Watch the presentation movie of the COST Action CA16104 Gravitational waves, black holes and fundamental physics (GWverse), in which Gr@v is involved as part of the core group.
The movie was created at the University of Aveiro (Portugal), written and directed by Carlos Herdeiro, with Design and Graphics by Joana Reis and Ana Sousa and Edited by Pedro Henriques.
The article "Stimulated axion decay in superradiant clouds around astrophysical black holes" (arXiv:1709.06581), co-authored by Gr@v member João Rosa and Tom Kephart (Vanderbilt University, USA), has been accepted for publication in Physical Review Letters and will be highlighted as one of the PRL Editors' Suggestions (a distinction attributed to about one in six Letters).
Black hole (BH) shadows in dynamical binary BHs have been produced via ray-tracing techniques on top of computationally expensive fully non-linear numerical relativity simulations.
On arXiv:1805.03798 [gr-qc], it is illustrated (as a proof of concept) that the main features of these shadows can be captured by a simple quasi-static evolution of the photon orbits on top of a static double-Schwarzschild family of solutions, which is exact.
A team of Gr@v members (P. Cunha, J. Delgado, C. Herdeiro and J. Oliveira) is visiting the Universidad Nacional Autónoma de México, at its Cuernava Campus, in April-May 2018 hosted by Professor Juan Carlos Degollado. The visit occurs within a Marie Curie RISE action, of which both UNAM and Aveiro Universities are partners.
On May 29th, 1919 a joint Royal Astronomical Society and Royal Society expedition led by Arthur Eddington to Principe observed a total solar eclipse, confirming the deflexion of light predicted by the General Theory of Relativity. Eddington at Sundy: 100 years later (E@S) results from a joint initiative of several institutions, including our group, to celebrate the centenary of these observations.
Brown dwarfs are objects that bridge the realms of stars and planets. With masses below ~0.08 MSun, they cannot sustain hydrogen fusion, never reach the main sequence, and remain cooling forever. Star forming regions and young clusters harbour large populations of these substellar objects, including some with masses comparable to those of giant extrasolar planets.
The invited review article "Shadows and strong gravitational lensing: a brief review", by Gr@v members P. Cunha and C. Herdeiro was selected as Editor's choice in General Relativity and Gravitation.
The black hole theorist and cosmologist Stephen Hawking passed away at the age of 76. Stephen Hawking distinguished himself not only as a brilliant scientist, with remarkable contributions such as the discovery of black hole evaporation, but also as an active science communicator with best selling books, most notably A brief history of time.
Recent advances in radio telescopes in sensitivity, response time, and wavelength coverage have opened a wealth of new research opportunities. This is particularly the case for transients, where high sensitivity and rapid response is crucial. I will describe how radio observations of two classes of objects are helping to further our understanding of jet physics.
