Hostname: page-component-586b7cd67f-g8jcs Total loading time: 0 Render date: 2024-11-24T18:23:52.009Z Has data issue: false hasContentIssue false

T-convexity and tame extensions

Published online by Cambridge University Press:  12 March 2014

Adam H. Lewenberg
Affiliation:
Department of Mathematics, University of Illinois, Urbana, Illinois 61820, E-mail: [email protected]

Abstract

Let T be a complete o-minimal extension of the theory of real closed fields. We characterize the convex hulls of elementary substructures of models of T and show that the residue field of such a convex hull has a natural expansion to a model of T. We give a quantifier elimination relative to T for the theory of pairs (ℛ, V) where ℛ ⊨ T and V ≠ ℛ is the convex hull of an elementary substructure of ℛ. We deduce that the theory of such pairs is complete and weakly o-minimal. We also give a quantifier elimination relative to T for the theory of pairs with ℛ a model of T and a proper elementary substructure that is Dedekind complete in ℛ. We deduce that the theory of such “tame” pairs is complete.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 1995

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[Bi]Bianconi, Ricardo, Model completeness results for elliptic and abelian functions, Annals of Pure and Applied Logic, vol. 54 (1991), pp. 121136.CrossRefGoogle Scholar
[B1]Bröcker, Ludwig, On the reductions of semialgebraic sets by real valuations, Recent advances in real algebraic geometry and quadratic forms (Jacob, W. B., Lam, T.-Y., and Robson, R. O., editors), Contemporary Mathematics, vol. 155, 1994, pp. 7595.CrossRefGoogle Scholar
[B2]Bröcker, Ludwig, Families of semialgebraic sets and limits, Real algebraic geometry, proceedings (Rennes, 1991) (Coste, M., et al, editors), Lecture Notes in Mathematics no. 1524, Springer-Verlag, Berlin, 1992, pp. 145162.CrossRefGoogle Scholar
[C-D]Cherlin, Gregory and Dickmann, Max A., Real closed rings. II: Model theory, Annals of Pure and Applied Logic, vol. 25 (1983), pp. 213231.CrossRefGoogle Scholar
[D-vdD]Denef, J. and van den Dries, L., p-adic and real subanalytic sets, Annals of Mathematics, ser. 2, vol. 128 (1988), pp. 79138.CrossRefGoogle Scholar
[vdD1]van den Dries, Lou, Algebraic theories with definable Skolem functions, this Journal, vol. 49 (1984), pp. 625629.Google Scholar
[vdD2]van den Dries, Lou, A generalization of the Tarski-Seidenberg theorem, and some nondefinability results, Bulletin (New Series) of the American Mathematical Society, vol. 15 (1986), pp. 189193.CrossRefGoogle Scholar
[vdD3]van den Dries, Lou, On the elementary theory of restricted elementary functions, this Journal, vol. 53 (1988), pp. 796808.Google Scholar
[vdD4]van den Dries, Lou, Limits of definable families, in preparation.Google Scholar
[vdD-M-M]van den Dries, Lou, Macintyre, Angus, and Marker, David, The elementary theory of restricted analytic fields with exponentiation, Annals of Mathematics, vol. 85 (1994), pp. 1956.Google Scholar
[vdD-Mi]van den Dries, Lou and Miller, Chris, On the real exponential field with restricted analytic functions, Israel Journal of Mathematics, vol. 85 (1994), pp. 1956.CrossRefGoogle Scholar
[K-P-S]Knight, Julia F., Pillay, Anand, and Steinhorn, Charles, Definable sets in ordered structures, II, Transactions of the American Mathematical Society, vol. 295 (1986), pp. 593605.CrossRefGoogle Scholar
[Ma]Macintyre, Angus, Classifying pairs of real closed fields, Ph.D. thesis, Stanford University, Stanford, California, 1968.Google Scholar
[M-S]Marker, David and Steinhorn, Charles, Definable types in o-minimal theories, this Journal, vol. 59 (1994), pp. 185198.Google Scholar
[M-M-S]Mcpherson, Dugald, Marker, David, and Steinhorn, Charles, Weakly o-minimal theories, in preparation.Google Scholar
[Mi1]Miller, Chris, Exponentiation is hard to avoid, Proceedings of the American Mathematical Society (to appear).Google Scholar
[Mi2]Miller, Chris, Expansions of the real field with power functions, Annals of Pure and Applied Logic, vol. 68 (1994), pp. 7994.CrossRefGoogle Scholar
[P]Pillay, Anand, Definability of types and pairs of o-minimal structures, this Journal (to appear).Google Scholar
[P-S]Pillay, Anand and Steinhorn, Charles, Definable sets in ordered structures. I, Transactions of the American Mathematical Society, vol. 295 (1986), pp. 565592.CrossRefGoogle Scholar
[P-S2]Pillay, Anand and Steinhorn, Charles, On Dedekind complete O-minimal structures, this Journal, vol. 52 (1987), pp. 156164.Google Scholar
[Pr]Prestel, Alexander, Einführung in die Mathematische Logik und Modelltheorie, Friedr. Vieweg & Sohn, Braunschweig/Wiesbaden, 1986.CrossRefGoogle Scholar
[W]Wilkie, A. J., as yet untitled, Journal of the American Mathematical Society (to appear).Google Scholar