English

Bounds on the number of real solutions to polynomial equations

Algebraic Geometry 2007-10-04 v2

Abstract

We use Gale duality for polynomial complete intersections and adapt the proof of the fewnomial bound for positive solutions to obtain the bound (e^4+3) 2^(k choose 2) n^k/4 for the number of non-zero real solutions to a system of n polynomials in n variables having n+k+1 monomials whose exponent vectors generate a subgroup of Z^n of odd index. This bound exceeds the bound for positive solutions only by the constant factor (e^4+3)/(e^2+3) and it is asymptotically sharp for k fixed and n large.

Keywords

Cite

@article{arxiv.0706.4134,
  title  = {Bounds on the number of real solutions to polynomial equations},
  author = {Daniel J. Bates and Frédéric Bihan and Frank Sottile},
  journal= {arXiv preprint arXiv:0706.4134},
  year   = {2007}
}

Comments

5 pages