{ "id": "2401.05550", "version": "v1", "published": "2024-01-10T21:30:51.000Z", "updated": "2024-01-10T21:30:51.000Z", "title": "Counterexamples to maximal regularity for operators in divergence form", "authors": [ "Sebastian Bechtel", "Connor Mooney", "Mark Veraar" ], "categories": [ "math.AP", "math.CA" ], "abstract": "In this paper, we present counterexamples to maximal $L^p$-regularity for a parabolic PDE. The example is a second-order operator in divergence form with space and time-dependent coefficients. It is well-known from Lions' theory that such operators admit maximal $L^2$-regularity on $H^{-1}$ under a coercivity condition on the coefficients, and without any regularity conditions in time and space. We show that in general one cannot expect maximal $L^p$-regularity on $H^{-1}(\\mathbb{R}^d)$ or $L^2$-regularity on $L^2(\\mathbb{R}^d)$.", "revisions": [ { "version": "v1", "updated": "2024-01-10T21:30:51.000Z" } ], "analyses": { "subjects": [ "35K90", "35B65" ], "keywords": [ "divergence form", "maximal regularity", "counterexamples", "operators admit maximal", "parabolic pde" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }