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arXiv · 1807.01929

Characteristic cycles and the microlocal geometry of the Gauss map, II

Thomas Krämer
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Abstract

We show that for the reductive Tannaka groups of semisimple holonomic $\mathscr{D}$-modules on abelian varieties, every Weyl group orbit of weights of their universal cover is realized by a conic Lagrangian cycle on the cotangent bundle. Applications include a weak solution to the Schottky problem in genus five, an obstruction for the existence of summands of subvarieties on abelian varieties and a criterion for the simplicity of the arising Lie algebras.

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Thomas Krämer. 2018-07-05. Characteristic cycles and the microlocal geometry of the Gauss map, II. https://doi.org/10.1515/crelle-2020-0048

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