### A New Spectrum of Recursive Models

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

#### 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 -categorical theory which is neither upward nor downward closed. We also give an upper bound on the complexity of spectra.

First Page:
Primary Subjects: 03D45
Secondary Subjects: 03C57
Full-text: Open access

Permanent link to this document: http://projecteuclid.org/euclid.ndjfl/1022615611
Mathematical Reviews number (MathSciNet): MR1845630
Digital Object Identifier: doi:10.1305/ndjfl/1022615611
Zentralblatt MATH identifier: 1007.03036

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Project Euclid: euclid.ndjfl/1039724885
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