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GEOMETRY OF KOTTWITZ–VIEHMANN VARIETIES

Published online by Cambridge University Press:  08 November 2019

Jingren Chi*
Affiliation:
Department of Mathematics, University of Maryland, College Park, MD20742, USA (chijingren@gmail.com)

Abstract

We study basic geometric properties of Kottwitz–Viehmann varieties, which are certain generalizations of affine Springer fibers that encode orbital integrals of spherical Hecke functions. Based on the previous work of A. Bouthier and the author, we show that these varieties are equidimensional and give a precise formula for their dimension. Also we give a conjectural description of their number of irreducible components in terms of certain weight multiplicities of the Langlands dual group and we prove the conjecture in the case of unramified conjugacy class.

Type
Research Article
Copyright
© Cambridge University Press 2019

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