Testing Gravity with the Stacked Phase Space around Galaxy Clusters
Cosmology and Nongalactic Astrophysics
2013-05-30 v2
Abstract
In General Relativity, the average velocity field of dark matter around galaxy clusters is uniquely determined by the mass profile. The latter can be measured through weak lensing. We propose a new method of measuring the velocity field (phase space density) by stacking redshifts of surrounding galaxies from a spectroscopic sample. In combination with lensing, this yields a direct test of gravity on scales of 1-30 Mpc. Using N-body simulations, we show that this method can improve upon current constraints on f(R) and DGP model parameters by several orders of magnitude when applied to upcoming imaging and redshift surveys.
Cite
@article{arxiv.1202.4501,
title = {Testing Gravity with the Stacked Phase Space around Galaxy Clusters},
author = {Tsz Yan Lam and Takahiro Nishimichi and Fabian Schmidt and Masahiro Takada},
journal= {arXiv preprint arXiv:1202.4501},
year = {2013}
}
Comments
4 pages, 3 figures. Match version accepted by PRL