In 1970, M. Gerstenhaber introduced a list of axioms defining Moore categories in order to develop the Baer Extension Theory. In this paper, we study some implications between the axioms and compare them with more recent notions, showing that, apart from size restrictions, a Moore category is a pointed, strongly protomodular and Barr-exact category with cokernels.
Keywords: short exact sequence, normal object, protomodular category, strongly protomodular category, Barr-exact category, Moore category
2000 MSC: 18E10,18A30
Theory and Applications of Categories,
Vol. 12, 2004,
No. 6, pp 237-247.
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