TOPICS IN GEOMETRIC GROUP THEORY
FALL 2005 MATH 595 Section TGT
MWF, 10am Altgeld
Hall, rm 445
WWW:
http://www.math.uiuc.edu/~kapovich/595-05/595-05.html
Telephone:
265-0633
e-mail: kapovich@math.uiuc.edu. (Preferred
method
of reaching me!)
Office location: Altgeld Hall, room 365
Office hours (preliminary): Tuesday
4:00-5:30pm,
Thursday, 10am-11:30am AND by appointment
Text:
There is no official required textbook for this course.
Recommended sources are:
- Topics in
Geometric Group Theory, by P. de la Harpe, University of
Chicago Press, 2000
- Cominatorial
Group Theory, by R. Lyndon and P. Schupp,
Springer-Verlag, 2001; ("Classics in Mathematics series'', reprint of
the 1977 edition)
- Lecture notes on Geometric Group Theory
[pdf file], by Michael Kapovich (be aware that there are lots of
misprints in this file); a postscript
version is available here.
Brief course description.
The first part of
the course will be devoted to proving Gromov's
theorem about characterizing finitely generated groups of polynomial
growth, which is one of the most beautiful and important results in
Geometric Group theory in the last 30 years.
We will then cover a number of topics related to growth of groups and
to volume entropy, such as amenability of finitely generated groups
(including its various geometric, analytic and probabilistic
characterizations) and random walks on graphs and groups. We will
discuss some of the modern developments in this area related to
uniform amenability, uniformly exponential growth, growth tightness,
topological amenability, Kazhdan's property T, etc. Time
permitting we will consider in
more detail some important examples, such as Thompson's groups and
Grigorchuk's groups of intermediate growth.
There are no formal prerequisites for this course but the participants
are expected to be somewhat familiar with such notion as free groups,
groups given by generators and relators, smooth manifolds and Lie
groups.
Nevertheless, I
will try to teach this course in a way that does not assume much
advanced knowledge and is suitable as an introductory course to the
subject.
At the end of the course
I will expect each student to make a
presentation
on some paper (I will provide a number of choices) that is reasonably
short,
self-contained and yet concerns some recent developments in Geometric
Group Theory. You can also choose a paper not from my
list, but I'll have to approve it first.