On the simulation of many storage heads by a single one

Extended abstract
  • Paul M. B. Vitányi
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 154)


Each multitape Turing machine, of which the storage heads scan O(log n) distinct squares in each interval of n steps, for all n ⩾ 1, can be real- time simulated by an oblivious one-head tape unit. There exist multitape Turing machines, e.g. the normal pushdown store, for which the fastest on- line simulation by an oblivious one- head tape unit requires Ω (n √n) time.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1983

Authors and Affiliations

  • Paul M. B. Vitányi
    • 1
  1. 1.Mathematisch CentrumSJ AmsterdamThe Netherlands

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