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arXiv · 2609.35014

Ergodicity, ergodicity breaking, and temporal evolution of probability density in non-equilibrium: new perspectives by multispeckle DLS

Hans Joachim Schöpe
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Abstract

Testing the ergodicity hypothesis through experimentation in real systems is of crucial importance as it challenges a fundamental assumption underlying a wide range of theoretical models of physical and complex systems. High-calibre experiments can demonstrate whether, when and how a real system explores all of its possible states, and serve as a crucial conduit between abstract theoretical frameworks and tangible real-world applications. This approach is intended to guarantee that our descriptions of complex systems remain both physically meaningful and technologically relevant, thereby facilitating a more nuanced and comprehensive understanding. The development of a novel light scattering experiment has enabled us the direct measurement of the full distribution of fluctuations in the particle concentration in colloidal model systems and thus the direct determination of the probability distribution. This, in turn, facilitates the experimental verification of the ergodic hypothesis and the quantification of ergodicity breaking as a function of metastability.

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Hans Joachim Schöpe. 2026-09-28. Ergodicity, ergodicity breaking, and temporal evolution of probability density in non-equilibrium: new perspectives by multispeckle DLS. https://arxiv.org/abs/2609.35014

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