2010/01/11 by Justin Holmer, Holmer, Justin
Mathematics · Physics and Astronomy · #Analysis of PDEs (math.AP) #FOS: Mathematics #FOS: Physical sciences #Mathematical Physics (math-ph) #math-ph #math.AP #math.MP
paper · pdf · doi:10.48550/arxiv.1001.1583
arxiv created 2010/12/31 · arxiv updated 2011/01/04
We study the dynamics of solitons as solutions to the perturbed KdV (pKdV) equation ∂t u = -∂x (∂x2 u + 3u2-bu), where b(x,t) = b0(hx,ht), h≪ 1 is a slowly varying, but not small, potential. We option an explicit description of the trajectory of the soliton parameters of scale and position on the dynamically relevant time scale δh-1log h-1, together with an estimate on the error of size h1/2. In addition to the Lyapunov analysis commonly applied to these problems, we use a local virial estimate due to Martel-Merle (2005). The results are supported by numerics. The proof does not rely on the inverse scattering machinery and is expected to carry through for the L2 subcritical gKdV-p equation, 1<p<5. The case of p=3, the modified Korteweg-de Vries (mKdV) equation, is structurally simpler and more precise results can be obtained by the method of Holmer-Zworski (2007).