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arXiv · 2401.03509

The fluctuation-dissipation relation holds for a macroscopic tracer in an active bath

Dima Boriskovsky·Benjamin Lindner·Yael Roichman
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Abstract

The fluctuation-dissipation relation (FDR) links thermal fluctuations and dissipation at thermal equilibrium through temperature. Extending it beyond equilibrium conditions in pursuit of broadening thermodynamics is often feasible, albeit with system-dependent specific conditions. We demonstrate experimentally that a generalized FDR holds for a harmonically trapped tracer colliding with self-propelled walkers. The generalized FDR remains valid across a large spectrum of active fluctuation frequencies, extending from underdamped to critically damped dynamics, which we attribute to a single primary channel for energy input and dissipation in our system.

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Dima Boriskovsky, Benjamin Lindner, Yael Roichman. 2024-01-07. The fluctuation-dissipation relation holds for a macroscopic tracer in an active bath. https://doi.org/10.1039/d4sm00808a

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