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D-brane effective action and tachyon condensation in topological minimal models

Manfred Herbst·Calin-Iuliu Lazaroiu·Wolfgang Lerche
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Abstract

We study D-brane moduli spaces and tachyon condensation in B-type topological minimal models and their massive deformations. We show that any B-type brane is isomorphic with a direct sum of `minimal' branes, and that its moduli space is stratified according to the type of such decompositions. Using the Landau-Ginzburg formulation, we propose a closed formula for the effective deformation potential, defined as the generating function of tree-level open string amplitudes in the presence of D-branes. This provides a direct link to the categorical description, and can be formulated in terms of holomorphic matrix models. We also check that the critical locus of this potential reproduces the D-branes' moduli space as expected from general considerations. Using these tools, we perform a detailed analysis of a few examples, for which we obtain a complete algebro-geometric description of moduli spaces and strata.

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Manfred Herbst, Calin-Iuliu Lazaroiu, Wolfgang Lerche. 2004-05-15. D-brane effective action and tachyon condensation in topological minimal models. https://doi.org/10.1088/1126-6708%2F2005%2F03%2F078

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