{ "id": "2310.14813", "version": "v1", "published": "2023-10-23T11:26:57.000Z", "updated": "2023-10-23T11:26:57.000Z", "title": "Catastrophe conditions for vector fields in $\\mathbb R^n$", "authors": [ "Mike R. Jeffrey" ], "journal": "J. Phys. A: Math. Theor. 55 464006 (2022)", "doi": "10.1088/1751-8121/aca36c", "categories": [ "math-ph", "math.DS", "math.MP" ], "abstract": "Practical conditions are given here for finding and classifying high codimension intersection points of $n$ hypersurfaces in $n$ dimensions. By interpreting those hypersurfaces as the nullclines of a vector field in $\\mathbb R^n$, we broaden the concept of Thom's catastrophes to find bifurcation points of (non-gradient) vector fields of any dimension. We introduce a family of determinants ${B}_j$, such that a codimension $r$ bifurcation point is found by solving the system ${B}_1=...={B}_r=0$, subject to certain non-degeneracy conditions. The determinants ${B}_j$ generalize the derivatives $\\frac{\\partial^j\\;}{\\partial x^j}F(x)$ that vanish at a catastrophe of a scalar function $F(x)$. We do not extend catastrophe theory or singularity theory themselves, but provide a means to apply them more readily to the multi-dimensional dynamical models that appear, for example, in the study of various engineered or living systems. For illustration we apply our conditions to locate butterfly and star catastrophes in a second order PDE.", "revisions": [ { "version": "v1", "updated": "2023-10-23T11:26:57.000Z" } ], "analyses": { "subjects": [ "34Cxx", "37Nxx", "35Axx", "53Zxx" ], "keywords": [ "vector field", "catastrophe conditions", "classifying high codimension intersection points", "bifurcation point", "extend catastrophe theory" ], "tags": [ "journal article" ], "publication": { "publisher": "IOP" }, "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }