Resolutions, Relation Modules and Schur Multipliers for Categories
نویسندگان
چکیده
We show that the construction in group cohomology of the Gruenberg resolution associated to a free presentation and the resulting relation module can be copied in the context of representations of categories. We establish five-term exact sequences in the cohomology of categories and go on to show that the Schur multiplier of the category has properties which generalize those of the Schur multiplier of a group. To the memory of Karl Gruenberg.
منابع مشابه
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