The Ergodic hypothesis (Ref 1 and 2) essentially states that an ensemble average (MC) of an observable,
is equivalent to the time average,
of an observable (MD). i.e.
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A restatement of the ergodic hypothesis is to say that all allowed states are equally probable.
References
- George D. Birkhoff, "Proof of the Ergodic Theorem", PNAS 17 pp. 656-660 (1931)
- [LAS_1987_15_0263]