talks.shtml

Transparencies from talks by Dave Witte Morris

Lattices in SL(3,R)
May 2013 at University of Chicago
PDF file

Strictly convex norms on amenable groups
March 2013 at South Padre Island, Texas (Geometric Groups on the Gulf Coast)
April 2012 at University of Lethbridge
March 2012 at University of Chicago
March 2012 at Indiana University
March 2012 at Purdue University
    Lecture 1: Strictly convex norms on abstract groups (PDF file)
    Lecture 2: Strictly convex norms on amenable groups (PDF file)

SL(n,Q) has no volume-preserving actions on (n-1)-dimensional compact manifolds
May 2013 at the University of Chicago
March 2013 at Rice University
July 2012 at Oberwolfach
    PDF file

Introduction to vertex-transitive graphs of prime-power order
March 2013 at the University of Lethbridge
PDF file

Hamiltonian paths in solvable Cayley digraphs
October 2012 at the University of Lethbridge
July 2011 in Regina
June 2011 in Bled (7th Slovenian International Conference on Graph Theory)
PDF file

Some arithmetic groups that do not act on the circle
July 2012 at Park City Mathematics Institute
    Lecture 1: Introduction (PDF file)
    Lecture 2: Proof using bounded generation (PDF file)
    Lecture 3: What is an amenable group? (PDF file)
    Lecture 4: Introduction to bounded cohomology (PDF file)

On interactions of amenability with left orderings
February 2012 at workshop in Banff
    PDF file

Does every Cayley graph have a hamiltonian cycle?
March 2011 at University of Western Australia
    PDF file

another talk on a similar subject (and others can be found below):

Survey of hamiltonian cycles in Cayley graphs
May 2010 at AMS meeting in Newark
PDF file

When do subsets of {0,1}^G^x^G contain recurrent points?
December 2010 in Vancouver (Canadian Mathematical Society)
    PDF file

Why arithmetic groups are lattices
June 2010 at the University of Chicago
    PDF file

Survey of invariant orders on arithmetic groups
September 2011 in AMS Sectional meeting at Cornell
June 2011 at Oberwolfach
June 2010 at the University of Chicago
October 2009 in AMS Sectional meeting at Penn State
    PDF file

Introduction to Ratner's Theorems on Unipotent Flows
June 2010 at Ohio State University
March 2010 at the University of British Columbia
April 2009 at the University of Virgina
    PDF file

other talks on a similar subject:

Ratner's Theorems
June 2010 at Ohio State U (two 1.5-hour lectures)
PDF file

Introduction to arithmetic groups
January 2010 at KAIST in Daejeon, Korea (three 1.5-hour lectures)
PDF file

What is the Congruence Subgroup Property?
September 2009 at Carleton-Ottawa Algebra Day
PDF file

other talks on a similar subject:

The Congruence Subgroup Property and bounded generation
May 2008 at the University of Chicago

Lecture 1: Introduction to the Congruence Subgroup Property
Lecture 2: Proof that SL(3,Z) has the Congruence Subgroup Property
Lecture 3: Bounded generation

A lattice with no torsion-free subgroup of finite index (after P.Deligne)
June 2009 informal discussion at the University of Chicago
PDF file

Two lectures on bounded cohomology
June 2009 at the University of Chicago
PDF file

Locally symmetric subspaces of locally symmetric spaces
(joint work with Vladimir Chernousov and Lucy Lifschitz)
January 2009 at AMS meeting in Washington, DC
September 2008 at Oberwolfach
April 2008 at Indiana University
February 2008 at the University of Chicago
PDF file of slides from recent talk
PDF file of lecture notes from older talk

other talks on the same subject:

Minimal isotropic simple Q-groups of higher real rank
February 2008 at the University of Virginia
PDF file

Almost-minimal lattices of higher rank
May 2006 at the University of Chicago
PDF file

Using left-invariant orders to study actions on 1-manifolds
June 2008 at CIRM, Luminy, France

Lecture 1: Left-invariant orders and local indicability
Lecture 2: Amenability and Ghys-Burger-Monod Theorem
Lecture 3: Ghys-Burger-Monod Theorem and a theorem of Navas

Proof of the Margulis Normal Subgroups Theorem
February 2008 at the University of Chicago

Lecture 1: Introduction to Amenable Groups (PDF file)
Lecture 2: Statement and Most of the Proof (PDF file)
Lecture 3: Proof of the 'Black Box' Result (PDF file)

Amenable groups that act on the line
April 2008 at University of Illinois, Chicago
April 2008 at Northwestern University
April 2008 at AMS meeting in Bloomington, Indiana
February 2008 at Ohio State University
March 2007 at the University of British Columbia
November 2006 at the University of Alberta
October 2006 at the University of Karlsruhe
PDF file

a more elementary talk on the same subject:

    Using recurrence to study symmetries of the real line
    March 2012 at the University of Virginia
    PDF file

Dani's contributions to ergodic theory on homogeneous spaces
December 2007 at Tata Institute in Mumbai, India
PDF file

Application of Bost's Theorem to subgroups of algebraic groups
(a lecture in a course given by B.Farb and M.Kisin)
October 2007 at the University of Chicago
PDF file

Some discrete groups that cannot
act on 1-dimensional manifolds
July 2007 in workshop on amenability
at Schrodinger Institute in Vienna

Part 1: Actions of amenable groups (PDF file)
Part 2: Actions of arithmetic groups (PDF file)
Part 3: 3 Major Theorems of Margulis (PDF file)
(Theorems in Part 3 are not part of the announced topic,
but are important and use methods similar to Part 2)

Which circulant digraphs are hamiltonian?
June 2007 in Koper, Slovenia
PDF file

Bounded generation of special linear groups (after Carter, Keller, and Paige)
April 2008 at Vanderbilt University
June 2005 at workshop in Banff
PDF file

Actions of arithmetic groups on the circle
April 2005 at the University of Illinois, Chicago
PDF file

other talks on the same or a related subject:

Some arithmetic groups that cannot act on the line
(joint work with Lucy Lifschitz and Vladimir Chernousov)
Alternate titles:
Some arithmetic groups that cannot act on the circle,
Some arithmetic groups that cannot act on 1-manifolds,
Some arithmetic groups that cannot be right ordered
March 2012 at Purdue University
April 2010 at the University of Virginia
December 2009 at the University of Lethbridge
April 2008 at Vanderbilt University
February 2008 at the University of Virginia
January 2008 at Mississippi State University
January 2008 at the University of Texas
July 2007 at the University of Minnesota, Duluth
March 2007 at the University of British Columbia
July 2006 at Oberwolfach, Germany
March 2006 at the University of Hawaii
November 2005 at Texas A&M University
March 2005 at AMS meeting in Lubbock, Texas
March 2005 at Princeton University
March 2005 at AMS meeting in Newark, Delaware
March 2005 at Rice University
February 2005 in Auckland, New Zealand
November 2004 at the University of Alberta
November 2004 at Lorentz Dynamics Workshop in Banff
August 2004 at Alberta Topology Seminar in Banff
June 2004 at Caltech
April 2004 at the University of Regina
PDF file
Some arithmetic groups that cannot act on the circle
(alternate title: Arithmetic groups that cannot be right-ordered )
December 2001 at Tata Institute (Mumbai, India)
February 2002 at Case Western Reserve University and Virginia Tech
PDF file
Some arithmetic groups that cannot act on the circle
March 2002 at Les Diablerets, Switzerland
PDF file
SL(3,Z) cannot act continuously on the circle
October 1998 at the Ecole Normale Superieure - Lyon (France)
PDF file

Actions of semisimple Lie groups on circle bundles
(joint work with Robert J. Zimmer)
May 2000 at the Newton Institute (Cambridge, UK)
March 2000 at the University of Manchester, England
PDF file

Cocompact Lattices
January 2006 in Workshop on Property RD
at the American Institute of Mathematics, Palo Alto
PDF file

Hamiltonian checkerboards
November 2011 at the University of Lethbridge
May 2010 at the University of Manitoba
(Prairie Discrete Mathematics Conference)
PDF file

other talks on related subjects:

Hamiltonian cycles in Cayley graphs
August 2005 at the University of Winnipeg
(Prairie Discrete Mathematics Conference)
PDF file

Open problems on hamiltonian cycles in Cayley graphs
June 2006 in Minisymposium in SIAM conference
at University of Victoria
PDF file

Hamiltonian cycles in circulant graphs and digraphs
May 2004 at the University of Lethbridge
(Combinatorics Day)
PDF file

Hamiltonian paths and cycles in vertex-transitive graphs and digraphs
May 2003 at Simon Fraser University
(conference for Brian Alspach's 65th birthday)
PDF file

Which flows are sums of hamiltonian cycles in abelian Cayley graphs?
(joint work with Joy Morris and David Petrie Moulton )
May 2003 in Koper, Slovenia (Algebraic Combinatorics on the Adriatic Coast)
PDF file

Flows that are sums of hamiltonian cycles in abelian Cayley graphs
(joint work with Joy Morris and David Petrie Moulton )
March 2002 at Southeastern Combinatorics Conference in Boca Raton, Florida
PDF file

Hamiltonian paths in cartesian powers of directed cycles
(joint work with David Austin and Heather Gavlas)
November 2002 at the University of Lethbridge
PDF file

Touring a torus (alternate title: Hamiltonian Checkerboards)
March 2008 at the University of Michigan
April 2002 at the University of Lethbridge, Canada
November 2001 at Oklahoma State University
This is an undergraduate-level talk.
PDF file

Geometric interpretation of the Q-rank of a locally symmetric space
May 2004 at AMS/SMM Meeting in Houston
(joint work with Pralay Chatterjee)
PDF file

another talk on a related subject:

Orbits of Cartan subgroups on homogeneous spaces
(after George Tomanov and Barak Weiss)
December 2001 at Tata Institute (Mumbai, India)
PDF file

Real representations of sp(n) have Q-forms
April 2003 at the University of North Carolina
PDF file

another talk on a related subject:

Q-forms of real representations of compact semisimple Lie groups
(after Raghunathan and Eberlein)
October 2001 at OSU
PDF file

Gromov and Piatestski-Shapiro's Nonarithmetic Lattices in SO(1,n)
September 2002 at Oklahoma State University
PDF file

Some ideas in the proof of Ratner's Theorem
(alternate title: An Introduction to Unipotent Flows)
September 2007 at Pennsylvania State University
January 2007 at University of Calgary
July 2002 at ETH, Zurich
June 2002 at the University of Chicago
February 2000 at the Newton Institute (Cambridge, UK)
previously at a few other universities
PDF file

Ergodic actions of semisimple Lie groups on compact principal bundles
(joint work with Robert J. Zimmer)
April 2001 at the University of Illinois, Chicago
PDF file

Rigidity of some characteristic-p nillattices
(joint work with Lucy Lifschitz)
June 2000 at the Newton Institute (Cambridge, UK)
PDF file

Superrigid subgroups of solvable Lie groups
(alternate title: What is a superrigid subgroup? )
May 2000 at the University of Birmingham, England
February 2002 at Virgina Tech
April 2002 at the University of Regina, Canada
PDF file

Other talks on the same subject:
More elementary: What is a superrigid subgroup? (August 1997 at the MAA Mathfest, Atlanta)
More advanced: Superrigid subgroups of solvable Lie groups (April 1999 at the U of Chicago)

Tessellations of homogeneous spaces of SU(2,n)
(joint work with Alessandra Iozzi and Hee Oh )
March 2000 at the Newton Institute (Cambridge, UK)
PDF file

Cartan-decomposition subgroups
(joint work with Hee Oh and Alessandra Iozzi )
September 1999 at the University of Michigan
PDF file

Transitive permutation groups of prime-squared degree
(joint work with Edward Dobson)
May 1999 Group Theory Junior Seminar at the University of Chicago
PDF file

Foliation-preserving maps between solvmanifolds
(joint work with Holly Bernstein)
March 1998 at Kansas State University AMS meeting
PDF file

Simple groups of real rank at least two have Kazhdan's property T
January 28, 1998 Lie Groups Seminar at Oklahoma State University
PDF file

Introduction to Kazhdan's property T
January 21, 1998 Lie Groups Seminar at Oklahoma State University
PDF file