Effective Field Theory for the perturbations of a slowly rotating black hole

We develop the effective theory for perturbations around black holes with scalar hair, in two directions. First, we show that the scalar-Gauss-Bonnet theory, often used as an example exhibiting scalar black hole hair, can be deformed by galileon operators leading to order unity changes to its predictions. The effective theory for perturbations thus provides an efficient framework for describing and constraining broad classes of scalar-tensor theories, of which the addition of galileon operators is an example. Second, we extend the effective theory to perturbations around an axisymmetric, slowly rotating black hole, at linear order in the black hole spin. We also discuss the inclusion of parity-breaking operators in the effective theory.

Automated summary

This study develops an effective theory in two directions for perturbations around black holes with scalar hair, including transformations of the scalar-Gauss-Bonnet theory and perturbations around an axisymmetric, slowly rotating black hole. By utilizing methods like galileon operators, the effective theory for perturbations efficiently describes and constrains a broad range of scalar-tensor theories.