Non-abelian expansion of S-matrix elements and non-abelian tachyon DBI action

Kazem Bitaghsir-Fadafan; Mohammad R. Garousi

doi:10.1016/j.nuclphysb.2006.10.015

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arXiv · hep-th/0607249

Non-abelian expansion of S-matrix elements and non-abelian tachyon DBI action

Kazem Bitaghsir-Fadafan·Mohammad R. Garousi

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Abstract

We apply the prescription proposed in hep-th/0307197 for non-abelian expansion of S-matrix elements, to the S-matrix element of four tachyons and one gauge field in superstring theory. We show that the leading order terms of the expansion are in perfect agreement with the non-abelian generalization of the tachyon DBI action in which the tachyon potential is $V(T)=1+πα' m^2T^2+\frac{1}{2!}(πα' m^2T^2)^2+...$ where $m^2=-1/(2α')$ is the mass of tachyon. This calculation fixes the coefficient of $T^4$ in the potential without on-shell ambiguity.

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Kazem Bitaghsir-Fadafan, Mohammad R. Garousi. 2006-10-21. Non-abelian expansion of S-matrix elements and non-abelian tachyon DBI action. https://doi.org/10.1016/j.nuclphysb.2006.10.015

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