A basis result for sets of reals with an application to minimal covers
Authors:
Leo A. Harrington and Alexander S. Kechris
Journal:
Proc. Amer. Math. Soc. 53 (1975), 445-448
MSC:
Primary 02K30; Secondary 02F30, 04A15
DOI:
https://doi.org/10.1090/S0002-9939-1975-0398832-7
MathSciNet review:
0398832
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Abstract | References | Similar Articles | Additional Information
Abstract: It is shown that every set of reals which contains reals of arbitrarily high Turing degree in the hyperarithmetic hierarchy contains reals of every Turing degree above the degree of Kleene's
. As an application it is shown that every Turing degree above the Turing degree of Kleene's
is a minimal cover.
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Additional Information
DOI:
https://doi.org/10.1090/S0002-9939-1975-0398832-7
Article copyright:
© Copyright 1975
American Mathematical Society