Violation of the fluctuation dissipation theorem during domain growth in the long-range Ising model
Phys. Rev. E 114, 014109 – Published 6 July, 2026
DOI: https://doi.org/10.1103/s6f3-zcd6
Abstract
The celebrated fluctuation dissipation theorem (FDT) does not apply to nonequilibrium systems. In this context, Cugliandolo and Kurchan [Phys. Rev. Lett. 71, 173 (1993)] introduced a generalized FDT which interprets the nonequilibrium evolution as a composition of time sectors corresponding to different effective temperatures. We use this framework to study domain growth in the long-range Ising model with nonconserved kinetics (Glauber spin flip) and conserved kinetics (Kawasaki spin exchange). We study the dynamical scaling and superuniversal scaling of various two-time quantities, e.g., autocorrelation function, response function, effective temperature, etc. In particular, we investigate how the interaction range and conservation laws affect these characteristic features of domain growth.