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arXiv · 2505.17953

Modular intersection cohomology of Drinfeld's compactifications

Pramod N. Achar·Gurbir Dhillon·Simon Riche
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Abstract

We compute the dimension of the cohomology of stalks of intersection cohomology complexes on Zastava schemes and Drinfeld compactifications associated with a connected reductive algebraic group $G$, in case the characteristic of the coefficients field $\Bbbk$ is good for $G$. In particular, we show that these dimensions do not depend on the choice of $\Bbbk$.

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BibTeXRIS

Pramod N. Achar, Gurbir Dhillon, Simon Riche. 2025-05-23. Modular intersection cohomology of Drinfeld's compactifications. https://arxiv.org/abs/2505.17953

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