Re: poly: eschatology

"Nick Bostrom" <bostrom@ndirect.co.uk> writes:

> Hal Finney <hal@rain.org> wrote:
> > Unless there are some ad hoc topology wraparounds, the zero and negative
> > curvature universes are infinite in spatial extent, with an infinite
> > number of stars, unlike the closed universe.
>
> How should we intuitively picture such an open universe if we in our
> imagination travels backwards in time?

Imagine a plane which expands, so that the point (x,y) (like a star at
rest relative to its surroundings) at time 1 becomes (tx,ty) at time
t. As you approach t->0, the stars move closer and closer together;
for any remote star there will be a time when it is within radius 1 of
the origo. At t=0 the whole plane "impodes" to a point.

-- 
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Anders Sandberg                                      Towards Ascension!
asa@nada.kth.se                            http://www.nada.kth.se/~asa/
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