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arXiv · 1910.13735

Projective Covers of 2-star-permutable Categories

Vasileios Aravantinos-Sotiropoulos
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Abstract

We introduce the notion of star-symmetry for relations in a multi-pointed category and use it to obtain a characterization of the projective covers of 2-star-permutable categories. This generalizes the results of Rosický-Vitale for regular Mal'tsev categories, as well as those of Gran-Rodelo for regular subtractive categories. We apply the characterization in terms of star-symmetry to recover the syntactic conditions defining E-subtractive varieties in the sense of Ursini.

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Vasileios Aravantinos-Sotiropoulos. 2019-10-30. Projective Covers of 2-star-permutable Categories. https://arxiv.org/abs/1910.13735

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