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arXiv · 2508.17370

A Note on Non-Hydrodynamic Solutions of Kinetic Systems

Florian Kogelbauer·Ilya Karlin
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Abstract

We show that the one-dimensional three-component Grad system admits solutions that violate the Chapman--Enskog scaling in Knudsen number. In particular, there exist solutions that do not converge to the analogues of the Euler and Navier--Stokes equations for vanishing Knudsen number. These non-hydrodynamic solutions correspond to a fast spectral manifold in kinetic phase space.

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Florian Kogelbauer, Ilya Karlin. 2025-08-24. A Note on Non-Hydrodynamic Solutions of Kinetic Systems. https://arxiv.org/abs/2508.17370

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