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Changing the heights of automorphism towers by forcing with Souslin trees over L

Published online by Cambridge University Press:  12 March 2014

Gunter Fuchs
Affiliation:
Westfälische Wilhelms-Universität Mùnster, Institut Für Mathematische Logik Und Grundlagenforschung, Einsteinstraβe 62, 48149 Munster., Germany, E-mail: [email protected]
Joel David Hamkins
Affiliation:
Mathematics Program, The Graduate Center of the City University of New York, 365 Fifth Avenue, New York, NY 10016., USA, E-mail: [email protected]

Abstract

We prove that there are groups in the constructible universe whose automorphism towers are highly malleable by forcing. This is a consequence of the fact that, under a suitable diamond hypothesis, there are sufficiently many highly rigid non-isomorphic Souslin trees whose isomorphism relation can be precisely controlled by forcing.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 2008

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References

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