Abstract
Let X be a smooth variety over an algebraically closed field k of characteristic p, and let F: X → X be the Frobenius morphism. We prove that if X is an incidence variety (a partial flag variety in type A n ) or a smooth quadric (in this case p is supposed to be odd) then \( {H^i}\left( {X,\mathcal{E}nd\left( {{\sf{F}_*}{\mathcal{O}_X}} \right)} \right) = 0 \) for i > 0. Using this vanishing result and the derived localization theorem for crystalline differential operators [3], we show that the Frobenius direct image \( {\sf{F}_*}{\mathcal{O}_X} \) is a tilting bundle on these varieties provided that p > h, the Coxeter number of the corresponding group.
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Samokhin, A. A vanishing theorem for differential operators in positive characteristic. Transformation Groups 15, 227–242 (2010). https://doi.org/10.1007/s00031-010-9083-8
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DOI: https://doi.org/10.1007/s00031-010-9083-8