31. The problem of metric classification of systems is another important part of the abstract ergodic theory. 32. The assumption can be made by invoking the ergodic hypothesis as well as the Hamiltonian systems. 33. A chaotic Hamiltonian system need not be ergodic , although that is usually a good assumption. 34. In ergodic literature, nontrivial effort is required to allow the reader to traverse the text. 35. A stack of stained and mouldering newspapers, on the other hand, is ergodic literature. 36. Also, it is unknown if every C ^ 1 volume preserving Anosov diffeomorphism is ergodic . 37. Such characteristics include Lyapunov stability, Lyapunov time, various measurements from ergodic theory, etc. 38. In the 1930s, independently of John von Neumann, he discovered the mean ergodic theorem. 39. For an ergodic reversible Markov chain with an underlying mixing time in ergodic reversible Markov chains. 40. For an ergodic reversible Markov chain with an underlying mixing time in ergodic reversible Markov chains.