Abstract
The restricted category \(\mathcal {O}\) at the critical level over an affine Kac–Moody algebra is a certain subcategory of the ordinary BGG-category \(\mathcal {O}\). We study a deformed version introduced by Arakawa and Fiebig and calculate the center of the deformed restricted category \(\mathcal {O}\). This complements a result of Fiebig which describes the center of the non-restricted category \(\mathcal {O}\) outside the critical hyperplanes over a symmetrizable Kac–Moody algebra.
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I would like to thank my supervisor Peter Fiebig for many inspiring discussions.
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Supported by the DFG priority program 1388.
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Kübel, J. Centers for the restricted category \(\mathcal {O}\) at the critical level over affine Kac–Moody algebras. Math. Z. 276, 1133–1149 (2014). https://doi.org/10.1007/s00209-013-1237-7
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DOI: https://doi.org/10.1007/s00209-013-1237-7