Paper: astro-ph/0509774
Date: Mon, 26 Sep 2005 15:31:44 GMT (15kb)

Title: A cosmological test for general relativity

Authors: Vincent Boucher

Categories: astro-ph

Comments: Proceedings of the International Conference on Cosmoparticle Physics
"Cosmion-2004", 20-24 September 2004, Paris

Report-no: UCL-IPT-05-01

Journal-ref: Gravitation & Cosmology, Vol. 11 (2005), No. 1-2 (41-42), pp. 71-74
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The effect of spatial variations of the Newton constant on the cosmic
microwave background is studied. Constraints on the strong equivalence
principle violation at the recombination time are then obtained with the help
of WMAP data and of the standard theory of big-bang nucleosynthesis.

\\ ( http://arXiv.org/abs/astro-ph/0509774 , 15kb)

Paper (*cross-listing*): gr-qc/0509094
Date: Fri, 23 Sep 2005 20:02:12 GMT (397kb)

Title: Numerical Relativity at the Frontier

Authors: Stuart L. Shapiro

Categories: gr-qc astro-ph

Comments: to appear in ``The Next Chapter in Einstein's Legacy'', Proceedings
of YKIS 2005, Kyoto, Japan, eds M. Sasaki, J. Soda and T. Tanaka, in Progress
of Theoretical Physics Suppl, in press (2006)
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Numerical relativity is an essential tool for solving Einstein's equations of
general relativity for dynamical systems characterized by high velocities and
strong gravitational fields. The implementation of new algorithms that can
solve these nonlinear equations in 3+1 dimensions has enabled us to tackle many
long-standing problems of astrophysical interest, leading to an explosion of
important new results. Numerical relativity has been used to simulate the
evolution of a diverse array of physical systems, including coalescing black
hole and neutron star binaries, rotating and collapsing compact objects (stars,
collisionless clusters, and scalar fields), and magnetic and viscous stars, to
name a few. Numerical relativity has been exploited to address fundamental
points of principle, including critical phenomena and cosmic censorship. It
holds great promise as a guide for interpreting observations of gravitational
waves and gamma-ray bursts and identifying the sources of such radiation.
Highlights of a few recent developments in numerical relativity are sketched in
this brief overview.

\\ ( http://arXiv.org/abs/gr-qc/0509094 , 397kb)