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arXiv · 2512.09881

An Ehresmann-Schein-Nambooripad-type theorem for left restriction semigroupoids

Rafael Haag·Wesley G. Lautenschlaeger·Thaísa Tamusiunas
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Abstract

We introduce the concept of locally inductive constellations and establish isomorphisms between the categories of left restriction semigroupoids and locally inductive constellations. This construction offers an alternative to the celebrated Ehresmann-Schein-Nambooripad (ESN) Theorem and, in particular, generalizes results for one-sided restriction semigroups. We also obtain ESN-type theorems for one-sided restriction categories and inverse semigroupoids.

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Rafael Haag, Wesley G. Lautenschlaeger, Thaísa Tamusiunas. 2025-12-10. An Ehresmann-Schein-Nambooripad-type theorem for left restriction semigroupoids. https://arxiv.org/abs/2512.09881

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