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arXiv · hep-th/9404191

On `rolling moduli' solutions in string cosmology

A. A. Tseytlin
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Abstract

Given a static string solution with some free constant parameters (`moduli') it may be possible to construct a time-dependent solution by just replacing the moduli by some functions of time. We present several examples when such `rolling moduli' ansatz is consistent. In particular, the anisotropic D=4 cosmological solution of Nappi and Witten can be reinterpreted as a time-dependent generalisation of the (analytic continuation of) D=3 `charged black string' background with the `charge' changing with time. We find some new D=4 cosmological solutions which are `two rolling moduli' generalisations of the previously known ones. We also comment on interplay between duality transformations and the replacement of moduli by functions of time.

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A. A. Tseytlin. 1994-05-01. On `rolling moduli' solutions in string cosmology. https://doi.org/10.1016/0370-2693(94)90695-5

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