A jump inversion theorem for the enumeration jump
نویسنده
چکیده
We prove a jump inversion theorem for the enumeration jump and a minimal pair type theorem for the enumeration reducibilty. As an application some results of Selman, Case and Ash are obtained.
منابع مشابه
The Jump Operator on the Ω-enumeration Degrees
The jump operator on the ω-enumeration degrees is introduced in [11]. In the present paper we prove a jump inversion theorem which allows us to show that the enumeration degrees are first order definable in the structureDω ′ of the ω-enumeration degrees augmented by the jump operator. Further on we show that the groups of the automorphisms of Dω ′ and of the enumeration degrees are isomorphic. ...
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ورودعنوان ژورنال:
- Arch. Math. Log.
دوره 39 شماره
صفحات -
تاریخ انتشار 2000