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arXiv · 2011.05891

Quasi-geodesics in relativistic gravity

Valerio Faraoni·Geneviève Vachon
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Abstract

A four-force parallel to the trajectory of a massive particle can always be eliminated by going to an affine parametrization, but the affine parameter is different from the proper time. The main application is to cosmology, in which elements of the cosmic fluid are subject to a pressure gradient parallel to their four-velocities. Natural implementations of parallel four-forces occur when the particle mass changes and in scalar-tensor cosmology.

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Valerio Faraoni, Geneviève Vachon. 2020-11-11. Quasi-geodesics in relativistic gravity. https://doi.org/10.1140/epjc%2Fs10052-020-08808-9

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