{ "id": "1707.09943", "version": "v1", "published": "2017-07-31T16:26:58.000Z", "updated": "2017-07-31T16:26:58.000Z", "title": "A \"converse\" stability condition is necessary for a compact higher order scheme on non-uniform meshes", "authors": [ "Alexander Zlotnik", "Raimondas Čiegis" ], "comment": "6 pages, 2 figures, 1 table", "categories": [ "math.NA" ], "abstract": "The stability bounds and error estimates for a compact higher order Numerov-Crank-Nicolson scheme on non-uniform space meshes for the 1D time-dependent Schr\\\"odinger equation have been recently derived. This analysis has been done in $L^2$ and $H^1$ mesh norms and used the non-standard \"converse\" condition $h_\\omega\\leq c_0\\tau$, where $h_\\omega$ is the mean space step, $\\tau$ is the time step and $c_0>0$. Now we prove that such condition is necessary for some families of non-uniform meshes and any space norm. Also numerical results show unacceptably wrong behavior of numerical solutions (their dramatic mass non-conservation) when this condition is violated.", "revisions": [ { "version": "v1", "updated": "2017-07-31T16:26:58.000Z" } ], "analyses": { "subjects": [ "65M06", "65M12" ], "keywords": [ "compact higher order scheme", "non-uniform meshes", "stability condition", "compact higher order numerov-crank-nicolson scheme" ], "note": { "typesetting": "TeX", "pages": 6, "language": "en", "license": "arXiv", "status": "editable" } } }