Flat or crumpled: States of active symmetric membranes
Year: 2025
Type: article
Abstract: We set up and study the hydrodynamic theory for inversion-symmetric active fluid and tethered membranes. For some choices of the activity parameter, such membranes are stable and described by linear hydrodynamic equations, which are exact in the asymptotic long wavelength limit, giving stable flat phases with translational quasi-long-range orders. For other choices of the activity parameter, the system is linearly unstable in the long wavelength limit, implying crumpling, or has intermediate wave-vector instabilities, suggesting patterns. We argue that in such an active membrane thermal noises dominate over any active noises, and use those to calculate the correlation functions of membrane conformation fluctuations in the stable case, and the associated correlation functions of the embedding bulk flow velocities. Our work identifies a hitherto unknown activity-induced route, distinct from the well-known thermal crumpling of equilibrium fluid membranes, to destabilize a membrane.
Source: Physical review. E
DOI: 10.1103/btbj-wsy5
Authors: Sudip Mukherjee, Abhik Basu
Language: English
Topic: Micro and Nano Robotics
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Funder: Alexander von Humboldt-Stiftung
OpenAlex ID: W4411274384