Normal Functors and Strong Protomodularitydominique
نویسنده
چکیده
The notion of normal subobject having an intrinsic meaning in any proto-modular category, we introduce the notion of normal functor, namely left exact conservative functor which reeects normal subobjects. The point is that for the category Gp of groups the change of base functors, with respect to the bration of pointed objects, are not only conservative (this is the deenition of a protomodular category), but also normal. This leads to the notion of strongly protomodular category. Some of their properties are given, the main one being that this notion is inherited by the slice categories.
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