5 papers
Beyond quasinormal modes: a complete mode decomposition of black hole perturbations
Paolo Arnaudo, Javier Carballo, Benjamin Withers
We show that retarded Green's functions of black hole spacetimes can be expressed as a convergent mode sum everywhere in spacetime. At late times a quasinormal mode sum converges,…
QNM orthogonality relations for AdS black holes
Paolo Arnaudo, Javier Carballo, Benjamin Withers
We present orthogonality relations for quasinormal modes of a wide class of asymptotically AdS black holes. The definition is obtained from a standard product, modified by a CPT op…
Non-modal effects in black hole perturbation theory: Transient Superradiance
Javier Carballo, Christiana Pantelidou, Benjamin Withers
We study the non-modal stability of black hole spacetimes under linear perturbations. We show that large-amplitude growth can occur at finite time, despite asymptotic decay of line…
Transients in black hole perturbation theory
Jérémy Besson, Javier Carballo, Christiana Pantelidou +1
Black hole quasinormal modes arise as eigenmodes of a non-normal Hamiltonian and consequently they do not obey orthogonality relations with respect to commonly used inner products,…
Transient dynamics of quasinormal mode sums
Javier Carballo, Benjamin Withers
Quasinormal modes of spacetimes with event horizons are typically governed by a non-normal operator. This gives rise to spectral instabilities, a topic of recent interest in the bl…