{ "id": "1801.01327", "version": "v1", "published": "2018-01-04T12:37:47.000Z", "updated": "2018-01-04T12:37:47.000Z", "title": "Frobenius Theorem in Banach Space", "authors": [ "Jipu Ma" ], "comment": "arXiv admin note: text overlap with arXiv:1407.5198", "categories": [ "math.FA" ], "abstract": "Let $\\Lambda$ be an open set in Banach space $E$, $M(x)$ for $x\\in \\Lambda$ a subspace in $E$, and $\\mathcal F=\\{M(x)\\}_{x\\in\\Lambda}$. In this paper, we introduce the concept of the co-final set $J(x_0,E_*)$ for $\\mathcal F$ at $x_0\\in \\Lambda$, then prove Frobenius theorem in Banach space where especially, $\\mathrm{dim}\\, M(x)$ maybe $\\infty$. Using the Frobenius theorem, we prove a theorem in advanced calulus that presents several $c^1$ integrable family $\\mathcal F$ at a point with $\\mathrm{dim}\\, M(x) =\\infty$ and trivial co-final set. Let $\\Lambda=B(E,F)\\setminus\\{0\\},\\ M(X)=\\{T\\in B(E,F) : TN(X)\\subset R(X)\\}$, and $\\mathcal F=\\{M(X)\\}_{X\\in\\Lambda}$. The following theorem is proved using Frobenius theorem: if $A\\in\\Lambda$ is double splitting, then $\\mathcal F$ at $A$ is smooth integrable where $J(A,E_*)$ is non-trivial in general. Specially we have the global result as follows, let $\\Phi$ be any one of $F_k(k<\\infty)$ and $\\Phi_{m,n}(\\min\\{m,n\\}<\\infty)$, then $\\Phi$ is smooth submanifold in $B(E,F)$ and tangent to $M(X)$ at any $X$ in $\\Phi$.", "revisions": [ { "version": "v1", "updated": "2018-01-04T12:37:47.000Z" } ], "analyses": { "subjects": [ "46T99", "37C05", "53C40", "58A03" ], "keywords": [ "frobenius theorem", "banach space", "trivial co-final set", "open set", "smooth submanifold" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }