SOME PROPERTIES OF FREE SHIFTS ON INFINITE FREE PRODUCT FACTORS

摘要

In this work we study a special class of shift automorphisms on an infinite free product of von Neumann algebras. This is a generalisation of some results in [12]. The automorphisms are shown to be extremely ergodic, i.e. all non-trivial globally invariant von Neumann sub-algebras are full factors. As a special case we derive a result of Popa [12]. In this case the automorphisms are known to have Connes-St0rmer entropy 0 by [14].