Minimal degrees which are $\Sigma _{2}^{0}$ but not $\Delta _{2}^{0}$
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- by Richard A. Shore PDF
- Proc. Amer. Math. Soc. 132 (2004), 563-565 Request permission
Abstract:
We give a short proof of the existence of minimal Turing degrees which are $\Sigma _{2}^{0}$ but not $\Delta _{2}^{0}$.References
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Additional Information
- Richard A. Shore
- Affiliation: Department of Mathematics, Cornell University, Ithaca, New York 14853
- MR Author ID: 161135
- Email: shore@math.cornell.edu
- Received by editor(s): August 19, 2002
- Received by editor(s) in revised form: October 8, 2002
- Published electronically: June 17, 2003
- Additional Notes: This research was partially supported by NSF Grant DMS-0100035
- Communicated by: Carl G. Jockusch, Jr.
- © Copyright 2003 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 132 (2004), 563-565
- MSC (2000): Primary 03D28
- DOI: https://doi.org/10.1090/S0002-9939-03-07080-1
- MathSciNet review: 2022382