Professor Geraint Lewis

Cars around me crashing and there was one car careening towards us.

And when it stopped just next to us, I turned to my wife and I just said to her, that felt like half an hour.

And it was a fraction of a second, I'm sure.

But it felt like forever seeing this car come in towards us in slow motion.

that's an excellent question um it's actually kind of hard to get stuff out of a galaxy so we we actually do see some stars that we know are escaping they're traveling at a few thousand kilometers per second and we think that they've come from the galactic center where they've interacted with the supermassive black hole there so if you have just a rogue planet on its own um it's very hard for it to escape a galaxy unless you do something dramatic

And what's going to happen in about 4 billion years is that Andromeda and the Milky Way are going to collide.

And in that collision, the Milky Way is going to be seriously upset and essentially torn apart.

And in that scenario, it's estimated that 10% of all the stars and planets will be ejected into intergalactic space.

And so these events have happened over the history of the universe.

And so there must be rogue planets in between the galaxies.

If they're with their host star, they probably are okay.

But if they are away from their host star, they're probably frozen by now.

No, no, no.

So it's the entire action of the galaxies interacting.

Big chunks of the galaxy will be ripped off and thrown out.

Oh, chunks.

Yes.

Well, the honest answer is we don't know.

When I work with relativity, I see that time travel is not ruled out by the equations, but we just do not know how we could make it work.

So it might be a smart kid gets up tomorrow and has the right idea and we've got time travel, or it may never happen.