Algebra Seminar: Combes -- Automorphism groups of rooted trees

Lewis Combes (University of Sydney) will be speaking in the algebra seminar.  We will go
out for lunch after the talk---all are welcome to join! 

When: 12-1pm Friday May 16 

Where: Carslaw 175 

Title: Automorphism groups of rooted trees 

Abstract: In this talk we will discuss groups whose elements arise as automorphisms of
finite and infinite trees.  Of particular interest are automorphism groups of regular
trees, which display self-similarity properties, leading to strange and often
counterintuitive phenomena.  We will discuss the Grigorchuk group, a group famous for
having many interesting properties, as well as some other groups, and some links to
topology and number theory.  The talk is expository and aimed at a wide audience.