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arXiv · 1901.06299

Particle creation and decay in nonminimally coupled models of gravity

R. P. L. Azevedo·P. P. Avelino
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Abstract

In extended models of gravity a nonminimal coupling to matter has been assumed to lead to irreversible particle creation. In this paper we challenge this assumption. We argue that a non-minimal coupling of the matter and gravitational sectors results in a change in particle-momentum on a cosmological timescale, irrespective of particle creation or decay. We further argue that particle creation or decay associated with a non-minimal coupling to gravity could only happen as a result of significant deviations from a homogeneous Friedmann-Robertson-Walker geometry on microscopic scales, and provide a phenomenological description of the impact of particle creation or decay on the cosmological evolution of the density of the matter fields.

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R. P. L. Azevedo, P. P. Avelino. 2019-01-18. Particle creation and decay in nonminimally coupled models of gravity. https://doi.org/10.1103/physrevd.99.064027

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