> John K Clark wrote:
> > I think most would say the universe is probably open and so will never
> > collapse. Even Tipler thinks the universe is ALMOST open and so will take a
> > very long time before it starts to collapse, 10^18 years. So according to
> > Tipler The Omega Point will happen in 2 * 10^18 years, give or take a few
> > hundred trillion. That's a very large number to be sure, but it's no closer
> > to being infinite than the number 1 is.
> >
> John, how does this relate to the rate of proton decay? Will all the
> matter in the universe evaporate before it starts to collapse again?
According to the physics book I read last, the experiments that looked
for proton decay didn't find any, so the halflife is longer than 10^31
years as predicted by SU(5) (which hence is falsified). So in Tipler's
scenario we will still enjoy protons up to the final moments.
I have been working a bit on the Dyson scenario (slow, cold life in an open
universe), and there we have to deal with baryonic decay (if matter is stable
it will still decay to black holes sooner or later, which then evaporate into
leptons). Does anybody have a serious idea of how to implement life in a
substrate of electrons, positrons, photons and neutrinos? Billiard ball
computers?
I have looked at the energy costs of reversible life, and so far it looks
good: the integral of the energy demands of error correction stays finite as
t->inf. The trouble is redshifting of message photons and the energy costs of
making more memory. I'll get back to that...
Another thing I would like to hear opinions on: can a part of spacetime
be collapsed into something like a closed universe (i.e. not a black hole
singularity)?
-----------------------------------------------------------------------
Anders Sandberg Towards Ascension!
nv91-asa@nada.kth.se http://www.nada.kth.se/~nv91-asa/main.html
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