arXiv 0905.42092009-05-26math.GR

Low-degree Cohomology of Integral Specht Modules

Christian Weber

备注：: 25 pages
发表信息：: Experimental Mathematics 18 (2009), no. 1, 85-95

英文摘要：

We introduce a way of describing cohomology of the symmetric groups with coefficients in Specht modules over Z or F_p. We study i-th-degree cohomology for i in {0,1,2}. The focus lies on the isomorphism type of second-degree cohomology of integral Specht modules. Unfortunately, only in few cases can we determine this exactly. In many cases we obtain only some information about the prime divisors of the cohomology group's order. The most important tools we use are the Zassenhaus algorithm, the Branching Rules, Bockstein type homomorphisms, and the results from [Burichenko et al., 1996].

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