English

Exponential moments for disk counting statistics at the hard edge of random normal matrices

Mathematical Physics 2023-07-28 v2 math.MP Probability

Abstract

We consider the multivariate moment generating function of the disk counting statistics of a model Mittag-Leffler ensemble in the presence of a hard wall. Let nn be the number of points. We focus on two regimes: (a) the ``hard edge regime" where all disk boundaries are at a distance of order 1n\frac{1}{n} from the hard wall, and (b) the ``semi-hard edge regime" where all disk boundaries are at a distance of order 1n\frac{1}{\sqrt{n}} from the hard wall. As n+n \to + \infty, we prove that the moment generating function enjoys asymptotics of the form \begin{align*} & \exp \bigg(C_{1}n + C_{2}\ln n + C_{3} + \frac{C_{4}}{\sqrt{n}} + \mathcal{O}(n^{-\frac{3}{5}})\bigg), & & \mbox{for the hard edge}, \\ & \exp \bigg(C_{1}n + C_{2}\sqrt{n} \hspace{0.12cm} + C_{3} + \frac{C_{4}}{\sqrt{n}} + \mathcal{O}\bigg(\frac{(\ln n)^{4}}{n}\bigg)\bigg), & & \mbox{for the semi-hard edge}. \end{align*} In both cases, we determine the constants C1,,C4C_{1},\dots,C_{4} explicitly. We also derive precise asymptotic formulas for all joint cumulants of the disk counting function, and establish several central limit theorems. Surprisingly, and in contrast to the ``bulk", ``soft edge" and ``semi-hard edge" regimes, the second and higher order cumulants of the disk counting function in the ``hard edge" regime are proportional to nn and not to n\sqrt{n}.

Keywords

Cite

@article{arxiv.2207.11092,
  title  = {Exponential moments for disk counting statistics at the hard edge of random normal matrices},
  author = {Yacin Ameur and Christophe Charlier and Joakim Cronvall and Jonatan Lenells},
  journal= {arXiv preprint arXiv:2207.11092},
  year   = {2023}
}

Comments

41 pages, 2 figures