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arXiv · 1903.01781

Non-minimally coupled nonlinear spinor field in Bianchi type-I cosmology

Bijan Saha
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Abstract

Within the scope of Bianchi type-$I$ cosmological model we have studied the role of spinor field in the evolution of the Universe. In doing so we have considered the case with non-minimal coupling. It was found that the non-diagonal components of the energy-momentum tensor of the spinor field, hence the restrictions on the space-time geometry remain the same as in case of minimal coupling. Since in this case the diagonal components of the energy-momentum tensor differ, the evolution of the corresponding universe also differs. For example, while a linear spinor field with non-minimal coupling or nonlinear spinor field with minimal coupling give rise to open universe, a nonlinear spinor field with non-minimal coupling with the same parameters can generate close universe that at the beginning expands, and after attaining some maximum value begin to contract and finally ends in a Big Crunch.

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Bijan Saha. 2019-03-05. Non-minimally coupled nonlinear spinor field in Bianchi type-I cosmology. https://doi.org/10.1140/epjp/i2019-12859-7

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