English

A Combinatorial Formula for Affine Hall-Littlewood Functions via a Weighted Brion Theorem

Combinatorics 2016-07-12 v4 Representation Theory

Abstract

We present a new combinatorial formula for Hall-Littlewood functions associated with the affine root system of type A~n1\tilde A_{n-1}, i.e. corresponding to the affine Lie algebra sl^n\hat{\mathfrak{sl}}_n. Our formula has the form of a sum over the elements of a basis constructed by Feigin, Jimbo, Loktev, Miwa and Mukhin in the corresponding irreducible representation. Our formula can be viewed as a weighted sum of exponentials of integer points in a certain infinite-dimensional convex polyhedron. We derive a weighted version of Brion's theorem and then apply it to our polyhedron to prove the formula.

Keywords

Cite

@article{arxiv.1505.04269,
  title  = {A Combinatorial Formula for Affine Hall-Littlewood Functions via a Weighted Brion Theorem},
  author = {Boris Feigin and Igor Makhlin},
  journal= {arXiv preprint arXiv:1505.04269},
  year   = {2016}
}