Warp wrote:
>   1) Spacetime inside an event horizon is pretty weird, and the spacetime
> we currently reside in isn't (relatively speaking, at least).

It's only weird if the event horizon is small. A galaxy-sized black hole, 
you could fall into and not notice.  And it's not like you can get outside 
the event horizon of the universe.

>   2) All spacetime geodesics inside an even horizon point towards the
> singularity. (Ok, in a rotating black hole it's more complicated than
> that, but in principle I suppose it's the same.) We are not moving towards
> a singularity; we are expanding, hence moving *away* from any possible
> "central point" of the Universe. That kind of contradicts the idea.

Unless there'a big crunch? :-)

>   Of course I am no physicist, and I have zero knowledge of the GR
> equations, so I could be completely off track with this. My point is,
> however, that I just don't understand how that hypothesis could be even
> worthy of consideration.

I think it was more popular before people found dark energy and thought we 
were heading for a "big crunch" or something?

>> But I suspect it's the giant FTL "inflation" or some other wonkiness of 
>> pre-first-microsecond space-time that means the "singularity" wasn't all 
>> that singular.
> 
>   I have read somewhere that it's considered that even if the entire
> Universe was concentrated in a singularity at the beginning, it's hard
> to say anything about its nature because anything prior to the first
> unit of planck time did not obey any current laws of nature (in other
> words, laws of nature break up when we go back in time more than one
> planck time unit after it all started).

Basically, yes. Plank time and plank length are the quantums of quantum 
mechanics, so there *isn't* anything smaller than that. It's like asking for 
half a bit of information.

-- 
Darren New, San Diego CA, USA (PST)
   Serving Suggestion:
     "Don't serve this any more. It's awful."

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