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arXiv · 1712.03755

Anisotropic power-law inflation for a conformal-violating Maxwell model

Tuan Q. Do·W. F. Kao
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Abstract

A set of power-law solutions of a conformal-violating Maxwell model with a non-standard scalar-vector coupling will be shown in this paper. In particular, we are interested in a coupling term of the form $X^{2n} F^{μν}F_{μν}$ with $X$ denoting the kinetic term of the scalar field. Stability analysis indicates that the new set of anisotropic power-law solutions is unstable during the inflationary phase. The result is consistent with the cosmic no-hair conjecture. We show, however, that a set of stable slowly expanding solutions does exist for a small range of parameters $λ$ and $n$. Hence a small anisotropy can survive during the slowly expanding phase.

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Tuan Q. Do, W. F. Kao. 2017-12-11. Anisotropic power-law inflation for a conformal-violating Maxwell model. https://doi.org/10.1140/epjc%2Fs10052-018-5846-5

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