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arXiv · 1801.05319

Perverse schobers on Riemann surfaces: constructions and examples

W. Donovan
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Abstract

This note studies perverse sheaves of categories, or schobers, on Riemann surfaces, following ideas of Kapranov and Schechtman. For certain wall crossings in geometric invariant theory, I construct a schober on the complex plane, singular at each imaginary integer. I use this to obtain schobers for standard flops: in the 3-fold case, I relate these to a further schober on a partial compactification of a stringy Kaehler moduli space, and suggest an application to mirror symmetry.

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W. Donovan. 2018-01-16. Perverse schobers on Riemann surfaces: constructions and examples. https://arxiv.org/abs/1801.05319

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