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Weak Injectivity and Congruence Extension in Congruence-Distributive Equational Classes

Published online by Cambridge University Press:  20 November 2018

Brian A. Davey
Brian A. Davey*
Affiliation:
La Trobe University, Bundoora, Victoria, Australia
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Abstract

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There are many concepts which arise naturally in a discussion of injectivity in an equational class; for example, weak injective algebras, absolute subretracts, essential extensions, the congruence extension property, and the amalgamation property (see [3; 9; 17; 18]). It has already been demonstrated in several papers, notably [9; 17; 26; 27; 28], that the study of these concepts is greatly enriched by the assumption that the algebras under consideration have distributive congruence lattices. In this work attention is focused on weak injective algebras (Section 2) and the congruence extension property (Section 3).

Type
Research Article
Information
Canadian Journal of Mathematics , Volume 29 , Issue 3 , 01 June 1977 , pp. 449 - 459
Copyright
Copyright © Canadian Mathematical Society 1977

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