From: Amara Graps (Amara.Graps@mpi-hd.mpg.de)
Date: Mon Apr 08 2002 - 05:19:24 MDT
A work by Barrow et al.
"It appears to be anthropically disadventageous for for a universe to
be too close to flatness or for the cosmological constant to be too
close to zero."
http://xxx.lanl.gov/abs/astro-ph/0110497
Astrophysics, abstract
astro-ph/0110497
From: Havard B. Sandvik <h.sandvik@ic.ac.uk>
Date (v1): Mon, 22 Oct 2001 20:38:01 GMT (99kb)
Date (revised v2): Fri, 5 Apr 2002 15:12:07 GMT (100kb)
Anthropic Reasons for Non-Zero Flatness and Lambda
Authors: J.D. Barrow, H.B. Sandvik, J. Magueijo
Comments: 7 pages, 5 figures, Corrected sign error and made necessary
modifications. This version is accepted for publication in Phys.Rev.D
Subj-class: Astrophysics; Popular Physics
In some cosmological theories with varying constants there are
anthropic reasons why the expansion of the universe must not be
too {\it close} to flatness or the cosmological constant too close
to zero. Using exact theories which incorporate time-variations in
$\alpha $ and in $G$ we show how the presence of negative spatial
curvature and a positive cosmological constant play an essential
role in bringing to an end variations in the scalar fields driving
time change in these 'constants' during any dust-dominated era of
a universe's expansion. In spatially flat universes with $\Lambda
=0$ the fine structure constant grows to a value which makes the
existence of atoms impossible.
Paper: PostScript, PDF, or Other formats
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.DE addresses: Nearest e-print mirror site is http://de.arXiv.org/
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Amara Graps, PhD | Max-Planck-Institut fuer Kernphysik
Heidelberg Cosmic Dust Group | Saupfercheckweg 1
+49-6221-516-543 | 69117 Heidelberg, GERMANY
Amara.Graps@mpi-hd.mpg.de * http://www.mpi-hd.mpg.de/dustgroup/~graps
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