Standing waves for quasilinear Schröinger equations with indefinite potentials
arXiv:1801.01976
Abstract
We consider quasilinear Schrödinger equations in of the form% \[ -Δu+V(x)u-uΔ(u^{2})=g(u)\text{,}% \] where is -superlinear. Unlike all known results in the literature, the Schrödinger operator is allowed to be indefinite, hence the variational functional does not satisfy the mountain pass geometry. By a local linking argument and Morse theory, we obtain a nontrivial solution for the problem. In case that is odd, we get an unbounded sequence of solutions.