The ibT degrees of computably enumerable sets are not dense
نویسندگان
چکیده
We show that the identity bounded Turing degrees of computably enumerable sets are not dense.
منابع مشابه
The computable Lipschitz degrees of computably enumerable sets are not dense
The computable Lipschitz reducibility was introduced by Downey, Hirschfeldt and LaForte under the name of strong weak truthtable reducibility [6]. This reducibility measures both the relative randomness and the relative computational power of real numbers. This paper proves that the computable Lipschitz degrees of computably enumerable sets are not dense. An immediate corollary is that the Solo...
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The strongly bounded Turing reducibilities r = cl (computable Lipschitz reducibility) and r = ibT (identity bounded Turing reducibility) are defined in terms of Turing reductions where the use function is bounded by the identity function up to an additive constant and the identity function, respectively. We show that, for r = ibT, cl, every computably enumerable (c.e.) r-degree a > 0 has the an...
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ورودعنوان ژورنال:
- Ann. Pure Appl. Logic
دوره 141 شماره
صفحات -
تاریخ انتشار 2006