Decompositions of some Specht modules I

Stephen Donkin; Haralampos Geranios

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arXiv · 1810.10275

Decompositions of some Specht modules I

Stephen Donkin·Haralampos Geranios

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Abstract

We give a decomposition as a direct sum of indecomposable modules of several types of Specht modules in characteristic $2$. These include the Specht modules labelled by hooks, whose decomposability was considered by Murphy. Since the main arguments are essentially no more difficult for Hecke algebras at parameter $q=-1$, we proceed in this level of generality.

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Stephen Donkin, Haralampos Geranios. 2018-10-24. Decompositions of some Specht modules I. https://arxiv.org/abs/1810.10275

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