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arXiv · 0804.4702

Extending the Ehresmann-Schein-Nambooripad Theorem

Christopher Hollings
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Abstract

We extend the `join-premorphisms' part of the Ehresmann-Schein-Nambooripad Theorem to the case of two-sided restriction semigroups and inductive categories, following on from a result of Lawson (1991) for the `morphisms' part. However, it is so-called `meet-premorphisms' which have proved useful in recent years in the study of partial actions. We therefore obtain an Ehresmann-Schein-Nambooripad-type theorem for meet-premorphisms in the case of two-sided restriction semigroups and inductive categories. As a corollary, we obtain such a theorem in the inverse case.

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Christopher Hollings. 2009-02-22. Extending the Ehresmann-Schein-Nambooripad Theorem. https://doi.org/10.1007/s00233-010-9215-4

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