Noise-Induced Phase Separation and Time Reversal Symmetry Breaking in Active Field Theories driven by persistent noise

Matteo Paoluzzi; Demian Levis; Andrea Crisanti; Ignacio Pagonabarraga

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arXiv · 2310.03423

Noise-Induced Phase Separation and Time Reversal Symmetry Breaking in Active Field Theories driven by persistent noise

Matteo Paoluzzi·Demian Levis·Andrea Crisanti·Ignacio Pagonabarraga

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Abstract

Within the Landau-Ginzburg picture of phase transitions, scalar field theories develop phase separation because of a spontaneous symmetry-breaking mechanism. This picture works in thermodynamics but also in the dynamics of phase separation. Here we show that scalar non-equilibrium field theories undergo phase separation just because of non-equilibrium fluctuations driven by a persistent noise. The mechanism is similar to what happens in Motility-Induced Phase Separation where persistent motion introduces an effective attractive force. We observe that Noise-Induced Phase Separation occurs in a region of the phase diagram where disordered field configurations would otherwise be stable at equilibrium. Measuring the local entropy production rate to quantify the time-reversal symmetry breaking, we find that such breaking is concentrated on the boundary between the two phases.

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Matteo Paoluzzi, Demian Levis, Andrea Crisanti, Ignacio Pagonabarraga. 2023-10-05. Noise-Induced Phase Separation and Time Reversal Symmetry Breaking in Active Field Theories driven by persistent noise. https://arxiv.org/abs/2310.03423

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