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arXiv · 1302.4330

Cosmological Solutions of a Nonlocal Model with a Perfect Fluid

Emilio Elizalde·Ekaterina O. Pozdeeva·Sergey Yu. Vernov·Ying-li Zhang
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Abstract

A nonlocal gravity model which does not assume the existence of a new dimensional parameter in the action and includes a function $f(\Box^{-1} R)$, with $\Box$ the d'Alembertian operator, is studied. By specifying an exponential form for the function f and including a matter sector with a constant equation of state parameter, all available power-law solutions in the Jordan frame are obtained. New power-law solutions in the Einstein frame are also probed. Furthermore, the relationship between power-law solutions in both frames, established through conformal transformation, is substantially clarified. The correspondence between power-law solutions in these two frames is proven to be a very useful tool in order to obtain new solutions in the Einstein frame.

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Emilio Elizalde, Ekaterina O. Pozdeeva, Sergey Yu. Vernov, Ying-li Zhang. 2013-07-03. Cosmological Solutions of a Nonlocal Model with a Perfect Fluid. https://doi.org/10.1088/1475-7516%2F2013%2F07%2F034

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