Let L be the Liouvillean of an ergodic quantum dynamical system $(\mathfrak{M} ,\tau,\omega)$. We give a new proof of the theorem of Jadczyk that eigenvalues of L are simple and form a subgroup of $\mathbb{R}$ . If $\omega$ is a $(\tau, \beta)$-KMS state for some $\beta>0$ we show that this subgroup is trivial, namely that zero is the only eigenvalue of L. Hence, for KMS states ergodicity is equivalent to weak mixing.
@article{hal-00005460,
author = {Pillet, Claude-Alain and Jaksic, Vojkan},
title = {A Note on Eigenvalues of Liouvilleans},
journal = {HAL},
volume = {2001},
number = {0},
year = {2001},
language = {en},
url = {http://dml.mathdoc.fr/item/hal-00005460}
}
Pillet, Claude-Alain; Jaksic, Vojkan. A Note on Eigenvalues of Liouvilleans. HAL, Tome 2001 (2001) no. 0, . http://gdmltest.u-ga.fr/item/hal-00005460/