Talks

Wave equation for integer spin fields
A second look at no-hair properties
Tidal properties of black holes
Dynamics: the QNMs of black holes
Resonant excitation of modes?
Wave phenomena for massive fields
Summary

- BH mimickers: classifications and open problems.
- Buchdhal's theorem and how to evade it
- Maximum compactness in GR and beyond
- Models of BH mimickers*:
    - Boson stars
    - Anisotropic/elastic stars
    - Fuzzballs/BH microstates

- BHs vs mimickers: no-hair theorems, breaking of axial/equatorial symmetry
- GW modelling*

* only basic aspects, room for tutorials. The goal would be to see how the quadrupole moment enters the waveform of a binary

Gravitational wave signals from merging compact binary systems provide unique avenues for testing the general theory of relativity (GR) predictions in the strong-field, dynamic, and relativistic regimes. As the gravitational wave (GW) transient catalogue grows in number and source diversity, designing and implementing tests for these predictions in model-agnostic ways and for specific alternative theory predictions is mandatory. In this presentation, I will introduce the routinely employed model-agnostic tests of the nature of compact objects using the observed binary population and implications of such constraints to alternative models. Then, I will describe theory-specific tests of the nature of compact objects, focusing on spinning black holes in modified GR theories and discuss the possible constraints on such models from current and future GW observations.

Stationarity & vacuum versus real universe

Matter around BHs: circular motion, stability, unstable light rings and their decay time. Cross-section for absorption

Spinning black holes: the static limit and the ergoregion, energy extraction

Testing the Cosmic Censor

Forming black holes: the Hoop conjecture