There’s no forcing a least upper bound
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- by Robert S. Lubarsky PDF
- Proc. Amer. Math. Soc. 105 (1989), 998-1002 Request permission
Abstract:
While it is possible to have an increasing $\omega$-sequence of $c$-degrees with a least upper bound in a particular model of ZF, we show that it is not possible to force a sequence with a least upper bound absolute among all generic extensions of the original modelReferences
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Additional Information
- © Copyright 1989 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 105 (1989), 998-1002
- MSC: Primary 03E40; Secondary 03E45
- DOI: https://doi.org/10.1090/S0002-9939-1989-0943796-8
- MathSciNet review: 943796