From: LARRY KLAES (ljk4_at_msn.com)
Date: Tue Oct 04 2005 - 19:50:29 UTC
Paper: astro-ph/0510024
Date: Sun, 2 Oct 2005 19:22:16 GMT (16kb)
Title: Dark energy - dark matter - and black holes: The music of the
universe
Authors: Peter L. Biermann (Max Planck Institute for Radioastronomy, Bonn,
Germany)
Categories: astro-ph
Comments: 8 pages, Invited review lecture at Carpathian Summer School in
Physics 2005 (CSSP2005)
\\
Here we review the recent evidence for dark energy, dark matter and black
holes as components of an expanding universe, for the vantage point of a
non-expert; we speculate on a specific DM particle.
\\ ( http://arXiv.org/abs/astro-ph/0510024 , 16kb)
Paper: astro-ph/0510059
Date: Mon, 3 Oct 2005 19:45:26 GMT (105kb)
Title: Insights into Dark Energy: Interplay Between Theory and Observation
Authors: Rachel Bean, Sean Carroll and Mark Trodden
Categories: astro-ph
Comments: White paper submitted to the Dark Energy Task Force, 5 pages + 2
pages references, 2 figures
\\
The nature of Dark Energy is still very much a mystery, and the combination
of a variety of experimental tests, sensitive to different potential Dark
Energy properties, will help elucidate its origins. This white paper briefly
surveys the array of theoretical approaches to the Dark Energy problem and
their relation to experimental questions.
\\ ( http://arXiv.org/abs/astro-ph/0510059 , 105kb)
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Paper (*cross-listing*): gr-qc/0509124
Date: Fri, 30 Sep 2005 13:37:25 GMT (37kb)
Title: On globally static and stationary cosmologies with or without a
cosmological constant and the Dark Energy problem
Authors: Thomas Buchert
Categories: gr-qc astro-ph
Comments: 33 pages, submitted version
\\
In the framework of spatially averaged inhomogeneous cosmologies in
classical
General Relativity, effective Einstein equations govern the regional and the
global dynamics of averaged scalar variables of cosmological models. A
particular solution may be characterized by a cosmic equation of state. In
this
paper it is pointed out that a globally static averaged dust model is
conceivable without employing a compensating cosmological constant. Much in
the
spirit of Einstein's original model we discuss consequences for the global,
but
also for the regional properties of this cosmology. We then consider the
wider
class of globally stationary cosmologies that are conceivable in the
presented
framework. All these models are based on exact solutions of the averaged
Einstein equations and provide examples of cosmologies in an
out-of-equilibrium
state, which we characterize by an information-theoretical measure. It is
shown
that such cosmologies preserve high-magnitude kinematical fluctuations and
so
tend to maintain their global properties. The same is true for a
$\Lambda-$driven cosmos in such a state despite of exponential expansion. We
outline relations to inflationary scenarios, and put the Dark Energy problem
into perspective. Here, it is argued, on the grounds of the discussed
cosmologies, that a classical explanation of Dark Energy through
backreaction
effects is theoretically conceivable, if the matter-dominated Universe
emerged
from a non-perturbative state in the vicinity of the stationary solution. We
also discuss a number of caveats that furnish strong counter arguments in
the
framework of structure formation in a perturbed Friedmannian model.
\\ ( http://arXiv.org/abs/gr-qc/0509124 , 37kb)
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