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Characterising subsets of ω1 constructible from a real

Published online by Cambridge University Press:  12 March 2014

P. D. Welch*
Affiliation:
Department of Mathematics, UCLA, Los Angeles, California 90024, E-mail: [email protected]

Abstract

A small large cardinal upper bound in V for proving when certain subsets of ω1 (including the universally Baire subsets) are precisely those constructible from a real is given. In the core model we find an exact equivalence in terms of the length of the mouse order; we show that ∀B ⊆ ω1 [B is universally Baire ⇔ B ϵ L[r] for some real r] is preserved under set-sized forcing extensions if and only if there are arbitrarily large “admissibly measurable” cardinals.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 1994

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References

REFERENCES

[BG]Baumgartner, J. and Galvin, F., Generalized Erdős cardinals and 0#, Annals of Mathematical Logic, vol. 15 (1978), pp. 289313.CrossRefGoogle Scholar
[BJW]Beller, A., Jensen, R. B., and Welch, P. D., Coding the universe, London Mathematical Society Lecture Note Series, no. 47, Cambridge University Press, Cambridge, 1982.CrossRefGoogle Scholar
[CM]Dodd, A. J., The core model, London Mathematical Society Lecture Note Series, no. 61, Cambridge University Press, Cambridge, 1982.CrossRefGoogle Scholar
[DL]Donder, H.-D. and Levinski, J.-P., Some principles related to Chang's conjecture, Annals of Pure and Applied Logic, vol. 45 (1989), pp. 39101.CrossRefGoogle Scholar
[FMW]Feng, Q., Magidor, M., and Woodin, H., Universally Baire sets of reals, Set theory of the continuum (Judah, H.et al., editors), MSRI Publications, no. 26, Springer-Verlag, Berlin, 1992, pp. 203242.CrossRefGoogle Scholar
[K1]Kechris, A. S., Subsets of ℵ1 constructible from a real, Cabal seminar 81–85 (Kechris, A.et al., editors), Lecture Notes in Mathematics, vol. 1333, Springer-Verlag, Berlin, 1987, pp. 110116.CrossRefGoogle Scholar
[K2]Kechris, A. S., Homogeneous trees and projective scales, Cabal seminar 77–79 (Kechris, A. S.et al., editors), Lecture Notes in Mathematics, vol. 839, Springer-Verlag, Berlin, 1981, pp. 3374.CrossRefGoogle Scholar