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arXiv · 0907.4202

A Future Test of Gravitation Using Galaxy Cluster Velocities

Arthur Kosowsky·Suman Bhattacharya
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Abstract

The accelerating expansion of the Universe at recent epochs has called into question the validity of general relativity on cosmological scales. One probe of gravity is a comparison of expansion history of the Universe with the history of structure growth via gravitational instability: general relativity predicts a specific relation between these two observables. Here we show that the mean pairwise streaming velocity of galaxy clusters provides a useful method of constraining this relation. Galaxy cluster velocities can be measured via the kinetic Sunyaev-Zeldovich distortion of the cosmic microwave background radiation; future surveys can provide large enough catalogs of cluster velocities to discriminate between general relativity and other proposed gravitational theories.

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Arthur Kosowsky, Suman Bhattacharya. 2009-07-24. A Future Test of Gravitation Using Galaxy Cluster Velocities. https://doi.org/10.1103/physrevd.80.062003

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