2008/11/07 by Qidi Zhang, Zhang, Qidi
Mathematics · #Analysis of PDEs (math.AP) #FOS: Mathematics #math.AP
paper · pdf · doi:10.48550/arxiv.0811.1152
arxiv created 2008/11/07 · arxiv updated 2009/12/01
We prove that small smooth solutions of semi-linear Klein-Gordon equations with quadratic potential exist over a longer interval than the one given by local existence theory, for almost every value of mass. We use normal form for the Sobolev energy. The difficulty in comparison with some similar results on the sphere comes from the fact that two successive eigenvalues λ, λ' of √(-Δ+|x|2) may be separated by a distance as small as (1)/(√λ).