{ "id": "1808.01685", "version": "v1", "published": "2018-08-05T21:07:06.000Z", "updated": "2018-08-05T21:07:06.000Z", "title": "Sharp estimate of global Coulomb gauge", "authors": [ "Yu Wang" ], "categories": [ "math.DG", "math.AP" ], "abstract": "Let $A$ be a $W^{1,2}$-connection on a principle $\\text{SU}(2)$-bundle $P$ over a compact $4$-manifold $M$ whose curvature $F_A$ satisfies $\\|F_A\\|_{L^2(M)}\\le \\Lambda$. Our main result is the existence of a global section $\\sigma: M\\to P$ with finite singularities on $M$ such that the connection form $\\sigma^*A$ satisfies the Coulomb equation $d^*(\\sigma^*A)=0$ and admits a sharp estimate $\\|\\sigma^*A\\|_{\\mathcal{L}^{4,\\infty}(M)}\\le C(M,\\Lambda)$. Here $\\mathcal{L}^{4,\\infty}$ is a new function space we introduce in this paper that satisfies $L^4(M)\\subsetneq \\mathcal{L}^{4,\\infty}(M)\\subsetneq L^{4-\\epsilon}(M)$ for all $\\epsilon>0$.", "revisions": [ { "version": "v1", "updated": "2018-08-05T21:07:06.000Z" } ], "analyses": { "keywords": [ "global coulomb gauge", "sharp estimate", "function space", "coulomb equation", "connection form" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }