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arXiv · hep-th/0408124

On Solvable Time-Dependent Model and Rolling Closed String Tachyon

Yasuaki Hikida·Tadashi Takayanagi
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Abstract

We investigate the SL(2,R)/U(1) WZW model with level 0<k<2 as a solvable time-dependent background in string theory. This model is expected to be dual to the one describing a rolling closed string tachyon with a time-like linear dilaton. We examine its exact metric and minisuperspace wave functions. Two point functions and the one-loop vacuum amplitude are computed and their relation to the closed string emission is discussed. Comparing with the results from the minisuperspace approximation, we find a physical interpretation of our choice to continue the Euclidean model into the Lorentzian one. Three point functions are also examined.

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Yasuaki Hikida, Tadashi Takayanagi. 2004-12-09. On Solvable Time-Dependent Model and Rolling Closed String Tachyon. https://doi.org/10.1103/physrevd.70.126013

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