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N=1 Worldsheet Boundary Couplings and Covariance of non-Abelian Worldvolume Theory

S. F. Hassan
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Abstract

A systematic construction is given for N=1 open string boundary coupling to Abelian and non-Abelian Dp-brane worldvolume fields, in general curved backgrounds. The basic ingredient is a set of four ``boundary vectors'' that provide a unified description of boundary conditions and boundary couplings. We then turn to the problem of apparent inconsistency of non-Abelian worldvolume scalar couplings (obtained by T-duality), with general covariance. It means that the couplings cannot be obtained from a covariant action by gauge fixing ordinary general coordinate transformations (GCT). It is shown that the corresponding worldsheet theory has the same problem, but is also invariant under certain matrix-valued coordinate transformations (MCT) that can be used to restore its covariance. The same transformations act on the worldvolume, leading to a covariant action. Then the non-Abelian Dp-brane action obtained by T-duality corresponds to gauge fixing the MCT and not GCT, hence the apparent incompatibility with general covariance.

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S. F. Hassan. 2003-08-28. N=1 Worldsheet Boundary Couplings and Covariance of non-Abelian Worldvolume Theory. https://arxiv.org/abs/hep-th/0308201

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