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arXiv · 0802.1658

Branes in hearts with perverse sheaves

Subir Mukhopadhyay·Koushik Ray
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Abstract

Various topological properties of D-branes in the type--IIA theory are captured by the topologically twisted B-model, treating D-branes as objects in the bounded derived category of coherent sheaves on the compact part of the target space. The set of basic D-branes wrapped on the homology cycles of the compact space are taken to reside in the heart of t-structures of the derived category of coherent sheaves on the space at any point in the Kähler moduli space. The stability data entails specifying a t-structure along with a grade for sorting the branes. Considering an example of a degenerate Calabi-Yau space, obtained via geometric engineering, that retains but a projective curve as the sole non-compact part, we identify the regions in the Kähler moduli space of the curve that pertain to the different t-structures of the bounded derived category of coherent sheaves on the curve corresponding to the different phases of the topological branes.

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Subir Mukhopadhyay, Koushik Ray. 2008-02-21. Branes in hearts with perverse sheaves. https://arxiv.org/abs/0802.1658

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