论文信息 - The Possible Turing Degree of the Nonzero Member in a Two Element Degree Spectrum

The Possible Turing Degree of the Nonzero Member in a Two Element Degree Spectrum

Abstract We construct a recursive model A , a recursive subset R of its domain, and a (nonzero) Turing degree x ⩽ 00 satisfying the following condition. The nonrecursive images of R under all isomorphisms from A to other recursive models are of Turing degree x and cannot be recursively enumerable.

Valentina S. Harizanov

[1] Valentina S. Harizanov. Some Effects of Ash-Nerode and Other Decidability Conditions on Degree Spectra , 1991, Ann. Pure Appl. Log..

[2] Christopher J. Ash. Stability of recursive structures in arithmetical degrees , 1986, Ann. Pure Appl. Log..

[3] Valentina S. Harizanov. Uncountable Degree Spectra , 1991, Ann. Pure Appl. Log..

[4] S. S. Goncharov. Computable single-valued numerations , 1980 .

[5] S. S. Goncharov,et al. Problem of the number of non-self-equivalent constructivizations , 1980 .