{ "id": "2308.01580", "version": "v1", "published": "2023-08-03T07:35:58.000Z", "updated": "2023-08-03T07:35:58.000Z", "title": "Finite element approximation of the Hardy constant", "authors": [ "Francesco Della Pietra", "Giovanni Fantuzzi", "Liviu I. Ignat", "Alba Lia Masiello", "Gloria Paoli", "Enrique Zuazua" ], "comment": "18 pages, 6 figures", "categories": [ "math.NA", "cs.NA", "math.AP" ], "abstract": "We consider finite element approximations to the optimal constant for the Hardy inequality with exponent $p=2$ in bounded domains of dimension $n=1$ or $n\\geq 3$. For finite element spaces of piecewise linear and continuous functions on a mesh of size $h$, we prove that the approximate Hardy constant, $S_h^n$, converges to the optimal Hardy constant $S^n$ no slower than $O(1/\\vert \\log h \\vert)$. We also show that the convergence is no faster than $O(1/\\vert \\log h \\vert^2)$ if $n=1$ or if $n\\geq 3$, the domain is the unit ball, and the finite element discretization exploits the rotational symmetry of the problem. Our estimates are compared to exact values for $S_h^n$ obtained computationally.", "revisions": [ { "version": "v1", "updated": "2023-08-03T07:35:58.000Z" } ], "analyses": { "subjects": [ "65N30", "46E35" ], "keywords": [ "finite element approximation", "finite element discretization exploits", "approximate hardy constant", "optimal hardy constant", "finite element spaces" ], "note": { "typesetting": "TeX", "pages": 18, "language": "en", "license": "arXiv", "status": "editable" } } }