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Related papers: Dynamical patterns in active nematics on a sphere

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We have studied the collective motion of polar active particles confined to ellipsoidal surfaces. The geometric constraints lead to the formation of vortices that encircle surface points of constant curvature (umbilics). We have found that…

Soft Condensed Matter · Physics 2017-07-04 Sebastian Ehrig , Jonathan Ferracci , Richard Weinkamer , John W. C. Dunlop

Active nematic fluids exhibit complex dynamics in both bulk and in simple confining geometries. However, complex confining geometries could have substantial impact on active spontaneous flows. Using multiparticle collision dynamics…

Soft Condensed Matter · Physics 2025-01-16 Jaideep P. Vaidya , Tyler N. Shendruk , Sumesh P. Thampi

We show that the dominant mode of alignment plays an important role in dry active nematics,leading to two dynamical sub-classes defined by the nature of the instability of the nematic bands that characterize, in these systems, the…

Soft Condensed Matter · Physics 2019-01-16 Li-bing Cai , Hugues Chaté , Yu-qiang Ma , Xia-qing Shi

Many biological systems consist of self-motile and passive agents both of which contribute to overall functionality. However, there are very few studies of the properties of such mixtures. Here we formulate a model for mixtures of…

Soft Condensed Matter · Physics 2015-05-25 Denis F. Hinz , Alexander Panchenko , Tae-Yeon Kim , Eliot Fried

I put forward a continuum theory for active nematic gels, defined as fluids or suspensions of orientable rodlike objects endowed with active dynamics, that is based on symmetry arguments and compatibility with thermodynamics. The starting…

Soft Condensed Matter · Physics 2017-11-15 Stefano S Turzi

Curvature plays a central organizational role in active polymer dynamics. Using large-scale Langevin-dynamics simulations, we study active semiflexible filaments confined to smooth curved surfaces and map how curvature, bending rigidity,…

Soft Condensed Matter · Physics 2026-02-18 Giulia Janzen , Euan D. Mackay , Rastko Sknepnek , D. A. Matoz-Fernandez

In vitro reconstituted active systems, such as the ATP-driven microtubule bundle suspension developed by the Dogic group, provide a fertile testing ground for elucidating the phenomenology of active liquid crystalline states. Controlling…

Soft Condensed Matter · Physics 2017-01-04 Pau Guillamat , Jordi Ignés-Mullol , Suraj Shankar , M. Cristina Marchetti , Francesc Sagués

Curvature plays a central role in the proper function of many biological processes. With active matter being a standard framework for understanding many aspects of the physics of life, it is natural to ask what effect curvature has on the…

Soft Condensed Matter · Physics 2026-01-27 Euan D. Mackay , Giulia Janzen , D. A. Matoz Fernandez , Rastko Sknepnek

Models for fluid deformable surfaces provide valid theories to describe the dynamics of thin fluidic sheets of soft materials. To use such models in morphogenesis and development requires to incorporate active forces. We consider active…

Mathematical Physics · Physics 2024-08-20 Maik Porrmann , Axel Voigt

Motor proteins drive persistent motion and self-organisation of cytoskeletal filaments. However, state-of-the-art microscopy techniques and continuum modelling approaches focus on large length and time scales. Here, we perform…

Soft Condensed Matter · Physics 2024-06-03 Gerrit Vliegenthart , Arvind Ravichandran , Marisol Ripoll , Thorsten Auth , Gerhard Gompper

The coupling of active, self-motile particles to topological constraints can give rise to novel non-equilibrium dynamical patterns that lack any passive counterpart. Here we study the behavior of self-propelled rods confined to a compact…

Statistical Mechanics · Physics 2018-08-21 Liesbeth M. C. Janssen , Andreas Kaiser , Hartmut Löwen

Shape transformations of epithelial tissues in three dimensions, which are crucial for embryonic development or in vitro organoid growth, can result from active forces generated within the cytoskeleton of the epithelial cells. How the…

Biological Physics · Physics 2024-12-23 Diana Khoromskaia , Guillaume Salbreux

In nature interactions between biopolymers and motor proteins give rise to biologically essential emergent behaviours. Besides cytoskeleton mechanics, active nematics arise from such interactions. Here we present a study on 3D active…

Topological defects are distinctive signatures of liquid crystals. They profoundly affect the viscoelastic behavior of the fluid by constraining the orientational structure in a way that inevitably requires global changes not achievable…

Soft Condensed Matter · Physics 2015-06-19 Luca Giomi , Mark J. Bowick , Prashant Mishra , Rastko Sknepnek , M. Cristina Marchetti

The spontaneous emergence of collective flows is a generic property of active fluids and often leads to chaotic flow patterns characterised by swirls, jets, and topological disclinations in their orientation field. However, the ability to…

Soft Condensed Matter · Physics 2017-03-07 Tyler N. Shendruk , Amin Doostmohammadi , Kristian Thijssen , Julia M. Yeomans

The emergence of macroscopic order and patterns is a central paradigm in systems of (self-)propelled agents, and a key component in the structuring of many biological systems.The relationships between the ordering process and the underlying…

Soft Condensed Matter · Physics 2020-12-02 Jonas Denk , Erwin Frey

In two dimensional nematics, topological defects are point like singularities with both a charge and a phase. We study topological defects within curved nematic textures on the surface of a cylinder. This allows us to isolate the effect of…

Soft Condensed Matter · Physics 2022-05-10 Daniel J. G. Pearce

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…

Soft Condensed Matter · Physics 2019-02-06 Romain Mueller , Julia Yeomans , Amin Doostmohammadi

Recent experiments on active materials, such as dense bacterial suspensions and microtubule-kinesin motor mixtures, show a promising potential for achieving self-sustained flows. However, to develop active microfluidics it is necessary to…

Soft Condensed Matter · Physics 2019-01-23 Santhan Chandragiri , Amin Doostmohammadi , Julia M Yeomans , Sumesh P Thampi

We introduce a lattice model for active nematic composed of self-propelled apolar particles,study its different ordering states in the density-temperature parameter space, and compare with the corresponding equilibrium model. The active…

Soft Condensed Matter · Physics 2017-07-26 Rakesh Das , Manoranjan Kumar , Shradha Mishra