English

Operator-valued Khintchine inequality for $\epsilon$-free semicircles

Functional Analysis 2025-10-23 v2 Operator Algebras

Abstract

We exhibit several bounds for operator norms of the sum of ϵ\epsilon-free semicircular random variables introduced in the paper of Speicher and Wysocza\'{n}ski. In particular, using the first and second largest eigenvalues of the adjacency matrix ϵ\epsilon, we show analogs of the operator-valued Khintchine-type inequality obtained by Haagerup and Pisier.

Keywords

Cite

@article{arxiv.2503.10558,
  title  = {Operator-valued Khintchine inequality for $\epsilon$-free semicircles},
  author = {Benoît Collins and Akihiro Miyagawa},
  journal= {arXiv preprint arXiv:2503.10558},
  year   = {2025}
}

Comments

12 pages and 1 figure. We added new bounds. This version has been accepted for publication with the Bulletin of the London Mathematical Society