UC 2011: Unconventional Computation pp 201-211 | Cite as

Computation with Narrow CTCs

  • A. C. Cem Say
  • Abuzer Yakaryılmaz
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6714)

Abstract

We examine some variants of computation with closed timelike curves (CTCs), where various restrictions are imposed on the memory of the computer, and the information carrying capacity and range of the CTC. We give full characterizations of the classes of languages recognized by polynomial time probabilistic and quantum computers that can send a single classical bit to their own past. Such narrow CTCs are demonstrated to add the power of limited nondeterminism to deterministic computers, and lead to exponential speedup in constant-space probabilistic and quantum computation.

Keywords

Stationary Distribution Core Model Regular Language Input String Language Recognition 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • A. C. Cem Say
    • 1
  • Abuzer Yakaryılmaz
    • 1
  1. 1.Department of Computer EngineeringBoğaziçi UniversityBebekTurkey

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