Random walks on algebraic structures,
in particular, matrix semigroups. Semigroup approaches to discrete dynamical
systems, especially the road coloring problem. Development of mathematics curriculum
based on "Mathematically-rich" experiences.
Convolution Products of Non-identical
Distributions on A Topological Semigroup, Journal of Theoretical Probability,
Vol. 5, No. 2, pp. 283-307 (1992). (with A. Mukherjea)
Semigroup Approach to the Road Coloring Problem, Contemporary Mathematics,
Vol. 261, pp. 195-207 (2000). (with A. Mukherjea).
and the Generalized Road Coloring Problem, Semigroup Forum,
Vol. 69, pp. 201-208 (2004).
Convolution Products of Probability Measures on Completely Simple Semigroups, Journal of Mathematical Analysis and Applications, Vol. 317, pp.
Completely Simple Semigroups,
Lie Algebras, and the Road Coloring Problem, Semigroup Forum, Vol.
74, pp. 206-226 (2007). (with P. Feinsilver )