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arXiv · 1901.11192

Hybrid Einstein-Langevin Approach for Microscopic formulation of Viscous Drag: An Alternative to the Langevin Equation

P. D. Gujrati
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Abstract

We present a novel hybrid but thermodynamic approach to provide an alternative to the Langevin equation by using system-intrinsic (SI) microwork done by the Brownian particle in the kth microstate (realization). The corresponding SI-microforce is unique to the microstate and determines the microscopic equation of motion for it. Being a thermodynamic approach, the equipartition theorem is always satisfied and no additional stochastic Langevin force is needed. We determine instantaneous and long-time averages of useful quantities and thus provide a new unified approach to the fluctuating motion from mesoscopic to macroscopic scales.

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P. D. Gujrati. 2019-01-31. Hybrid Einstein-Langevin Approach for Microscopic formulation of Viscous Drag: An Alternative to the Langevin Equation. https://arxiv.org/abs/1901.11192

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