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Cauchy completeness in elementary logic

Published online by Cambridge University Press:  12 March 2014

J. C. Cifuentes
Affiliation:
Department of Mathematics, University of Campinas, Caixa Postal 6065, 13081-970 Campinas, SP, Brazil
A. M. Sette
Affiliation:
Department of Mathematics, University of Campinas, Caixa Postal 6065, 13081-970 Campinas, SP, Brazil
D. Mundici
Affiliation:
Department of Computer Science, University of Milan, Via Comelico 39-41, 20135 Milan, Italy, E-mail: [email protected]

Abstract

The inverse of the distance between two structures of finite type τ is naturally measured by the smallest integer q such that a sentence of quantifier rank q − 1 is satisfied by but not by . In this way the space Strτ of structures of type τ is equipped with a pseudometric. The induced topology coincides with the elementary topology of Strτ. Using the rudiments of the theory of uniform spaces, in this elementary note we prove the convergence of every Cauchy net of structures, for any type τ.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 1996

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References

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