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arXiv · 1305.5407

Entropy as a measure of diffusion

Amir Aghamohammadi·Amir H. Fatollahi·Mohammad Khorrami·Ahmad Shariati
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Abstract

The time variation of entropy, as an alternative to the variance, is proposed as a measure of the diffusion rate. It is shown that for linear and time-translationally invariant systems having a large-time limit for the density, at large times the entropy tends exponentially to a constant. For systems with no stationary density, at large times the entropy is logarithmic with a coefficient specifying the speed of the diffusion. As an example, the large time behaviors of the entropy and the variance are compared for various types of fractional-derivative diffusions.

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Amir Aghamohammadi, Amir H. Fatollahi, Mohammad Khorrami, Ahmad Shariati. 2013-05-23. Entropy as a measure of diffusion. https://doi.org/10.1016/j.physleta.2013.05.015

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