Spectral bound for separations in Eulerian digraphs

Abstract: The spectra of digraphs, unlike those of graphs, is a relatively unexplored territory. In a digraph, a separation is a pair of sets of vertices X and Y such that there are no arcs from X and Y . For a subclass of eulerian digraphs, we give an bound on the size of a separation in terms of the eigenvalues of the Laplacian matrix.