James’s Conjecture holds for weight four blocks of Iwahori–Hecke algebras
نویسنده
چکیده
James’s Conjecture suggests that in certain cases, the decomposition numbers for the Iwahori– Hecke algebra of the symmetric group over a field of prime characteristic (and in particular, the decomposition numbers for the symmetric group itself) coincide with the decomposition numbers for a corresponding Iwahori–Hecke algebra defined over C, and hence can be computed using the LLT algorithm. We prove this conjecture for blocks of weight 4.
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