From: Anders Sandberg (asa@nada.kth.se)
Date: Sat Aug 17 2002 - 05:58:48 MDT
On Fri, Aug 16, 2002 at 08:21:28PM -0700, Cory Przybyla wrote:
> --- Rafal Smigrodzki <rms2g@virginia.edu> wrote:
> > ### This raises interesting questions - how did the
> > topology of the Universe
> > arise from the singularity? Is the initial condition
> > truly pointlike, or is
> > it a manifold or other structure with more complex
> > spatial organization?
>
> According to mathematician Roy Kerr, black holes
> inevitably crush down into rings.
Actually, the situation is more complicated than that. Collapsing stars
will likely end up in the Kerr metric (with a toroidal singularity
inside the event horizon) after shedding higher order moments through a
burst of gravity radiation. If you bring the hole's rotation to a stop
(by bombarding it with matter in the right way) the singularity turns
pointlike. But the universe doesn't have to have the same topology as
black holes.
Take a look at
http://www.maths.lse.ac.uk/Personal/mark/topos.pdf
http://darc.obspm.fr/~luminet/etopo.html
http://www.astro.princeton.edu/~dns/nas_neg/nas_neg.html
for some stuff about the topology of the universe.
> > How
> > can we try to deduce its features?
> >
> > Rafal
>
> by funding higher-energy particle accelerators to
> study what happens when quantum effects completely
> take over as would be the case in the first few
> moments of the big-bang. Right now any insights are
> just mathematical quirks.
No, this won't help. The topology of spacetime is not a local phenomenon,
you have to observe it at large scales to see anything.
-- ----------------------------------------------------------------------- Anders Sandberg Towards Ascension! asa@nada.kth.se http://www.nada.kth.se/~asa/ GCS/M/S/O d++ -p+ c++++ !l u+ e++ m++ s+/+ n--- h+/* f+ g+ w++ t+ r+ !y
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