We analyze the asymptotic behavior of general first order Laplacian processes
on digraphs. The most important ones of these are diffusion and consensus with
both continuous and discrete time. We treat diffusion and consensus as dual
processes. This is the first complete exposition of this material in a single
work.Comment: 24 pages, 5 figures, summer-school/conference on mathematical
modeling of complex systems in Pescara, 201
