Algebra in superextensions of groups, II: cancelativity and centers

Given a countable group X we study the algebraic structure of its
 superextension λ(X). This is a right-topological semigroup consisting of all maximal linked systems on X endowed with the operation 
 
 A∘B={C⊂X:{x∈X:x−1C∈B}∈A} 
 
 that extends the grou...

Full description

Saved in:
Bibliographic Details
Published in:Algebra and Discrete Mathematics
Date:2008
ISSN:1726-3255
Main Authors: Banakh, T., Gavrylkiv, V.
Format: Article
Language:English
Published: Інститут прикладної математики і механіки НАН України 2008
Online Access:https://nasplib.isofts.kiev.ua/handle/123456789/153356
Tags: Add Tag
No Tags, Be the first to tag this record!
Journal Title:Digital Library of Periodicals of National Academy of Sciences of Ukraine
Cite this:Algebra in superextensions of groups, II: cancelativity and centers / T. Banakh, V. Gavrylkiv // Algebra and Discrete Mathematics. — 2008. — Vol. 7, № 4. — С. 1–14. — Бібліогр.: 10 назв. — англ.

Institution

Digital Library of Periodicals of National Academy of Sciences of Ukraine
_version_ 1862737067271782400
author Banakh, T.
Gavrylkiv, V.
author_facet Banakh, T.
Gavrylkiv, V.
citation_txt Algebra in superextensions of groups, II: cancelativity and centers / T. Banakh, V. Gavrylkiv // Algebra and Discrete Mathematics. — 2008. — Vol. 7, № 4. — С. 1–14. — Бібліогр.: 10 назв. — англ.
collection DSpace DC
container_title Algebra and Discrete Mathematics
description Given a countable group X we study the algebraic structure of its
 superextension λ(X). This is a right-topological semigroup consisting of all maximal linked systems on X endowed with the operation 
 
 A∘B={C⊂X:{x∈X:x−1C∈B}∈A} 
 
 that extends the group operation of X. We show that the subsemigroup λ∘(X) of free maximal linked systems contains an open dense subset of right cancelable elements. Also we prove that the topological center of λ(X) coincides with the subsemigroup λ∙(X) of all maximal linked systems with finite support. This result is applied to show that the algebraic center of λ(X) coincides with the algebraic center of X provided X is countably infinite. On the other hand, for finite groups X of order 3≤|X|≤5 the algebraic center of λ(X) is strictly larger than the algebraic center of X.
first_indexed 2025-12-07T19:57:24Z
format Article
fulltext
id nasplib_isofts_kiev_ua-123456789-153356
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
issn 1726-3255
language English
last_indexed 2025-12-07T19:57:24Z
publishDate 2008
publisher Інститут прикладної математики і механіки НАН України
record_format dspace
spelling Banakh, T.
Gavrylkiv, V.
2019-06-14T03:34:04Z
2019-06-14T03:34:04Z
2008
Algebra in superextensions of groups, II: cancelativity and centers / T. Banakh, V. Gavrylkiv // Algebra and Discrete Mathematics. — 2008. — Vol. 7, № 4. — С. 1–14. — Бібліогр.: 10 назв. — англ.
1726-3255
2000 Mathematics Subject Classification: 20M99, 54B20.
https://nasplib.isofts.kiev.ua/handle/123456789/153356
Given a countable group X we study the algebraic structure of its
 superextension λ(X). This is a right-topological semigroup consisting of all maximal linked systems on X endowed with the operation 
 
 A∘B={C⊂X:{x∈X:x−1C∈B}∈A} 
 
 that extends the group operation of X. We show that the subsemigroup λ∘(X) of free maximal linked systems contains an open dense subset of right cancelable elements. Also we prove that the topological center of λ(X) coincides with the subsemigroup λ∙(X) of all maximal linked systems with finite support. This result is applied to show that the algebraic center of λ(X) coincides with the algebraic center of X provided X is countably infinite. On the other hand, for finite groups X of order 3≤|X|≤5 the algebraic center of λ(X) is strictly larger than the algebraic center of X.
en
Інститут прикладної математики і механіки НАН України
Algebra and Discrete Mathematics
Algebra in superextensions of groups, II: cancelativity and centers
Article
published earlier
spellingShingle Algebra in superextensions of groups, II: cancelativity and centers
Banakh, T.
Gavrylkiv, V.
title Algebra in superextensions of groups, II: cancelativity and centers
title_full Algebra in superextensions of groups, II: cancelativity and centers
title_fullStr Algebra in superextensions of groups, II: cancelativity and centers
title_full_unstemmed Algebra in superextensions of groups, II: cancelativity and centers
title_short Algebra in superextensions of groups, II: cancelativity and centers
title_sort algebra in superextensions of groups, ii: cancelativity and centers
url https://nasplib.isofts.kiev.ua/handle/123456789/153356
work_keys_str_mv AT banakht algebrainsuperextensionsofgroupsiicancelativityandcenters
AT gavrylkivv algebrainsuperextensionsofgroupsiicancelativityandcenters