(1) School of Mathematics, University of Wales, Bangor Dean Street, Bangor, Gwynedd, LL57 1UT, United Kingdom;(2) School of Mathematics, University of Wales, Bangor Dean Street, Bangor, Gwynedd, LL57 1UT, United Kingdom
Abstract:
McAlister proved that a necessary and sufficient condition for a regular semigroup S to be locally inverse is that it can be embedded as a quasi-ideal in a semigroup T which satisfies the following two conditions: (1) T = TeT, for some idempotent e; and (2) eTe is inverse. We generalise this result to the class of semigroups with local units in which all local submonoids have commuting idempotents.