Fluctuation dissipation relations for active field theories

作者：Martin Kjøllesdal Johnsrud, Ramin Golestanian · 发表于：Physical Review Research · 年份：2025 · DOI：10.1103/xx4z-lj5c · 被引用次数：7 · 研究领域：Advanced Thermodynamics and Statistical Mechanics、Micro and Nano Robotics、Material Dynamics and Properties

Breakdown of time-reversal symmetry is a defining property of nonequilibrium systems, such as active matter, which is composed of units that consume energy. We employ a formalism that allows us to derive a class of identities associated with the time-reversal transformation in nonequilibrium field theories, in the spirit of Ward-Takahashi identities. We present a generalization of the fluctuation dissipation theorem valid for active systems as a particular realization of such an identity, and consider its implications and applications for a range of active field theories. The field theoretical toolbox developed here helps to quantify the degree of nonequilibrium activity of complex systems exhibiting collective behavior.