Scattering from charged black holes and supergravity

The scattering cross sections of the unpolarized electromagnetic and gravitational waves are shown to be equal for the extreme Reissner-Nordström black hole using $N=2$ supergravity. The conversion cross sections between the unpolarized electromagnetic and gravitational waves are also shown to coincide. The gravitational and electromagnetic scattering cross sections are computed numerically for Reissner-Nordström black holes for several charge-to-mass ratios and the coincidence between the two scattering cross sections for the extremal case is confirmed.

Figure 1

Scattering cross section for scalar ($s=0$), electromagnetic ($s=1$), and gravitational ($s=2$) radiation for Schwarzschild black holes (top), Reissner-Nordström with $q\equiv |Q|/M=0.8$ (middle), and extreme Reissner-Nordström black holes (bottom). Here, $M\omega =3.0$.