{ "id": "1407.7445", "version": "v1", "published": "2014-07-28T15:28:24.000Z", "updated": "2014-07-28T15:28:24.000Z", "title": "Global smooth solutions of 3-D quasilinear wave equations with small initial data", "authors": [ "Ding Bingbing", "Liu Yingbo", "Yin Huicheng" ], "comment": "41 pages", "categories": [ "math.AP" ], "abstract": "In this paper, we are concerned with the 3-D quasilinear wave equation $ \\ds\\sum_{i,j=0}^3g^{ij}(u, \\p u)\\p_{ij}^2u$ $=0$ with $(u(0,x), \\p_tu(0,x))=(\\ve u_0(x), \\ve u_1(x))$, where $x_0=t$, $x=(x_1, x_2, x_3)$, $\\p=(\\p_0, \\p_1, ..., \\p_3)$, $u_0(x), u_1(x)\\in C_0^\\infty(\\Bbb R^3)$, $\\ve>0$ is small enough, and $g^{ij}(u, \\p u)=g^{ji}(u, \\p u)$ are smooth in their arguments. Without loss of generality, one can write $g^{ij}(u, \\p u)=c^{ij}+d^{ij}u+\\ds\\sum_{k=0}^3e^{ij}_k\\p_ku+O(|u|^2+|\\p u|^2)$, where $c^{ij}, d^{ij}$ and $e^{ij}_k$ are some constants, and $\\ds\\sum_{i,j=0}^3c^{ij}\\p_{ij}^2=-\\square\\equiv -\\p_t^2+\\Delta$. When $\\ds\\sum_{i,j,k=0}^3e^{ij}_k\\o_k\\o_i\\o_j\\not\\equiv 0$ for $\\o_0=-1$ and $\\o=(\\o_1, \\o_2, \\o_3)\\in\\Bbb S^2$, the authors in [7-8] have shown the blowup of the smooth solution $u$ in finite time as long as $(u_0(x), u_1(x))\\not\\equiv 0$. In the present paper, when $\\ds\\sum_{i,j,k=0}^3e^{ij}_k\\o_k\\o_i\\o_j\\equiv 0$, we will prove the global existence of the smooth solution $u$. Therefore, the complete results on the blowup or global existence of the small data solutions have been established for the general 3-D quasilinear wave equations $\\ds\\sum_{i,j=0}^3g^{ij}(u, \\p u)\\p_{ij}^2u=0$.", "revisions": [ { "version": "v1", "updated": "2014-07-28T15:28:24.000Z" } ], "analyses": { "subjects": [ "35L05", "35L72" ], "keywords": [ "quasilinear wave equation", "small initial data", "global smooth solutions", "global existence", "small data solutions" ], "note": { "typesetting": "TeX", "pages": 41, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1407.7445B" } } }