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Model Theory of Epimorphisms

Published online by Cambridge University Press:  20 November 2018

Paul D. Bacsich
Paul D. Bacsich*
Affiliation:
Mathematical Institute, Oxford
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Given a first-order theory T, welet be the category of models of T and homomorphisms between them. We shall show that a morphism A→B of is an epimorphism if and only if every element of B is definable from elements of A in a certain precise manner (see Theorem 1), and from this derive the best possible Cowell- power Theorem for .

Type
Research Article
Information
Canadian Mathematical Bulletin , Volume 17 , Issue 4 , 01 December 1974 , pp. 471 - 477
Copyright
Copyright © Canadian Mathematical Society 1974

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