Two-row nilpotent orbits of cyclic quivers

الأصل · EN

We prove that the local intersection cohomology of nilpotent orbit closures of cyclic quivers is trivial when the two orbits involved correspond to partitions with at most two rows. This gives a geometric proof of a result of Graham and Lehrer, which states that standard modules of the affine Hecke algebra of GLd corresponding to nilpotents with at most two Jordan blocks are multiplicity-free.