Singular extensions and the second cohomology categorical group
نویسندگان
چکیده
منابع مشابه
Cohomology of Group Extensions
Introduction. Let G be a group, K an invariant subgroup of G. The purpose of this paper is to investigate the relations between the cohomology groups of G, K, and G/K. As in the case of fibre spaces, it turns out that such relations can be expressed by a spectral sequence whose term E2 is HiG/K, HiK)) and whose term Em is the graduated group associated with i7(G). This problem was first studied...
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We shall in fact prove it with C = 2. In the same situation, Aschbacher and Guralnick proved in Theorem A of [1] that \H\G, V)\<\V\. Guralnick has recently improved this bound to \H(G, V)\^\V\l, which is the best possible. At the present time, a proof of the intermediate result \H(G, V)\ «= |V|S is available in preprint form [13]. By using this result, it should be possible with a little extra ...
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ژورنال
عنوان ژورنال: Journal of Homotopy and Related Structures
سال: 2016
ISSN: 2193-8407,1512-2891
DOI: 10.1007/s40062-016-0135-1