On particle creation/decay in nonminimally coupled models of gravity. (arXiv:1901.06299v1 [gr-qc])
<a href="http://arxiv.org/find/gr-qc/1/au:+Azevedo_R/0/1/0/all/0/1">R.P.L. Azevedo</a>, <a href="http://arxiv.org/find/gr-qc/1/au:+Avelino_P/0/1/0/all/0/1">P.P. Avelino</a>
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.
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.
http://arxiv.org/icons/sfx.gif
