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Published on: October 23, 2012
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Thin-film models for an active gel
G Kitavtsev1, A Münch1, B Wagner2
1Mathematical Institute, University of Oxford, Andrew Wiles Building, Oxford OX2 6GG, UK.
Proceedings. Mathematical, Physical, and Engineering Sciences
|January 4, 2019
Summary
This study introduces a new thin-film model for active liquid crystals, extending previous theories to capture complex defect structures and dynamics in active polar gels and actin networks.
Area of Science:
- Soft Matter Physics
- Active Matter Physics
- Liquid Crystal Theory
Background:
- Active liquid crystals exhibit complex defect structures relevant to biological systems.
- Existing models like Leslie-Erickson-Parodi theory have limitations in describing these phenomena.
Purpose of the Study:
- To develop a new free-boundary model for active liquid crystals based on Beris-Edwards theory.
- To analyze defect structures and dynamics in active polar gels and thin films.
- To extend the understanding of active matter systems, particularly actin networks.
Main Methods:
- Utilized Beris-Edwards theory with a tensorial order parameter and active stress contributions.
- Derived an Eriksen model for active polar gels with a scalar order parameter.
- Applied asymptotic approximation for thin films with small aspect ratios.
- Investigated defect dynamics in bulk and at walls.
Main Results:
- Developed a novel thin-film model capturing bulk and wall defect dynamics.
- The model extends previous theoretical frameworks for active liquid crystals.
- Derived an explicit solution for an active gel in a channel, showing bidirectional flow.
Conclusions:
- The new model provides a significant advancement in understanding active liquid crystal behavior.
- It accurately describes defect structures and flow generation in active gels.
- Offers insights into phenomena like ATP-driven motion in actin networks.
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