English

On Akemann-Weaver Conjecture

Functional Analysis 2023-03-24 v1 Combinatorics

Abstract

Akemann and Weaver showed Lyapunov-type theorem for rank one positive semidefinite matrices which is an extension of Weaver's KS2_2 conjecture that was proven by Marcus, Spielman, and Srivastava in their breakthrough solution of the Kadison-Singer problem. They conjectured that a similar result holds for higher rank matrices. We prove the conjecture of Akemann and Weaver by establishing Lyapunov-type theorem for trace class operators. In the process we prove a matrix discrepancy result for sums of hermitian matrices. This extends rank one result of Kyng, Luh, and Song who established an improved bound in Lyapunov-type theorem of Akemann and Weaver.

Keywords

Cite

@article{arxiv.2303.12954,
  title  = {On Akemann-Weaver Conjecture},
  author = {Marcin Bownik},
  journal= {arXiv preprint arXiv:2303.12954},
  year   = {2023}
}
R2 v1 2026-06-28T09:29:03.761Z