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تسجيل مستخدم جديدIdealized Hydrodynamics
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Transport is one of the most important physical processes in all energy and length scales. The non-interacting Boltzmann equation and the hydrodynamic equations respectively describe two opposite limits of transport. Here we present an unexpected mathematical connection between these two limits, named textit{idealized hydrodynamics}, which refers to the situation where the solution to the hydrodynamic equations of an interacting system can be exactly constructed from the solutions of a non-interacting Boltzmann equation. We analytically provide three examples of such idealized hydrodynamics. These examples respectively recover the dark soliton solution in a one-dimensional superfluid, generalize fermionization to the hydrodynamics of strongly interacting systems, and determine specific initial conditions for perfect density oscillations in a harmonic trap. They can be used, for instance, to explain a recent puzzling experimental observation in ultracold atomic gases by the Paris group, and to make further predictions for future experiments. We envision that extensive examples of such idealized hydrodynamics can be found by systematical numerical search, which can find broad applications in different problems in various subfields of physics.
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