Professor at University of California, Davis

Department of Mathematics,

1 Shields Ave., University of California, 

Davis, CA 95616 

My research areas are:

Low dimensional geometry and topology. 

Hyperbolic geometry. 

Discrete subgroups of Lie groups. 

Representation varieties of finitely generated groups.

Configuration spaces of elementary geometric objects, like arrangements and mechanical linkages.

Fundamental groups of Kaehler manifolds and algebraic varieties.

Differential geometry, especially manifolds of nonpositive curvature. 

Geometric group theory.

Geometric representation theory of Lie groups.  

Links to computer animation based on some of my work on linkages:

Here, a computer animation of the Peaucellier linkage.

Here a computer animation of a part of our (with John Millson) proof of Kempe's linkage theorem.