**Leo Anthony Harrington** (born May 17, 1946) is a professor of mathematics at the "University of California, Berkeley who works in "recursion theory, "model theory, and "set theory.

- Harrington and "Saharon Shelah showed that the first-order theory of the partially ordered set of recursively enumerable "Turing degrees is undecidable.
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## References[edit]

**^** Paris, J.; Harrington, L. (1977), "A Mathematical Incompleteness in Peano Arithmetic", in "Barwise, J., *Handbook of Mathematical Logic*, North-Holland, pp. 1133–1142
**^** Harrington, L. (1978), "Analytic Determinacy and 0^{#}", *Journal of Symbolic Logic*, **43** (4): 685–693, "JSTOR 2273508, "doi:10.2307/2273508
**^** Harrington, L.; Shelah, S. (1982), "The undecidability of the recursively enumerable degrees", *Bull. Amer. Math. Soc. (N.S.)*, **6** (1): 79–80, "doi:10.1090/S0273-0979-1982-14970-9

## External links[edit]

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