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arXiv · 2608.26773

Brownian yet non-Gaussian diffusion through equilibrium nonlinear friction

Jakob Mihatsch·Andreas M. Menzel
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Abstract

In Brownian yet non-Gaussian diffusion (BnGD) the mean squared displacement grows linearly in time. However, the displacement statistics do not follow a normal distribution throughout. Typically, they are non-Gaussian at intermediate times, before they cross over to Gaussian in the long-time regime. We demonstrate that nonlinear friction under correctly applied stochastic equilibrium conditions provides an explanation of this phenomenon also for homogeneous environments.

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Jakob Mihatsch, Andreas M. Menzel. 2026-08-27. Brownian yet non-Gaussian diffusion through equilibrium nonlinear friction. https://arxiv.org/abs/2608.26773

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