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arXiv · 1410.8643

Anisotropic Power-law Inflation: A counter example to the cosmic no-hair conjecture

Jiro Soda
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Abstract

It is widely believed that anisotropy in the expansion of the universe will decay exponentially fast during inflation. This is often referred to as the cosmic no-hair conjecture. However, we find a counter example to the cosmic no-hair conjecture in the context of supergravity. As a demonstration, we present an exact anisotropic power-law inflationary solution which is an attractor in the phase space. We emphasize that anisotropic inflation is quite generic in the presence of anisotropic sources which couple with an inflaton.

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Jiro Soda. 2014-10-31. Anisotropic Power-law Inflation: A counter example to the cosmic no-hair conjecture. https://doi.org/10.1088/1742-6596%2F600%2F1%2F012026

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