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A tachyonic extension of the stringy no-go theorem

Swapna Mahapatra·Karmadeva Maharana·Lambodar P. Singh
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Abstract

We investigate the tachyon-dilaton-metric system to study the "graceful exit" problem in string theoretic inflation, where tachyon plays the role of the scalar field. From the phase space analysis, we find that the inflationary phase does not smoothly connect to a Friedmann-Robertson-Walker (FRW) expanding universe, thereby providing a simple tachyonic extension of the recently proved stringy no-go theorem.

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Swapna Mahapatra, Karmadeva Maharana, Lambodar P. Singh. 1997-02-27. A tachyonic extension of the stringy no-go theorem. https://doi.org/10.1103/physrevd.55.6600

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