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Numerical Study of Inhomogeneous Pre-Big-Bang Inflationary Cosmology

Takeshi Chiba
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Abstract

We study numerically the inhomogeneous pre-big-bang inflation in a spherically symmetric space-time. We find that a large initial inhomogeneity suppresses the onset of the pre-big-bang inflation. We also find that even if the pre-big-bang inflationary stage is realized, the initial inhomogeneities are not homogenized. Namely, during the pre-big-bang inflation ``hairs''(irregularities) do not fall, in sharp contrast to the usual (potential energy dominated) inflation where initial inhomogeneity and anisotropy are damped and thus the resulting universe is less sensitive to initial conditions.

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Takeshi Chiba. 1999-02-01. Numerical Study of Inhomogeneous Pre-Big-Bang Inflationary Cosmology. https://doi.org/10.1103/physrevd.59.083508

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