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Extension and amalgamation in rings

Published online by Cambridge University Press:  14 November 2011

J. Renshaw
Affiliation:
Department of Pure Mathematics, University of St Andrews, St Andrews, Fife KY16 9SS, Scotland

Synopsis

It is proved that if a ring R has the extension property in containing ringSi, then the amalgam [R; Si,] is strongly embeddable. Using a result of P. M. Cohn, a necessary and sufficient condition for a ring to be an amalgamation base is then given. It is also shown that R is a level subring of a ring S if and only if S/R is flat. From this, a classical result of P. M. Cohn on flat amalgams is proved.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1986

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