Livolsi, Edoardo: Perr review Elisa Maggio - LIGO - INFN A Review of Gravitational-Wave Echoes

from the Abyss: A Review of Gravitational-Wave Echoes from Black Hole Mimickers and Exotic Compact Objects by Elena Maggio. The central result of the present analysis is that the manuscript does not con- struct a closed generative physical framework, but rather develops an extensive perturbative phenomenology built entirely on externally imposed geometrical as- sumptions. Throughout the paper, spacetime geometry, causal structure, eective potentials, boundary conditions, compact-object reectivit