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arXiv · hep-th/0003122

Tachyon couplings on non-BPS D-branes and Dirac-Born-Infeld action

Mohammad R. Garousi
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Abstract

By explicit evaluation of certain disk S-matrix elements in the presence of background B-flux, we find coupling of two open string tachyons to gauge field, graviton, dilaton or Kalb-Ramond antisymmetric tensor on the world-volume of a single non-BPS D$p$-brane. We then propose an extension of the abelian Dirac-Born-Infeld action which naturally reproduces these couplings in field theory. This action includes non-linearly the dynamics of the tachyon field much like the other bosonic modes of the non-BPS D$p$-brane. On the general grounds of gauge and T-duality transformations and the symmetrized trace prescription, we then extend the abelian action to non-abelian cases.

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Mohammad R. Garousi. 2000-03-15. Tachyon couplings on non-BPS D-branes and Dirac-Born-Infeld action. https://doi.org/10.1016/s0550-3213(00)00361-8

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