{ "id": "2109.04233", "version": "v1", "published": "2021-09-09T12:52:06.000Z", "updated": "2021-09-09T12:52:06.000Z", "title": "A new varifold solution concept for mean curvature flow: Convergence of the Allen-Cahn equation and weak-strong uniqueness", "authors": [ "Sebastian Hensel", "Tim Laux" ], "comment": "37 pages", "categories": [ "math.AP", "math.DG" ], "abstract": "We propose a new weak solution concept for (two-phase) mean curvature flow which enjoys both (unconditional) existence and (weak-strong) uniqueness properties. These solutions are evolving varifolds, just as in Brakke's formulation, but are coupled to the phase volumes by a simple transport equation. First, we show that, in the exact same setup as in Ilmanen's proof [J. Differential Geom. 38, 417-461, (1993)], any limit point of solutions to the Allen-Cahn equation is a varifold solution in our sense. Second, we prove that any calibrated flow in the sense of Fischer et al. [arXiv:2003.05478] - and hence any classical solution to mean curvature flow - is unique in the class of our new varifold solutions. This is in sharp contrast to the case of Brakke flows, which a priori may disappear at any given time and are therefore fatally non-unique. Finally, we propose an extension of the solution concept to the multi-phase case which is at least guaranteed to satisfy a weak-strong uniqueness principle.", "revisions": [ { "version": "v1", "updated": "2021-09-09T12:52:06.000Z" } ], "analyses": { "subjects": [ "53E10", "49Q20", "35K57", "35Q49", "28A75" ], "keywords": [ "mean curvature flow", "varifold solution concept", "allen-cahn equation", "convergence", "weak solution concept" ], "note": { "typesetting": "TeX", "pages": 37, "language": "en", "license": "arXiv", "status": "editable" } } }