Hello everyone and welcome to the Mindscape Podcast. I'm your host, Sean Carroll, and

I bring you bad news, namely that the world is going to end. Not the world is in the

earth that we live on, but the universe as a whole is going to come to an end. Someday,

we don't exactly know when. And what I mean by an end, it might not be something as dramatic

as literally the universe ceases to exist, but it might either change so dramatically

that life itself would be impossible, or it could just fade away. The universe could end

with a bang or with a whimper. So today, I talked to one of the experts in this slightly

depressing area. Katie Mac is a theoretical cosmologist at North Carolina State University.

Also a very popular science communicator, her Twitter feed is one of the top ones that fellow

physicists follow. And we talk about the different scenarios that sketch out what might happen

to the future of the universe. It's not something that we know about, for sure, right? Making

predictions is hard, especially about the future. But we know enough about the laws of physics

to say what the range of possibilities seems to be. Either this sort of gently fading out,

everything moves apart from everything else, and we just get colder and slower until the

interesting, lively aspects of the universe just fade into nothingness, or it could be something

very dramatic. My favorite scenario that we talked about in this episode is the bubble of quantum

death. If you're not familiar with what that is, it'll be explained to you in grisly detail.

So this is both an educational episode, and that we really do get into some real physics and

cosmology, but also thought-provoking that science has progressed to the point where we can

actually say something about what the end of the universe might be like. Remember, if you want

more info on Minescape, you can go to the podcast homepage at preposterousuniverse.com slash

podcast, where you can also sign up to support Minescape on Patreon. If you want to get

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