Speaker
Description
The LIGO-VIRGO-KAGRA observations are so far compatible with the Kerr black hole paradigm, though they cannot rule out entirely the existence of black hole mimickers. These are ultracompact objects that reproduce some observable properties of black holes, while possibly predicting characteristic signatures such as non-trivial tidal deformability and/or repeated gravitational wave echoes in the ringdown.
Interesting families of ultracompact objects called "topological solitons" consist in regular and horizonless solutions to five-dimensional Einstein-Maxwell theory, which resemble static black holes upon reduction to four dimensions. These mimickers can also serve as a classical toy model for the quantum black hole microstates constructed in the ``fuzzball” program in the context of string theory.
In this talk we will present our latest results concerning the linear response of topological solitons, with a focus on their characteristic spectrum, gravitational wave echoes and (linear) stability.