Semilatice Decompositions of Semigroups. Hereditariness and Periodicity—An Overview

Abstract

A semigroup is an algebraic structure consisting of a set with an associative binary operation defined on it. We can say that most of the work within theory is done on semigroups with a finiteness condition, i.e. a semigroups possessing any property which is valid for all finite semigroups—like, for example, completely \(\pi \)-regularity, periodicity are. There are many different techniques for describing various kinds of semigroups. Among the methods with general applications is a semilattice decomposition of semigroups. Here, we are interested, in particular, in the decomposability of a certain type of semigroups with finiteness conditions into a semilattice of archimedean semigroups. Having in mind that the definition of finiteness condition may be given, also, in terms of elements of the semigroup, its subsemigroups, in terms of ideals or congruences of certain types, we choose to characterize them mostly by making connections between their elements and/or their special subsets. We are, also, going to list some of the applications of presented classes of semigroups and their semilattice decompositions in certain types of ring constructions. This overview, which is, by no mean, comprehensive one, is mainly based on the results presented in the book [27], and articles [8, 28, 29].