{ "id": "2105.12193", "version": "v1", "published": "2021-05-25T20:14:35.000Z", "updated": "2021-05-25T20:14:35.000Z", "title": "Bifurcation Theory for Fredholm Operators", "authors": [ "Julián López-Gómez", "Juan Carlos Sampedro" ], "categories": [ "math.AP" ], "abstract": "This paper consists of four parts. It begins by using the authors's generalized Schauder formula, \\cite{JJ}, and the algebraic multiplicity, $\\chi$, of Esquinas and L\\'{o}pez-G\\'{o}mez \\cite{ELG,Es,LG01} to package and sharpening all existing results in local and global bifurcation theory for Fredholm operators through the recent author's axiomatization of the Fitzpatrick--Pejsachowicz--Rabier degree, \\cite{JJ2}. This facilitates reformulating and refining all existing results in a compact and unifying way. Then, the local structure of the solution set of $\\mathfrak{F}(\\lambda,u)=0$ at a simple degenerate eigenvalue is ascertained by means of some concepts and devices of Algebraic Geometry and Galois Theory, which establishes a bisociation between Bifurcation Theory and Algebraic Geometry. Further, we combine the theorem of structure of analytic manifolds with a brilliant idea of Buffoni and Toland \\cite{BT} to show that the solution sets of the most paradigmatic one-dimensional boundary value problems with analytic nonlinearities actually consist of global analytic arcs of curve. Finally, the unilateral theorems of \\cite{LG01,LG02}, as well as the refinement of Xi and Wang \\cite{XW}, are substantially generalized. This paper also analyzes two important examples to illustrate and discuss the relevance of the abstract theory. The second one studies the regular positive solutions of a multidimensional quasilinear boundary value problem of mixed type related to the mean curvature operator.", "revisions": [ { "version": "v1", "updated": "2021-05-25T20:14:35.000Z" } ], "analyses": { "subjects": [ "34B15", "35J93", "47H11", "58C40" ], "keywords": [ "bifurcation theory", "fredholm operators", "paradigmatic one-dimensional boundary value problems", "multidimensional quasilinear boundary value problem", "solution set" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }