PeterDonis's latest activity

I'll see if I can find a reference to the theorem I mentioned.

I'm not sure it's just a matter of "postulating". The Reissner-Nordstrom metric, according to the theorem I referred to, is the unique...

Yes, and what Wald wrote is consistent with what you wrote in #2. Wald agrees that adding a term to the SET has gravitational effects...

It depends on how the sheet is getting close to the BH. If it's freely falling, that's one thing. If it's being supported against the...

I'm not sure what you're asking. What kind of scenario do you have in mind where an object might or might not break apart?

I'm not sure you are. The point of the passage from Wald that was quoted is not that there is a difference in the measurable effects of...

That's not just a "restriction" on ##\mathbf{V}~##. It means ##\mathbf{V}~## has to vanish. The SET vanishing means no stress-energy can...

There is an analogue of Birkhoff's Theorem that shows that the only spherically symmetric electrovacuum solution (i.e., the only...

Yes, the way I phrased it was odd. I should have said that the eternal inflation models that are ruled out meet condition (b) (because...

It rules out models that (a) are expanding everywhere, and (b) do not have a past spacetime boundary. As I noted earlier, de Sitter...

Correction to what? In the sense that, while every worldline has a finite extent into the past, there is no upper bound to those finite...

No. There are no such models; "extend infinitely into the past" and "contain singularities" are contradictory. They can't both be true...

Ah, thanks for the link. Note that in the further discussion in that thread, a model due to Linde was mentioned which he still describes...

Yes, that's true. But one of the assumptions is that there has to be an everywhere expanding congruence in the spacetime. de Sitter...

The terminology in the literature is unfortunately not consistent on this point. To me, it makes the most sense to use the term "Big...