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Published on: September 9, 2022
Statics and diffusive dynamics of surfaces driven by p-atic topological defects
Farzan Vafa1, L Mahadevan2,3
1Center of Mathematical Sciences and Applications, Harvard University, Cambridge, MA 02138, USA. fvafa@cmsa.fas.harvard.edu.
This study models surface shaping using topological defects, showing positive defects create cones and predicting semi-cone angles. The research reveals deformed lemon shapes in membranes, with implications for epithelial morphogenesis and pollen grain shape transitions.
Area of Science:
- Mathematical Biology
- Soft Matter Physics
- Surface Geometry
Background:
- Epithelial morphogenesis involves complex surface shaping processes.
- Topological defects play a crucial role in biological and physical systems.
- Understanding the interplay between intrinsic and extrinsic geometry is key.
Purpose of the Study:
- To develop a minimal model for surface shaping driven by p-atic topological defects.
- To investigate the dynamic generation and evolution of conical shapes from defects.
- To predict the final shape and geometric properties of membranes with embedded polar order.
Main Methods:
- Utilized a minimal mathematical model for surface dynamics.
- Analyzed the behavior of positive and negative topological defects.
- Exploited the coupling between extrinsic and intrinsic geometry for axisymmetric surfaces.
Main Results:
- Positive (negative) defects dynamically generate (hyperbolic) cones with diffusive shape evolution.
- A defect of charge +1/p predicts a final semi-cone angle β satisfying a specific inequality.
- Stationary membranes with negligible bending modulus and polar order form deformed lemon shapes with antipodal defects.
Conclusions:
- The study provides a theoretical framework for defect-driven surface morphogenesis.
- Results offer insights into the formation of conical and lemon-like surface geometries.
- Findings may extend to shape transitions in other closed spheroidal surfaces, like pollen grains.
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