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arXiv · 0706.1775

Galaxy-CMB Cross-Correlation as a Probe of Alternative Models of Gravity

Fabian Schmidt·Michele Liguori·Scott Dodelson
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Abstract

Bekenstein's alternative to general relativity, TeVeS, reduces to Modified Newtonian Dynamics (MOND) in the galactic limit. On cosmological scales, the (potential well <-> overdensity) relationship is quite different than in standard general relativity. Here we investigate the possibility of cross-correlating galaxies with the cosmic microwave background (CMB) to probe this relationship. At redshifts of order 2, the sign of the CMB-galaxy correlation differs in TeVeS from that in general relativity. We show that this effect is detectable and hence can serve as a powerful discriminator of these two models of gravity.

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Fabian Schmidt, Michele Liguori, Scott Dodelson. 2007-08-30. Galaxy-CMB Cross-Correlation as a Probe of Alternative Models of Gravity. https://doi.org/10.1103/physrevd.76.083518

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