English

Distribution of roots of random real generalized polynomials

chao-dyn 2009-10-28 v1 Condensed Matter Chaotic Dynamics

Abstract

The average density of zeros for monic generalized polynomials, Pn(z)=ϕ(z)+k=1nckfk(z)P_n(z)=\phi(z)+\sum_{k=1}^nc_kf_k(z), with real holomorphic ϕ,fk\phi ,f_k and real Gaussian coefficients is expressed in terms of correlation functions of the values of the polynomial and its derivative. We obtain compact expressions for both the regular component (generated by the complex roots) and the singular one (real roots) of the average density of roots. The density of the regular component goes to zero in the vicinity of the real axis like Imz|\hbox{\rm Im}\,z|. We present the low and high disorder asymptotic behaviors. Then we particularize to the large nn limit of the average density of complex roots of monic algebraic polynomials of the form Pn(z)=zn+k=1nckznkP_n(z) = z^n +\sum_{k=1}^{n}c_kz^{n-k} with real independent, identically distributed Gaussian coefficients having zero mean and dispersion δ=1nλ\delta = \frac 1{\sqrt{n\lambda}}. The average density tends to a simple, {\em universal} function of ξ=2nlogz\xi={2n}{\log |z|} and λ\lambda in the domain ξcothξ2nsinarg(z)\xi\coth \frac{\xi}{2}\ll n|\sin \arg (z)| where nearly all the roots are located for large nn.

Keywords

Cite

@article{arxiv.chao-dyn/9606012,
  title  = {Distribution of roots of random real generalized polynomials},
  author = {G. Andrei Mezincescu and Daniel Bessis and Jean-Daniel Fournier and Giorgio Mantica and Francisc D. Aaron},
  journal= {arXiv preprint arXiv:chao-dyn/9606012},
  year   = {2009}
}

Comments

17 pages, Revtex. To appear in J. Stat. Phys. Uuencoded gz-compresed tarfile (.66MB) containing 8 Postscript figures is available by e-mail from [email protected]