Space Complexity in Infinite Time Turing Machines
نویسندگان
چکیده
منابع مشابه
Space Bounds for Infinitary Computation
Infinite Time Turing Machines (or Hamkins-Kidder machines) have been introduced in [HaLe00] and their computability theory has been investigated in comparison to the usual computability theory in a sequence of papers by Hamkins, Lewis, Welch and Seabold: [HaLe00], [We00a], [We00b], [HaSe01], [HaLe02], [We04], [We05] (cf. also the survey papers [Ha02], [Ha04] and [Ha05]). Infinite Time Turing Ma...
متن کاملIs P = PSPACE for Infinite Time Turing Machines?
question P ? = NP for Infinite Time Turing Machines, and several variants on it, are treated in e.g. [Sc], [DeHaSc], and [HaWe]. Besides time complexity, we may also try to look at issues of space complexity in ITTMs. However, because an ITTM contains tapes of length ω, and all nontrivial ITTM computations will use the entire, ω-length tape, simply measuring the space complexity by counting the...
متن کاملRelativistic Computers and Non-uniform Complexity Theory
Recent research in theoretical physics on ‘Malament-Hogarth space-times’ indicates that so-called relativistic computers can be conceived that can carry out certain classically undecidable queries in finite time. We observe that the relativistic Turing machines which model these computations recognize precisely theΔ2−sets of the Arithmetical Hierarchy. In a complexity-theoretic analysis, we sho...
متن کاملDeterministic one-way Turing machines with sublinear space bounds
Deterministic one-way Turing machines with sublinear space bounds are systematically studied. We distinguish among the notions of strong, weak, and restricted space bounds. The latter is motivated by the study of P automata. The space available on the work tape depends on the number of input symbols read so far, instead of the entire input. The class of functions space constructible by such mac...
متن کاملOrdinal Computability
Ordinal computability uses ordinals instead of natural numbers in abstract machines like register or Turing machines. We give an overview of the computational strengths of α-β-machines, where α and β bound the time axis and the space axis of some machine model. The spectrum ranges from classical Turing computability to ∞-∞-computability which corresponds to Gödel’s model of constructible sets. ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2007