The proof-theoretic analysis of transfinitely iterated quasi least fixed points
نویسندگان
چکیده
منابع مشابه
The proof-theoretic analysis of transfinitely iterated quasi least fixed points
The starting point of this article is an old question asked by Feferman in his paper on Hancock’s conjecture [6] about the strength of ID1. This theory is obtained from the well-known theory ID1 by restricting fixed point induction to formulas that contain fixed point constants only positively. The techniques used to perform the proof-theoretic analysis of ID1 also permit to analyze its transfi...
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Progressions of iterated reflection principles can be used as a tool for ordinal analysis of formal systems. Technically, in some sense, they replace the use of omega-rule. We compare the information obtained by this kind of analysis with the results obtained by the more usual proof-theoretic techniques. In some cases the techniques of iterated reflection principles allows to obtain sharper res...
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ژورنال
عنوان ژورنال: Journal of Symbolic Logic
سال: 2006
ISSN: 0022-4812,1943-5886
DOI: 10.2178/jsl/1154698573