Skip to main content
Log in

On the separation of basic semialgebraic sets by polynomials

  • Published:
manuscripta mathematica Aims and scope Submit manuscript

Abstract

In this paper we show that two disjoint basic closed semialgebraic sets, defined over a real closed field R, can be separated by a polynomial, if one of them has dimension ≦2. Counterexamples are given in all higher dimensions.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Becker, E., Bröcker, L.: On the description of the reduced Wittring. J. of Algebra 52 (2), 328–346 (1972)

    Article  Google Scholar 

  2. Rochnak, J., Coste, M., Roy, M.-F.: Géométric algébrique réelle. Springer, Ergebnisse 1987

    Google Scholar 

  3. Bröcker, L.: Zur Theorie der quadratischen Formen über formal reellen Körpern. Math. Ann. 210, 233–256 (1974)

    Google Scholar 

  4. Bröcker, L.: Über die Anzahl der Anordnungen eines kommutativen Körpers. Arch. Math. 29, 458–463 (1977)

    Article  Google Scholar 

  5. Bröcker, L.: Minimale Erzeugung von Positivbereichen. Geometriae Dedicata 16, 335–350 (1984)

    Article  Google Scholar 

  6. Bröcker, L.: Spaces of orderings and semialgebraic sets. Can. Math. Soc. Conference Proceedings. Vol. 4, 231–247 (1984)

    Google Scholar 

  7. Lam, T.-Y.: Orderings, valuations and quadratic forms. A.M.S. conference board of the mathematical sciences 52 (1983)

  8. Marshall, M.: Classification of finite spaces of orderings. Can. J. Math. 31, 320–330 (1979)

    Google Scholar 

  9. Marshall, M.: Quotients and inverse limits of spaces of orderings. Can. J. Math. 31, 604–616 (1979)

    Google Scholar 

  10. Marshall, M.: The Witt ring of a space of orderings. Trans. Amer. math. sce. 258, 505–521 (1980)

    Google Scholar 

  11. Marshall, M.: Spaces of orderings IV. Can. J. Math. 32, 603–627 (1980)

    Google Scholar 

  12. Marshall, M.: Spaces of orderings: Systems of quadratic forms, local structure, and saturation. Communications in Algebra 12 (6), 723–743 (1984)

    Google Scholar 

  13. Schwartz, N.: Local stability and saturation in spaces of orderings. Can. J. Math. 25 (3), 454–477 (1983)

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Bröcker, L. On the separation of basic semialgebraic sets by polynomials. Manuscripta Math 60, 497–508 (1988). https://doi.org/10.1007/BF01258667

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF01258667

Keywords

Navigation