Stability and instability of radial standing waves to NLKG equation with an inverse-square potential

Abstract

In this paper, we consider radial standing waves to a nonlinear Klein-Gordon equation with a repulsive inverse-square potential. It is known that there exist “radial” ground states to the stationary problem of the nonlinear Klein-Gordon equation. Here, “radial” ground states are non-trivial solutions having least energy among all non-trivial radial solutions to the stationary equation. We deal with the stability and instability of “radial” ground state standing waves.