Wave dynamics of phantom scalar perturbation in the background of   Schwarzschild black hole
  Using Leaver's continue fraction and time domain method, we investigate the wave dynamics of phantom scalar perturbation in the background of Schwarzschild black hole. We find that the presence of the negative kinetic energy terms modifies the standard results in quasinormal spectrums and late-time behaviors of the scalar perturbations. The phantom scalar perturbation in the late-time evolution will grow with an exponential rate. 
Songbai Chen, Jiliang Jing, Qiyuan Pan