Totally categorical structures
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- by Ehud Hrushovski PDF
- Trans. Amer. Math. Soc. 313 (1989), 131-159 Request permission
Abstract:
A first order theory is totally categorical if it has exactly one model in each infinite power. We prove here that every such theory admits a finite language, and is finitely axiomatizable in that language, modulo axioms stating that the structure is infinite. This was conjectured by Vaught. We also show that every ${\aleph _0}$-stable, ${\aleph _0}$-categorical structure is a reduct of one that has finitely many models in small uncountable powers. In the case of structures of disintegrated type we nearly find an explicit structure theorem, and show that the remaining obstacle resides in certain nilpotent automorphism groups.References
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Additional Information
- © Copyright 1989 American Mathematical Society
- Journal: Trans. Amer. Math. Soc. 313 (1989), 131-159
- MSC: Primary 03C45; Secondary 03C35
- DOI: https://doi.org/10.1090/S0002-9947-1989-0943605-1
- MathSciNet review: 943605