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Related papers: Dynamical patterns in active nematics on a sphere

200 papers

We report on the emergence of stable self-propelled bound defects in monolayers of active nematics, which form virtual full-integer topological defects in the form of vortices and asters. Through numerical simulations and analytical…

Soft Condensed Matter · Physics 2020-10-26 Kristian Thijssen , Amin Doostmohammadi

We introduce a minimal model for a collection of self-propelled apolar active particles, also called as `active nematic', on a two-dimensional substrate and study the order-disorder transition with the variation of density. The particles…

Statistical Mechanics · Physics 2015-09-18 Rakesh Das , Manoranjan Kumar , Shradha Mishra

Active nematic fluids confined in narrow channels generate spontaneous flows when the activity is sufficiently intense. Recently, it was shown that if the molecular anchoring at the channel walls is conflicting flows are initiated even in…

Soft Condensed Matter · Physics 2021-11-02 C. Rorai , F. Toschi , I. Pagonabarraga

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

We construct the equations of motion for the coupled dynamics of order parameter and concentration for the nematic phase of driven particles on a solid surface, and show that they imply (i) giant number fluctuations, with a standard…

Soft Condensed Matter · Physics 2009-11-07 Sriram Ramaswamy , R. Aditi Simha , John Toner

Active nematics are microscopically driven liquid crystals that exhibit dynamical steady states characterized by the creation and annihilation of topological defects. Motivated by experimental realizations of such systems made of biopolymer…

Soft Condensed Matter · Physics 2018-09-05 Abhijeet Joshi , Elias Putzig , Aparna Baskaran , Michael Hagan

In active matter systems, deformable boundaries provide a mechanism to organize internal active stresses and perform work on the external environment. To study a minimal model of such a system, we perform particle-based simulations of an…

Soft Condensed Matter · Physics 2022-01-05 Matthew S. E. Peterson , Aparna Baskaran , Michael F. Hagan

Using a minimal continuum model, we investigate the interplay between circular confinement and substrate friction in active nematics. Upon increasing the friction from low to high, we observe a dynamical phase transition from a circulating…

Soft Condensed Matter · Physics 2023-10-27 Cody D. Schimming , C. J. O. Reichhardt , C. Reichhardt

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

The topological properties of many materials are central to their behavior, with the dynamics of topological defects being particularly important to intrinsically out-of-equilibrium, active materials. In this paper, local manipulation of…

Soft Condensed Matter · Physics 2019-11-01 David P. Rivas , Tyler N. Shendruk , Robert R. Henry , Daniel H. Reich , Robert L. Leheny

Starting from a three-dimensional description of an active nematic layer, we employ an asymptotic theory to derive a series of low-dimensional continuum models that capture the coupled dynamics of flat and curved films, including variations…

Soft Condensed Matter · Physics 2025-06-23 Mehrana R. Nejad , L. Mahadevan

Mechanochemical processes on surfaces such as the cellular cortex or epithelial sheets, play a key role in determining patterns and shape changes of biological systems. To understand the complex interplay of hydrodynamics and material flows…

Soft Condensed Matter · Physics 2023-05-04 Lucas D. Wittwer , Sebastian Aland

Active nematics are an important new paradigm in soft condensed matter systems. They consist of rod-like components with an internal driving force pushing them out of equilibrium. The resulting fluid motion exhibits chaotic advection, in…

The hydrodynamic theory of active nematics has been often used to describe the spatio-temporal dynamics of cell flows and motile topological defects within soft confluent tissues. Those theories, however, often rely on the assumption that…

Soft Condensed Matter · Physics 2023-08-15 Ioannis Hadjifrangiskou , Liam J. Ruske , Julia M. Yeomans

Cell monolayers are a central model system to tissue biophysics. In vivo, epithelial tissues are curved on the scale of microns, and curvature's role in the onset of spontaneous tissue flows is still not well-understood. Here, we present a…

Biological Physics · Physics 2022-09-21 Samuel Bell , Shao-Zhen Lin , Jean-François Rupprecht , Jacques Prost

Active matter locally converts chemical energy into mechanical work and, for this reason, it provides new mechanisms of pattern formation. In particular, active gels made of protein motors and filaments are far-from-equilibrium systems that…

Confinement can be used to systematically tame turbulent dynamics occurring in active fluids. Although periodic channels are the simplest geometries to study confinement numerically, the corresponding experimental realizations require…

Soft Condensed Matter · Physics 2023-04-12 Chaitanya Joshi , Zahra Zarei , Michael M. Norton , Seth Fraden , Aparna Baskaran , Michael F. Hagan

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 self-propulsion of +1/2 topological defects is a hallmark of active nematic fluids, where the defects are advected by the flow field they themselves generate. In this paper we propose a minimal model for defect self-propulsion in a…

Soft Condensed Matter · Physics 2025-08-08 Fridtjof Brauns , Myles O'Leary , Arthur Hernandez , Mark J. Bowick , M. Cristina Marchetti

We examine the dynamics of a compressible active nematic liquid crystal on a frictional substrate. When frictional damping dominates over viscous dissipation, we eliminate flow in favor of active stresses to obtain a minimal dynamical model…

Soft Condensed Matter · Physics 2016-11-07 Pragya Srivastava , Prashant Mishra , M. Cristina Marchetti