Texas A&M University, Department of
Mathematics, 216 Milner Hall, 21st of September 2005, 3:00-3:50
Groups and Dynamics Seminar
Amenable actions of
nonamenable groups
Volodymyr Nekrashevych of Texas A&M
University
We give two ways of constructing amenable (in the sense of Greenleaf)
actions of non-amenable groups.
In the first part we construct a class of faithful transitive amenable
actions of the free group using Schreier graphs.
In the second part we show that every finitely generated residually
finite group can be embedded into a residually finite group that acts
level-transitively on a locally finite rooted tree, so that the induced
action on the boundary of the tree is amenable on every orbit.