Many-Body Chaos in Thermalized Fluids

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