Conditions for strong ergodicity using intensity matrices

Sufficient conditions for strong ergodicity of discrete-time non-homogeneous Markov chains have been given in several papers. Conditions have been given using the left eigenvectors ψn of Pn(ψnPn=ψn) and also using the limiting behavior of Pn. In this paper the authors consider the analogous results in the case of continuous-time Markov chains were one uses the intensity matrices Q(t) instead of P(s,t). A bound on the rate of convergence of certain strongly ergodic chains is also given.