English

Asymptotic distributions of Wishart type products of random matrices

Probability 2020-04-03 v2 Combinatorics Operator Algebras

Abstract

We study asymptotic distributions of large dimensional random matrices of the form BBBB^{*}, where BB is a product of pp rectangular random matrices, using free probability and combinatorics of colored labeled noncrossing partitions. These matrices are taken from the set of off-diagonal blocks of the family Y\mathcal{Y} of independent Hermitian random matrices which are asymptotically free, asymptotically free against the family of deterministic diagonal matrices, and whose norms are uniformly bounded almost surely. This class includes unitarily invariant Hermitian random matrices with limit distributions given by compactly supported probability measures ν\nu on the real line. We express the limit moments in terms of colored labeled noncrossing pair partitions, to which we assign weights depending on even free cumulants of ν\nu and on asymptotic dimensions of blocks (Gaussianization). For products of pp independent blocks, we show that the limit moments are linear combinations of a new family of polynomials called generalized multivariate Fuss-Narayana polynomials. In turn, the product of two blocks of the same matrix leads to an example with rescaled Raney numbers.

Keywords

Cite

@article{arxiv.1612.07041,
  title  = {Asymptotic distributions of Wishart type products of random matrices},
  author = {Romuald Lenczewski and Rafał Sałapata},
  journal= {arXiv preprint arXiv:1612.07041},
  year   = {2020}
}

Comments

32 pages, 7 figures, slightly improved version (Section 2 reformulated, a few errors corrected, one reference added)