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arXiv · 1307.3933

Unraveling gravity beyond Einstein with extended test bodies

Dirk Puetzfeld·Yuri N. Obukhov
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Abstract

The motion of test bodies in gravity is tightly linked to the conservation laws. This well-known fact in the context of General Relativity is also valid for gravitational theories which go beyond Einstein's theory. Here we derive the equations of motion for test bodies for a very large class of gravitational theories with a general nonminimal coupling to matter. These equations form the basis for future systematic tests of alternative gravity theories. Our treatment is covariant and generalizes the classic Mathisson-Papapetrou-Dixon result for spinning (extended) test bodies. The equations of motion for structureless test bodies turn out to be surprisingly simple, despite the very general nature of the theories considered.

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Dirk Puetzfeld, Yuri N. Obukhov. 2013-07-15. Unraveling gravity beyond Einstein with extended test bodies. https://doi.org/10.1016/j.physleta.2013.07.024

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