Introduction to Ergodic Theory, Paperback by Sinai, Ya G.; Scheffer, V. (TRN), ISBN 0691081824, ISBN-13 9780691081823, Brand New, Free shipping in the US Based on lectures in Erevan, this exposition of ergodic theory contains a rich collection of examples well chosen to introduce the reader to the main themes of the subject. Topics discussed include existence of invariant measures, geodesic flows on Riemannian manifolds, ergodic theory of an ideal gas, and entropy of dynamical systems.