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arXiv · 0910.5070

Crossover Morita equivalences of spin representations of the symmetric and alternating groups

R. Leabovich·M. Schaps
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Abstract

We prove the existence of Morita equivalences between the spin blocks at the extremal points of strings in the block-reduced crystal graph. When the parities of the core partitions are not preserved, these equivalences require crossovers, with a block of the symmtric group Morita equivalent to a block of the alternating group and vice versa. The result permits in improvement of the bound for Donovan's Conjecture given by Kessar.

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R. Leabovich, M. Schaps. 2009-10-27. Crossover Morita equivalences of spin representations of the symmetric and alternating groups. https://arxiv.org/abs/0910.5070

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