کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4662152 1633529 2008 15 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Continuity of capping in
موضوعات مرتبط
مهندسی و علوم پایه ریاضیات منطق ریاضی
پیش نمایش صفحه اول مقاله
Continuity of capping in
چکیده انگلیسی

A set A⊆ω is called computably enumerable (c.e., for short), if there is an algorithm to enumerate the elements of it. For sets A,B⊆ω, we say that A is bounded Turing reducible to (or alternatively, weakly truth table (wtt, for short) reducible to) B if there is a Turing functional, Φ say, with a computable bound of oracle query bits such that A is computed by Φ equipped with an oracle B, written . Let be the structure of the c.e. bT-degrees, the c.e. degrees under the bounded Turing reductions. In this paper we study the continuity properties in . We show that for any c.e. bT-degree , there is a c.e. bT-degree such that for any c.e. bT-degree , if and only if . We prove that the analog of the Seetapun local noncappability theorem from the c.e. Turing degrees also holds in . This theorem demonstrates that every is noncappable with any nontrivial degree below some (i.e. if and then ).

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Annals of Pure and Applied Logic - Volume 155, Issue 1, August 2008, Pages 1-15