Abstract
We characterize those varieties of universal algebras where every split epimorphism considered as a map of sets is a product projection. In addition we obtain new characterizations of semi-abelian, protomodular, unital and subtractive varieties as well as varieties of right Ω-loops and biternary systems.
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N. Martins-Ferreira’s research was supported by IPLeiria(ESTG/CDRSP) and FCT grant SFRH/BPD/43216/2008. Also by the FCT projects: PTDC/EME-CRO/120585/2010, PTDC/MAT/120222/2010 and PEst-OE/EME/UI4044/2013.
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Gray, J.R.A., Martins-Ferreira, N. On Algebraic and More General Categories Whose Split Epimorphisms Have Underlying Product Projections. Appl Categor Struct 23, 429–446 (2015). https://doi.org/10.1007/s10485-013-9336-5
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DOI: https://doi.org/10.1007/s10485-013-9336-5
Keywords
- Split extensions
- split epimorphisms
- algebraic theories
- right omega-loops
- semi-abelian
- protomodular
- unital
- subtractive