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Updated: Mar 13, 2026
08:37
Forming, Confining, and Observing Microtubule-Based Active Nematics
Published on: January 13, 2023
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Correlation lengths in hydrodynamic models of active nematics.
Ewan J Hemingway1, Prashant Mishra2, M Cristina Marchetti3
1Department of Physics, Durham University, Science Laboratories, South Road, Durham, DH1 3LE, UK. e.j.hemingway@durham.ac.uk.
Soft Matter
|October 11, 2016
Summary
We found a single active length scale governs active turbulence in liquid crystals, regardless of stress type. This scale, determined by active and elastic stresses, unifies understanding of nonequilibrium dynamics.
Area of Science:
- Soft Matter Physics
- Nonlinear Dynamics
- Liquid Crystal Science
Background:
- Active nematic liquid crystals exhibit complex nonequilibrium dynamics.
- Previous studies show discrepancies in understanding emergent length scales.
- Hydrodynamic models are crucial for simulating these systems.
Purpose of the Study:
- To investigate the scaling of emergent length scales with activity in active nematic liquid crystals.
- To analyze the control of chaotic spatio-temporal dynamics in active turbulence.
- To unify understanding across different theoretical models.
Main Methods:
- Utilized two established hydrodynamic models for active nematic liquid crystals.
- Examined the relationship between activity and emergent length scales.
- Performed dimensional analysis and derived a single-length scale argument.
Main Results:
- Identified a single active length scale controlling active turbulence in both models.
- This scale arises from the balance of active and elastic stresses.
- Observed consistent scaling of kinetic energy and enstrophy with activity.
Conclusions:
- The essential physics of active turbulence is robust across different models.
- A unified understanding of emergent length scales is achieved.
- The findings reconcile previous discrepancies in the literature.
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