Nearby cycles for parity sheaves on a divisor with simple normal\n crossings

2018/12/19 by Pramod N. Achar, Achar, Pramod N., Laura Rider +1
Mathematics · #Advanced Algebra and Geometry #Algebraic Geometry (math.AG) #Algebraic Geometry and Number Theory #FOS: Mathematics #Homotopy and Cohomology in Algebraic Topology #Representation Theory (math.RT)

paper · pdf · doi:10.48550/arxiv.1812.07924

openalex publication_date 2018/12/19 · openalex created_date 2022/08/01 · openalex updated_date 2026/07/28

Abstract

The first author recently introduced a "nearby cycles formalism" in the\nframework of chain complexes of parity sheaves. In this paper, we compute this\nfunctor in two related settings: (i) affine space, stratified by the action of\na torus, and (ii) the global Schubert variety associated to the first\nfundamental coweight of the group PGL_n. The latter is a parity-sheaf\nanalogue of Gaitsgory's central sheaf construction.\n

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