How to deform an egg yolk? On the Study of Soft Matter Deformation in a Liquid Environment

TL;DR

This study investigates how soft matter like egg yolks deforms under external impacts in a liquid, revealing that rotational impacts cause significant deformation due to centrifugal forces and membrane shape effects.

Contribution

It provides the first experimental and theoretical analysis of soft capsule deformation in liquids, highlighting the importance of rotational impacts and membrane dynamics.

Findings

Soft matter is insensitive to translational impacts.

Rotational impacts cause significant deformation.

Centrifugal force and membrane shape are key factors.

Abstract

In this paper, we report a novel experimental and theoretical study to examine the response of a soft capsule bathed in a liquid environment to sudden external impacts. Taking an egg yolk as an example, we found that the soft matter is not sensitive to translational impacts, but is very sensitive to rotational, especially decelerating-rotational impacts, during which the centrifugal force and the shape of the membrane together play a critical role causing the deformation of the soft object. This finding, as the first study of its kind, reveals the fundamental physics behind the motion and deformation of a membrane-bound soft object, e.g., egg yolk, cells, soft brain matter, etc., in response to external impacts.