# Convex polytopes for the central degeneration of the affine Grassmannian

@article{Zhou2019ConvexPF, title={Convex polytopes for the central degeneration of the affine Grassmannian}, author={Qiao Zhou}, journal={Advances in Mathematics}, year={2019} }

We study the algebraic geometry and combinatorics of the central degeneration (the degeneration that shows up in local models of Shimura varieties and Gaitsgory's central sheaves) in type A. More specifically, we elucidate the central degeneration of semi-infinite orbits and explain its relations with Levi restriction. Also, we discuss the central degeneration of Mirkovi$\acute{\text{c}}$-Vilonen cycles in the affine Grassmannian, and the corresponding transformations of Mirkovi$\acute{\text{c…

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