Free Objects in Certain Varieties of Inverse Semigroups

@inproceedings{Margolis2010FreeOI,
title={Free Objects in Certain Varieties of Inverse Semigroups},
author={Stuart W. Margolis and John C. Meakin and John Buchan Stephen},
year={2010}
}

In this paper it is shown how the graphical methods developed by Stephen for analyzing inverse semigroup presentations may be used to study varieties of inverse semigroups. In particular, these methods may be used to solve the word problem for the free objects in the variety of inverse semigroups generated by the five-element combinatorial Brandt semigroup and in the variety of inverse semigroups determined by laws of the form x = x. Covering space methods are used to study the free objects in… CONTINUE READING