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Cohomology in singular blocks of parabolic category $\mathcal{O}$

Published online by Cambridge University Press:  15 May 2023

Jonathan Gruber*
Affiliation:
Department of Mathematics, National University of Singapore, Singapore, Singapore

Abstract

We determine the dimensions of $\textrm{Ext}$-groups between simple modules and dual generalized Verma modules in singular blocks of parabolic versions of category $\mathcal{O}$ for complex semisimple Lie algebras and affine Kac-Moody algebras.

Type
Research Article
Copyright
© The Author(s), 2023. Published by Cambridge University Press on behalf of Glasgow Mathematical Journal Trust

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