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Non-well-foundedness of well-orderable power sets
Published online by Cambridge University Press: 12 March 2014
Abstract
Tarski [5] showed that for any set X, its set ω(X) of well-orderable subsets has cardinality strictly greater than that of X, even in the absence of the axiom of choice. We construct a Fraenkel-Mostowski model in which there is an infinite strictly descending sequence under the relation ∣ω(X)∣ = ∣Y∣. This contrasts with the corresponding situation for power sets, where use of Hartogs' ℵ-function easily establishes that there can be no infinite descending sequence under the relation .
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- Copyright © Association for Symbolic Logic 2003
References
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