English

High Probability Analysis of the Condition Number of Sparse Polynomial Systems

Numerical Analysis 2025-10-20 v1 Numerical Analysis Algebraic Geometry

Abstract

Let F:=(f_1,...,f_n) be a random polynomial system with fixed n-tuple of supports. Our main result is an upper bound on the probability that the condition number of f in a region U is larger than 1/epsilon. The bound depends on an integral of a differential form on a toric manifold and admits a simple explicit upper bound when the Newton polytopes (and underlying covariances) are all identical. We also consider polynomials with real coefficients and give bounds for the expected number of real roots and (restricted) condition number. Using a Kahler geometric framework throughout, we also express the expected number of roots of f inside a region U as the integral over U of a certain {\bf mixed volume} form, thus recovering the classical mixed volume when U = (C^*)^n.

Keywords

Cite

@article{arxiv.math/0212179,
  title  = {High Probability Analysis of the Condition Number of Sparse Polynomial Systems},
  author = {Gregorio Malajovich and J. Maurice Rojas},
  journal= {arXiv preprint arXiv:math/0212179},
  year   = {2025}
}

Comments

29 pages, no figures. Extensive revision and streamlining of math.NA/0012104. In particular, new theorem with explicit high probability estimate of the condition number of a random sparse polynomial system (Theorem 1) has been added