On the time complexity of 2-tag systems and small universal Turing machines

Damien Woods; Turlough Neary

doi:10.1109/focs.2006.58

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arXiv · cs/0612089

On the time complexity of 2-tag systems and small universal Turing machines

Damien Woods·Turlough Neary

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Abstract

We show that 2-tag systems efficiently simulate Turing machines. As a corollary we find that the small universal Turing machines of Rogozhin, Minsky and others simulate Turing machines in polynomial time. This is an exponential improvement on the previously known simulation time overhead and improves a forty year old result in the area of small universal Turing machines.

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Damien Woods, Turlough Neary. 2006-12-19. On the time complexity of 2-tag systems and small universal Turing machines. https://doi.org/10.1109/focs.2006.58

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