On delineability of varieties in CAD-based quantifier elimination with two equational constraints

Let <i>V</i> ⊂ R<sup><i>r</i></sup> denote the real algebraic variety defined by the conjunction <i>f</i> = 0 ∧ <i>g</i> = 0, where <i>f</i> and <i>g</i> are real polynomials in the variables <i>x</i><sub>1</sub>, ..., <i>x</i><sub><i>r</i></sub> and let <i>S</i> be a submanifold of R<sup><i>r</i>-2</sup>. This paper proposes the notion of the <i>analytic delineability of V on S with respect to the last 2 variables</i>. It is suggested that such a notion could be useful in solving more efficiently certain quantifier elimination problems which contain the conjunction <i>f</i> = 0 ⊂ <i>g</i> = 0 as subformula, using a variation of the CAD-based method. Two bi-equational lifting theorems are proved which provide the basis for such a method.

[1]  George E. Collins,et al.  Hauptvortrag: Quantifier elimination for real closed fields by cylindrical algebraic decomposition , 1975, Automata Theory and Formal Languages.

[2]  Scott McCallum,et al.  On projection in CAD-based quantifier elimination with equational constraint , 1999, ISSAC '99.

[3]  B. F. Caviness,et al.  Quantifier Elimination and Cylindrical Algebraic Decomposition , 2004, Texts and Monographs in Symbolic Computation.

[4]  Scott McCallum,et al.  An Improved Projection Operation for Cylindrical Algebraic Decomposition of Three-Dimensional Space , 1988, J. Symb. Comput..

[5]  B. Mourrain,et al.  Resultant over the residual of a complete intersection , 2001 .

[6]  Wolfgang Krull Funktionaldeterminanten und Diskriminanten bei Polynomen in mehreren Unbestimmten. II , 1939 .

[7]  Christopher W. Brown,et al.  On using bi-equational constraints in CAD construction , 2005, ISSAC.

[8]  Christopher W. Brown QEPCAD B: a program for computing with semi-algebraic sets using CADs , 2003, SIGS.

[9]  Wolfgang Krull Funktionaldeterminanten und Diskriminanten bei Polynomen in mehreren Unbestimmten , 1939 .

[10]  Scott McCallum,et al.  An Improved Projection Operation for Cylindrical Algebraic Decomposition , 1985, European Conference on Computer Algebra.

[11]  C. Hoffmann Algebraic curves , 1988 .

[12]  George E. Collins,et al.  Partial Cylindrical Algebraic Decomposition for Quantifier Elimination , 1991, J. Symb. Comput..

[13]  Scott McCallum,et al.  Factors of iterated resultants and discriminants , 1997, SIGS.

[14]  Wilfred Kaplan,et al.  Introduction to analytic functions , 1969 .

[15]  Hoon Hong,et al.  Simple solution formula construction in cylindrical algebraic decomposition based quantifier elimination , 1992, ISSAC '92.

[16]  G. E. Collins,et al.  Quantifier Elimination by Cylindrical Algebraic Decomposition — Twenty Years of Progress , 1998 .

[17]  Hans J. Stetter,et al.  Numerical polynomial algebra , 2004 .

[18]  Christopher W. Brown Guaranteed solution formula construction , 1999, ISSAC '99.

[19]  Scott McCallum An improved projection operation for cylindrical algebraic decomposition (computer algebra, geometry, algorithms) , 1984 .

[20]  M. Marden Geometry of Polynomials , 1970 .

[21]  Scott McCallum On propagation of equational constraints in CAD-based quantifier elimination , 2001, ISSAC '01.

[22]  Bernard Mourrain,et al.  Explicit factors of some iterated resultants and discriminants , 2006, Math. Comput..

[23]  George E. Collins Application of Quantifier Elimination to Solotareff’s Approximation Problem , 1996 .

[24]  David A. Cox,et al.  Ideals, Varieties, and Algorithms , 1997 .

[25]  Daniel Lazard,et al.  Iterated discriminants , 2009, J. Symb. Comput..

[26]  Christopher W. Brown Improved Projection for Cylindrical Algebraic Decomposition , 2001, J. Symb. Comput..

[27]  George E. Collins,et al.  Cylindrical Algebraic Decomposition I: The Basic Algorithm , 1984, SIAM J. Comput..

[28]  David A. Cox,et al.  Ideals, Varieties, and Algorithms: An Introduction to Computational Algebraic Geometry and Commutative Algebra, 3/e (Undergraduate Texts in Mathematics) , 2007 .