{ "id": "2209.01063", "version": "v1", "published": "2022-09-02T13:54:49.000Z", "updated": "2022-09-02T13:54:49.000Z", "title": "Generic regularity of free boundaries for the thin obstacle problem", "authors": [ "Xavier Fernández-Real", "Damià Torres-Latorre" ], "categories": [ "math.AP" ], "abstract": "The free boundary for the Signorini problem in $\\mathbb{R}^{n+1}$ is smooth outside of a degenerate set, which can have the same dimension ($n-1$) as the free boundary itself. In [FR21] it was shown that generically, the set where the free boundary is not smooth is at most $(n-2)$-dimensional. Our main result establishes that, in fact, the degenerate set has zero $\\mathcal{H}^{n-3-\\alpha_0}$ measure for a generic solution. As a by-product, we obtain that, for $n+1 \\leq 4$, the whole free boundary is generically smooth. This solves the analogue of a conjecture of Schaeffer in $\\mathbb{R}^3$ and $\\mathbb{R}^4$ for the thin obstacle problem.", "revisions": [ { "version": "v1", "updated": "2022-09-02T13:54:49.000Z" } ], "analyses": { "subjects": [ "35R35", "35B65" ], "keywords": [ "free boundary", "thin obstacle problem", "generic regularity", "degenerate set", "main result establishes" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }