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Exponential-Potential Scalar Field Universes II: The Inhomogeneous Models

J. M. Aguirregabiria·A. Feinstein·J. Ibanez
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Abstract

We obtain exact solutions for the Einstein equations with an exponential-potential scalar field (\(V=Λe^{kϕ}\)) which represent simple inhomogeneous generalizations of Bianchi I cosmologies. Studying these equations numerically we find that in most of the cases there is a certain period of inflationary behaviour for \(k^2<2\). We as well find that for \(k^2>2\) the solutions homogenize generically at late times. Yet, {\em none of the solutions} isotropize. For some particular values of the integration constants we find a multiple inflationary behaviour for which the deceleration and the inflationary phases interchange each other several times during the history of the model.

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J. M. Aguirregabiria, A. Feinstein, J. Ibanez. 1993-09-14. Exponential-Potential Scalar Field Universes II: The Inhomogeneous Models. https://doi.org/10.1103/physrevd.48.4669

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