I will sketch motivations, ambitions and challenges of quantum gravity, how we have got to where we are, and discuss promising current and future direction, focusing on nonperturbative quantum field-theoretic approaches. No expert knowledge on quantum gravity will be required.
The detection of gravitational waves has been one of the most exciting scientific developments of the XXIst century. These detections are theory-driven, they rely on the existence of waveform libraries, which have been constructed for binary black holes and neutron stars. Gr@v members have collaborated on the construction of the first waveform catalogue for exotic compact objects, an effort led by former Gr@v member Nicolas Sanchis Gual (now at the U. Valencia).
The black hole merger in scalar-Gauss-Bonnet gravity can lead to dynamical descalarization this is a spontaneous release of the scalar
hair of the newly formed black hole. Depending on the exact form of the Gauss-Bonnet coupling function, the stable scalarized solutions
Non-linear extensions of Proca theory are pathological at large field amplitudes. I will explain why. I will also discuss a separate criterion for breakdown proposed in the literature, and why it does not correspond to a real physical problem
The theory of General Relativity has successfully passed a large number of observational tests. The theory has been extensively tested in the weak-field regime with experiments in the Solar System and observations of binary pulsars.
In the paper "The fate of the light-ring instability" Gr@v members P. Cunha, C. Herdeiro and E. Radu, together with former member, currently at the U. Valencia, N. Sanchis-Gual, have unveiled the mystery of the fate of a large class of horizonless ultracompact objects, that could be potential black hole foils.
A long standing intriguing possibility is if the astrophysical black hole candidates could be some other kind of mysterious objects but without event horizons, the defining property of black holes.
The project "Gravitational waves, black holes, and fundamental physics" led by M. Zilhão (co-PI C.Herdeiro), fully based at Aveiro U., was one of the six Scientific Research and Technological Development Projects selected for funding in the 2022 FCT Call for R&D projects in the Physics panel. All results can be seen here.
Our group coordinated the "Numerical Relativity and High Energy Physics" IRSES network (2012-2015). Here is a list of the global network meetings organized:
