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arXiv · 1811.12540

Theory of diffusive fluctuations

Xinyi Chen-Lin·Luca V. Delacrétaz·Sean A. Hartnoll
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Abstract

The recently developed effective field theory of fluctuations around thermal equilibrium is used to compute late-time correlation functions of conserved densities. Specializing to systems with a single conservation law, we find that the diffusive pole is shifted in the presence of non-linear hydrodynamic self-interactions, and that the density-density Green's function acquires a branch point half way to the diffusive pole, at frequency $\omega= -\frac{i}{2}Dk^2$. We discuss the relevance of diffusive fluctuations for strongly correlated transport in condensed matter and cold atomic systems.

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Xinyi Chen-Lin, Luca V. Delacrétaz, Sean A. Hartnoll. 2018-11-29. Theory of diffusive fluctuations. https://doi.org/10.1103/physrevlett.122.091602

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