Lindblad resonance torques in relativistic discs: I. Basic equations

Understand

Lindblad resonances have been suggested as an important mechanism for angular momentum transport and heating in discs in binary black hole systems.

• We present the basic equations for the torque and heating rate for relativistic thin discs subjected to a perturbation.
• The Lindblad resonance torque is written explicitly in terms of metric perturbations for an equatorial disc in a general axisymmetric, time-stationary spacetime with a plane of symmetry.
• We show that the resulting torque formula is gauge-invariant.