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arXiv · 2501.07393

On the axially symmetric solutions to the spatially homogeneous Landau equation

Jin Woo Jang·Junha Kim
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Abstract

In this paper, we consider the spatially homogeneous Landau equation, which is a variation of the Boltzmann equation in the grazing collision limit. For the Landau equation for hard potentials in the style of Desvillettes-Villani (Comm. Partial Differential Equations, 2000), we provide the proof of the existence of axisymmetric measure-valued solution for any axisymmetric $\mathcal{P}_p(\mathbb{R}^3)$ initial profile for any $p\ge 2$. Moreover, we prove that if the initial data is not a single Dirac mass, then the solution instantaneously becomes analytic for any time $t>0$ in the hard potential case. In the soft potential and the Maxwellian molecule cases, we show that there are no solutions whose support is contained in a fixed line even for any given line-concentrated data.

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Jin Woo Jang, Junha Kim. 2025-01-24. On the axially symmetric solutions to the spatially homogeneous Landau equation. https://arxiv.org/abs/2501.07393

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