## The canonical Ramsey theorem and computability theory

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- by Joseph R. Mileti PDF
- Trans. Amer. Math. Soc.
**360**(2008), 1309-1340 Request permission

## Abstract:

Using the tools of computability theory and reverse mathematics, we study the complexity of two partition theorems, the Canonical Ramsey Theorem of Erdös and Rado, and the Regressive Function Theorem of Kanamori and McAloon. Our main aim is to analyze the complexity of the solutions to computable instances of these problems in terms of the Turing degrees and the arithmetical hierarchy. We succeed in giving a sharp characterization for the Canonical Ramsey Theorem for exponent 2 and for the Regressive Function Theorem for all exponents. These results rely heavily on a new, purely inductive, proof of the Canonical Ramsey Theorem. This study also unearths some interesting relationships between these two partition theorems, Ramsey’s Theorem, and König’s Lemma.## References

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## Additional Information

**Joseph R. Mileti**- Affiliation: Department of Mathematics, University of Illinois, 1409 W. Green Street, Urbana, Illinois 61801
- Address at time of publication: Department of Mathematics, University of Chicago, 5734 S. University Ave., Chicago, Illinois 60637
- Email: mileti@math.uchicago.edu
- Received by editor(s): August 29, 2005
- Published electronically: October 23, 2007
- Additional Notes: Most of the results in this paper appear in the author’s dissertation written at the University of Illinois at Urbana-Champaign under the direction of Carl Jockusch with partial financial support provided by NSF Grant DMS-9983160.
- © Copyright 2007
American Mathematical Society

The copyright for this article reverts to public domain 28 years after publication. - Journal: Trans. Amer. Math. Soc.
**360**(2008), 1309-1340 - MSC (2000): Primary 03D80, 05D10
- DOI: https://doi.org/10.1090/S0002-9947-07-04390-5
- MathSciNet review: 2357697