Non-Turing Computers and Non-Turing Computability
نویسندگان
چکیده
منابع مشابه
Non-Turing Computers and Non-Turing Computability*
Various examples of Malament-Hogarth (hereafter, M-H) spacetimes are given in Hogarth (1992), but the following artificial example from Earman and Norton (1993) is perhaps the simplest. Start with Minkowski spacetime (R4, η) and choose a scalar field Ω on M such that Ω=1 outside a compact set C⊂M and Ω tends rapidly to infinity as a point r∈C is approached. The spacetime (R4-r, Ω2η), depicted i...
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[Turing then gives his formal definitions and in particular says that for a real number or function on the natural numbers to be computable it must be computable by amachine that gives an output for every input.] No attempt has yet been made to show that the "computable" numbers include all numbers which would naturally be regarded as computable. All arguments which can be given are bound to be...
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ژورنال
عنوان ژورنال: PSA: Proceedings of the Biennial Meeting of the Philosophy of Science Association
سال: 1994
ISSN: 0270-8647
DOI: 10.1086/psaprocbienmeetp.1994.1.193018