A continuous and rational solution to Hilbert’s 17th problem and several cases of the Positivstellensatz

  • Charles N. Delzell
  • Laureano González-Vega
  • Henri Lombardi
Part of the Progress in Mathematics book series (PM, volume 109)


From the Positivstellensatz we construct a continuous and rational solution for Hilbert’s 17th problem and for several cases of the Positivstellensatz. The solutions are obtained using an especially simple method.


Rational Solution Intuitionistic Logic Finiteness Theorem Algebraic Identity Real Algebraic Geometry 
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Copyright information

© Birkhäuser Boston 1993

Authors and Affiliations

  • Charles N. Delzell
    • 1
  • Laureano González-Vega
    • 2
  • Henri Lombardi
    • 3
  1. 1.Dept. MathematicsLouisiana State UniversityBaton RougeUSA
  2. 2.Dept. MatemáticasUniversidad de CantabriaSantanderSpain
  3. 3.Lab. de MathématiquesUniversité de Franche-ComtéBesançonFrance

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