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arXiv · 1612.04239

Unified cosmology with Non-minimally coupled scalar-tensor theory of gravity

Behzad Tajahmad·Abhik Kumar Sanyal
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Abstract

Unlike Noether symmetry, a metric independent general conserved current exits for non-minimally coupled scalar-tensor theory of gravity, if the trace of the energy momentum tensor vanishes. Thus, in the context of cosmology, a symmetry exists both in the early vacuum and radiation dominated era. For slow roll, symmetry is sacrificed, but at the end of early inflation, such a symmetry leads to a Friedmann-like radiation era. Late time cosmic acceleration in the matter dominated era is realized in the absence of symmetry, in view of the same decayed and red-shifted scalar field. Thus, unification of early inflation with late time cosmic acceleration with a single scalar field, may be realized.

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Behzad Tajahmad, Abhik Kumar Sanyal. 2016-12-09. Unified cosmology with Non-minimally coupled scalar-tensor theory of gravity. https://doi.org/10.1140/epjc%2Fs10052-017-4785-x

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