Degree spectra of the successor relation of computable linear orderings
نویسندگان
چکیده
We establish that for every computably enumerable (c.e.) Turing degree b, the upper cone of c.e. Turing degrees determined by b is the degree spectrum of the successor relation of some computable linear ordering. This follows from our main result, that for a large class of linear orderings, the degree spectrum of the successor relation is closed upward in the c.e. Turing degrees.
منابع مشابه
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ورودعنوان ژورنال:
- Arch. Math. Log.
دوره 48 شماره
صفحات -
تاریخ انتشار 2009