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.
Citation
André Nies. "A New Spectrum of Recursive Models." Notre Dame J. Formal Logic 40 (3) 307 - 314, Summer 1999. https://doi.org/10.1305/ndjfl/1022615611
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