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Difference randomness. (English) Zbl 1214.03029
In the paper under review, the authors introduce a new randomness notion called difference randomness. They prove the following results: 5mm
(1)
A real is difference random if and only if it is a Martin-Löf random real and Turing incomplete if and only if no difference martingale succeeds on it.
(2)
A recursively enumerable set $$A$$ is a base for difference randomness if and only if it is Martin-Löf coverable;
(3)
Lowness for difference randomness is equivalent to non-weak-Martin-Löf cuppability.
Reviewer: Liang Yu (Nanjing)

##### MSC:
 03D32 Algorithmic randomness and dimension
##### Keywords:
difference randomness; Martin-Löf randomness
Full Text:
##### References:
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