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arXiv · 1305.2113

Generalized Elastic Model: Fractional Langevin Description, Fluctuation Relation, and Linear Response

Alessandro Taloni·Aleksei Chechkin·Joseph Klafter
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Abstract

The Generalized Elastic Model is a linear stochastic model which accounts for the behaviour of many physical systems in nature, ranging from polymeric chains to single-file systems. If an external perturbation is exerted \emph{only} on a single point $\vec{x}^\star$ (\emph{tagged probe}), it propagates throughout the entire system. Within the fractional Langevin equation framework, we study the effect of such a perturbation, in cases of a constant force applied. We report most of the results arising from our previous analysis and, in the present work, we show that the Fox $H$-functions formalism provides a compact, elegant and useful tool for the study of the scaling properties of any observable. In particular we show how the generalized Kubo fluctuation relations can be expressed in terms of $H$-functions.

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Alessandro Taloni, Aleksei Chechkin, Joseph Klafter. 2013-05-09. Generalized Elastic Model: Fractional Langevin Description, Fluctuation Relation, and Linear Response. https://doi.org/10.1051/mmnp/20138202

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