Growth of complex dendritic fingers at the interface air and a viscous fluid in narrow gap between two parallel plates is an archetypical problem pattern formation. We find surprisingly effective means suppressing this instability by replacing one with elastic membrane. The resulting fluid-structure interaction fundamentally alters interfacial patterns that develop considerably delays onset fingering. analyze dependence on parameters system present scaling arguments to explain experimentally...

Chemotaxis of enzymes in response to gradients the concentration their substrate has been widely reported recent experiments, but a basic understanding process is still lacking. Here, we develop microscopic theory for chemotaxis that valid and other small molecules. Our includes both nonspecific interactions between enzyme as well complex formation through specific binding substrate. We find two distinct mechanisms contribute chemotaxis: diffusiophoretic mechanism due new type...

The hydrodynamic flow field around a catalytically active colloid is probed using particle tracking velocimetry both in the freely swimming state and when kept stationary with an external force. Our measurements provide information about fluid velocity vicinity of surface colloid, confirm mechanism for propulsion that was proposed recently. In addition to offering unified understanding nonequilibrium interfacial transport processes at stake, our results open way thorough description...

Single-file diffusion refers to the motion of diffusive particles in narrow channels, so that they cannot bypass each other. This constraint leads subdiffusion a tagged particle, called tracer. anomalous behavior results from strong correlations arise this geometry between tracer and surrounding bath particles. Despite their importance, these bath-tracer have long remained elusive, because determination is complex many-body problem. Recently, we shown that, for several paradigmatic models...

Recent Molecular Dynamics simulations of glass-forming liquids revealed superdiffusive fluctuations associated with the position a tracer particle (TP) driven by an external force. Such anomalous response, whose mechanism remains elusive, has been observed up to now only in systems close their glass transition, suggesting that this could be one its hallmarks. Here, we show presence superdiffusion is actual fact much more general, provided system crowded and geometrically confined. We present...

Recent experiments have revealed that the diffusivity of exothermic and fast enzymes is enhanced when they are catalytically active, different physical mechanisms been explored quantified to account for this observation. We perform measurements on endothermic relatively slow enzyme aldolase, which also shows substrate-induced diffusion. propose a new paradigm, reveals diffusion coefficient model hydrodynamically coupled its environment increases significantly undergoing changes in...

We study a minimal model of active transport in crowded single-file environments which generalizes the emblematic diffusion to case when tracer particle (TP) performs either an autonomous directed motion or is biased by external force, while all other particles environment (bath) perform unbiased diffusions. derive explicit expressions, valid limit high density bath particles, full distribution P((n))(X) TP position and its cumulants, for arbitrary values bias f any time n. Our analysis...

We study the behavior of stationary velocity a driven particle in an environment mobile hard-core obstacles. Based on lattice gas model, we demonstrate analytically that drift can exhibit nonmonotonic dependence applied force, and show quantitatively such negative differential mobility (NDM), observed various physical contexts, is controlled by both density diffusion time scale Our unifies recent numerical analytical results obtained specific regimes, makes it possible to determine region...

In single-file transport particles diffuse in narrow channels while not overtaking each other. it is a fundamental model for the tracer subdiffusion observed confined systems, such as zeolites or carbon nanotubes. This anomalous behavior originates from strong bath-tracer correlations one dimension. Despite extensive effort, these remained elusive, because they involve an infinite hierarchy of equations. For symmetric exclusion process, paradigmatic diffusion, we break to unveil and solve...

Single-file transport refers to the motion of particles in a narrow channel, such that they cannot bypass each other. This constraint leads strong correlations between particles, described by correlation profiles, which measure generic observable and density at given position time. They have recently been shown play central role single-file systems. Up now, these only determined for diffusive systems hydrodynamic limit. Here, we consider model reflecting point on infinite line, with general...

We study the dynamics of a tracer particle (TP) on comb lattice populated by randomly moving hard-core particles in dense limit. first consider case where TP is constrained to move backbone only, and, limit high density particles, we present exact analytical results for cumulants position, showing subdiffusive behavior $\sim t^{3/4}$. At longer times, second regime observed, standard diffusion recovered, with surprising non dependence coefficient density. When allowed visit teeth comb, based...

We calculate the diffusion coefficient of an active tracer in a schematic crowded environment, represented as lattice gas passive particles with hardcore interactions. Starting from master equation problem, we put forward closure approximation that goes beyond trivial mean field and provides for arbitrary density crowders system. show our is accurate very wide range parameters, it correctly captures numerous nonequilibrium effects, which are signature activity In addition to determination...

Absolute negative mobility (ANM) refers to the situation where average velocity of a driven tracer is opposite direction driving force. This effect was evidenced in different models nonequilibrium transport complex environments, whose description remains effective. Here, we provide microscopic theory for this phenomenon. We show that it emerges model an active particle submitted external force and which evolves on discrete lattice populated with mobile passive crowders. Resorting decoupling...

Computing analytically the $n$-point density correlations in systems of interacting particles is a long-standing problem statistical physics, with broad range applications, from interpretation scattering experiments simple liquids, to quantitative description slow and cooperative dynamics glass formers. For Brownian particles, i.e. overdamped Langevin dynamics, microscopic obeys stochastic evolution equation, known as Dean-Kawasaki equation. In spite importance this its complexity makes it...

Biomolecular condensates play a central role in the spatial organization of living matter. Their formation is now well understood as form liquid-liquid phase separation that occurs very far from equilibrium. For instance, they can be modeled active droplets, where combination molecular interactions and chemical reactions result microphase separation. However, so far, models chemically droplets are spatially continuous deterministic. Therefore, relationship between microscopic parameters some...

The effect of conformational fluctuations modular macromolecules, such as enzymes, on their diffusion properties is addressed using a simple generic model an asymmetric dumbbell made two hydrodynamically coupled subunits. It shown that equilibrium can lead to interplay between the internal and external degrees freedom give rise negative contributions overall coefficient. Considering this enzyme explores mechanochemical cycle, we show how substrate binding unbinding affects its fluctuations,...

We study analytically the dynamics and micro-structural changes of a host medium caused by driven tracer particle moving in confined, quiescent molecular crowding environment. Imitating typical settings active micro-rheology experiments, we consider here minimal model comprising geometrically confined lattice system -- two-dimensional strip-like or three-dimensional capillary-like populated two types hard-core particles with stochastic constant external force bath completely at random....

Single-file diffusion refers to the motion in narrow channels of particles which cannot bypass each other, and leads tracer subdiffusion. Most approaches this celebrated many-body problem were restricted description only. Here, we go beyond standard by introducing providing analytical results for generalized correlation profiles (GCPs) frame tracer. In addition controlling statistical properties tracer, these quantities fully characterize correlations between position bath density....

Abstract Single-file transport, which corresponds to the diffusion of particles that cannot overtake each other in narrow channels, is an important topic out-of-equilibrium statistical physics. Various microscopic models single-file systems have been considered, such as simple exclusion process, has reached status a paradigmatic model. Several different shown be related by duality relation, holds either microscopically or only hydrodynamic limit large time and distances. Here, we show that,...

We study the diffusion of a tracer particle driven out equilibrium by an external force and traveling in dense environment arbitrary density. The system evolves on discrete lattice its stochastic dynamics is described master equation. Relying decoupling approximation that goes beyond naive mean-field treatment problem, we calculate fluctuations position around mean value dimension, with different boundary conditions. reveal intrinsically nonequilibrium effects, such as enhanced diffusivity...

Tracer dynamics in the symmetric exclusion process (SEP), where hard-core particles diffuse on an infinite one-dimensional lattice, is a paradigmatic model of anomalous diffusion. While equilibrium situation has received lot attention, case tracer driven by external force, which provides minimal nonequilibrium transport confined crowded environments, remains largely unexplored. Indeed, only available analytical results concern means both position and lattice occupation numbers its frame...

We summarise different results on the diffusion of a tracer particle in lattice gases hard-core particles with stochastic dynamics, which are confined to narrow channels-single-files, comb-like structures and quasi-one-dimensional channels width equal several diameters. show that such geometries surprisingly rich, sometimes even counter-intuitive, behaviour emerges, is absent unbounded systems. This well-documented for anomalous single-files. Less known dynamics crowded branching...

Abstract We study the dynamics of a biased intruder (BI) pulled by constant force F through dense molecular crowding environment modelled as lattice gas unbiased, randomly moving hard-core particles. Going beyond usual analysis force–velocity relation (FVR), we focus on behaviour higher moments BI vector displacement R n at time (the FVR is just first moment) in leading order density ρ 0 vacancies (O(ρ )). prove that infinite 2D systems probability distribution P ( ) converges to Gaussian →...