

[Jana Levin]

But you had to build ligo to build the body of the guitar to record the shape.

[Ray Weiss]

Absolutely.

[Jana Levin]

Of the wave.

[Ray Weiss]

That's a beautiful analogy.

[Jana Levin]

Excellent. And then we're going to all break out into air style guitar. Give us another cosmic theory.

[Matt Kirshen]

From Florida, Sarah Garvi Jansa is asking, when gravitational waves are recorded, is there a way to know which black holes collided to make them? And is there any other event out there that could cause gravitational waves? If so, how would they differ?

[Ray Weiss]

Boy, that's a profound question. This has a lot of different pieces to that question. Let's first of all say how do we know that we are even seeing black holes? I think that's one way in our experiment that we were seeing black holes. You have to do an analysis to find that out. It could be other systems that, you know, neutron stars. There are many, many things that oscillate and wiggle that can make gravitational waves. But it happens to be. And this is the important thing, the specific wiggles we saw when you solve them as trying to figure out what the motions are that made those wiggles. You wind up with masses that are. In our case, the first one was too big. The masses are 30. Each one of the masses was about 30 solar masses. And we don't know of things. We know of ordinary stars that do that, but they're too big. Because what happens if you take an ordinary star that might be big?

[Jana Levin]

It was surprising how big they were.

[Ray Weiss]

They were.

[Jana Levin]

It was surprising how big they were. Yeah.

[Ray Weiss]

But monsters are exciting. They're monstrous. I mean, all the black holes people had seen or not. Nobody's seen a black hole but had evidence for was around 10 solar and smaller around there. No, the important thing is that once you make the calculation that you know, it's about 30 solar masses that are jiggling around, you then say, my God, look how close they are. From the equations, you can say they're much closer than any star. They would be inside of each other.

[Jana Levin]

Yeah, they're a couple hundred kilometers across.

[Ray Weiss]

These things are no bigger than just the size of Connecticut maybe, you know, and, or even smaller.

[Matt Kirshen]

Maybe the only things that big that can also be that close at black holes.

[Ray Weiss]

Well that's the argument. That's fundamentally the argument.

[Jana Levin]

That's the best we can do.

[Ray Weiss]

Exactly the argument.

[Jana Levin]

So maybe there's something else that when we got close we realized didn't have an event horizon, wasn't a complete shadow, wasn't really empty space time that, you know, it can be different than what we think of a black hole as, but it's gotta be heavy and small. Running a small business takes endurance, determination and the right support to reach your goals. And MasterCard is here to help fuel.

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[Ray Weiss]

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[Ray Weiss]

Wilson and I support StarTalk on Patreon. This is StarTalk with Neil DeGrasse Tyson.

[Jana Levin]

When you were talking about in the last segment running out of funding because the military funding was cut, and you told me the next big event is. I met Kip. I love that line. Let me tell you what the next event was.

[Ray Weiss]

The next event was really trying to get money. That was the next event to try to finish it. And that's what happened. Kip comes soon. But the next event was really trying to get some money. And that's where I ran into the trouble. Said there were trouble getting that money, getting that. People were skeptical.

[Jana Levin]

Your instrument was a meter and a half apartment?

[Ray Weiss]

Yeah, the initial prototype, it was a meter and a half. If we wanted to just demonstrate it was never intended to make a detection. In fact, nothing until LIGO was even ever able to contemplate making a detection.

[Jana Levin]

Somebody tell you I could do better by looking out the window? If the sun blew up, you couldn't detect it?

[Ray Weiss]

Yeah. Well, one of my graduate students, the first time I ever put a graduate student on the project, had a terrible time with his. With. With my colleagues because they had no measurement of a real scientific result. They had a beautiful piece of technology, but that's not what you get a PhD for in Physics necessarily. But let's get away from that, because you asked the question. So what happened is they the. I tried to get money and I didn't. And what happened is the. The National Science foundation, which is what they do, always sends proposals to everybody who knows something about this. And what they did is they sent it to Europe. And the Europeans don't have quite the same mores about an American proposal. And I had a very interesting conversation with a guy from the Max Planck Institute.

[Jana Levin]

This is after your grant was declined.

[Ray Weiss]

Yes. Oh, yeah, that's right.

[Jana Levin]

Yeah, it was declined. So here you are with no money.

[Ray Weiss]

Yeah, yeah. Here in 1975 or so. We had started building the thing in 72, and I was trying to finish it. And so we got this wonderful call from a guy at the Max Planck, and he says, you know, we've been working on Weber bars. We didn't see anything. And by the way, they had done a beautiful job of not seeing anything.

[Jana Levin]

Right.

[Ray Weiss]

Sometimes not seeing something is better than seeing something, especially if it's in that.

[Matt Kirshen]

Case or like, if you're talking about my dancing, it's better to not see. You're not see. Every scientist will tell you that.

[Ray Weiss]

So. Because you make confusion if you see something that's there and that's not supposed to be there. And so there are a lot of.

[Matt Kirshen]

Things there that are not supposed to be there.

[Ray Weiss]

So what happened is very good. So what they did is they asked me if they would mind if they would work on this. They thought it was a good idea. I said, how can you mind? And they asked me if I had a graduate student I could send them or somebody that had been working on this.

[Jana Levin]

Here they are. They're kind of pulling ahead on your idea.

[Ray Weiss]

Oh, they pulled way ahead.

[Jana Levin]

They pulled ahead on your idea. They had funding.

[Ray Weiss]

They had funding and they were very good. Besides, give them credit, they were superb. And that also started my colleague Ron Drever in Scotland, who also was doing Weber bars of a different kind. And then he got interested in this. And both of those groups, I just have to say it and make sure people hear it. They both did a spectacular job of making the thing better, the idea better, and getting the thing working. So that's after that is when I met Kip.

[Jana Levin]

Right. So eventually it becomes you, Kip. And this is now fast forwarding 10 years. UKIP and Ron Drever become the three, the troika that initiate the development of LIGO. It even gets a name. It finally gets a name in, like 1985. It didn't have the name before. Laser Interferometer Gravitational wave observatory.

[Matt Kirshen]

So LIGO started 30 years ago.

[Ray Weiss]

It started well, LIGO started really now it's a little earlier than that in 83. Because what happened is we did a study. This is like Kip getting to Kip has a little prelude to it.

[Jana Levin]

Yeah.

[Ray Weiss]

I couldn't get the money for the prototype. Eventually I got some money, but I decided by looking at the wonderful work that had been done in Europe, that I was not going to be in such a hurry to finish the prototype, but rather I would rather do a study to find out what it really would take to build a LIGO.

[Jana Levin]

Right. So here you had a 1.5 meter machine, and how big did you decide it had to be?

[Ray Weiss]

It had to be. Well, we started studying and I did a whole study of it. It looked like it had to be over a kilometer. And if I wanted to do 10,000 fold. Yeah. Well, I want to do tend.

[Matt Kirshen]

Like something that was about like, yay big.

[Ray Weiss]

That's right.

[Jana Levin]

Yeah. Arm span to it doesn't fit on the MIT campus or even in Cambridge, Massachusetts anymore.

[Matt Kirshen]

Most of my experiments like the size of a matchbox.

[Jana Levin]

Right. They involve.

[Ray Weiss]

Nowadays they even get smaller, you know, these nanotechnology things. But you can't do gravitational Wave for that wave. Why you can't do it? Because the amount of motion is bigger. The amount of motion the gravitational wave induces is proportional to the size of the system. See, what's constant in a gravitational wave is the strain. That's getting a little technical. That's the ratio of the added displacement, the compression or expansion of the gravity wave divided by the distance that the objects are already apart. And that number, that ratio is a constant.

[Jana Levin]

Yeah, it's very small. So LIGO now has these mirrors suspended at the corners of This L shaped 4 kilometer long. Two instruments on two different coasts, one in Louisiana, one in Hanford. By how much are the mirrors displaced? You're describing that. That's the same kilometers. I can translate.

[Ray Weiss]

You can Translate? Well, it's 10 to the minus 18.

[Jana Levin]

Meters, which is a trillion.

[Ray Weiss]

Okay, you like that? Fine.

[Jana Levin]

A millionth of a trillionth of the size of the arm. So over four kilometers, it's very small. Which is how it's like.

[Ray Weiss]

Well, no, it's 10 to the minus 21 is the strain and it's 10 to the minus 18 is the amount of motion in a 4 kilometer arm.

[Jana Levin]

Right. So that comes to about a 10,000th of the width of a proton.

[Ray Weiss]

Exactly. Yeah, that's exactly.

[Matt Kirshen]

If you had to convince who to let you build this?

[Ray Weiss]

Well, a lot of people. And that was the thing, you see when you tell. Tell somebody you're going to measure, tell an engineer, I mean a solid, well rounded engineer, that you're going to measure something at 10 to minus 21, which is really the right number to use because that's what the gravitational field strength is. They look at you like you were sort of a madman. And you know, I mean, nothing gets measured at that 10 to minus 21. So that's the first problem you have. The second problem you have is you got a nut like me trying to convince some heavy that, you know, you can do this right now. Why should they trust me? That's the other problem. I have no recommendation for this.

[Jana Levin]

Well, plus people weren't even sure there were black holes out there. For a large part of your initiative.

[Ray Weiss]

And what Jana just hit is the fundamental problem. Not really the fundamental problem that we had, which was nobody could tell us how much. What were the sources? So now we have three. A triple go. That's really bad. A triple. No, let's put it that way. An insanely small number. A guy who's a little bit of a flat driving it.

[Jana Levin]

You think that would be you? Yes, I'm afraid so.

[Ray Weiss]

And then nobody can attest that there's real sources. And people at mit, where I was a faculty, saying black holes didn't exist. See, that was a whole backdrop of this as well.

[Jana Levin]

You're trying to persuade them to spend.

[Matt Kirshen]

Money to detect the effects of something that they don't think exists.

[Ray Weiss]

That's right. And it's a lot of money. 100 million bucks about.

[Jana Levin]

Well, Ray, you didn't know that they existed either. I mean, you didn't know. So what possessed you to keep going? I mean, it is insane.

[Ray Weiss]

Well, I'm giving you a very silly, silly answer, which is the truth. Okay, a really silly answer. You think I'm a really profound scientist. That's baloney. But I enjoyed the work and I enjoyed the people. And that was what drove it. I hate to tell you that. It was interesting work to do.

[Jana Levin]

I think that's a great thing for people to understand. Scientists do what they do because they love it. Not necessarily out of ego satisfaction.

[Ray Weiss]

No, the end result was. It was an interesting result. Could we get such a result? It was a good gamble to take. But that wasn't the thing that drove me. I had to tell you that.

[Matt Kirshen]

It is something that I get because like when I'm doing my experiments on the effects of paint, drinking on blindness, it's not the glory. I'm not going for the glory. It's actually, it's just about the work. And it's fun. I enjoy it.

[Jana Levin]

And you fully expect though, that there will be glory at the end of the day?

[Matt Kirshen]

I expect that there's a bit of me in the back of the mind that's like, yeah, it is gonna cause all of this. And I'm gonna.

[Jana Levin]

You're gonna be the name of a paint color.

[Matt Kirshen]

I will be able to break it up. But time, you just do it. You just drink that paint and you write down your results as best as.

[Jana Levin]

You'Re able to write.

[Ray Weiss]

So now we get to Kip. Because, see, Kip was a different kind of person. Kip was a theorist, okay? And he had spent a lot of his life thinking about what might be the sources of gravitational waves. And in fact, he started writing some very elegant stuff already in the 70s, early 70s, about if there were a way to measure gravitational waves, what would be interesting to detect. And he started inventing a lot of very interesting.

[Jana Levin]

So Kip really pushed the science case. And you know, he was so cool headed. He was just totally unflappable in the sense that even when other people were saying, we won't detect black Holes. We won't detect black holes until 2020. Some people told me as recently as August. Right. And Kip was like, nope, black hole's first. Black holes are going to be first. So he really pushed that scientific case.

[Ray Weiss]

Well, and he had good reason because, you see, he had developed a very. Probably one of the most prestigious groups in the country for the theoretical parts of gravitation. It's interesting. Kip and I, we didn't know. Well, Kip tells me he thinks he remembers, but I don't. We were both at Princeton together at the same time. I was a postdoc. He was a grad student. And by the way, Joe Weber was there also exactly the same time with John Wheeler.

[Jana Levin]

John Wheeler, the American granddaddy of American Relative.

[Ray Weiss]

So Kip was the reason. I think what's so important for Kip to be part of it is he gave it a certain cache. I mean, that. The fact is, he showed people that it was possible that you could have sources besides the one that anybody. Everybody knew about supernova, which was. Supernova, yeah.

[Jana Levin]

So when a star explodes, it can wobble space time, which we now think is probably the hardest thing to go for. Very hard source to do. So before we get to the discussion of the actual discovery, let's take some cosmic queries.

[Matt Kirshen]

All right, so Gabriel Thielen on who's a Patreon patron, says.

[Ray Weiss]

What kind of patron?

[Matt Kirshen]

Patreon, it's a website that lets people give their names.

[Jana Levin]

They are supporters of Fabulous show, financial.

[Matt Kirshen]

Supporter of the show. And Gabriel asks, theoretically, is there anything stopping gravitational waves from traveling faster than the speed of light? It is the same phenomenon, is it not? As a theoretically, a theoretical localized artificial space time distortion or war. Thank you very much.

[Jana Levin]

Can I try this one? And then Ray, you jump in. So just like there are light waves, electromagnetic waves, which is radiation, there is a particle complement to that, and that is a massless particle, and it travels at the speed of light. We think that that's exactly analogous to what's happening with gravitational waves. That there's a wave in the gravitational field and that there is a particle called the graviton, which is massless. In Einstein's theory, that might be wrong. But in Einstein's theory, it's massless. And in that case, like all massless things, it travels at the speed of light. No faster, no slower. But that could be wrong. It's very hard to test the speed of light by looking at gravitational waves. I'm sorry, the speed of the gravitational waves. It's very hard to test, isn't it?

[Ray Weiss]

Well, we try to make an attempt. You want to hear about that? I mean, if we ever get. I mean, there's a future and there's a current. I'll give you the future. Because it's easier to understand now that we are in the business, finally, of detecting things People will try to look for not just bursts of gravitational waves, but rather ones that are very steady radiators, like, you know, antenna on a transmitter blowing its waves out into space.

[Jana Levin]

Like a neutron star with a bump on.

[Ray Weiss]

It's like a paddle neutron star with a bump on it that's rotating. And so it gives a nice continuous wave.

[Jana Levin]

Like a monotone.

[Ray Weiss]

Yeah, exactly. Well, it's slowly decaying, but it's a monotone. You're absolutely right.

[Jana Levin]

Over our timescale.

[Ray Weiss]

And then what happens is a very interesting thing you can do, A very simple thing that even I can imagine. You can look at that source as we move around in our orbit in the solar system. And you will get added time. Each time source will be someplace in the orbit outside of our orbit. And we go around and it takes different lengths of time for the signal to get to us. And since we know our velocity, we can get the velocity of light because we increase the distance to the object we know how much we increased it by. So it's a very straightforward kinematic measure. On the other hand, we already have sort of a quasi measurement of the velocity of gravitational waves from a simple thing we saw. I have to explain, as Janice said, we have two of these detectors, One in Louisiana, another one in Washington state, and we saw the signal first in Louisiana, and 7 milliseconds later, we saw it in Hanford, Washington. Well, that already tells you it's moving pretty damn close to the velocity of light.

[Jana Levin]

Yeah, as it crosses the continent.

[Ray Weiss]

As it crosses the continent. That's a pretty good way of thinking.

[Jana Levin]

It's pretty great. I love that the 7 milliseconds are just clocked. It's fantastic.

[Matt Kirshen]

So Nathan Krueger on Facebook says, are there currently any plans to conduct the double slit experiment using gravity waves?

[Jana Levin]

That's an interesting question. Gravity is so weak, it's so hard to manipulate. Ray, what do you think?

[Ray Weiss]

I'll tell you what the real problem is. There are two problems. One of those, you can't make us. You would have to make an artificial source to do that. And when you start doing that, you'll find out that you just don't have the power. You can't accelerate enough mass and move it Fast enough so that you can even detect the waves. And Einstein said this in his very first paper on gravitational waves in 1916. He writes a lovely sentence at the end of the paper saying look points to all the calculations. He says no there's very unlikely. In fact he doesn't even say unlikely. It's impossible that these waves will have any physical consequence that we can measure because of that that he tried to look at things like stars that what he knew about or locomotives smashing into each other. I'm making that up because I don't know what he really thought about that piece of paper that says that's where he did his calculation.

[Jana Levin]

Yeah he didn't believe black holes were real.

[Ray Weiss]

Well the other thing is black holes not even going to be considered at that moment but just the calculation where he came so pessimistic about this. I'd like to have to see a piece of paper that has that he must have done it.

[Matt Kirshen]

So the fact that Einstein didn't think black holes are real and I do makes me smarter than Einstein.

[Ray Weiss]

Like what are we just a little later that's all.

[Jana Levin]

If you time traveled to before Einstein and believed in black holes that would make you pretty smart at that point. Do we have one last. We've got a minute for our last cosmos the question really quick.

[Ray Weiss]

I didn't answer the question but never mind.

[Jana Levin]

Sorry.

[Ray Weiss]

I know, I don't know you need to make an artificial source to make an interference but I just don't think we can do it unless.

[Matt Kirshen]

So Mary. Not Gonatelia. I don't think that's her real name. I'm almost guaranteeing that it's not. Says I asked this before as a silly question but I've been thinking about it. Maybe it's not so silly. If gravitational waves were represented by colors what would they be and why or how?

[Jana Levin]

Well yeah I mean the frequency of the sound can be translated directly to the frequency of light which is a specific color. So what colors would they be? They'd be. They'd be. Well these would be outside of the eye. Your eye would have to be like the size of a huge radio. I don't know very big too. Searching for the perfect place to grow your company.

[Ray Weiss]

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[Jana Levin]

Get started [e-mail] now @t mobile. Get four 5G phones on us and four lines for 25 a line per month when you switch with eligible trip trade ins all on America's largest 5G network. Minimum of 4 lines for 25 per line per month with auto pay discount using debit or bank account $5 more per line without auto pay plus taxes and fees and $10 device connection charge phones via 24 monthly bill credits for well qualified customers. Contact us before canceling entire accounts and continue bill credits or credit stop and balance on a required finance agreement due bill credits end if you pay off devices early ct mobile.com what makes a Carnival cruise fun? A picture perfect beach day at Cozumel or tropical adventure the Mayan ruins with snorkel excursion measure A delectable surf and turf at sea topped off with craft cocktails of alchemy bar. Now get some Z's. You never know what tomorrow will bring. Why?

[Ray Weiss]

Because no one does fun like Carnival.

[Jana Levin]

Carnival choose fun Ship's Red Street Bahamas Panama Now a lot of people are talking about the discovery. So and let's give people a sense of what actually happened. It was about what, 1.3 billion years ago two black holes collided. Now those black holes might have lived together a long time. What about the gravitational waves when they were far apart, when they first formed black holes when the stars died? What about those gravitational waves? You had an instrument up in 2000.

[Ray Weiss]

Yeah, well let's be honest about why we didn't see it in the year 2000. That's what you're complaining about, right?

[Jana Levin]

Well, I think you are.

[Ray Weiss]

We didn't have any this gravitational waves.

[Jana Levin]

Been coming across us since multi celled organisms were fossilizing on the Earth.

[Ray Weiss]

Let's start with what must have been the case with these. And I think this is probably going to hold even though there are other ideas now about this. But as you say, we saw the thing that happened about 1.2, 1.3 billion years ago and we saw it at its end point, at the very end when the two black holes were getting closer and closer. They were orbiting around each other and then all of a sudden they, they hit each other and they make a new black hole. That's what they do. They swallow each other as their event horizons come together. And you wound up with, let's say there were 230 solar mass stars to begin with and you wind up with a 57 solar mass black hole when they make a new one. So the first thing you have to explain is where did that three solar masses.

[Jana Levin]

They lost some mass.

[Ray Weiss]

Well, they went someplace. Well, they went into gravitational waves. But that's unbelievable when you Think about it, right?

[Jana Levin]

So it's completely. None of it comes out as lighted. A telescope at these two black holes colliding, I would see nothing.

[Ray Weiss]

See nothing. And that's one of the tragedies because you'd love to be able to see something so you could identify where it is. We don't have the faintest idea where it is in the sky, except for the fact that it hit Louisiana first.

[Jana Levin]

From the southern sky.

[Ray Weiss]

From the southern sky and went up. So we have sort of a banana in the sky where we think this thing comes from. But we have a sort of a thousand square degrees of ignorance is what we have. Right.

[Jana Levin]

So now there's a black hole out there and it's gone quiet. And we can't look at it either.

[Ray Weiss]

Nope, it's gone. You don't know where to tell people to go look for it. So that's sort of something we want to fix. But we'll get to how we fix that in a minute. Let's get back to what happened before we saw them. Okay. And there. It's a tricky one. It depends how they got made.

[Jana Levin]

Yeah. How did those black holes, if they got.

[Ray Weiss]

And we don't know how it got made? And that's going to be one of the more interesting scientific questions as we. When we go back on the air and begin to see a lot of these things, we can begin to contemplate. But there are two ideas that people had right away. One thing is a star collapses. That's called common envelope. And they come together and they make two black holes. By the way, Hans Bethe explained to me many years ago, just like Kip, that that's the first thing we would see. That was back in 1990. He's still alive. So that's one thing. That's one method that could be. Acquires a star. That's pretty heavy. 60 solar. 70, 80 solar mass star. Yeah, Big star. Big mammoth star. So where did that come from? Okay, that's. But then the other possibility, which is not quite as dramatic, is that we have things which are called globular clusters. What are those? Those are regions in our galaxy. And every galaxy has places where a lot of star formation forms simultaneously. And so here a bunch of stars all zipping around and there's a lot of probability that maybe three of them will get together, bang into each other. And it has to be orchestrated properly. Okay. And so they make a thing that's a black hole. Or maybe you have to make two black holes.

[Jana Levin]

Why can't it just be a Big star that died and made a black hole. Well, it's too heavy.

[Ray Weiss]

Well, it's. Yeah, be careful, Janet. It could be that. And people are thinking that. And some people even. Let me now go on.

[Jana Levin]

These are the McKay into a very technical conversation.

[Ray Weiss]

This gets into something really quite significant, let me say that's.

[Jana Levin]

What about the metallicity of this.

[Ray Weiss]

Ah, come on, let's get away from that.

[Matt Kirshen]

That was about to be my question.

[Ray Weiss]

I mean, your question. You were going to ask that, right.

[Matt Kirshen]

I was going to ask that.

[Ray Weiss]

Okay, well, the hell with the mentalicity for a moment.

[Jana Levin]

So we only see the final fraction of a second. How much of that collision do you actually detect did LIGO detect?

[Ray Weiss]

LIGO detected only about 0.2. Let's say a quarter of a second of this.

[Jana Levin]

A quarter of a second. So it was emitting the gravitational waves. It just didn't get loud enough into that.

[Ray Weiss]

Well, be careful. It's two reasons. Yes, you're right, but the real reason we didn't catch it is because our detector can't detect anything with very low frequencies. As I told you, it goes from the bottom of the piano to the top of the piano. So this is a rumble. Once they're very far apart, those stars, if they have been stars, if they started far apart, they might not have. You don't know that. Suppose, like every other thing, they started far apart. Then they would be going very slowly around each other hours, periods of hours.

[Jana Levin]

That would be low frequency.

[Ray Weiss]

We don't have any sensitivity. But something later in the history of man will have that sensitivity. It's called lisa. That's the space version of ligo.

[Jana Levin]

I love your optimism.

[Ray Weiss]

Well, it's going to happen. Maybe not mine, but in your lifetime.

[Matt Kirshen]

I'm building my own LIGO up home. Like, what kind of scale should I aim for?

[Jana Levin]

Do you know, that actually happened to me? I went to the LIGO lab. I am not actually an experimentalist in the collaboration, so I haven't signed the Memorandum of understanding, and there are certain things I'm not allowed to know. But I was looking at the schematic of the lab and I was like, why am I allowed to see this? And somebody said, what, are you going to go home and build one? Yeah, you got a couple. You watch me.

[Matt Kirshen]

And then everyone's going to be really embarrassed when you've done one for like.

[Ray Weiss]

Well, I'll tell you, if you come up with a clever idea that doesn't need something so big and people at one time thought maybe optical fibers, I won't go into it all, none of these ideas have worked out. But people all the time thinking about how could they make a small version of something like this that is as sensitive. But let me go back. So what you have is these big things that they're very. Let's suppose they got started separately and they come. They are still bound to each other and they eventually oscillate and they get closer and closer and they're losing energy to gravitational waves which we are not detecting because it's outside of our. Then we detect it just as it comes into our band. I see. So just as that's the most likely explanation, but there are others too, right?

[Jana Levin]

Now you were really hoping for the centenary for the first detection. So here you've been building this thing for 50 years, Ray. I can't tell you how many times somebody said to me, we better go ask Ray. You know, on site you're doing experiments, you're walking the beam tubes and you want it to be 2015. You wanted that so badly.

[Ray Weiss]

I know, 15 was good. 16 was the latest.

[Jana Levin]

Okay, so you were willing to take 16 and then if not that you would find an Einstein paper that was.

[Ray Weiss]

You know, it's a 2018 paper, but that was it.

[Jana Levin]

No, a lot of people told me 2018 don't expect a detection before 2018. But on September 14, 2015, this struck. It must have blown your mind. I mean, what is the experience of waking up that morning and checking the logs?

[Matt Kirshen]

Am I right? I'm thinking it was like it was the practice run that like, that wasn't meant to be the run that detected anything. Right.

[Ray Weiss]

You're absolutely unmarked. That's correct. Yeah. It's even worse than that. What happened is we didn't expect this. And when, as Jana points out, I happened to be on vacation, I had been at the site the days before that and I almost screwed it up. You know, that story I didn't do. But I do want to tell you the story because I was sent by my boss, Peter Fritchell, who is the young student that I had now is a senior member of this thing. He says, weiss, you got to go down there, fix the RF interference.

[Jana Levin]

Radio frequency.

[Ray Weiss]

Radio frequency interference and because it'll disturb the whole run. So I went down there and I saw what was really a big mess. I mean, fcc, you know, the Federal Communications Commission would have sent their truck there and shut us off because we put out so much rf. And then I found out the problem was. And I said to Peter, look, this is going to take A week to fix up. I don't. And they had a big conference. And the reason why they told me no was that they had committed themselves to making a run two days later, like it was. It was a run, and you had to. And he said, look, we have all these people coming from all over the country, all over the world, coming to the sites. We don't want to jeopardize this. And you're the rf if it's a problem, well, it can't kill us. And I said, no, it won't kill us for an impulsive source, but if you're looking for periodic sources, it might. And so we took that gamble. And Peter said, let's come home. Okay?

[Jana Levin]

Yeah.

[Ray Weiss]

And thank God.

[Jana Levin]

I want 24 hours later.

[Ray Weiss]

That's, what, about three days later? It was a Thursday. The thing happened on a.

[Jana Levin]

It happened on a Monday.

[Ray Weiss]

So it was four days later.

[Jana Levin]

Okay, so you check what's.

[Ray Weiss]

And so you asked what did I think?

[Jana Levin]

Yeah, you check the log. You wake up 8am in May.

[Ray Weiss]

Well, I'll tell you what happened. That was really cute. I went to log. We were on vacation. My wife and son were with me and her and her and his wife. And I was looking at the log, which I do every morning, and I see this thing, which was very cryptic. It says, we're canceling Fix It Day. Now, we have Fix It Day every Tuesday. We have running in the middle of a run. Even in an engineering one, when we find all these things wrong, we don't want to mess with the apparatus, but we do it at a certain time. So both sites are dead at the same time. And they said, no, we're canceling it. So I look at the other side, same damn thing. We're canceling Fix It Day. So I call up what's going on? And they say, well. And then. It didn't take long. I began to get. And very quickly, within about half an hour after that, I saw an absolutely magnificent curve, which was this signal, which now is on people's dresses. It's in everywhere. And it was this binary black hole, three solar masses. I look at it. It's. Holy mackerel. This has got to be a fake.

[Matt Kirshen]

Is it really mackerel that you said?

[Ray Weiss]

Yes. Well, maybe not. I'm trying to be careful.

[Jana Levin]

He's cleaning it up for air. If I know you, Ray, that's not what you said.

[Ray Weiss]

Gee whiz, no.

[Matt Kirshen]

None of those 1920s paper say, Mr. Mister. He got some scoops.

[Jana Levin]

It was really something. When? In February, all these months later the announcement was made and everybody just shared in this incredible excitement. That was really a moment in history.

[Ray Weiss]

It was. Well, we did a lot of work between the time we found it and then because we didn't believe it, let's be honest. I mean, Janna, that was such a big signal. We never expected such a big signal.

[Jana Levin]

Right. Amazing. Okay, we're going to go quickly to the lightning round. Are we ready?

[Matt Kirshen]

All right.

[Jana Levin]

Rapid fire.

[Matt Kirshen]

Kyle west on Instagram says, would it be possible for gravitational waves to alter matter as it passes through? For example, if matter was too close to the source, the gravitational waves could have become damaged or altered by the sheer energy or force of the waves propagating through the fabric of space time.

[Ray Weiss]

That's so easy to answer so fast. Gravitational waves are the most penetrating things that man has ever encountered. They go through everything, nothing's going to stop them.

[Jana Levin]

They go right through the earth.

[Matt Kirshen]

Alright, do gravitational waves cancel each other out like sound waves?

[Ray Weiss]

No.

[Jana Levin]

Beautiful.

[Ray Weiss]

Not to let me be parenthetic about it, they could, but it would take an enormous amount of precision to do that. You could have a compression while the other one is a rare fraction like water. It's not impossible, but my God, in the real world it's not going to happen.

[Matt Kirshen]

All right. If two black holes collided near us, would the gravitational waves be strong enough to disrupt our own magnetic field? What could happen because of that clash?

[Ray Weiss]

Well, if that collision happened in our solar system, we would be. We might not even be here. I'll tell you what happens. We would just.

[Jana Levin]

In our solar system.

[Ray Weiss]

Yeah, yeah. We would be stretched and compressed in such a way that things could easily come apart.

[Matt Kirshen]

That question, by the way. Schneider's on Facebook.

[Ray Weiss]

Okay.

[Matt Kirshen]

David Norio on Facebook says, why are we referring to gravity as a force since it's the result of the curvature of space time. And what about the other forces? Are they also the result of something we can't see yet?

[Ray Weiss]

Well, that's an interesting question, and I can't answer it because it may very well be we don't have the final theory, but maybe you should try.

[Jana Levin]

We're loose in this language. It's true that Einstein made us realize that in some sense gravity is not a force, that we're falling freely in a curved space time. We're not actually being touched and pulled upon. But there's another way to look at it that makes it look like a lot of the other forces. So electric fields permeate space and affect things. Gravitational fields permeate space and affect things. There's A way of making them sound more parallel. And there's always force carriers, gravitational waves, light waves, weak force carriers that gauge.

[Ray Weiss]

You can recast gravitation, as Steve Weinberg did, for example, as a field theory if you want. You don't have to use Einstein's beautiful theory.

[Jana Levin]

Well, what people say is if Einstein hadn't discovered curved spacetime theory, we'd be talking about it in this much more particle physics Y sort of a way.

[Matt Kirshen]

All right. The Scarlet Speedster on Twitter says, how do gravitational waves affect time? Perception of time? What would need to occur to have significant changes?

[Ray Weiss]

Well, I don't know if I can answer that. The metric that I use does not have the clocks perturbed.

[Jana Levin]

This is chicken.

[Ray Weiss]

By the gravitational waves.

[Jana Levin]

Yeah. So it's like what I call left isn't what you call left. It's a mixture of your left and right. We tend to orient our space time so that it's only the space that changes, not the time. But you could orient your space time differently where you would measure it being in the time direction. It's not easy stuff.

[Matt Kirshen]

Alright. Tony Hale on Facebook says, do gravitational waves reflect light? And if so, could you dial in an image, like flipping a page in a book? If we can't see our galaxy in the past, but the light reflected from our galaxy is traveling faster than we are, would that mean we could see an image bounce back at us?

[Ray Weiss]

I don't think that'll happen. But let me tell you something. It's a very nice way of thinking about gravitational waves affecting the propagation of light. You don't have to have mirrors. In other words, they interact to make sidebands on the light. That's a complicated way of saying it, but. For example, some of the other ways of looking at gravitational waves do not use mirrors. Like the pulsar timing does not use mirrors. So consequently there's an interaction between gravitational waves and the propagation of light.

[Jana Levin]

Yep. That is some hard stuff. I'm not even going to try to clear it up because we're at the end of our show. Thank you so much for the excellent questions. It's been a great show today. Ray, always an honor. Thank you for having me to talk to you. Matt, so great to have you on. Thanks so much for being here with me. This has been StarTalk All Stars. Thanks for listening. See you in the multiverse. Sponsored by Novo Nordic Risk. Hi, I'm standing in quicksand. You can't see it, but it could be true. Having MASH can often be the same way. MASH or metabolic dysfunction associated steatohepatitis is a potentially life threatening liver disease you could have without knowing, especially if you have conditions like obesity, type 2 diabetes, or high triglycerides. You don't know if I'm in quicksand and you won't know if you're at risk for MASH without Talking to your doctor doctor. Learn more at speakliver.com Imagine what's possible when learning doesn't get in the way of life at Capella University. Our game changing flexpath learning format lets you set your own deadline so you can learn at a time and pace that works for you. It's an education you can tailor to your schedule. That means you don't have to put your life on hold to pursue your professional goals. Instead, enjoy learning your way and earn your degree without missing a business feet. A different future is closer than you think with Capella University. Learn more at Capella Eduardo.