Factors of type II_1 without non-trivial finite index subfactors
Operator Algebras
2009-01-20 v2
Abstract
We call a subfactor trivial if it is isomorphic with the obvious inclusion of N into matrices over N. We prove the existence of type II_1 factors M without non-trivial finite index subfactors. Equivalently, every M-M-bimodule with finite coupling constant, both as a left and as a right M-module, is a multiple of L^2(M). Our results rely on the recent work of Ioana, Peterson and Popa, who proved the existence of type II_1 factors without outer automorphisms.
Keywords
Cite
@article{arxiv.math/0610231,
title = {Factors of type II_1 without non-trivial finite index subfactors},
author = {Stefaan Vaes},
journal= {arXiv preprint arXiv:math/0610231},
year = {2009}
}
Comments
Smoothened presentation, final version