Characterizing Lowness for Demuth Randomness
نویسندگان
چکیده
We show the existence of noncomputable oracles which are low for Demuth randomness, answering a question in [14] (also Problem 5.5.19 in [33]). We fully characterize lowness for Demuth randomness using an appropriate notion of traceability. Central to this characterization is a partial relativization of Demuth randomness, which may be more natural than the fully relativized version. We also show that an oracle is low for weak Demuth randomness if and only if it is computable.
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ورودعنوان ژورنال:
- J. Symb. Log.
دوره 79 شماره
صفحات -
تاریخ انتشار 2014