PROTOLOCALISATIONS OF EXACT MAL’CEV CATEGORIES To Walter Tholen, on his sixtieth birthday
نویسندگان
چکیده
A protolocalisation of a regular category is a full reflective regular subcategory, whose reflection preserves pullbacks of regular epimorphisms along arbitrary morphisms. We devote special attention to the epireflective protolocalisations of an exact Mal’cev category; we characterise them in terms of a corresponding closure operator on equivalence relations. We give some examples in algebra and in topos theory.
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