Vyacheslav Dokuchaev
2013 Particle Physics at the Tercentenary of Mikhail Lomonosov  
We consider test planet and photon orbits of the third kind inside a black hole, which are stable, periodic and neither come out of the black hole nor terminate at the singularity. Interiors of supermassive black holes may be inhabited by advanced civilizations living on planets with the third-kind orbits. In principle, one can get information from the interiors of black holes by observing their white hole counterparts. Orbits of the third kind were described in [1, 2, 3, 4, 5] under the
more » ... 5] under the assumption of the Kerr-Newman metric validity inside a black hole event horizon. The motion of a test particle (e. g., a planet) with mass µ and electric charge ǫ in the background gravitational field of a Kerr-Newman black hole (BH) with mass M , angular momentum J = M a and electric charge e is completely defined by three integrals of motion: the total particle energy E, the azimuthal component of the angular momentum L and the Carter constant Q, related to the total angular momentum of the particle. An orbital trajectory of a test planet is governed in the Boyer-Lindquist coordinates (t, r, θ, ϕ) by the equations of motion [6
doi:10.1142/9789814436830_0057 fatcat:3vkdmmobjvhivm5pqwkvleao5i