Powered by OpenAIRE graph
Found an issue? Give us feedback
image/svg+xml Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao Closed Access logo, derived from PLoS Open Access logo. This version with transparent background. http://commons.wikimedia.org/wiki/File:Closed_Access_logo_transparent.svg Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao Semigroup Forumarrow_drop_down
image/svg+xml Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao Closed Access logo, derived from PLoS Open Access logo. This version with transparent background. http://commons.wikimedia.org/wiki/File:Closed_Access_logo_transparent.svg Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao
Semigroup Forum
Article . 1995 . Peer-reviewed
License: Springer TDM
Data sources: Crossref
image/svg+xml Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao Closed Access logo, derived from PLoS Open Access logo. This version with transparent background. http://commons.wikimedia.org/wiki/File:Closed_Access_logo_transparent.svg Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao
zbMATH Open
Article . 1995
Data sources: zbMATH Open
versions View all 2 versions
addClaim

E-free objects and e-locality for completely regular semigroups

\(E\)-free objects and \(E\)-locality for completely regular semigroups
Authors: Jones, P.R.;

E-free objects and e-locality for completely regular semigroups

Abstract

Let \(H\) be a variety of groups and let \(CR(H)\) denote the class of all completely regular semigroups all of whose subgroups belong to \(H\). This class is a variety of unary semigroups and forms an existence variety (e- variety), as well. The main result of the paper states that the e-variety \(CR(H)\) is e-local: each regular semigroupoid \(C\) (i.e. for each edge \(x\) there is an edge \(y\) such that \(x=xyx\)) all of whose local semigroups \(C_c\) belong to \(CR(H)\) divides a member of \(CR(H)\) in a ``regular'' way. Locality of varieties and pseudovarieties of monoids (and semigroups) has been introduced and discussed systematically by \textit{B. Tilson} [J. Pure Appl. Algebra 48, 83-198 (1987; Zbl 0627.20031)] and has been shown to be an indispensable tool for the study of semidirect product decompositions of varieties and pseudovarieties. The present paper deals with the rightful analogue of this concept in the context of regular semigroups and e-varieties, and the result will have important applications in the theory of semidirect product decompositions of e-varieties [see, e.g., \textit{P. R. Jones} and \textit{P. G. Trotter}, Semidirect products of regular semigroups, Trans. Am. Math. Soc. (to appear), and forthcoming papers]. The proof of the main result relies heavily on some knowledge of the bifree semigroup in \(CR(H)\) (termed ``e-free'' object in this paper), and more generally, of the bifree semigroupoid on a graph \(X\) in the e- variety \(lCR(H)\) of all regular semigroupoids whose local semigroups belong to \(CR(H)\). This knowledge, a word problem solution, is obtained as a preliminary result. Finally, it is pointed out that in all stages finiteness may be preserved so that the result is equally important in the context of finite (regular) semigroups, that is, in the context of (e-) pseudovarieties.

Country
Germany
Related Organizations
Keywords

word problem, completely regular semigroups, Free semigroups, generators and relations, word problems, semidirect product decompositions, bifree semigroups, pseudovarieties of monoids, Regular semigroups, Article, Varieties and pseudovarieties of semigroups, variety of unary semigroups, 510.mathematics, variety of groups, e-variety, existence variety, Quasivarieties, local semigroups

  • BIP!
    Impact byBIP!
    selected citations
    These citations are derived from selected sources.
    This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
    3
    popularity
    This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.
    Average
    influence
    This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
    Average
    impulse
    This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.
    Average
Powered by OpenAIRE graph
Found an issue? Give us feedback
selected citations
These citations are derived from selected sources.
This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Citations provided by BIP!
popularity
This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.
BIP!Popularity provided by BIP!
influence
This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Influence provided by BIP!
impulse
This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.
BIP!Impulse provided by BIP!
3
Average
Average
Average
Green