The group's research on strong gravity involves finding analytical and numerical solutions of Einstein's theory of general relativity, and many of its extensions, either in vacuum or coupled to various types of matter. For our latest developments/activities in this area, please see the listing at the end of this article.
The prime examples of (relativistic) strong gravitational systems are Black Holes. They are truly unifying objects of all physics. The understanding of their formation and dynamics requires the laws of all four fundamental forces, and their physics is relevant not only for astrophysics and cosmology but for a variety of topics within high energy physics.
See here a movie made by the COST action `Black holes in a violent universe', in which our group participates, for a visual overview of different types of black holes.
Two asymptotically flat spinning black holes balanced by their self-interacting, synchronised scalar hair, C. Liang, C. Herdeiro, E. Radu; arXiv:2605.20374 [gr-qc].
Electromagnetic duality degeneracy in dynamical black hole mergers, J. Ferreira, G. Bozzola, C. A. R. Herdeiro, V. Paschalidis, M. Zilhão; arXiv:2605.20493 [gr-qc].
Vacuum, ma non troppo: hidden matter distribution in symmetry-transformed electrovacuum spacetimes, C. A. R. Herdeiro, J. P. A. Novo; arXiv:2605.18967 [gr-qc].
Multipolar Proca stars: electric, magnetic and hybrid solitons, C. Herdeiro, E. Radu, E. S. Costa Filho, N. Sanchis-Gual; arXiv:2605.13965 [gr-qc]
Spontaneous spherical symmetry breaking of black holes with resonant hair, J. Ferreira, C. A. R. Herdeiro, E. Radu, M. Zilhão; arXiv:2604.22437 [gr-qc].
We present and study new nontopological soliton solutions in the U(1) gauged nonlinear O(3) sigma-model with a symmetry breaking potential in 3+1 dimensional space-time. The configurations are endowed with an electric and magnetic field and also carry a nonvanishing angular momentum density.
Member of Gr@v H. Olivares participated at the Spanish and Portuguese Relativity Meeting 2026, held in Murcia, Spain, to deliver an invited talk on simulating and observing black hole mimickers.
We investigate the absorption of massless scalar waves by three distinct hairy black hole solutions obtained through the gravitational decoupling method, considering the weak, the strong or the dominant energy conditions.