Whittaker functions on metaplectic covers of GL(r)

Anna Puskás

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arXiv · 1605.05400

Whittaker functions on metaplectic covers of GL(r)

Anna Puskás

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Abstract

This paper establishes a combinatorial link between different approaches to constructing Whittaker functions on a metaplectic group over a non-archimedean local field. We prove a metaplectic analogue of Tokuyama's Theorem and give a crystal description of polynomials related to Iwahori-Whittaker functions. The proof relies on formulas of metaplectic Demazure and Demazure-Lusztig operators, proved previously in joint work with Gautam Chinta and Paul E. Gunnells.

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Anna Puskás. 2016-05-17. Whittaker functions on metaplectic covers of GL(r). https://arxiv.org/abs/1605.05400

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