Neil and Chuck introduce the show and their guest Brian Green. They discuss Brian's background and accomplishments.

Introduction

They discuss Brian's new book "Until the End of Time" and the questions they will be answering from it.

Brian Green's New Book

A question is asked about what Brian thinks is the actual meaning of the universe. He discusses how there is no ultimate meaning and we impose our own meanings.

The Meaning of the Universe

They discuss questions about where the universe ends and if we can ever travel beyond what we can observe. Brian explains the cosmological horizon.

The Edge of the Universe

Neil asks a hypothetical question about what time would be like beyond the cosmological horizon. Brian explains it could be the same or different.

Time and the Horizons

They discuss a question about consciousness and if the human brain can understand it. Brian believes it is a physical process from particles in the brain.

Consciousness and the Future of Thought

They discuss what religions may think if contact was made with an intelligent alien civilization, especially if they claimed to have created humans.

Religions and Alien Contact

Neil asks if there could be missing laws of physics we haven't discovered yet. Brian believes there likely are at higher unexplored energy scales.

The Future of Physics

Brian shares his hopes that a deeper level of consciousness may one day enable a greater appreciation of the cosmos. They thank Brian and end the episode.

Final Thoughts

- Neil deGrasse Tyson and Chuck Nice host a Cosmic Queries edition of StarTalk with guest Brian Green.
- They discuss Green's book "Until the End of Time" and its subtitle "Mind, Matter, and Our Search for Meaning in an Evolving Universe".
- The hosts and guest discuss the possibility of interstellar travel within the lifetime of the human species.
- Green explains that the laws of physics limit spacecraft speed to be less than the speed of light, making long-distance space travel challenging.
- However, if a spacecraft were to travel near the speed of light, time dilation would occur, allowing the travelers to go further in their lifetime than those on Earth would perceive.
- The hosts and guest also discuss the idea of sending a colony of people on a ship to seed another part of the galaxy, but note the ethical implications of giving birth to children who will never know Earth.

The video features a conversation between Neil DeGrasse Tyson and Brian Green. They discuss the possibility of interstellar and intergalactic travel and how it could potentially lead to the speciation of humans. They also explore the concept of time and whether it is made of something. Green explains that recent developments in fields like string theory suggest that the fabric of space and time may be stitched together by quantum entanglement. They also discuss the idea that dark energy could cause the fabric of space to tear apart, but Green assures that it would repair itself. The conversation touches on the review process for science books and the decline in science book reviews by newspapers.

- The video features a conversation between Dr. Brian Greene and Dr. Neil deGrasse Tyson.
- They discuss the possibility of fully understanding the universe and manipulating unknown forces.
- They acknowledge that there may be limitations to human understanding, but there is no evidence of a limit to what can be figured out.
- They mention the challenges of string theory and the need for further experimentation to make progress.
- They discuss the potential for new laws of physics to be discovered at higher energy scales.
- They emphasize the importance of being clever and finding creative ways to explore the unknown.
- They touch on the topic of finding meaning in the universe, acknowledging the role of religion in understanding one's place in the world. 
- They address a question about the ending of the universe, discussing the possibility of both place and time endings.

- The video discusses the concept of the end of space and the possibilities surrounding it.
- It suggests that space could either go on infinitely far or be curved, allowing for a finite extent.
- The idea of traveling infinitely far in a finite space is explored.
- The observable universe is mentioned, with evidence of the Big Bang being seen at its edge.
- The horizon of the universe is discussed and the idea that it could be the edge of space.
- The conversation touches on the possibility of time being the same outside the universe and the idea of a cosmological horizon having a temperature.
- The concept of a cogitating being being unable to release heat in the far future is mentioned.

- The increase of entropy is one of the arrows of time, but reversing entropy wouldn't reverse time, just physical processes.
- If we were able to reduce entropy in the universe, it would have significant consequences for our understanding of nature and the future.
- The response from world religions to contact with another civilization would likely be minimal, as they already have their own perspectives on the origins and purpose of life.
- There is a religion called Ray-aliens that believes intelligent aliens created us, so the existence of other intelligent life wouldn't be a major issue for them.
- Consciousness is a physical process and nothing more, fully determined by particles and physical laws.
- The understanding of consciousness and the cosmos will continue to evolve as we learn more about reality.

- Neil deGrasse Tyson and Chuck Nice host a Cosmic Queries edition of StarTalk with guest Brian Green, discussing Green's book "Until the End of Time" and the possibility of interstellar travel within the lifetime of the human species.
- Green explains that the laws of physics limit spacecraft speed to be less than the speed of light, but time dilation could allow travelers to go further in their lifetime than those on Earth perceive.
- The ethical implications of sending a colony of people to seed another part of the galaxy are discussed.
- The conversation also explores the concept of time, the fabric of space and time being stitched together by quantum entanglement, and the potential for new laws of physics to be discovered at higher energy scales.
- The video touches on finding meaning in the universe, the potential ending of the universe, the concept of the end of space, and the idea of traveling infinitely far in a finite space.
- The conversation also mentions the observable universe, the horizon of the universe, the possibility of time being the same outside the universe, and the increase of entropy as one of the arrows of time.
- The response from world religions to contact with another civilization and the understanding of consciousness and the cosmos are also discussed.

Neil deGrasse Tyson, comic co-host Chuck Nice, and theoretical physicist and author Brian Greene answer questions from our fans about string theory, the fabric of spacetime, interstellar travel, free will, and the meaning of life.

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

Neil deGrasse Tyson here, your personal astrophysicist.

And as is not always, but most of the time, Chuck Nice.

We just fist bumped in front of our guests.

Here we go, now we'll do a three-way fist bump.

We're doing Cosmic Queries Until the End of Time.

I didn't just pull that out of an orifice.

Mind, Matter, and Our Search for Meaning in an Evolving Universe.

That is, But doesn't the universe automatically elicit questions of what is my purpose, my meaning, why?

That's why we have him here to talk about this for the show.

So we solicited questions About this book.

I don't know, people read your book already?

And there is several of the questions of people who have already, they say, in your book.

Your book, until the end of time, brings me to the conclusion.

All right, so this is the Venn diagram that overlaps his fan base with our viewers.

Because we solicited it from our viewers.

Just to remind everybody how this works, it's Cosmic Queries, and these are solicited from our fan base.

I have not seen them, certainly our guest hasn't.

And Brian Green and I have very strong scientific overlap, but we're gonna get his view on this, and I'll just sit back and listen, and if he's full of shit,

knows almost all the astrophysics I know.

And I only know some of the physics he knows.

I mean, I'm going to say yes to that Because he's an astrophysicist and a physicist.

Math is a language of the universe in which he is fluent.

I'm delighted to have an old-time friend and colleague.

Let's do this and as usual, we always start with a Patreon question.

Brian Green is professor of physics at Columbia University.

And also joint appointed in the Department of Mathematics.

And He and his spouse co-founded the World Science Festival here in New York City every year, where science and art and music come together to celebrate science.

just some person who's sitting between us right now.

I didn't want to undo the fact that he's a person sitting between us.

Okay, and his first book that anyone knows about was a mega bestseller, which was?

And he's 1 of our leading string theorists, and this was a way to share not only the frontier of his research with all the rest of us, give us a sense of hope that maybe 1 day we'll understand everything.

Then he got so famous, he found another publisher.

And then he published another book after that, and it didn't do as well as the first book.

You're just giving your publisher some cred right now.

As I said, we always start with a Patreon patron because they give us money.

I often wonder how far we will journey through space within our lifetime will we be able to achieve interstellar travel or will the human race go extinct before we have the opportunity and technology now he started off with our lifetime but I think he means the lifetime of the species of human beings, because our lifetime, the answer is no, and I am not an astrophysicist at all.

No, within the lifetime of the human species.

First of all, what is the lifetime of a human species?

look at the life expectancy of mammal species, 1 in 3000000 years, somewhere around there.

I mean, we have this thing on top of our head that able to figure things out.

So either that is going to be our own destruction because we can build things that can kill ourselves or we'll be able to figure out a way of living beyond the traditional lifetime of many species.

There's what's possible in the laws of physics and there's what's within reach with our engineering.

Well, the laws of physics constrain any speed of any spacecraft traveling through space to be less than the speed of light.

So if you're not going to play games with imagining that we can actually warp the fabric of space and

But taking the speed of a craft to be less than the speed of light, then I mean achieving great space travel is challenging, right?

Now, the weird thing is, because time slows down when you have a spacecraft or a clock of any sort that's in motion, you could have a spacecraft going out near the speed of light, and we on Earth would watch its clock, and its clock would be ticking off time so slowly that to the person on the ship, they would be able to go much further than we would think they would be able to if we didn't take that into account.

So, you know, we could send, you know, some intrepid voyager out into space and they could go-

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Cosmic Queries: Until the End of Time, with Brian Greene (Re-Release)