Fluctuating entropy production on the coarse-grained level: Inference and localization of irreversibility

Physical Review Research, Год журнала: 2024, Номер 6(2)

Опубликована: Май 16, 2024

Stochastic thermodynamics provides the framework to analyze thermodynamic laws and quantities along individual trajectories of small but fully observable systems. If level fails capture all relevant degrees freedom, some form effective, coarse-grained dynamics naturally emerges for which principles stochastic generally cease be applicable straightforwardly. Our work unifies notion entropy production an trajectory with that a by establishing based on snippets Markovian events as fundamental building blocks. A key asset trajectory-based fluctuating is ability localize contributions total in time space. As illustration potential application inference we introduce method detection hidden driving. The applies equally even odd variables and, therefore, includes peculiar case underdamped Langevin dynamics. Published American Physical Society 2024

Язык: Английский

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Bayesian mechanics for stationary processes

Proceedings of the Royal Society A Mathematical Physical and Engineering Sciences, Год журнала: 2021, Номер 477(2256)

Опубликована: Дек. 1, 2021

This paper develops a Bayesian mechanics for adaptive systems. Firstly, we model the interface between system and its environment with Markov blanket. affords conditions under which states internal to blanket encode information about external states. Second, introduce dynamics represent systems as blankets at steady state. allows us identify wide class of whose appear infer states, consistent variational inference in statistics theoretical neuroscience. Finally, partition into sensory active It follows that can be seen performing well-known forms stochastic control (such PID control), are prominent formulations behaviour biology engineering.

Язык: Английский

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Phenotyping single-cell motility in microfluidic confinement

eLife, Год журнала: 2022, Номер 11

Опубликована: Ноя. 23, 2022

The movement trajectories of organisms serve as dynamic read-outs their behaviour and physiology. For microorganisms this can be difficult to resolve due small size fast movement. Here, we devise a novel droplet microfluidics assay encapsulate single micron-sized algae inside closed arenas, enabling ultralong high-speed tracking the same cell. Comparing two model species - Chlamydomonas reinhardtii (freshwater, 2 cilia), Pyramimonas octopus (marine, 8 detail highly-stereotyped yet contrasting swimming behaviours environmental interactions. By measuring rates probabilities with which cells transition between trio motility states (smooth-forward swimming, quiescence, tumbling or excitable backward swimming), reconstruct control network that underlies gait switching dynamics. A simplified cell-roaming in circular confinement reproduces observed long-term spatial fluxes, including boundary circulation behaviour. Finally, establish an pairs droplets are fused on demand, one containing trapped cell another chemical perturbs cellular excitability, reveal how aneural adapt locomotor patterns real-time.

Язык: Английский

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Energy and information flows in autonomous systems

Frontiers in Physics, Год журнала: 2023, Номер 11

Опубликована: Апрель 6, 2023

Multi-component molecular machines are ubiquitous in biology. We review recent progress on describing their thermodynamic properties using autonomous bipartite Markovian dynamics. The first and second laws can be split into separate versions applicable to each subsystem of a two-component system, illustrating that one not only resolve energy flows between the subsystems but also information quantifying how subsystem’s dynamics influence joint system’s entropy balance. Applying framework molecular-scale sensors allows derive tighter bounds requirement. Two-component strongly coupled studied from unifying perspective what extent they operate conventionally by transducing power or like an engine generating flow rectify thermal fluctuations output power.

Язык: Английский

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Random walk with horizontal and cyclic currents

Physical review. E, Год журнала: 2025, Номер 111(1)

Опубликована: Янв. 8, 2025

We construct a minimal two-chain random walk model and study the information that fluctuations of flux higher cumulants can reveal about model: its structure, parameters, whether it operates under nonequilibrium conditions. The two coupled chains allow for both horizontal cyclic transport. capture these processes by deriving cumulant generating function system, which characterizes transport in long time limit. First, we show either or currents, along with their higher-order cumulants, be used to unravel intrinsic structure parameters model. Second, investigate "zero current" situation, current vanishes. find condition at intermediate bias, while remains nonzero throughout. also scenarios close zero limit, entropy production rate is more tightly lower-bounded relative noise current, vice versa. Finally, simulations before steady state sets extraction interchain hopping rate. Our study, illustrating concealed fluctuations, could see applications chemical networks, cellular processes, charge energy materials.

Язык: Английский

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Conditional fluctuation theorems and entropy production for monitored quantum systems under imperfect detection

Physical Review Research, Год журнала: 2025, Номер 7(1)

Опубликована: Янв. 21, 2025

The thermodynamic behavior of Markovian open quantum systems can be described at the level fluctuations by using continuous monitoring approaches. However, practical applications require assessing imperfect detection schemes, where definition main quantities becomes subtle and universal fluctuation relations are unknown. Here, we fill this gap deriving a relation that links entropy production information-theoretical irreversibility along single trajectories in inefficient setups. This provides as corollary an estimator dissipation records lower bounds underlying visible trajectories. We illustrate our findings with driven-dissipative two-level system following jump discuss experimental applicability results for inference. Published American Physical Society 2025

Язык: Английский

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Fluctuations of entropy production of a run-and-tumble particle

Physical review. E, Год журнала: 2023, Номер 107(1)

Опубликована: Янв. 18, 2023

Out-of-equilibrium systems continuously generate entropy, with its rate of production being a fingerprint nonequilibrium conditions. In small-scale dissipative subject to thermal noise, fluctuations entropy are significant. Hitherto, mean and variance have been abundantly studied, even if higher moments might be important fully characterize the system interest. Here, we introduce graphical method compute any moment for generic discrete-state system. Then, focus on paradigmatic model active particles, i.e., run-and-tumble dynamics, which resembles motion observed in several micro-organisms. Employing our framework, first three cumulants discrete version this model. We also compare analytical results numerical simulations. find that as number states increases, distribution deviates from Gaussian. Finally, extend framework continuous state-space model, using an appropriate scaling transition rates. The approach presented here help uncover features current biological operating out-of-equilibrium.

Язык: Английский

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Universal bounds on entropy production inferred from observed statistics

Physical Review Research, Год журнала: 2023, Номер 5(4)

Опубликована: Дек. 15, 2023

Nonequilibrium processes break time-reversal symmetry and generate entropy. Living systems are driven out-of-equilibrium at the microscopic level of molecular motors that exploit chemical potential gradients to transduce free energy mechanical work, while dissipating energy. The amount dissipation, or entropy production rate (EPR), sets thermodynamic constraints on cellular processes. Practically, calculating total EPR in experimental is challenging due limited spatiotemporal resolution lack complete information every degree freedom. Here, we propose an inference approach for a tight lower bound given partial information, based optimization scheme uses observed transitions waiting times statistics. We introduce hierarchical bounds relying first- second-order transitions, moments time distributions, apply our two generic hidden network motor, with lumped states. Finally, show can be obtained even when assuming simpler topology full system.

Язык: Английский

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Effective estimation of entropy production with lacking data

Communications Physics, Год журнала: 2024, Номер 7(1)

Опубликована: Авг. 3, 2024

Observing stochastic trajectories with rare transitions between states, practically undetectable on time scales accessible to experiments, makes it impossible directly quantify the entropy production and thus infer whether how far systems are from equilibrium. To solve this issue for Markovian jump dynamics, we show a lower bound that outperforms any other estimation of (including Bayesian approaches) in regimes lacking data due strong irreversibility state transitions. Moreover, limit complete irreversibility, our effective version thermodynamic uncertainty relation sets depends only nondissipative aspects dynamics. Such an approach is also valuable when dealing dynamics deterministic limit, such as irreversible chemical reactions. Measuring great challenge especially complex featuring multiple timescales. The authors introduce existing methods, particularly limited single

Язык: Английский

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Fluctuations in heat engines

Journal of Physics A Mathematical and Theoretical, Год журнала: 2021, Номер 55(1), С. 013001 - 013001

Опубликована: Ноя. 17, 2021

Abstract At the dawn of thermodynamics, Carnot’s constraint on efficiency heat engines stimulated formulation one most universal physical principles, second law thermodynamics. In recent years, field acquired a new twist due to enormous efforts develop and describe microscopic machines based systems as small single atoms. microscales, fluctuations are an inherent part dynamics thermodynamic variables such work fluctuate. Novel probabilistic formulations imply general symmetries limitations for fluctuating output power engines. Will their complete understanding ignite similar revolution discovery law? Here, we review known results concerning in performance To make discussion more transparent, illustrate main abstract findings exactly solvable models provide thorough theoretical introduction newcomers field.

Язык: Английский

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