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Relational structures determined by their finite induced substructures

Published online by Cambridge University Press:  12 March 2014

I. M. Hodkinson
Affiliation:
School of Mathematical Sciences, Queen Mary College, London EL 4NS, England
H. D. Macpherson*
Affiliation:
New Hall, Cambridge CB3 ODF, England
*
Mathematical Institute, 24–29 St. Giles, Oxford OX1 3LB, England

Abstract

A countably infinite relational structure M is called absolutely ubiquitous if the following holds: whenever N is a countably infinite structure, and M and N have the same isomorphism types of finite induced substructures, there is an isomorphism from M to N. Here a characterisation is given of absolutely ubiquitous structures over languages with finitely many relation symbols. A corresponding result is proved for uncountable structures.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 1988

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References

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