{ "id": "2103.13004", "version": "v1", "published": "2021-03-24T06:17:57.000Z", "updated": "2021-03-24T06:17:57.000Z", "title": "On the $ C^{8/3} $-Regularisation of Simultaneous Binary Collisions in the Planar 4-Body Problem", "authors": [ "Nathan Duignan", "Holger R. Dullin" ], "comment": "34 pages, 4 figures", "categories": [ "math.DS" ], "abstract": "The dynamics of the 4-body problem allows for two binary collisions to occur simultaneously. It is known that in the collinear 4-body problem this simultaneous binary collision (SBC) can be block-regularised, but that the resulting block map is only $C^{8/3}$ differentiable. In this paper, it is proved that the $C^{8/3}$ differentiability persists for the SBC in the planar 4-body problem. The proof uses several geometric tools, namely, blow-up, normal forms, dynamics near normally hyperbolic manifolds of equilibrium points, and Dulac maps.", "revisions": [ { "version": "v1", "updated": "2021-03-24T06:17:57.000Z" } ], "analyses": { "subjects": [ "70F16", "70F10" ], "keywords": [ "simultaneous binary collision", "regularisation", "dulac maps", "equilibrium points", "normally hyperbolic manifolds" ], "note": { "typesetting": "TeX", "pages": 34, "language": "en", "license": "arXiv", "status": "editable" } } }