Verma type modules of level zero for affine Lie algebras
Verma type modules of level zero for affine Lie algebras
We study the structure of Verma type modules of level zero induced from non-standard Borel subalgebras of an affine Kac-Moody algebra. For such modules in “general position” we describe the unique irreducible quotients, construct a BGG type resolution and prove the BGG duality in certain categories. All results are extended …