A Taste of Chromatic Roots: Theta Graphs
by
Jason I. Brown
Department of Mathematics and Statistics, Dalhousie University
Coauthors: Carl Hickman, University College of Cape Breton, Alan D. Sokal, New York University, David G. Wagner, University of Waterloo

Chromatic roots, the roots of chromatic polynomials, are a tantalizing treat, offering many an inviting conjecture. In this talk we'll discuss recent work on the chromatic roots of a seemingly simple family of graphs, theta graphs. Much to our surprise, chromatic roots of theta graphs provide a healthy (and nontrivial) entree, rather than merely an appetizer. Our analysis yields new information on such topics as chromatic roots with negative real part and families of graphs with sublinear growth of the maximum modulus of their chromatic roots.

Date received: May 10, 2001