English

Weight $q$-multiplicities for representations of the exceptional Lie algebra $\mathfrak{g}_2$

Representation Theory 2020-03-31 v2 Combinatorics

Abstract

Given a simple Lie algebra g\mathfrak{g}, Kostant's weight qq-multiplicity formula is an alternating sum over the Weyl group whose terms involve the qq-analog of Kostant's partition function. For ξ\xi (a weight of g\mathfrak{g}), the qq-analog of Kostant's partition function is a polynomial-valued function defined by q(ξ)=ciqi\wp_q(\xi)=\sum c_i q^i where cic_i is the number of ways ξ\xi can be written as a sum of ii positive roots of g\mathfrak{g}. In this way, the evaluation of Kostant's weight qq-multiplicity formula at q=1q = 1 recovers the multiplicity of a weight in a highest weight representation of g\mathfrak{g}. In this paper, we give closed formulas for computing weight qq-multiplicities in a highest weight representation of the exceptional Lie algebra g2\mathfrak{g}_2.

Keywords

Cite

@article{arxiv.2003.07814,
  title  = {Weight $q$-multiplicities for representations of the exceptional Lie algebra $\mathfrak{g}_2$},
  author = {Jerrell Cockerham and Melissa Gutiérrez González and Pamela E. Harris and Marissa Loving and Amaury V. Miniño and Joseph Rennie and Gordon Rojas Kirby},
  journal= {arXiv preprint arXiv:2003.07814},
  year   = {2020}
}

Comments

17 pages, 1 figure, tables