{ "id": "1804.10403", "version": "v1", "published": "2018-04-27T09:00:42.000Z", "updated": "2018-04-27T09:00:42.000Z", "title": "Well-posedness and stability results for some periodic Muskat problems", "authors": [ "Bogdan-Vasile Matioc" ], "comment": "52 pages, 1 figure", "categories": [ "math.AP" ], "abstract": "We study the two-dimensional Muskat problem in a horizontally periodic setting and for fluids with arbitrary densities and viscosities. We show that in the presence of surface tension effects the Muskat problem is a quasilinear parabolic problem which is well-posed in the Sobolev space $H^r(\\mathbb{S})$ for each $r\\in(2,3)$. When neglecting surface tension effects, the Muskat problem is a fully nonlinear evolution equation and of parabolic type in the regime where the Rayleigh-Taylor condition is satisfied. We then establish the well-posedness of the Muskat problem in the open subset of $H^2(\\mathbb{S})$ defined by the Rayleigh-Taylor condition. Besides, we identify all equilibrium solutions and study the stability properties of trivial and of small finger-shaped equilibria. Also other qualitative properties of solutions such as parabolic smoothing, blow-up behavior, and criteria for global existence are outlined.", "revisions": [ { "version": "v1", "updated": "2018-04-27T09:00:42.000Z" } ], "analyses": { "subjects": [ "35B35", "35B65", "35K55", "35Q35", "42B20" ], "keywords": [ "periodic muskat problems", "stability results", "well-posedness", "rayleigh-taylor condition", "quasilinear parabolic problem" ], "note": { "typesetting": "TeX", "pages": 52, "language": "en", "license": "arXiv", "status": "editable" } } }