Higher Randomness and Forcing with Closed Sets
نویسندگان
چکیده
منابع مشابه
Algorithmic Randomness of Closed Sets
We investigate notions of randomness in the space C[2N] of nonempty closed subsets of {0, 1}N. A probability measure is given and a version of the Martin-Löf test for randomness is defined. Π2 random closed sets exist but there are no random Π1 closed sets. It is shown that any random closed set is perfect, has measure 0, and has box dimension log2 4 3 . A random closed set has no n-c.e. elemen...
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ژورنال
عنوان ژورنال: Theory of Computing Systems
سال: 2016
ISSN: 1432-4350,1433-0490
DOI: 10.1007/s00224-016-9681-5