P ≠ NP ∩ co-NP for Infinite Time Turing Machines
نویسندگان
چکیده
منابع مشابه
0 Ju l 2 00 3 P 6 = NP ∩ co - NP for Infinite Time Turing Machines
Extending results of Schindler [Sch] and Hamkins and Welch [HW03], we establish in the context of infinite time Turing machines that P is properly contained in NP∩ co-NP. Furthermore, NP∩ co-NP is exactly the class of hyperarithmetic sets. For the more general classes, we establish that P = NP ∩ co-NP = NP∩ co-NP, though P is properly contained in NP ∩ co-NP. Within any contiguous block of infi...
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ژورنال
عنوان ژورنال: Journal of Logic and Computation
سال: 2005
ISSN: 1465-363X,0955-792X
DOI: 10.1093/logcom/exi022