# Space-Bounded Quantum Complexity

@article{Watrous1999SpaceBoundedQC,
title={Space-Bounded Quantum Complexity},
author={John Watrous},
journal={J. Comput. Syst. Sci.},
year={1999},
volume={59},
pages={281-326}
}
• J. Watrous
• Published 1999
• Computer Science
• J. Comput. Syst. Sci.
This paper investigates the computational power of space-bounded quantum Turing machines. The following facts are proved for space-constructible space bounds s satisfying s(n)=?(logn): 1.Any quantum Turing machine (QTM) running in space s can be simulated by an unbounded error probabilistic Turing machine (PTM) run- ning in space O(s). No assumptions on the probability of error or running time for the QTM are required, although it is assumed that all transition amplitudes of the QTM are… Expand
67 Citations
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