One of the basic characteristics of any physical system is its response to small perturbations. For instance, response is used to quantify material properties--such as conductivity and viscoelasticity--the sensing capability of cells, and the accuracy of biomolecular processes. Near thermodynamic equilibrium, response is completely determined by the nature of spontaneous fluctuations, according to the fluctuation-dissipation theorem (FDT). This deep connection forms the basis of powerful experimental techniques, but also implies that highly-responsive equilibrium devices are always plagued by noise . In this work, we present equalities and inequalities--akin to the FDT but valid arbitrarily far from equilibrium--that link response to the strength of nonequilibrium driving. Our results open new possibilities to experimentally characterize away-from-equilibrium response and suggest design principles for high-sensitivity, low-noise devices . As illustrations, we show how our results rationalize the energetic requirements of biochemical switches and kinetic proofreading .
Diverse physical systems are characterized by their response to small perturbations. Near thermodynamic equilibrium, the fluctuation-dissipation theorem provides a powerful theoretical and experimental tool to determine the nature of response by observing spontaneous equilibrium fluctuations . In this spirit, we derive here a collection of equalities and inequalities valid arbitrarily far from equilibrium that constrain the response of nonequilibrium steady states in terms of the strength of nonequilibrium driving. Our work opens new avenues for characterizing nonequilibrium response . As illustrations, we show how our results rationalize the energetic requirements of two common biochemical motifs .
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One of the basic characteristics of any physical system is its
Diverse physical systems are characterized by their
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For instance, response is used to quantify material properties--such as conductivity and viscoelasticity--the sensing capability of cells, and the accuracy of biomolecular processes.
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response is completely determined by the nature of spontaneous fluctuations, according to the
the
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(FDT). This deep connection forms the basis of powerful experimental techniques, but also implies that highly-responsive equilibrium devices are always plagued by noise
provides a powerful theoretical and experimental tool to determine the nature of response by observing spontaneous equilibrium fluctuations
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work, we present equalities and inequalities--akin to the FDT but
spirit, we derive here a collection of equalities and inequalities
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equilibrium--that link response to
equilibrium that constrain the response of nonequilibrium steady states in terms of
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results open new possibilities to experimentally characterize away-from-equilibrium response and suggest design principles for high-sensitivity, low-noise devices
work opens new avenues for characterizing nonequilibrium response
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biochemical switches and kinetic proofreading
two common biochemical motifs