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arXiv · 0812.3334

On the restricted Verma modules at the critical level

Tomoyuki Arakawa·Peter Fiebig
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Abstract

We study the restricted Verma modules of an affine Kac-Moody algebra at the critical level with special emphasis on their Jordan-H"older multiplicities. The Feigin-Frenkel conjecture gives a formula for these multiplicities that involves the periodic Kazhdan-Lusztig polynomials. We prove this conjecture for all subgeneric blocks and for the case of anti-dominant simple subquotients.

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Tomoyuki Arakawa, Peter Fiebig. 2010-09-20. On the restricted Verma modules at the critical level. https://arxiv.org/abs/0812.3334

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