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Perverse coherent sheaves (after Deligne)

Roman Bezrukavnikov
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Abstract

This note is mostly an exposition of an unpublished result of Deligne, which introduces an analogue of perverse $t$-structure on the derived category of coherent sheaves on a Noetherian scheme with a dualizing complex. Construction extends to the category of coherent sheaves equivariant under an action of an algebraic group; though proof of the general statement in this case does not require new ideas, it provides examples (such as sheaves on the nilpotent cone of a semi-simple group equivariant under the adjoint action) where construction of coherent "intersection cohomology" sheaves works.

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Roman Bezrukavnikov. 2000-05-16. Perverse coherent sheaves (after Deligne). https://arxiv.org/abs/math/0005152

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