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arXiv · hep-th/0310253

On open superstring partition function in inhomogeneous rolling tachyon background

A. Fotopoulos·A. A. Tseytlin
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Abstract

We consider open superstring partition function Z on the disc in time-dependent tachyon background T= f(x_i) e^{m x_0} where the profile function f depends on spatial coordinates. We compute Z to second order in derivatives of f and compare the result with some previously suggested effective actions depending only on the first derivatives of the tachyon field. We also compute the target-space stress-energy tensor in this background and demonstrate its conservation in the ``on-shell'' case of the linear profile f= f_0 + q_i x_i corresponding to a marginal perturbation. We comment on the role of the rolling tachyon with linear spatial profile in the decay of an unstable D-brane.

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A. Fotopoulos, A. A. Tseytlin. 2004-01-27. On open superstring partition function in inhomogeneous rolling tachyon background. https://doi.org/10.1088/1126-6708%2F2003%2F12%2F025

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