English

Conditional expectations onto maximal abelian *-subalgebras

Operator Algebras 2009-06-11 v2 Functional Analysis

Abstract

We determine when there is a unique conditional expectation from a semifinite von Neumann algebra onto a singly-generated maximal abelian *-subalgebra. Our work extends the results of Kadison and Singer via new methods, notably the observation that a unique conditional expectation onto a singly-generated maximal abelian *-subalgebra must be normal.

Cite

@article{arxiv.0906.1831,
  title  = {Conditional expectations onto maximal abelian *-subalgebras},
  author = {Charles A. Akemann and David Sherman},
  journal= {arXiv preprint arXiv:0906.1831},
  year   = {2009}
}

Comments

8 pages; a remark was corrected

R2 v1 2026-06-21T13:11:39.677Z