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Elasticity tunes mechanical stress localization around active topological defects
Lasse Bonn1, Aleksandra Ardaševa1, Amin Doostmohammadi1
1Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, Copenhagen, Denmark. doostmohammadi@nbi.ku.dk.
Soft Matter
|December 5, 2023
Summary
Mechanical stresses near topological defects are controlled by material properties. Changing elastic constants can flip tension and compression regions, offering a simple way to switch active matter dynamics.
Area of Science:
- Physics
- Materials Science
- Biophysics
Background:
- Mechanical stresses are linked to biological functions.
- Topological defects are sites of localized mechanical stress in biological systems.
Purpose of the Study:
- To investigate how mechanical stress localization around topological defects is controlled.
- To explore stress patterns, extent, and intensity around topological defects using continuum simulations.
Main Methods:
- Continuum simulations of nonequilibrium, fluctuating, and active nematics.
- Analysis of stress localization patterns, extent, and intensity around topological defects.
- Varying orientational elasticity and elastic anisotropy of the material.
Main Results:
- Increasing orientational elasticity changes stress patterns from dipole to monopole.
- Elastic anisotropy alters stress extent and intensity, favoring tension or compression.
- Elastic constant tunes effects of fluctuations and active stress, flipping tension-compression regions.
Conclusions:
- Material properties, specifically elastic constants, can control stress localization around topological defects.
- Flipping tension-compression regions by altering elastic constants offers a simple method to switch active matter dynamics.
- Findings encourage exploring material property tuning for active biological materials.
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