English

On the quantum Horn problem

Algebraic Geometry 2013-10-29 v1

Abstract

Let KK be a compact, connected, simply-connected simple Lie group. Given two conjugacy classes \Orb1\Orb_1 and \Orb2\Orb_2 in KK, we consider the multiplicative Horn question: What conjugacy classes are contained in \Orb1\Orb2\Orb_1\cdot\Orb_2? It is known that answering this question remains to describe a convex polytope \polyK\poly_K. In 2003, Teleman-Woodward gave a complete list of inequalities for \polyK\poly_K. Their list contains redundant inequalities. In this paper, we describe \polyK\poly_K by a smaller list of inequalities.

Keywords

Cite

@article{arxiv.1310.7331,
  title  = {On the quantum Horn problem},
  author = {Nicolas Ressayre},
  journal= {arXiv preprint arXiv:1310.7331},
  year   = {2013}
}

Comments

Belkale-Kumar obtained independently the results of this paper in arXiv:1310.3191

R2 v1 2026-06-22T01:55:11.035Z