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arXiv · 2610.16059

Baire measurable functions and automorphisms of the truth-table degrees

Bjørn Kjos-Hanssen
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Abstract

We show that if an automorphism $π$ of the truth-table degrees is induced by a Baire measurable function $F\colon 2^ω\to 2^ω$, or merely induced on some comeager set by a continuous function, then $π$ is the identity. The same results hold for the weak truth-table degrees. The argument is an adaptation to truth-table reducibility of OpenAI's recent proof that the Turing degrees are rigid.

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Bjørn Kjos-Hanssen. 2026-10-12. Baire measurable functions and automorphisms of the truth-table degrees. https://arxiv.org/abs/2610.16059

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