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arXiv · 1201.5127

The Direction of Gravity

Eric V. Linder
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Abstract

Gravity directs the paths of light rays and the growth of structure. Moreover, gravity on cosmological scales does not simply point down: it accelerates the universal expansion by pulling outward, either due to a highly negative pressure dark energy or an extension of general relativity. We examine methods to test the properties of gravity through cosmological measurements. We then consider specific possibilities for a sound gravitational theory based on the Galileon shift symmetry. The evolution of the laws of gravity from the early universe to the present acceleration to the future fate -- the paths of gravity -- carries rich information on this fundamental force of physics and on the mystery of dark energy.

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Eric V. Linder. 2012-01-24. The Direction of Gravity. https://doi.org/10.1088/1742-6596/484/1/012006

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