{ "id": "1103.3838", "version": "v1", "published": "2011-03-20T09:06:31.000Z", "updated": "2011-03-20T09:06:31.000Z", "title": "A new conformal invariant on 3-dimensional manifolds", "authors": [ "Yuxin Ge", "Guofang Wang" ], "comment": "23 pages", "categories": [ "math.DG", "math.AP" ], "abstract": "By improving the analysis developed in the study of $\\s_k$-Yamabe problem, we prove in this paper that the De Lellis-Topping inequality is true on 3-dimensional Riemannian manifolds of nonnegative scalar curvature. More precisely, if $(M^3, g)$ is a 3-dimensional closed Riemannian manifold with non-negative scalar curvature, then \\[\\int_M |Ric-\\frac{\\bar R} 3 g|^2 dv (g)\\le 9\\int_M |Ric-\\frac{R} 3 g|^2dv(g), \\] where $\\bar R=vol (g)^{-1} \\int_M R dv(g)$ is the average of the scalar curvature $R$ of $g$. Equality holds if and only if $(M^3,g)$ is a space form. We in fact study the following new conformal invariant \\[\\ds \\widetilde Y([g_0]):=\\sup_{g\\in {\\cal C}_1([g_0])}\\frac {\\ds vol(g)\\int_M \\s_2(g) dv(g)} {\\ds (\\int_M \\s_1(g) dv(g))^2}, \\] where ${\\cal C}_1([g_0]):=\\{g=e^{-2u}g_0\\,|\\, R>0\\}$ and prove that $\\widetilde Y([g_0])\\le 1/3$, which implies the above inequality.", "revisions": [ { "version": "v1", "updated": "2011-03-20T09:06:31.000Z" } ], "analyses": { "subjects": [ "53C21", "53C20", "58E11" ], "keywords": [ "conformal invariant", "fact study", "nonnegative scalar curvature", "yamabe problem", "closed riemannian manifold" ], "note": { "typesetting": "TeX", "pages": 23, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2011arXiv1103.3838G" } } }