کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
437434 690140 2011 17 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Splitting and nonsplitting in the enumeration degrees
موضوعات مرتبط
مهندسی و علوم پایه مهندسی کامپیوتر نظریه محاسباتی و ریاضیات
پیش نمایش صفحه اول مقاله
Splitting and nonsplitting in the  enumeration degrees
چکیده انگلیسی

This paper continues the project, initiated in (Arslanov, Cooper and Kalimullin 2003) [3], of describing general conditions under which relative splittings are derivable in the local structure of the enumeration degrees, for which the Ershov hierarchy provides an informative setting.The main results below include a proof that any high total e-degree below is splittable over any low e-degree below it, a non-cupping result in the high enumeration degrees which occurs at a low level of the Ershov hierarchy, and a 0̸‴-priority construction of a e-degree unsplittable over a 3-c.e. e-degree below it.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Theoretical Computer Science - Volume 412, Issue 18, 15 April 2011, Pages 1669-1685