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The Beth-closure of (Qα) is not finitely generated

Published online by Cambridge University Press:  12 March 2014

Lauri Hella
Affiliation:
Department of Mathematics, University of Helsinki, 00100 Helsinki, Finland, E-mail: hella@cc.helsinki.fi
Kerkko Luosto
Affiliation:
Department of Mathematics, University of Helsinki, 00100 Helsinki, Finland, E-maii: kluosto@cc.helsinki.fi

Abstract

We prove that if ℵα is uncountable and regular, then the Beth-closure of ωω(Qα) is not a sublogic of αω(Qn), where Qn is the class of all n-ary generalized quantifiers. In particular, B(ωω(Qα)) is not a sublogic of any finitely generated logic; i.e., there does not exist a finite set Q of Lindström quantifiers such that B(ωω(Qα)) ≤ ωω(Q).

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 1992

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References

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