Abstract
In this paper we prove that every nonzero \(\Delta^0_2\) e-degree is cuppable to 0 e ′ by a 1-generic \(\Delta^0_2\) e-degree (so low and nontotal) and that every nonzero ω-c.e. e-degree is cuppable to 0 e ′ by an incomplete 3-c.e. e-degree.
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Soskova, M.I., Wu, G. (2007). Cupping \(\Delta_2^0\) Enumeration Degrees to 0 e ′. In: Cooper, S.B., Löwe, B., Sorbi, A. (eds) Computation and Logic in the Real World. CiE 2007. Lecture Notes in Computer Science, vol 4497. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-73001-9_77
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DOI: https://doi.org/10.1007/978-3-540-73001-9_77
Publisher Name: Springer, Berlin, Heidelberg
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