Sean Carroll

You could be asking for

these AMA questions.

Once in your life, you could get a priority question that I would do my best to answer.

We also get little reflection audios after every interview podcast.

I don't do it after a solo or an AMA because I've just been talking for a long time anyway.

But there's a lot of benefits spiritually as well as intellectually to being a Patreon supporter.

So think about that if you're not already.

Thanks to everyone who already is.

And with that, let's go.

I'm going to start by grouping three questions together.

When I ask the Patreon supporters for the AMA questions, I put up a post saying, you know, give me your questions.

And at the beginning of the opening of this month's version, I mentioned that I was working on a paper

with a new theory of the universe and so um hopefully uh it's out by now or at least hopefully by the time you're listening to this it's on the archive and if it is then i will put a link to it in the show notes um but the questions all have to do with that since i made a provocative little statement sandro stuckey says please tell us about that paper you're working on the one that suggests a new scenario for the possible history of you know the entire universe the

Ben Lloyd says, is cosmic expansion existing enough to invalidate the Poincaré recurrence being applied to our universe?

Or can recurrence still happen in eternally inflating desiderate cosmologies because of finite desiderate entropy?

I'm asking because I recently saw a physicist argue that Poincare recurrence likely does not apply to our universe, since the theorem assumes something like a bounded system with finite accessible phase space, conserved dynamics, and our universe has expanding spacetime rather than particles confined in a fixed finite volume.

And then Sean Sullivan says, with the recent DESI and DES data suggesting a preference for dynamical dark energy that weakens over time, the possibility of a big crunch could be back.

Given that our universe is highly anisotropic, how would you imagine the big crunch to physically occur?

Would the collapse happen synchronously or would high density areas hit localized singularities where voids are still collapsing?

What would the mechanics of those localized crunches look like to an observer?