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arXiv · 2107.12454

Perfect congruences on bisimple $\omega$-semigroups

Simon M. Goberstein·Katherine Grimshaw·Anthony Kling·Therese Landry·Freda Li
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Abstract

A congruence $\varepsilon$ on a semigroup $S$ is perfect if for any congruence classes $x\varepsilon$ and $y\varepsilon$ their product as subsets of $S$ coincides (as a set) with the congruence class $(xy)\varepsilon$. Perfect congruences on the bicyclic semigroup were found in \cite{key7}. Using the structure of bisimple $\omega$-semigroups determined in \cite{key25} and the description of congruences on these semigroups found in \cite{key20} and \cite{key1}, we obtain a complete characterization of perfect congruences on all bisimple $\omega$-semigroups, substantially generalizing the above mentioned result of \cite{key7}.

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Simon M. Goberstein, Katherine Grimshaw, Anthony Kling, Therese Landry, Freda Li. 2021-07-26. Perfect congruences on bisimple $\omega$-semigroups. https://doi.org/10.1007/s00233-014-9649-1

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