Scattering of uncharged particles in the field of two extremely charged black holes

Abstract

We investigate the motion of uncharged particles scattered by a binary system consisting of extremely charged black holes in equilibrium as described by the Majumdar-Papapetrou solution. We focus on unbound orbits confined to the plane containing both black holes. We consider the two complementary situations of particles approaching the system along a direction parallel to the axis where the black holes are displaced and orthogonal to it. We numerically compute the scattering angle as a function of the particle's conserved energy parameter, which provides a gauge-invariant information of the scattering process. We also study the precession of a test gyroscope along such orbits and evaluate the accumulated precession angle after a full scattering, which is another gauge-invariant quantity.

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Tidal Forces in Majumdar-Papapetrou Spacetimes

“…If we do that, then the tidal tensor becomes diagonal at that specific angle. For instance, if we set ϕ 0 = 0 in (13) and choose Ψ 0 = 0 in (22), then the tidal forces in the radial and angular directions decouple at time τ = 0. In fact, whenever Ψ is an integer multiple of 2π, the tidal forces decouple according to:…”

“…One of such solutions is the Majumdar-Papapetrou (MP) metric [5,6] of extremely charged black holes in static equilibrium. The MP spacetime has been successfully used in the past as a toy model to investigate how the presence of a second black hole influences quasinormal ringing, shadows, Penrose energy extraction, and other typical black hole effects [7][8][9][10][11][12][13][14].…”

Multicenter solutions in Eddington-inspired Born–Infeld gravity

“…A particularly interesting property of this solution is its lack of symmetry in the a e-mail: gonzalo.olmo@uv.es b e-mail: orazi.emanuele@gmail.com (corresponding author) c e-mail: drubiera@ucm.es distribution of black holes. Many other solutions of this family and generalizations have been subsequently found and characterized in the literature regarding their astrophysical features [16][17][18][19][20][21][22].…”