Active matter ≈ Active matter
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Shape-programmable magnetic soft matter Open
Significance At small scales, shape-programmable magnetic materials have significant potential to achieve mechanical functionalities that are unattainable by traditional miniature machines. Unfortunately, these materials have only been pro…
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How Far from Equilibrium Is Active Matter? Open
Active matter systems are driven out of thermal equilibrium by a lack of generalized Stokes-Einstein relation between injection and dissipation of energy at the microscopic scale. We consider such a system of interacting particles, propell…
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Materials learning from life: concepts for active, adaptive and autonomous molecular systems Open
A broad overview of functional aspects in biological and synthetic out-of-equilibrium systems.
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The 2020 motile active matter roadmap Open
Activity and autonomous motion are fundamental in living and engineering systems. This has stimulated the new field of ‘active matter’ in recent years, which focuses on the physical aspects of propulsion mechanisms, and on motility-induced…
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Phoretic Self-Propulsion Open
It is well-known that micro- and nanoparticles can move by phoretic effects in response to externally imposed gradients of scalar quantities such as chemical concentration or electric potential. A class of active colloids can propel themse…
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Active matter Open
The study of systems with sustained energy uptake and dissipation at the\nscale of the constituent particles is an area of central interest in\nnonequilibrium statistical physics. Identifying such systems as a distinct\ncategory -- Active …
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Rheology of Active Fluids Open
An active fluid denotes a viscous suspension of particles, cells, or macromolecules able to convert chemical energy into mechanical work by generating stresses on the microscale. By virtue of this internal energy conversion, these systems …
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Dry Aligning Dilute Active Matter Open
Active matter physics is about systems in which energy is dissipated at some local level to produce work. This is a generic situation, particularly in the living world but not only. What is at stake is the understanding of the fascinating,…
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Depinning and nonequilibrium dynamic phases of particle assemblies driven over random and ordered substrates: a review Open
We review the depinning and nonequilibrium phases of collectively interacting particle systems driven over random or periodic substrates. This type of system is relevant to vortices in type-II superconductors, sliding charge density waves,…
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Designing Micro- and Nanoswimmers for Specific Applications Open
Self-propelled colloids have emerged as a new class of active matter over the past decade. These are micrometer sized colloidal objects that transduce free energy from their surroundings and convert it to directed motion. The self-propelle…
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Self-Propelled Rods: Insights and Perspectives for Active Matter Open
A wide range of experimental systems including gliding, swarming and swimming bacteria, in vitro motility assays, and shaken granular media are commonly described as self-propelled rods. Large ensembles of those entities display a large va…
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Ratchet Effects in Active Matter Systems Open
Ratchet effects can arise for single or collectively interacting Brownian particles on an asymmetric substrate when a net dc transport is produced by an externally applied ac driving force or by periodically flashing the substrate. Recentl…
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Active Turbulence Open
Active fluids exhibit spontaneous flows with complex spatiotemporal structure, which have been observed in bacterial suspensions, sperm cells, cytoskeletal suspensions, self-propelled colloids, and cell tissues. Despite occurring in the ab…
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Physical intelligence as a new paradigm Open
Intelligence of physical agents, such as human-made (e.g., robots, autonomous cars) and biological (e.g., animals, plants) ones, is not only enabled by their computational intelligence (CI) in their brain, but also by their physical intell…
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Inertial effects of self-propelled particles: From active Brownian to active Langevin motion Open
Active particles that are self-propelled by converting energy into mechanical motion represent an expanding research realm in physics and chemistry. For micrometer-sized particles moving in a liquid (“microswimmers”), most of the basic fea…
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Classical dynamical density functional theory: from fundamentals to applications Open
Classical dynamical density functional theory (DDFT) is one of the\ncornerstones of modern statistical mechanics. It is an extension of the highly\nsuccessful method of classical density functional theory (DFT) to\nnonequilibrium systems. …
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Irreversibility in Active Matter Systems: Fluctuation Theorem and Mutual Information Open
We consider a Brownian particle which, in addition to being in contact with a thermal bath, is driven by fluctuating forces which stem from active processes in the system, such as self-propulsion or collisions with other active particles. …
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From mechanical resilience to active material properties in biopolymer networks Open
The cells and tissues that make up our body manage contradictory mechanical demands. It is crucial for their survival to be able to withstand large mechanical loads, but it is equally crucial for them to produce forces and actively change …
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Control of active liquid crystals with a magnetic field Open
Significance Active liquid crystals are aqueous in vitro suspensions of cytoskeletal proteins that self-assemble into elongated fibers and develop sustained flows at the continuous expense of ATP. When they condense on soft interfaces, the…
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Collective Behavior of Chiral Active Matter: Pattern Formation and Enhanced Flocking Open
We generalize the Vicsek model to describe the collective behavior of polar circle swimmers with local alignment interactions. While the phase transition leading to collective motion in 2D (flocking) occurs at the same interaction to noise…
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Aggregation-fragmentation and individual dynamics of active clusters Open
A remarkable feature of active matter is the propensity to self-organize. One striking instance of this ability to generate spatial structures is the cluster phase, where clusters broadly distributed in size constantly move and evolve thro…
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Flocking ferromagnetic colloids Open
Energized by a vertical alternating magnetic field, colloidal particles roll and flock together.
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Soft Microrobots Employing Nonequilibrium Actuation via Plasmonic Heating Open
A soft microrobot composed of a microgel and driven by the light-controlled nonequilibrium dynamics of volume changes is presented. The photothermal response of the microgel, containing plasmonic gold nanorods, enables fast heating/cooling…
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Generalized thermodynamics of phase equilibria in scalar active matter Open
Motility-induced phase separation (MIPS) arises generically in fluids of self-propelled particles when interactions lead to a kinetic slowdown at high densities. Starting from a continuum description of scalar active matter akin to a gener…
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Turbulent Dynamics of Epithelial Cell Cultures Open
We investigate the large length and long time scales collective flows and structural rearrangements within in vitro human bronchial epithelial cell (HBEC) cultures. Activity-driven collective flows result in ensembles of vortices randomly …
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Large-Scale Patterns in a Minimal Cognitive Flocking Model: Incidental Leaders, Nematic Patterns, and Aggregates Open
We study a minimal cognitive flocking model, which assumes that the moving entities navigate using the available instantaneous visual information exclusively. The model consists of active particles, with no memory, that interact by a short…
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The physics of active polymers and filaments Open
Active matter agents consume internal energy or extract energy from the environment for locomotion and force generation. Already, rather generic models, such as ensembles of active Brownian particles, exhibit phenomena, which are absent at…
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Motility-Induced Temperature Difference in Coexisting Phases Open
Unlike in thermodynamic equilibrium where coexisting phases always have the same temperature, here we show that systems comprising "active" self-propelled particles can self-organize into two coexisting phases at different kinetic temperat…
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The Actin Cytoskeleton as an Active Adaptive Material Open
Actin is the main protein used by biological cells to adapt their structure and mechanics to their needs. Cellular adaptation is made possible by molecular processes that strongly depend on mechanics. The actin cytoskeleton is also an acti…
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Emergence of Active Nematic Behavior in Monolayers of Isotropic Cells Open
There is now growing evidence of the emergence and biological functionality of liquid crystal features, including nematic order and topological defects, in cellular tissues. However, how such features that intrinsically rely on particle el…