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arXiv · hep-th/0104126

Boundary Fermions, Coherent Sheaves and D-branes on Calabi-Yau manifolds

Suresh Govindarajan·T. Jayaraman
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Abstract

We construct boundary conditions in the gauged linear sigma model for B-type D-branes on Calabi-Yau manifolds that correspond to coherent sheaves given by the cohomology of a monad. This necessarily involves the introduction of boundary fields, and in particular, boundary fermions. The large-volume monodromy for these D-brane configurations is implemented by the introduction of boundary contact terms. We also discuss the construction of D-branes associated to coherent sheaves that are the cohomology of complexes of arbitrary length. We illustrate the construction using examples, specifically those associated with the large-volume analogues of the Recknagel-Schomerus states with no moduli. Using some of these examples we also construct D-brane states that arise as bound states of the above rigid configurations and show how moduli can be counted in these cases.

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Suresh Govindarajan, T. Jayaraman. 2001-04-19. Boundary Fermions, Coherent Sheaves and D-branes on Calabi-Yau manifolds. https://doi.org/10.1016/s0550-3213(01)00510-7

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