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arXiv · 0902.3177

Obstructions and lines of marginal stability from the world-sheet

Ilka Brunner·Matthias R. Gaberdiel·Stefan Hohenegger·Christoph A. Keller
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Abstract

The behaviour of supersymmetric D-branes under deformations of the closed string background is studied using world-sheet methods. We explain how lines of marginal stability and obstructions arise from this point of view. We also show why N=2 B-type branes may be obstructed against (cc) perturbations, but why such obstructions do not occur for N=4 superconformal branes at c=6, i.e. for half-supersymmetric D-branes on K3. Our analysis is based on a field theory approach in superspace, as well as on techniques from perturbed conformal field theory.

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Ilka Brunner, Matthias R. Gaberdiel, Stefan Hohenegger, Christoph A. Keller. 2009-02-18. Obstructions and lines of marginal stability from the world-sheet. https://doi.org/10.1088/1126-6708%2F2009%2F05%2F007

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