The graph expansion of an ordered groupoid
نویسنده
چکیده
We generalise the Margolis-Meakin graph expansion of a group to a construction for ordered groupoids, and show that the graph expansion of an ordered groupoid enjoys structural properties analogous to those for graph expansions of groups. We also use the Cayley graph of an ordered groupoid to prove a version of McAlister’s P–theorem for incompressible ordered groupoids. AMS 2000 Mathematics subject classification: Primary 20L05 Secondary 20M18,20F65
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