{ "id": "1902.01680", "version": "v1", "published": "2019-02-05T14:01:26.000Z", "updated": "2019-02-05T14:01:26.000Z", "title": "Polynomial bounds on the Sobolev norms of the solutions of the nonlinear wave equation with time dependent potential", "authors": [ "Vesselin Petkov", "Nikolay Tzvetkov" ], "categories": [ "math.AP", "math-ph", "math.MP" ], "abstract": "We consider the Cauchy problem for the nonlinear wave equation $u_{tt} - \\Delta_x u +q(t, x) u + u^3 = 0$ with smooth and periodic in time potential $q(t, x) \\geq 0$ having compact support with respect to $x$. The linear equation without the nonlinear term $u^3$ may have solutions with exponentially increasing as $ t \\to \\infty$ norm $H^1({\\mathbb R}^3_x)$. In [2] it was established that adding the nonlinear term $u^3$ the $H^1({\\mathbb R}^3_x)$ of the solution is polynomially bounded for every choice of $q$. In this paper we show that $H^k({\\mathbb R}^3_x)$ norm of this global solution is also polynomially bounded. To prove this we apply a different argument based on the analysis of a sequence $\\{Y_k(n\\tau_k)\\}_{n = 0}^{\\infty}$ with suitably defined energy norm $Y_k(t)$ and $0 < \\tau_k <1.$", "revisions": [ { "version": "v1", "updated": "2019-02-05T14:01:26.000Z" } ], "analyses": { "subjects": [ "35L71", "35L15" ], "keywords": [ "nonlinear wave equation", "time dependent potential", "polynomial bounds", "sobolev norms", "nonlinear term" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }