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arXiv · 1906.00016

Many-body Chaos in Thermalised Fluids

Sugan D. Murugan·Dheeraj Kumar·Subhro Bhattacharjee·Samriddhi Sankar Ray
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Abstract

Linking thermodynamic variables like temperature $T$ and the measure of chaos, the Lyapunov exponents $\lambda$, is a question of fundamental importance in many-body systems. By using nonlinear fluid equations in one and three dimensions, we prove that in thermalised flows $\lambda \propto \sqrt{T}$, in agreement with results from frustrated spin systems. This reveals an underlying universality and provides evidence for recent conjectures on the thermal scaling of $\lambda$. We also reconcile seemingly disparate effects -- equilibration on one hand and pushing systems out-of-equilibrium on the other -- of many-body chaos by relating $\lambda$ to $T$ through the dynamical structures of the flow.

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BibTeXRIS

Sugan D. Murugan, Dheeraj Kumar, Subhro Bhattacharjee, Samriddhi Sankar Ray. 2019-05-31. Many-body Chaos in Thermalised Fluids. https://doi.org/10.1103/physrevlett.127.124501

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