In the article "Stationary black holes and light rings" by P. Cunha and C. Herdeiro, published in Physical Review Letters, as Editor's Suggestion, a theorem is proven establishing that, under very generic conditions, any black hole must have a light ring.
Research cannot stop, even in this exceptional time! Gr@v member keep meeting virtually to push the group activities.
Recently, a novel modified theory of gravity that claims to bypass Lovelock's theorem whilst preserving the number of gravitational degrees of freedom has attracted a great deal of attention.
Discussion of the paper "Spherical electro-vacuum black holes with resonant, scalar Q-hair",
ArXiv:2004.00336
A recent breakthrough in the separability of the Proca equation in Kerr spacetime opened up new opportunities for a thorough study of fast-growi
Advanced interferometric techniques as those employed in the Event Horizon Telescope (EHT) and GRAVITY recently allowed to study the environment of the two nearest supermassive black hole candidates at horizon-scale resoluton.
Fabrizio di Giovanni gave us a nice update on the dynamical properties of bosonic stars, from numerical relativity simulations.
Fabrizio di Giovanni (Valencia U., Spain), Kunihito Uzawa (Kwansei Gakuin U., Japan) and Nico Sanchis-Gual (IST-Lisbon) visited our group in the second week of March. Many scientific discussions and hard work were rewarded with a very nice dinner in Aveiro!
Kunihito Uzawa (Kwansei Gakuin U., Japan) gave us a nice update on the swampland conjecture and its implications in cosmology.
Gr@v member C. Herdeiro gave an invited colloquium at the Centre for Mathematical Sciences, U. Cambridge, of the GR and HEP groups on March 4th and an invited seminar at STAG, School of Mathematical Sciences, U. Southampton in March 5th.