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arXiv · 2603.08116

Probing scale-dependent liveliness with nonequilibrium thermospectroscopy

Joscha Mecke·Klaus Kroy
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Abstract

Probing the spatially heterogeneous activity across scales is a major challenge in living matter. Energy injection at diverse length scales leads to mode coupling, inter-modal energy transfer, and entropy production. We demonstrate the emergence of multiple effective (``active'') temperatures in nonequilibrium molecular- and Brownian-dynamics simulations of an active polymer. Via a generalised Langevin equation for a labelled monomer we identify spectral noise temperatures and their relation to the underlying activity landscape. A harmonic trap of variable stiffness can serve as a minimally invasive prototypical spectroscopic device to selectively scan through the emergent effective temperatures and thereby resolve the scale-dependent activity.

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Joscha Mecke, Klaus Kroy. 2026-03-09. Probing scale-dependent liveliness with nonequilibrium thermospectroscopy. https://arxiv.org/abs/2603.08116

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