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arXiv · hep-th/0105174

Wound D-branes in Gepner Models

Shun'ya Mizoguchi·Taro Tani
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Abstract

We propose a new prescription of how to represent D-branes in Gepner models in more general homology classes than those in the previous constructions. The central role is played by a certain projection acting on the Recknagel-Schomerus boundary states. Consequently, the boundary states are in most cases no longer a sum of products of N=2 Ishibashi states, but nevertheless preserve spacetime supersymmetry and satisfy the Cardy condition. We demonstrate these in the (k=1)^3 Gepner model in detail, and construct boundary states for D-branes wound around arbitrary rigid 1-cycles on the corresponding 2-torus. We also emphasize the necessity of some angle-dependent transformations in identifying a proper free-field realization for each brane tilted at an angle. In particular, this is essential for the Witten index to give the correct intersection numbers between the different D-branes.

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Shun'ya Mizoguchi, Taro Tani. 2001-05-18. Wound D-branes in Gepner Models. https://doi.org/10.1016/s0550-3213(01)00359-5

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