"Bottom of the barrel"? Really?
My god, man! He holds Newton's Mathematics chair at Cambridge- have you no respect?

And the key parts are : "my god man !"

It's a head twister to be sure. Well- before some event there was nothing, not even time, and then there was. poof.

As proof I offer... nothing.

Now, for me, I fall into the more foolish category of "so what?" Or what do we do now? Yes it would be intellectually satisfying to know how everything started- and how it will end - but God doesn't consult me in any way I can understand so I don't know, I'm not going to know, and yet I can still eat and get laid.

Well, anyway I can eat whenever I want- and I love the fluffy carbs.

So- unless it's going to help the Cubs break the 100yr drought- I'm not sure I care. Other than in a potentially intellectually satisfying way.

Just to clarify -- that "bottom of the barrel" refers to how (emotionally) satisfying the explanation is. I would hardly put myself in the position of attempting to judge the elegance of Hawking's reasoning nor the eloquence of his explanation.

I'm unqualified to do either, for the reasons you state.

Corichi and Singh talk in terms of our universe being a lot like the one that came before it, but nothing I read above rules out the possibility that this universe is a dead ringer for its ancestor.

Well, nothing except the sort of basic physics you learn while flipping coins as a six year old. Even if the physical laws are identical, there are behaviors right down to the quantum level that are not only unpredictable, but as far as we know completely random. And over time, little differences add up to big differences. The last iteration, and the next, would have protons, neutrons, oxygen, stars, galaxies ... but they are very unlikely to have people, sitting on Earth, reading and writing a Speculist blog.

As I read the article, it seems that there are far fewer differences -- or I should say the differences that occur are at a far smaller level -- when comparing these two universes than when comparing successive coin flips. It's not just the same physical laws, it is precisely the same amount of matter, etc. The initial differences between the two -- if any -- can be identified only at the Planck scale.

The last iteration, and the next, would have protons, neutrons, oxygen, stars, galaxies ... but they are very unlikely to have people, sitting on Earth, reading and writing a Speculist blog.

Woody Allen's take on Eternal Recurrence was that he hopes it's not true -- he wouldn't want to have to sit through the Ice Capades again. People in the next universe should be so lucky as to have The Speculist to read!

Interestingly, you can have Eternal Recurrence even without exact duplicates repeating back-to-back. Assuming a finite (though very large) number of particles in the universe -- and an endless succession of twin universes -- we would inevitably cycle through the exact same configurations over and over again. There might be trillions and trillions of iterations between each instance of the Speculist (or Ice Capades) universe, but it would keep coming up, as sure as the number 19 on a roulette wheel.

Ah, but you said the next universe, and the immediately previous one. Even if there are differences only at the planck scale, you'd have to convince me the system isn't sensitively dependent --- which would mean that Planck-scale differences would still lead to bigger ones.

I think Julian Barbour suggests the universe is a (has a) configuration space of around 10^500 configurations, so yeah, you've expect eventually to exhaust them, and in fact to exhaust them infinitely often.

Charlie --

I wonder when in a universe's lifespan this quantum bounce occurs. We were talking on the podcast last week about the heat death of the universe, which will occur somewhere after about 10^150 years. Let's say the bounce occurs much earlier than than that, on average, but still in a much older universe than we currently occupy, say one that is 10^100 years old. So you have to wait 10^100 years for each of -- if not 10^500 universes, then at least some significant subset of that number -- to go by before coming back to "our" universe.

This kind of talk makes me dizzy.

BTW, I'm a big Julian Barbour fan; I once won a prize for a speech I gave about one of his books.