On the power of real-time turing machines under varying specifications

  • Paul M. B. Vitányi
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 85)


We investigate the relative computing power of Turing machines with differences in the number of work tapes, heads pro work tape, instruction repertoire etc. We concentrate on the k-tape, k-head and k-head jump models as well as the 2-way multihead finite automata with and without jumps. Differences in computing power between machines of unlike specifications emerge under the real-time restriction. In particular it is shown that k+1 heads are more powerful than k heads for real-time Turing machines.


Turing Machine Finite Automaton Closure Property Input Tape Marked Concatenation 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1980

Authors and Affiliations

  • Paul M. B. Vitányi
    • 1
  1. 1.Mathematisch CentrumAmsterdamThe Netherlands

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