[extropy-chat] re: Dark matter galaxy discovered

[Hal Finney]

Speaking of dark energy (which is distinct from dark matter), the AAAS
meeting last week had a panel about it, described at
http://www.eurekalert.org/pub_releases/2005-02/uoc-sma021405.php .

Two "exotic" theories were discussed.  One is that string theory can
predict many different possible values for dark energy.  We have to
invoke the anthropic principle, which essentially says that we live in
a multiverse where different regions have different laws of physics.
Only in those regions where the dark energy allows for the universe to
last long enough, without recollapsing or tearing apart, can life evolve.
Hence we see that dark energy has the value it does.

Another one says that there is no dark energy at all.  It is an illusion.
Actually, in this model, gravity itself gets weaker at large distances
than Einsteinian (or Newtonian) theory would predict.  This gives the
illusion of a repulsive force which counteracts the pull of gravity,
that we interpret as dark energy.

Hal