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Uniform versions of some axioms of second order arithmetic

✍ Scribed by Nobuyuki Sakamoto; Takeshi Yamazaki


Publisher
John Wiley and Sons
Year
2004
Tongue
English
Weight
132 KB
Volume
50
Category
Article
ISSN
0044-3050

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✦ Synopsis


Abstract

In this paper, we discuss uniform versions of some axioms of second order arithmetic in the context of higher order arithmetic. We prove that uniform versions of weak weak KΓΆnig's lemma WWKL and Ξ£^0^~1~ separation are equivalent to (βˆƒ^2^) over a suitable base theory of higher order arithmetic, where (βˆƒ^2^) is the assertion that there exists Ξ¦^2^ such that Ξ¦__f__^1^ = 0 if and only if βˆƒx^0^(fx = 0) for all f. We also prove that uniform versions of some well‐known theorems are equivalent to (βˆƒ^2^) or the axiom (Suslin) of the existence of the Suslin operator. (Β© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)


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