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Cosmological unification of string theories

Simeon Hellerman·Ian Swanson
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Abstract

We present an exact solution of superstring theory that interpolates in time between an initial type 0 phase and a final phase whose physics is exactly that of the bosonic string. The initial theory is deformed by closed-string tachyon condensation along a lightlike direction. In the limit of large tachyon vev, the worldsheet conformal field theory precisely realizes the Berkovits-Vafa embedding of bosonic string theory into superstring theory. Our solution therefore connects the bosonic string dynamically with the superstring, settling a longstanding question about the relationship between the two theories.

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Simeon Hellerman, Ian Swanson. 2008-06-14. Cosmological unification of string theories. https://doi.org/10.1088/1126-6708%2F2008%2F07%2F022

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