Machine learning forecasting of active nematics.

  title={Machine learning forecasting of active nematics.},
  author={Zhengyang Zhou and Chaitanya Joshi and Ruoshi Liu and Michael M. Norton and Linnea M. Lemma and Zvonimir Dogic and Michael F. Hagan and Seth Fraden and Pengyu Hong},
  journal={Soft matter},
Active nematics are a class of far-from-equilibrium materials characterized by local orientational order of force-generating, anisotropic constitutes. Traditional methods for predicting the dynamics of active nematics rely on hydrodynamic models, which accurately describe idealized flows and many of the steady-state properties, but do not capture certain detailed dynamics of experimental active nematics. We have developed a deep learning approach that uses a Convolutional Long-Short-Term-Memory… 

Physically-informed data-driven modeling of active nematics

A continuum description is essential for understanding a variety of collective phenomena in active matter. However, building quantitative continuum models of active matter from first principles can be

Submersed micropatterned structures control active nematic flow, topology, and concentration

An easy-to-implement technique to achieve tunable, local control over active nematic films, the preeminent example of active fluids, is reported and a convenient, highly tunable method for controlling flow, topology, and composition within active films is proposed.

Competing instabilities reveal how to rationally design and control active crosslinked gels

This paper investigates the origin of two distinct instabilities in active gels of biopolymers and molecular motors, and shows how to rationally design and control active materials with targeted elasticity and activity.

Kinesin and Myosin Motors Compete to Drive Rich Multi-Phase Dynamics in Programmable Cytoskeletal Composites

Actin-microtubule composites are engineer, driven by kinesin and myosin motors and tuned by crosslinkers, that restructure into diverse morphologies from interpenetrating filamentous networks to de-mixed amorphous clusters.

Topological active matter

In this review, we summarize recent progress in understanding the role and relevance of topological excitations in a special category of systems called active matter. Active matter is a class of

Variational methods and deep Ritz method for active elastic solids.

Variational methods have been widely used in soft matter physics for both static and dynamic problems. These methods are mostly based on two variational principles: the variational principle of

Topological defects govern mesenchymal condensations, offering a morphology-based tool to predict cartilage differentiation

This work shows that swirl-pattern quantification provides a novel and powerful tool to predict efficacy of bm-MSCs for in-vitro cartilage regeneration, and suggests that swirl pattern quantification via image analysis can be used to predict differentiation outcome, in context of regenerative cell therapy.

Symmetry, Thermodynamics, and Topology in Active Matter

Mark J. Bowick, Nikta Fakhri, M. Cristina Marchetti, and Sriram Ramaswamy Kavli Institute for Theoretical Physics, University of California Santa Barbara, Santa Barbara, CA 93106, USA Department of

Learning active nematics one step at a time

The study by Colen et al. (2) applies neural networks as an analysis tool for active-nematic systems, illustrating how these new approaches can provide experimental physicists with better tools to analyze their data.



Machine learning active-nematic hydrodynamics

Active nematics is used to demonstrate that neural networks can map out the spatiotemporal variation of multiple hydrodynamic parameters and forecast the chaotic dynamics of these systems, paving the way for artificial-intelligence characterization and control of coupled chaotic fields in diverse physical and biological systems, even in the absence of knowledge of the underlying dynamics.

Orientational order of motile defects in active nematics.

By tracking thousands of defects over centimetre-scale distances in microtubule-based active nematics, this work identifies a non-equilibrium phase characterized by a system-spanning orientational order of defects that persists over hours despite defect lifetimes of only seconds.

Statistical properties of autonomous flows in 2D active nematics.

The dynamics of a tunable 2D active nematic liquid crystal composed of microtubules and kinesin motors confined to an oil-water interface are studied and it is found that the vortex areas comprising the chaotic flows are exponentially distributed, which allows the characteristic system length scale.

Dynamic structure of active nematic shells

A theoretical description of nematics, coupled to the relevant hydrodynamic equations, is presented here to explain the dynamics of active nematic shells.

Topological structure dynamics revealing collective evolution in active nematics

It is revealed, through a simple model for active nematics using self-driven hard elliptic rods, that the excitation, annihilation and transportation of topological defects differ markedly from those in non-active media.

Correlation lengths in hydrodynamic models of active nematics.

In both models, the chaotic spatio-temporal dynamics in the regime of fully developed active turbulence is controlled by a single active scale determined by the balance of active and elastic stresses, regardless of whether the active stress is extensile or contractile in nature.

The interplay between activity and filament flexibility determines the emergent properties of active nematics.

A large-scale simulation study of a particle-based computational model that explicitly incorporates filament semiflexibility is described, finding that energy injected into the system at the particle scale preferentially excites bend deformations, reducing the apparent filament bend modulus.

Excitable patterns in active nematics.

It is shown that the interplay between nonuniform nematic order, activity, and flow results in spatially modulated relaxation oscillations, similar to those seen in excitable media.

Active nematics

The authors review the subfield of active nematics and provide a comparison between theoretical findings and the corresponding experimental realisations and focus primarily on microtubule–kinesin mixtures and the hydrodynamic theories that describe their properties.

Tunable structure and dynamics of active liquid crystals

It is suggested that it should be possible to tune internal stresses in active nematic systems with the goal of designing out-of-equilibrium structures with engineered dynamic responses.