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Isomorphism of Computable Structures and Vaught's Conjecture

Published online by Cambridge University Press:  12 March 2014

Howard Becker*
Affiliation:
PMB 128, 4840 Forest Dr., Ste. 6–B, Columbia, SC 29206-4810, USA, E-mail: hsbecker@hotmail.com

Abstract

The following question is open: Does there exist a hyperarithmetic class of computable structures with exactly one non-hyperarithmetic isomorphism-type? Given any oracle α ∈ 2ω, we can ask the same question relativized to α. A negative answer for every α implies Vaught's Conjecture for Lω1ω.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 2013

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