## Notre Dame Journal of Formal Logic

### A New Spectrum of Recursive Models

André Nies

#### Abstract

We describe a strongly minimal theory S in an effective language such that, in the chain of countable models of S, only the second model has a computable presentation. Thus there is a spectrum of an $\omega_{1}^{}$-categorical theory which is neither upward nor downward closed. We also give an upper bound on the complexity of spectra.

#### Article information

Source
Notre Dame J. Formal Logic, Volume 40, Number 3 (1999), 307-314.

Dates
First available in Project Euclid: 28 May 2002

https://projecteuclid.org/euclid.ndjfl/1022615611

Digital Object Identifier
doi:10.1305/ndjfl/1022615611

Mathematical Reviews number (MathSciNet)
MR1845630

Zentralblatt MATH identifier
1007.03036

#### Citation

Nies, André. A New Spectrum of Recursive Models. Notre Dame J. Formal Logic 40 (1999), no. 3, 307--314. doi:10.1305/ndjfl/1022615611. https://projecteuclid.org/euclid.ndjfl/1022615611

#### References

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