Detalhes do Documento

On difunctionality of class relations

Autor(es): Hoefnagel, Michael ; Janelidze, Zurab ; Rodelo, Diana

Data: 2020

Identificador Persistente: http://hdl.handle.net/10400.1/16538

Origem: Sapientia - Universidade do Algarve

Assunto(s): Class relations; Congruence permutability; Congruence distributivity; Congruence modularity; Directly decomposable congruence classes; Difunctionality; Egg-box property; Mal'tsev condition; Mal'tsev variety; Shifting lemma; Class relations; Class relations; Congruence permutability; Congruence permutability; Congruence distributivity; Congruence distributivity; Congruence modularity; Congruence modularity; Directly decomposable congruence classes; Directly decomposable congruence classes; Difunctionality; Difunctionality; Egg-box property; Egg-box property; Mal'tsev condition; Mal'tsev condition; Mal'tsev variety; Mal'tsev variety; Shifting lemma; Shifting lemma


Descrição

For a given variety V of algebras, we define a class relation to be a binary relation R subset of S(2)which is of the form R = S-2 boolean AND K for some congruence class K on A(2), where A is an algebra in V such that S subset of A. In this paper we study the following property of V : every reflexive class relation is an equivalence relation. In particular, we obtain equivalent characterizations of this property analogous to well-known equivalent characterizations of congruence-permutable varieties. This property determines a Mal'tsev condition on the variety and in a suitable sense, it is a join of Chajda's egg-box property as well as Duda's direct decomposability of congruence classes.

Tipo de Documento Artigo científico
Idioma Inglês
Contribuidor(es) Sapientia
Licença CC
facebook logo  linkedin logo  twitter logo 
mendeley logo

Documentos Relacionados