Bourn, Dominique; Gran, Marino Centrality and connectors in Maltsev categories. (English) Zbl 1061.18006 Algebra Univers. 48, No. 3, 309-331 (2002). A category \(\mathcal C\) is Maltsev if any reflexive relation in \(\mathcal C\) is an equivalence. The authors define two basic concepts: centrality of equivalence relations and a connector between two binary relations. Applying these concepts, they develop a new approach to the classical property of centrality of equivalence relations. The internal concept of connector allows them to clarify classical results on Maltsev varieties and to extend them to the more general context of regular Maltsev categories. It is proved that Maltsev categories can be characterized in terms of a property of connectors. Reviewer: Ivan Chajda (Olomouc) Cited in 2 ReviewsCited in 32 Documents MSC: 18C05 Equational categories 08C15 Quasivarieties 08B05 Equational logic, Mal’tsev conditions 18E10 Abelian categories, Grothendieck categories Keywords:Maltsev categories; centrality of equivalence relations; connector; internal groupoids PDFBibTeX XMLCite \textit{D. Bourn} and \textit{M. Gran}, Algebra Univers. 48, No. 3, 309--331 (2002; Zbl 1061.18006) Full Text: DOI