English

Natural boundary and zero distribution of random polynomials in smooth domains

Probability 2017-10-04 v1 Complex Variables

Abstract

We consider the zero distribution of random polynomials of the form Pn(z)=k=0nakBk(z)P_n(z) = \sum_{k=0}^n a_k B_k(z), where {ak}k=0\{a_k\}_{k=0}^{\infty} are non-trivial i.i.d. complex random variables with mean 00 and finite variance. Polynomials {Bk}k=0\{B_k\}_{k=0}^{\infty} are selected from a standard basis such as Szeg\H{o}, Bergman, or Faber polynomials associated with a Jordan domain GG whose boundary is C2,αC^{2, \alpha} smooth. We show that the zero counting measures of PnP_n converge almost surely to the equilibrium measure on the boundary of GG. We also show that if {ak}k=0\{a_k\}_{k=0}^{\infty} are i.i.d. random variables, and the domain GG has analytic boundary, then for a random series of the form f(z)=k=0akBk(z),f(z) =\sum_{k=0}^{\infty}a_k B_k(z), G\partial{G} is almost surely a natural boundary for f(z).f(z).

Keywords

Cite

@article{arxiv.1710.00937,
  title  = {Natural boundary and zero distribution of random polynomials in smooth domains},
  author = {Igor Pritsker and Koushik Ramachandran},
  journal= {arXiv preprint arXiv:1710.00937},
  year   = {2017}
}

Comments

9 pages