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arXiv · 1201.6434

Statistical Anisotropy from Anisotropic Inflation

Jiro Soda
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Abstract

We review an inflationary scenario with the anisotropic expansion rate. An anisotropic inflationary universe can be realized by a vector field coupled with an inflaton, which can be regarded as a counter example to the cosmic no-hair conjecture. We show generality of anisotropic inflation and derive a universal property. We formulate cosmological perturbation theory in anisotropic inflation. Using the formalism, we show anisotropic inflation gives rise to the statistical anisotropy in primordial fluctuations. We also explain a method to test anisotropic inflation using the cosmic microwave background radiation (CMB).

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Jiro Soda. 2012-03-07. Statistical Anisotropy from Anisotropic Inflation. https://doi.org/10.1088/0264-9381%2F29%2F8%2F083001

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