Extending torsors on the punctured Spec(A_inf)

2018/04/17 by Johannes Anschütz, Anschütz, Johannes · 1 citation
Mathematics · #11E39 #11E72 #14G20 #Algebraic Geometry and Number Theory #Algebraic structures and combinatorial models #FOS: Mathematics #Homotopy and Cohomology in Algebraic Topology #Number Theory (math.NT)

paper · pdf · doi:10.48550/arxiv.1804.06356

openalex publication_date 2018/04/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/04

Abstract

We prove that torsors under parahoric group schemes on the punctured spectrum of Fontaine's ring A_inf, extend to the whole spectrum. Using descent we can extend a similar result for the ring \mathfrakS of Kisin and Pappas to full generality. Moreover, we treat similarly the case of equal characteristic. As applications we extend results of Ivanov on exactness of the loop functor and present the construction of a canonical specialization map from the B⁺_dR-affine Grassmannian to the Witt vector affine flag variety.

Citations

• The generic fiber of moduli spaces of bounded local G-shtukas
• Functoriality of Moduli Spaces of Global \mathbb G-Shtukas

Cited by

• Strongly compatible systems associated to semistable abelian varieties

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