## Bio

I graduated from Johns Hopkins in 1977, and got my PhD, under Gregg Zuckerman, at Yale in 1981. I have been on the faculty at the University of Maryland since 1986.

## Teaching

In the Fall 2018 I am teaching Math 246 (Differential Equations) and Math 401 (Applied Linear Algebra). I am teaching Math 401 as a flipped class. I have made a complete set of videos for the class, which students watch before class. Class is run as a discussion. You are

to view the [complete set of videos|http://www.math.umd.edu/~jda/linearalgebravideos.html], and use them in your own teaching. If you use them please send me an emailand let me know, and give me feedback.

## Research

I study representation theory of Lie groups and algebraic groups. Lie groups (named after the Norwegian mathematician Sophus Lie) are the abstract mathematical underpinning of the notion of symmetry. Lie groups and their representations are ubiquitous in mathematics, and play a central role in the Langlands program in

number theory.

For the past 15 years I have been the head of the *Atlas of Lie groups and representations*, which is a project to study representations of Lie groups using a computer. One of the main goals is to solve the {italic: Unitary Dual} problem: to compute all of the representations of a Lie group which preserve a

positive definite Hermitian form. The *atlas* software is freely available from the atlas web site

www.liegroups.org.