Neil deGrasse Tyson defends engaging with opposing viewpoints while criticizing sensationalized science journalism, noting astrophysicists rarely address existential threats like asteroids or climate change. He highlights unresolved cosmic mysteries—dark matter (85% of the universe’s gravity), dark energy, and pre-Big Bang conditions—as frontiers demanding a multiverse framework, dismissing "no time before the Big Bang" as philosophically inadequate. Speculating dark matter might be matter from adjacent universes, he warns traversal could dissolve matter due to conflicting physical laws, despite the multiverse’s current untestability. Tyson also distinguishes between debunking false biblical claims and respecting religion’s spiritual role, rejecting "science of the gaps" critiques while acknowledging the multiverse theory’s quantum physics roots. [Automatically generated summary]
Neil deGrasse Tyson, thank you so much for coming on.
I appreciate it.
Thanks for having me back.
You know, I got to tell you before we start, I have a million things I want to talk to you about, so I won't take too much time.
But I just want to tell you how much I respect you.
There'll be a thousand things per second.
Exactly.
Exactly.
If you do the math.
We won't even worry about the speed of light or anything.
But I want to tell you how much I respect you for coming on this show and on Ben Shapiro's show.
I know there are people who demonize you for showing up on shows that where they have opinions that they disagree with and maybe you disagree with.
And I appreciate you're bringing science to my audience and other people's audience as well.
So I really think that does.
I'm delighted to.
Without conversation, there is no civilization.
Absolutely.
That's how I see it.
So much of news reporting about science is politicized and geared toward disaster, terrible things that might happen that are happening.
What are you thrilled about right now in the field of astrophysics?
What's happening that we don't hear about that's really a breakthrough and exciting?
Yeah, just a comment about sort of disaster reporting.
While there are some scientists who can thrive on that, it's mostly journalists who are, because you can get a bigger headline if you're going to say that the world is going to enter, that the asteroid is going to hit.
And that's not uniquely applied to science.
That's applied to practically anything that goes on in journalism today, particularly when an article now appears online and then it becomes clickbait for some nearby ad that gets posted there.
So there's been a shift in the honesty of what actual threats are or have been in reporting, which is I'm concerned about that because some people only ever read headlines.
The only disasters that an astrophysicist would ever present to you is the threat of an asteroid, for example, or an attempt to further communicate what's going on on Earth as a planet climactically, because we also study other planets climactically, which gives us a cosmic perspective on climate change and other things that have long-term effects.
Personally, for me, in the universe, I'm still eagerly looking for a solution to what dark matter is in the universe.
It's 85% of the gravity of the universe has no known origin, but we measure its effect on everything else, and it's just a mystery.
And then there's this thing we call dark energy, which is a mysterious pressure in the vacuum of space that's making the universe accelerate in its expansion against the wishes of the gravity of all the galaxies.
And so both of those together, it's a profound state of ignorance that actually is quite exciting because if we solve that, it could solve a host of other things that have been perplexing us for so long.
Dark Matter Mystery00:03:40
And two last quick points to make.
Another frontier, but this from biology, is how do we go from organic molecules to self-replicating life?
That's a frontier in biology.
And last in my field, it's like what was around before the Big Bang, right?
We have top people assigned to these tasks, but they remain fascinating frontiers that we're all sort of scratching our head about.
That really is interesting.
I always hear people, when people ask that question about the Big Bang, I always hear scientists say that there was no before because there was no time.
That's a very unsatisfying answer.
Yeah, it's completely satisfying to me as well.
It's an answer, but to make that your only answer, I think is it is true we define the beginning of time as the Big Bang.
And there's no way to think about measuring time outside of this universe.
So to say that there's a before the clock even existed might be a philosophical issue.
It's like saying what is north of the North Pole.
Well, the North Pole is by definition the North spot where Santa Claus is, right?
So you can't get more north than that.
So yeah, so interesting you remembered that and remembered being frustrated by it.
You were completely, legitimately frustrated by that kind of an answer.
What it calls for is if the multiverse is a thing, we would need some way of reckoning time that transcends timekeeping within our own expanding bubble.
So you'd have sort of a meta time, for example, in the higher dimensions of the multiverse.
I want to get back to the multiverse in a second, but before that, you open letters from an astrophysicist with a tribute to NASA.
And one of the things I keep hearing is sort of filtering into the conversation these days is people saying that really manned space, interplanetary space travel with an eye toward colonizing other planets is a myth.
It's a complete pipe dream.
It'll never happen.
Do you agree with that?
No.
Well, there are very good arguments for and against it.
And there's no reason to dogmatically settle on one or the other.
The reasons for it are it's kind of it would be good to be a multi-planet species.
And there's nothing wrong with that.
Okay.
That ensures our survival.
We became multi-continent, and the voyages across the oceans took as long or longer than some of the trips we're taking in space.
So, of course, the difference is when Columbus landed in the new world, he was greeted by other human beings.
When he gets off the ship, he can breathe the air in the new world, right?
And if a ship needs repair, the trees are also made out of wood in the new world.
Whereas if you land on Mars, you can't breathe the air.
There are no replacement factories for your broken circuit boards.
And there's no farmland.
There's no natives to feed you and help you not die.
So the challenge is yet to be something to be realistically resolved.
One of my favorite words of the past few decades is terraforming.
One way to do it is you terraform Mars.
Elon Musk is big into that.
The idea that you could seed the atmosphere or the soils with microbes so that they then generate oxygen and pump oxygen into the air, creating an ozone layer.
And you just sort of turn Earth, turn Mars into Earth.
And then you just move there.
Why Scientists Avoid Simple Explanations00:06:27
Then it's not a matter of do you need your food.
You're basically homesteading at that point.
So they're interesting and strong arguments in both directions.
And I haven't landed on one or the other yet.
As for interstellar travel, no, that's not happening.
It's never going to happen.
I can send you on a ship, you'll get there in 100,000 years.
Right.
And that's wholly incommensurate with your life expectancy.
And you don't think any of the science fiction ideas about wormholes or anything like that is happening?
So if there are wormholes, we don't know how to keep them propped open.
They're very unstable.
Our equations tell us that they are unstable.
But if we're going to travel across the galaxy, we need wormholes and or warp drives, which is just, you know, is de rigueur in sci-fi storytelling.
But yeah, so I can't wait for that day.
That'd just be fun.
But you're not holding your body.
But if without that, we're not going anywhere.
We're not leaving the solar system.
All right.
Now, you and I have very different religious outlooks.
I'm a deeply religious Christian, and obviously you have some unkind words for the Bible.
Laughed out loud at your, the guy who wrote you saying he heard the voice of his dead father, and you had all these questions.
You wanted him to ask his dead father.
Oh right, if you're going to have a conversation, if this is someone who wrote in, who had a two-way conversation with her dead father on a slab in the funeral home and all I, I couldn't help but just say okay, the next time this happens, ask these questions, not the ones that you ask.
All right say, where are you?
Are you wearing clothes?
Do you eat?
Who makes the food?
You know?
Ask, ask questions that can give serious information from the other side.
Um, otherwise it's just not as useful.
And and if and if she's really communicating with the other side, that would be extraordinary.
Why not get evidence that?
Could that?
Could um establish that definitively?
It's so.
It's such a science.
I don't think I make fun of the bible.
I, I just reference it.
If it makes something, it says something that's that's objectively false, i'll say so um, but i'm not.
I, I don't this.
Tons of religious people are not using this, the bible the the, the Judeo-christian Bible, as a textbook to understand the physical universe.
What tons are saying?
The Bible is a place where I get spiritual emotional, philosophical wisdom, but i'm not comparing it, chapter and verse, to to to nature, right?
So it's not.
It's not really as big a problem as people want to say.
It is between science and religion, you know, I I agree with this.
But you, you make some really good points about uh, religious people sometimes replacing science with superstition.
Perfectly fair.
But it also seems to me that sometimes scientists go out of their way to avoid the simplest explanation, which is why I wanted to ask you about the multiverse.
The multiverse, the multiverse seems to me an unprovable theory that is supposed to answer the question of how we wound up with this completely unbelievable universe that we can understand, which seems uh, against all odds, isn't it?
You know they used to accuse religious people of having a god of the gaps, of filling in places where there is no scientific information with god.
But isn't that science of the gaps?
Isn't that filling in?
Like answering a question with something, a completely unprovable theory, where you could just as easily say it had to do with a creative?
That's an excellent question.
So a couple of things.
First, it's never it's, it's it's almost never good for a scientist to put forth an idea that cannot be tested.
That's just not useful.
It may be true, it may not be true, but if we can't test it, we we'll move on to some other problems that are testable right, it's just a matter of the practicality of invested time.
So I just want to say that, with regard to the multiverse, we didn't just pull that out of nowhere.
All right.
What happens is we learned about quantum physics that was discovered in the 1920s.
Think of that as the physics of very small things, so atoms molecules, atoms and nuclei.
Okay, there's a whole world down there that is behaving, behaving in ways wholly, entirely unfamiliar to us, outside of our senses.
Particles pop in and out of existence and it's a crazy world.
But it's true, and in fact, the entire IT revolution is based on exploiting our understanding of quantum physics.
General theory of relativity put forth by Einstein is the theory of the large, and that explains the big bang, the expansion of the universe, all of that.
And it turns out those two understandings of the universe do not play well together in the sandbox.
They work in their own regimes, but you put them together as one coherent whole, they do not agree with one another.
This is where the string theorists came in to try to unify those two branches of physics.
But now, here's where it gets interesting.
At the Big Bang, the large was small.
So what happens when the entire universe was the size of an atom?
And so what the quantum physics people were doing was saying, let us proceed with applying quantum physics to the entire universe when the entire universe was as small as an atom.
What do you get?
You get multiverses.
And each multiverse has a slightly different laws of physics operating in it than another multiverse.
So we were forced to that by already successful and already tested theories of the universe.
And that's why it's on the table for discussion.
And maybe there is a way to test it that we have not thought of yet.
For example, gravity has a way of leaking out of one universe and can penetrate the boundaries of an adjacent universe.
Could it be that dark matter in our universe is regular matter in an adjacent universe whose forces of gravity we feel across the boundary membranes between their universe and ours?
Could it be?
I mean, I'm just saying it's to propose something and in that moment not know how to test it should not mean to discard it entirely.
Wormholes and Dangerous Universes00:00:49
You put it on the shelf and maybe something will come along one day that will allow it to be tested.
Maybe we'll master wormholes and you wormhole from one universe to another.
That would be dangerous though, because if the Laws of Fleets are slightly different, you could dissolve into a pile of goo because the charge on the electron no longer holds your molecules together, for example.
So that would just be really dangerous, but that's the kind of thing you'd want to be thinking about.
So no, we didn't just invent it just to make us happy.
No, it followed out of already successful tested ideas.
Well, that's the first time I've ever heard explained where it made any sense whatsoever.
So I appreciate it.
Neil deGrasse Tyson.
The book is Letters from an Astrophysicist.
Thanks so much for coming on.
I really enjoyed talking to you, and I hope you come back.