{ "id": "2501.07393", "version": "v2", "published": "2025-01-13T15:08:40.000Z", "updated": "2025-01-24T07:11:09.000Z", "title": "On the axially symmetric solutions to the spatially homogeneous Landau equation", "authors": [ "Jin Woo Jang", "Junha Kim" ], "comment": "22 pages. This version includes additional references on the grazing collision limit and the semi-classical limit", "categories": [ "math.AP" ], "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.", "revisions": [ { "version": "v2", "updated": "2025-01-24T07:11:09.000Z" } ], "analyses": { "subjects": [ "35Q20" ], "keywords": [ "spatially homogeneous landau equation", "axially symmetric solutions", "partial differential equations", "single dirac mass", "hard potential case" ], "note": { "typesetting": "TeX", "pages": 22, "language": "en", "license": "arXiv", "status": "editable" } } }