Title
Critical points and Gröbner bases: the unmixed case
Abstract
We consider the problem of computing critical points of the restriction of a polynomial map to an algebraic variety. This is of first importance since the global minimum of such a map is reached at a critical point. Thus, these points appear naturally in non-convex polynomial optimization which occurs in a wide range of scientific applications (control theory, chemistry, economics,...). Critical points also play a central role in recent algorithms of effective real algebraic geometry. Experimentally, it has been observed that Gröbner basis algorithms are efficient to compute such points. Therefore, recent software based on the so-called Critical Point Method are built on Gröbner bases engines. Let f1,..., fp be polynomials in Q[x1,...,xn] of degree D, V ⊂ Cn be their complex variety and π1 be the projection map (x1,...,xn) - x1. The critical points of the restriction of π1 to V are defined by the vanishing of f1,...,fp and some maximal minors of the Jacobian matrix associated to f1,...,fp. Such a system is algebraically structured: the ideal it generates is the sum of a determinantal ideal and the ideal generated by f1,...,fp. We provide the first complexity estimates on the computation of Gröbner bases of such systems defining critical points. We prove that under genericity assumptions on f1,...,fp, the complexity is polynomial in the generic number of critical points, i.e. Dp(D - 1)n−p(n-1/p-1). More particularly, in the quadratic case D = 2, the complexity of such a Gröbner basis computation is polynomial in the number of variables n and exponential in p. We also give experimental evidence supporting these theoretical results.
Year
DOI
Venue
2012
10.1145/2442829.2442855
international symposium on symbolic and algebraic computation
Keywords
DocType
Volume
non-convex polynomial optimization,determinantal ideal,degree d,polynomial map,bner base,complexity estimate,bner basis algorithm,bner bases engine,bner basis computation,unmixed case,critical point,polynomial,critical points
Conference
abs/1202.0179
Citations 
PageRank 
References 
12
0.57
19
Authors
3
Name
Order
Citations
PageRank
Jean-Charles Faugère1103774.00
Mohab Safey El Din245035.64
Pierre-Jean Spaenlehauer312912.08