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arXiv · 1309.6756

The universe dominated by oscillating scalar with non-minimal derivative coupling to gravity

Ryusuke Jinno·Kyohei Mukaida·Kazunori Nakayama
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Abstract

We study the expansion law of the universe dominated by the oscillating scalar field with non-minimal derivative coupling to gravity as G^{μν} \partial_μ ϕ\partial_ν ϕ. In this system the Hubble parameter oscillates with a frequency of the effective mass of the scalar field, which formerly caused a difficulty in analyzing how the universe expands. We find an analytical solution for power law potentials and interpret the solution in an intuitive way by using a new invariant of the system. As a result, we find marginally accelerated expansion for the quadratic potential and no accelerated expansion for the potential with higher power.

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Ryusuke Jinno, Kyohei Mukaida, Kazunori Nakayama. 2013-09-26. The universe dominated by oscillating scalar with non-minimal derivative coupling to gravity. https://doi.org/10.1088/1475-7516%2F2014%2F01%2F031

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