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arXiv · 1403.1984

Phase Space of Anisotropic $R^n$ Cosmologies

Genly Leon
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Abstract

We construct general anisotropic cosmological scenarios governed by an $f(R)=R^n$ gravitational sector. Focusing then on some specific geometries, and modelling the matter content as a perfect fluid, we perform a phase-space analysis. We analyze the possibility of accelerating expansion at late times, and additionally, we determine conditions for the parameter $n$ for the existence of phantom behavior, contracting solutions as well as of cyclic cosmology. Furthermore, we analyze if the universe evolves towards the future isotropization without relying on a cosmic no-hair theorem. Our results indicate that anisotropic geometries in modified gravitational frameworks present radically different cosmological behaviors compared to the simple isotropic scenarios.

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Genly Leon. 2014-03-08. Phase Space of Anisotropic $R^n$ Cosmologies. https://doi.org/10.1142/s0218301311040037

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