Combinatorial construction of Gelfand-Tsetlin modules for
arXiv:1611.07908
Abstract
We propose a new effective method of constructing explicitly Gelfand -Tsetlin modules for . We obtain a large family of simple modules that have a basis consisting of Gelfand-Tsetlin tableaux, the action of the Lie algebra is given by the Gelfand-Tsetlin formulas and with all Gelfand-Tsetlin multiplicities equal . As an application of our construction we prove necessary and sufficient condition for the Gelfand and Graev's continuation construction to define a module which was conjectured by Lemire and Patera.