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arXiv · hep-th/0412247

Closed string tachyon potential and $tt^*$ equation

Sunggeun Lee·Sang-Jin Sin
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Abstract

Recently Dabholkar and Vafa proposed that closed string tachyon potential for non-supersymmetric orbifold $\C/\Z_3$ in terms of the solution of a $tt^*$ equation. We extend this result to $\C^2/\Z_n$ for $n=3,4,5$. Interestingly, the tachyon potentials for $n=3$ and 4 are still given in terms of the solutions of Painleve III type equation that appeared in the study of $\C^1/\Z_3$ with different boundary conditions. For $\C^2/\Z_5$ case, governing equations are of generalized Toda type. The potential is monotonically decreasing function of RG flow.

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Sunggeun Lee, Sang-Jin Sin. 2005-03-29. Closed string tachyon potential and $tt^*$ equation. https://doi.org/10.1016/j.physletb.2005.03.069

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