## Notre Dame Journal of Formal Logic

### A Nonstandard Counterpart of WWKL

#### Abstract

In this paper, we introduce a system of nonstandard second-order arithmetic $\mathsf{ns}$-$\mathsf{WWKL_0}$ which consists of $\mathsf{ns}$-$\mathsf{BASIC}$ plus Loeb measure property. Then we show that $\mathsf{ns}$-$\mathsf{WWKL_0}$ is a conservative extension of $\mathsf{WWKL_0}$ and we do Reverse Mathematics for this system.

#### Article information

Source
Notre Dame J. Formal Logic, Volume 52, Number 3 (2011), 229-243.

Dates
First available in Project Euclid: 28 July 2011

https://projecteuclid.org/euclid.ndjfl/1311875771

Digital Object Identifier
doi:10.1215/00294527-1435429

Mathematical Reviews number (MathSciNet)
MR2822486

Zentralblatt MATH identifier
1250.03118

#### Citation

Simpson, Stephen G.; Yokoyama, Keita. A Nonstandard Counterpart of WWKL. Notre Dame J. Formal Logic 52 (2011), no. 3, 229--243. doi:10.1215/00294527-1435429. https://projecteuclid.org/euclid.ndjfl/1311875771

#### References

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