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arXiv · 2210.02269

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

Jonathan Gruber
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Abstract

We determine the dimensions of $\mathrm{Ext}$-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.

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Jonathan Gruber. 2022-10-05. Cohomology in singular blocks of parabolic category $\mathcal{O}$. https://arxiv.org/abs/2210.02269

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