Failure of the fluctuation-dissipation relation to ensure equilibrium

A Bhattacharyay

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arXiv · 1007.0656

Failure of the fluctuation-dissipation relation to ensure equilibrium

A Bhattacharyay

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Abstract

Fluctuation-dissipation relation ensures thermodynamic equilibrium of a particle immersed in a heat bath. We will show that, under certain circumstances, the fluctuation-dissipation relation fails to ensure equilibrium between the immersed system and the heat bath. We consider a symmetry broken dimer, constrained to move in one dimension, is in compliance with the requirements of fluctuation-dissipation relation. An exact analytic result shows a nonzero average velocity of the center of mass of the dimer indicating that the state of the system is a nonequilibrium one. Based on this new physical observation, we propose an alternative paradigm for a Brownian motor which would extract useful energy directly from the heat bath unlike the ones based on Brownian Ratchet principle.

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A Bhattacharyay. 2010-08-30. Failure of the fluctuation-dissipation relation to ensure equilibrium. https://arxiv.org/abs/1007.0656

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