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arXiv · 2406.09218

Cohomological integrality for weakly symmetric representations of reductive groups

Lucien Hennecart
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Abstract

In this paper, we prove the integrality conjecture for quotient stacks arising from weakly symmetric representations of reductive groups. Our main result is a decomposition of the cohomology of the stack into finite-dimensional components indexed by some equivalence classes of cocharacters of a maximal torus. This decomposition enables the definition of new enumerative invariants associated with the stack, which we begin to explore.

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BibTeXRIS

Lucien Hennecart. 2024-06-13. Cohomological integrality for weakly symmetric representations of reductive groups. https://doi.org/10.1017/s1474748025101357

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