Active fluctuations induce buckling of living surfaces

Matteo Ciarchi; Andriy Goychuk; Erwin Frey

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arXiv · 2602.24272

Active fluctuations induce buckling of living surfaces

Matteo Ciarchi·Andriy Goychuk·Erwin Frey

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Abstract

Active tissues exhibit tension fluctuations that are correlated in space and time. We study a minimal overdamped surface model in which such fluctuations enter as a zero-mean, multiplicative modulation of the local surface tension. Although the deterministic elastic dynamics (tension plus bending) stabilizes the flat state for all nonzero wave numbers, we find that sufficiently persistent active fluctuations generate positive ensemble growth rates for a finite band of Fourier modes, leading to stochastic buckling with wavelength selection. A non-Markovian theory based on the Novikov--Furutsu theorem captures the instability threshold and unstable band observed in simulations.

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Matteo Ciarchi, Andriy Goychuk, Erwin Frey. 2026-02-27. Active fluctuations induce buckling of living surfaces. https://arxiv.org/abs/2602.24272

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