Countability of id-jump traceable reals

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A real is an element of 2ω2^{\omega}. For an order function hh, a real xx is hh-jump traceable if, for every Turing functional Φ\Phi, there is an hh-bounded computably enumerable trace (Un)n∈N(U_n)_{n\in\mathbb{N}} such that, whenever Φx\Phi^x is total, Φx(n)∈Un\Phi^x(n)\in U_n for almost every nn. The statement concerns id-jump traceable reals, namely the case of the identity order function.

Countability conjecture. There are only countably many id-jump traceable reals.

The surrounding discussion proves instead that, for every positive rational ϵ\epsilon, there are 2ℵ02^{\aleph_0} many n1+ϵn^{1+\epsilon}-jump traceable reals. The status of the asserted countability claim is not resolved in the supplied text.

References

Primary source

André Nies, “Logic Blog 2011”, arXiv:1403.5721 (2014).

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