Symmetry Breaking and Energy Dissipation in the Mechanical Response of Amorphous Solids

Itamar Procaccia; Tuhin Samanta

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arXiv · 2505.13035

Symmetry Breaking and Energy Dissipation in the Mechanical Response of Amorphous Solids

Itamar Procaccia·Tuhin Samanta

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Abstract

Dissipation, or the loss of energy conservation, is necessarily related to symmetry breaking. Here we study the symmetry breaking that is responsible for dissipation in the mechanical response of amorphous solids to quasi-static strains. To this aim we consider carefully just one cycle of strain, to reveal the source of dissipation. In general the response can be conservative or dissipative, with a sharp transition between these options as a function of preparation parameters, accompanied by translation and rotational symmetry breaking and the onset of screening. We choose an example for which the mesoscopic theory can be solved exactly, and the microscopic physics can be revealed by numerical simulations. The mechanism of energy dissipation (when it exists) is explored in detail, showing that in this case it is due to the breaking of rotational symmetry.

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Itamar Procaccia, Tuhin Samanta. 2025-05-19. Symmetry Breaking and Energy Dissipation in the Mechanical Response of Amorphous Solids. https://arxiv.org/abs/2505.13035

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