Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-28T11:04:55.284Z Has data issue: false hasContentIssue false

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

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

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