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arXiv · hep-th/0303239

Off-shell extension of S-matrix elements and tachyonic effective actions

Mohammad R. Garousi
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Abstract

We show that the on-shell S-matrix elements of four open string massless scalars, two scalars and two tachyons, and four open string tachyons in the super string theory can be written in a unique form. We then propose an off-shell extension for the S-matrix element of four scalars which is consistent, in the low energy limit, with the Dirac-Born-Infeld effective action. Using a similar off-shell extension for the S-matrix element of two scalars and two tachyons and for the S-matrix element of four tachyons, we show that they are fully consistent with the tachyonic DBI action.

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Mohammad R. Garousi. 2003-05-10. Off-shell extension of S-matrix elements and tachyonic effective actions. https://doi.org/10.1088/1126-6708%2F2003%2F04%2F027

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