The linkage principle for restricted critical level representations of affine Kac–Moody algebras
The linkage principle for restricted critical level representations of affine Kac–Moody algebras
We study the restricted category O for an affine Kac--Moody algebra at the critical level. In particular, we prove the first part of the Feigin-Frenkel conjecture: the linkage principle for restricted Verma modules. Moreover, we prove a version of the BGGH-reciprocity principle and we determine the block decomposition of the …