Hochschild and ordinary cohomology rings of small categories

dc.creatorXu, Fei
dc.date2008-05-21
dc.date2008-07-29
dc.date.accessioned2026-07-07T09:53:06Z
dc.date.available2026-07-07T09:53:06Z
dc.descriptionLet C be a small category and k a field. There are two interesting mathematical subjects: the category algebra kC and the classifying space |C|=BC. We study the ring homomorphism HH*(kC) --> H*(|C|,k) and prove it is split surjective. This generalizes the well-known results for groups and posets. Based on this result, we construct a seven-dimensional category algebra whose Hochschild cohomology ring modulo nilpotents is not finitely generated, against a conjecture of Snashall and Solberg.
dc.descriptionAdvances in Mathematics, to appear
dc.identifierhttps://arxiv.org/abs/0805.3295
dc.identifierhttp://arxiv.org/abs/0805.3295
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/165831
dc.subjectAlgebraic Topology
dc.subjectRings and Algebras
dc.subject18A25, 18A40, 16E30, 16E40
dc.titleHochschild and ordinary cohomology rings of small categories
dc.typetext

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