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arXiv · 2511.03123

Surface wakes on ultra-soft solids

Aditi Chakrabarti·Divya Jaganathan·Robert Haussman·L. Mahadevan
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Abstract

We explore the dynamical response of the free surface of an ultra-soft solid driven by a localized moving pressure disturbance. Experiments reveal a steady V-shaped wake analogous to a surface Mach wedge. A simple geometric argument provides a qualitative explanation consistent with observations. A theoretical framework combining elastodynamic, capillary, and gravitational effects yields a generalized dispersion relation that smoothly interpolates between Kelvin's theory of liquid interface wakes and Rayleigh's theory of elastic surface waves. Together, our experiments and theory reveal the existence of a soft wake regime that bridges fluid and solid surface wave physics, offering new routes for probing the dynamics of soft surfaces.

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Aditi Chakrabarti, Divya Jaganathan, Robert Haussman, L. Mahadevan. 2025-11-05. Surface wakes on ultra-soft solids. https://arxiv.org/abs/2511.03123

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