On the Exact Solutions of the Regge-Wheeler Equation in the   Schwarzschild Black Hole Interior
  We solve exactly the Regge-Wheeler equation for axial perturbations of the Schwarzschild metric in the black hole interior in terms of Heun functions and give a description of the spectrum and the eigenfunctions of the interior problem. The phenomenon of attraction and repulsion of the discrete eigenvalues of gravitational waves is discovered. 
Plamen P. Fiziev