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arXiv · 1901.05731

A Tale of Two Categories: Inductive groupoids and Cross-connections

P. A. Azeef Muhammed·Mikhail V. Volkov
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Abstract

A groupoid is a small category in which all morphisms are isomorphisms. An inductive groupoid is a specialised groupoid whose object set is a regular biordered set and the morphisms admit a partial order. A normal category is a specialised small category whose object set is a strict preorder and the morphisms admit a factorisation property. A pair of `related' normal categories constitutes a cross-connection. Both inductive groupoids and cross-connections were identified by Nambooripad \cite{mem,cross} as categorical models of regular semigroups. We explore the inter-relationship between these seemingly different categorical structures and prove a direct category equivalence between the category of inductive groupoids and the category of cross-connections.

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P. A. Azeef Muhammed, Mikhail V. Volkov. 2019-01-17. A Tale of Two Categories: Inductive groupoids and Cross-connections. https://arxiv.org/abs/1901.05731

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