Recall a projection $p\in N$ is called abelian if $pNp$ is an abelian algebra.
If $N$ is a von Neumann algebra without abelian projections, then can we conclude that $N$ must be infinite dimensional?
Recall a projection $p\in N$ is called abelian if $pNp$ is an abelian algebra.
If $N$ is a von Neumann algebra without abelian projections, then can we conclude that $N$ must be infinite dimensional?
Copyright © 2021 JogjaFile Inc.
Yes. Because a finite-dimensional von Neumann algebra will always have minimal projections, and minimal projections are abelian.