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arXiv · 2610.11969

Non-recursive trade-offs for two-way machines

Christos Kapoutsis
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Abstract

If the machines of some type A have enough resources to (i) solve problems that no machine of type B can solve, and (ii) simulate any unary two-way deterministic finite automaton that has access to a linearly-bounded counter, then typically no recursive function can upper bound the increase in the size of description when a machine of type A is replaced by an equivalent machine of type B.

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Christos Kapoutsis. 2026-10-08. Non-recursive trade-offs for two-way machines. https://arxiv.org/abs/2610.11969

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