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arXiv · 0707.3865

Distribution of Time-Averaged Observables for Weak Ergodicity Breaking

Adi Rebenshtok·Eli Barkai
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Abstract

We find a general formula for the distribution of time-averaged observables for systems modeled according to the sub-diffusive continuous time random walk. For Gaussian random walks coupled to a thermal bath we recover ergodicity and Boltzmann's statistics, while for the anomalous subdiffusive case a weakly non-ergodic statistical mechanical framework is constructed, which is based on Lévy's generalized central limit theorem. As an example we calculate the distribution of $\bar{X}$: the time average of the position of the particle, for unbiased and uniformly biased particles, and show that $\bar{X}$ exhibits large fluctuations compared with the ensemble average $ $.

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Adi Rebenshtok, Eli Barkai. 2007-07-26. Distribution of Time-Averaged Observables for Weak Ergodicity Breaking. https://doi.org/10.1103/physrevlett.99.210601

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