Abstract
We present a canonical proof of both the strict and weak Positivstellensatz for rings of differentiable and smooth functions. Our construction is explicit, preserves definability in expansions of the real field, and it works in definably complete expansions of real closed fields as well as for real-valued functions on Banach spaces.
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Acquistapace F., Andradas C., Broglia F.: The Positivstellensatz for definable functions on o-minimal structures. Ill. J. Math. 46(3), 685–693 (2002)
Bochnak, J., Coste, M., Roy, M.-F.: Real algebraic geometry. Translated from the 1987 French original. Revised by the authors. Ergebnisse der Mathematik und ihrer Grenzgebiete (3) [Results in Mathematics and Related Areas (3)], vol. 36. Springer, Berlin, x+430 pp (1998)
Coste, M.: An Introduction to O-minimal Geometry. Dip. Mat. Univ. Pisa. Dottorato di Ricerca in Matematica, Istituti Editoriali e Poligrafici Internazionali, Pisa (2000)
van den Dries, L.: Tame topology and O-minimal structures. LMS Lecture Notes, vol. 248. Cambridge University Press (1998)
Krivine J.L.: Anneau preordones. J. Anal. Math. 12, 307–326 (1964)
Miller C.: Expansions of dense linear orders with the intermediate value property. J. Symb. Logic 66(4), 1783–1790 (2001)
Stengle G.: A nullstellensatz and a positivstellensatz in semialgebraic geometry. Math. Ann. 207, 87–97 (1974)
Schmüdgen K.: The K-moment problem for compact semi-algebraic sets. Math. Ann. 289(2), 203–206 (1991)
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The author has been supported by the Thematic Program on o-minimal Structures and Real Analytic Geometry of the Fields Institute.
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Fischer, A. Positivstellensätze for differentiable functions. Positivity 15, 297–307 (2011). https://doi.org/10.1007/s11117-010-0077-5
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DOI: https://doi.org/10.1007/s11117-010-0077-5