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arXiv · 0710.5155

Cosmological model with non-minimally coupled fermionic field

M. O. Ribas·F. P. Devecchi·G. M. Kremer
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Abstract

A model for the Universe is proposed whose constituents are: (a) a dark energy field modeled by a fermionic field non-minimally coupled with the gravitational field, (b) a matter field which consists of pressureless baryonic and dark matter fields and (c) a field which represents the radiation and the neutrinos. The coupled system of Dirac's equations and Einstein field equations is solved numerically by considering a spatially flat homogeneous and isotropic Universe. It is shown that the proposed model can reproduce the expected red-shift behaviors of the deceleration parameter, of the density parameters of each constituent and of the luminosity distance. Furthermore, for small values of the red-shift the constant which couples the fermionic and gravitational fields has a remarkable influence on the density and deceleration parameters.

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M. O. Ribas, F. P. Devecchi, G. M. Kremer. 2007-10-26. Cosmological model with non-minimally coupled fermionic field. https://doi.org/10.1209/0295-5075/81/19001

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