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arXiv · 0902.2833

Inflationary Universe with Anisotropic Hair

Masa-aki Watanabe·Sugumi Kanno·Jiro Soda
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Abstract

We study an inflationary scenario with a vector field coupled with an inflaton field and show that the inflationary universe is endowed with anisotropy for a wide range of coupling functions. This anisotropic inflation is a tracking solution where the energy density of the vector field follows that of the inflaton field irrespective of initial conditions. We find a universal relation between the anisotropy and a slow-roll parameter of inflation. Our finding has observational implications and gives a counter example to the cosmic no-hair conjecture.

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Masa-aki Watanabe, Sugumi Kanno, Jiro Soda. 2009-04-30. Inflationary Universe with Anisotropic Hair. https://doi.org/10.1103/physrevlett.102.191302

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