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arXiv · 1306.5090

Cosmology with nonminimal kinetic coupling and a power-law potential

Maria A. Skugoreva·Sergey V. Sushkov·Alexei V. Toporensky
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Abstract

We consider cosmological dynamics in the theory of gravity with the scalar field possessing a nonminimal kinetic coupling to gravity, $\kappa G_{\mu\nu}\phi^{\mu}\phi^{\nu}$, and the power-law potential $V(\phi)=V_0\phi^N$. Using the dynamical system method, we analyze all possible asymptotical regimes of the model under investigation and show that for sloping potentials with $0 2. Using a numerical analysis, we also construct exact cosmological solutions and find initial conditions leading to the initial kinetic coupling inflation followed either by a "graceful" oscillatory exit or by the secondary inflation.

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Maria A. Skugoreva, Sergey V. Sushkov, Alexei V. Toporensky. 2013-06-21. Cosmology with nonminimal kinetic coupling and a power-law potential. https://doi.org/10.1103/physrevd.88.083539

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