A capture problem in Brownian motion and eigenvalues of spherical domains

Abstract

We resolve a question of Bramson and Griffeath by showing that the expected capture time of four predators pursuing a single prey, all moving by standard Brownian motion on a line, is finite. Our main tool is an eigenvalue estimate for a particular spherical domain, which we obtain by a coning construction and domain perturbation. © 2008 American Mathematical Society.