Global dynamics below excited solitons for the nonlinear Schrödinger equation with a potential (Q1687570)

The purpose of this paper is to study several variants of the NLS equation. This study is concentrated on the two ground states, i.e. the least energy solitons. The main result states that the solution of a NLS equation with a potential with a single negative eigenvalue either blows up in finite time or scatters as \(t\to\pm\infty\) to the first ground state. Then modulation and linearized equations around the ground state are analyzed. The proofs use implicit function theorem, Ascoli-Arzela theorem, Lagrange multipliers, Duhamel formula, Strichart estimate, Gagliardi-Nirenberg, Hölder, radial Sobolev, Sobolev, Cauchy-Schwarz and Hölder inequalities. A table of notation is given in the end.