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arXiv · hep-th/0507159

D-branes in Lie groups of rank > 1

Samuel Monnier
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Abstract

We consider a low-energy effective action for the gauge field on Wess-Zumino-Witten D-branes in a compact simple Lie group, in the limit of large k. We prove that the effective action is bounded from below, and study stability of various D-brane configurations, including some class of non-maximally symmetric ones. We show that for Lie groups of rank higher than one, the D-brane ground state breaks the Kac-Moody symmetry of the boundary theory. We then give arguments hinting that the "fuzzy sphere" D2-brane which is known to be the stable brane configuration in the case of SU(2), may also correspond to the ground state in other compact simple Lie groups.

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Samuel Monnier. 2005-10-05. D-branes in Lie groups of rank > 1. https://doi.org/10.1088/1126-6708%2F2005%2F08%2F062

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