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arXiv · 0903.5297

Impact of Lorentz violation on the dynamics of inflation

P. P. Avelino·D. Bazeia·L. Losano·R. Menezes·J. J. Rodrigues
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Abstract

This work deals with the dynamics of inflation in the context of a scalar-vector-tensor theory of gravity exhibiting spontaneous Lorentz violation at early times. We describe a first-order formalism which we use to obtain new exact Lorentz violating inflationary solutions for a broad family of models, some in the absence of a potential for the inflaton field. Our results show that different conditions are required to solve the horizon and flatness problems. In particular, we find a necessary condition for inflation to provide a solution to both problems and we show that in inflationary models with no inflaton potential a period of superinflation might be necessary to solve the flatness problem.

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P. P. Avelino, D. Bazeia, L. Losano, R. Menezes, J. J. Rodrigues. 2009-03-30. Impact of Lorentz violation on the dynamics of inflation. https://doi.org/10.1103/physrevd.79.123503

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