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Related papers: Instabilities and Topological Defects in Active Ne…

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Active matter, encompassing natural systems, converts surrounding energy to sustain autonomous motion, exhibiting unique non-equilibrium behaviors such as active turbulence and phase separation. In this study, we develop a continuum…

Soft Condensed Matter · Physics 2026-05-06 Sohail Ahmed , Zixiang Lin , Zijie Qu

The growing interest in active nematics and the emerging evidence of the relevance of topological defects in biology asks for reliable data analysis tools to identify, classify and track such defects in simulation and microscopy data. We…

Soft Condensed Matter · Physics 2020-02-10 Dennis Wenzel , Michael Nestler , Sebastian Reuther , Maximilian Simon , Axel Voigt

We consider a continuum model of active viscoelastic matter, whereby an active nematic liquid-crystal is coupled to a minimal model of polymer dynamics with a viscoelastic relaxation time $\tau_C$. To explore the resulting interplay between…

Soft Condensed Matter · Physics 2016-03-30 E. J. Hemingway , M. E. Cates , S. M. Fielding

We study the spatiotemporal patterns that emerge when an active nematic film is topologically constraint. These topological constraints allow to control the non-equilibrium dynamics of the active system. We consider ellipsoidal shapes for…

Soft Condensed Matter · Physics 2017-03-13 Francesco Alaimo , Christian Köhler , Axel Voigt

We establish how active stress globally affects the morphology of disclination lines of a three dimensional active nematic liquid crystal under chaotic flow. Thanks to a defect detection algorithm based on the local nematic orientation, we…

Soft Condensed Matter · Physics 2025-06-30 Pasquale Digregorio , Cecilia Rorai , Ignacio Pagonabarraga , Federico Toschi

We study dry, dense active nematics at both particle and continuous levels. Specifically, extending the Boltzmann-Ginzburg-Landau approach, we derive well-behaved hydrodynamic equations from a Vicsek-style model with nematic alignment and…

Soft Condensed Matter · Physics 2019-12-20 Aurelio Patelli , Ilyas Djafer-Cherif , Igor S. Aranson , Eric Bertin , Hugues Chaté

The negative effective magnetic pressure instability operates on scales encompassing many turbulent eddies and is here discussed in connection with the formation of active regions near the surface layers of the Sun. This instability is…

Solar and Stellar Astrophysics · Physics 2013-09-10 Koen Kemel , Axel Brandenburg , Nathan Kleeorin , Dhrubaditya Mitra , Igor Rogachevskii

We propose an agent-based model of active flexible rods. Inspired by cytoskeletal flows, we introduce activity by an internal flow that contributes to the dissipative forces. The active force between our agents is central and reciprocal,…

Soft Condensed Matter · Physics 2026-03-06 Mathieu Dedenon , Carles Blanch-Mercader , Karsten Kruse , Jens Elgeti

A wide range of living and artificial active matter exists in close contact with substrates and under strong confinement, where in addition to dipolar active stresses, quadrupolar active stresses can become important. Here, we numerically…

Soft Condensed Matter · Physics 2024-04-23 Salik A. Sultan , Mehrana R. Nejad , Amin Doostmohammadi

Topological defects are at the root of the large-scale organization of liquid crystals. In two-dimensional active nematics, two classes of topological defects of charges $\pm 1/2$ are known to play a major role due to active stresses.…

Soft Condensed Matter · Physics 2022-04-08 Louis Brézin , Thomas Risler , Jean-François Joanny

Direct numerical simulation of the strongly nonlinear stages of instability development for a non-conducting liquid with a charged free surface in a normal electric field is performed. It is demonstrated that two main stages of the…

Fluid Dynamics · Physics 2026-01-28 N. M. Zubarev , E. A. Kochurin

Active matter often simultaneously exhibits different kinds of orientational order and, in many cases of biological interest, undergoes continuous material renewal. In renewing nematopolar fluids we find stable topological strings,…

Soft Condensed Matter · Physics 2026-01-27 Alberto Dinelli , Ludovic Dumoulin , Karsten Kruse

Instabilities of fluid-fluid interfaces are ubiquitous in passive soft matter. Adding activity to the interface or either fluid can dramatically change the stability of the interface. Using experiment and theory, we investigate the…

Soft Condensed Matter · Physics 2026-02-04 Bennett C. Sessa , Federico Cao , Robert A. Pelcovits , Thomas R. Powers , Guillaume Duclos

Confined active nematics exhibit rich dynamical behavior, including spontaneous flows, periodic defect dynamics, and chaotic `active turbulence'. Here, we study these phenomena using the framework of Exact Coherent Structures, which has…

Soft Condensed Matter · Physics 2022-01-26 Caleb G. Wagner , Michael M. Norton , Jae Sung Park , Piyush Grover

Active fluids, such as cytoskeletal filaments, bacterial colonies and epithelial cell layers, exhibit distinctive orientational coherence, often characterized by nematic order and topological defects. By contrast, little is known about…

Soft Condensed Matter · Physics 2021-04-07 Mattia Serra , Linnea Lemma , Luca Giomi , Zvonimir Dogic , L. Mahadevan

We investigate the effects of extrinsic curvature on the turbulent behavior of a 2D active nematic confined to the surface of a cylinder. The surface of a cylinder has no intrinsic curvatrue and only extrinsic curvature. A nematic field…

Soft Condensed Matter · Physics 2020-08-26 D. J. G. Pearce

The persistent dynamics in systems out of equilibrium, particularly those characterized by annihilation and creation of topological defects, is known to involve complicated spatiotemporal processes and is deemed difficult to control. Here…

Soft Condensed Matter · Physics 2022-11-22 Zhi-Feng Huang , Hartmut Löwen , Axel Voigt

We propose a simple deterministic dynamic equation and reveal the mechanism of large-scale endless evolvement of spatial density inhomogeneity in active nematic. We determine the phase regions analytically. The interplay of density,…

Statistical Mechanics · Physics 2010-11-25 Xia-qing Shi , Yu-qiang Ma

The conditions under which stable evolution of two nonlinear interacting waves are derived within the context of nematic crystals. Two cases are considered: plane waves and solitons. In the first case, the modulation instability analysis…

Pattern Formation and Solitons · Physics 2016-10-12 Theodoros P. Horikis

When a nematic liquid crystal is confined in a porous medium with strong anchoring conditions, topological defects, called disclinations, are stably formed with numerous possible configurations. Since the energy barriers between them are…

Soft Condensed Matter · Physics 2015-06-12 Takeaki Araki