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An Epi-Reflector for Universal Theories

Published online by Cambridge University Press:  20 November 2018

Paul D. Bacsich
Paul D. Bacsich*
Affiliation:
Open University, Bletchley, Buckinghamshire U.K.
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A construction of an epi-reflector by injective hull techniques is given which applies to the class of models of any universal theory with the Amalgamation Property and there yields a weak but functorial type of algebraic closure. Various completions such as the boolean envelope and quotient field constructions are identified as such injective hulls over epimorphic injections. Forms of the Amalgamation Property are also shown to eliminate various pathologies of epimorphisms and equalizers.

Type
Research Article
Information
Canadian Mathematical Bulletin , Volume 16 , Issue 2 , June 1973 , pp. 167 - 171
Copyright
Copyright © Canadian Mathematical Society 1973

References

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