Horizon-scale images of black holes (BHs) and their shadows have opened an
unprecedented window onto tests of gravity and fundamental physics in the strong-field …

Ultralight bosons can affect the dynamics of spinning black holes (BHs) via superradiant
instability, which can lead to a time evolution of the supermassive BH shadow. We study …

Abstract The Event Horizon Telescope (EHT) Collaboration recently published the first
images of the supermassive black holes in the cores of the Messier 87 and Milky Way …

Black hole (BH) shadows can be used to probe new physics in the form of ultralight particles
via the phenomenon of superradiant instability. By directly affecting the BH mass and spin …

In general relativity, isolated black holes are invisible due to the infinitely large redshift of
photons propagating from the event horizon to a remote observer. However, the dark …

We present new astrometric and polarimetric observations of flares from Sgr A* obtained
with GRAVITY, the near-infrared interferometer at ESO's Very Large Telescope …

We propose a new test of strong-field general relativity (GR) based on the universal
interferometric signature of the black hole photon ring. The photon ring is a narrow ring …

Simulated images of a black hole surrounded by optically thin emission typically display two
main features: a central brightness depression and a narrow" photon ring" consisting of …

Motivated by (i) more and more interest in strong gravitational lensing by supermassive
black holes due to the achievement of EHT observations,(ii) the ongoing popular topic on …

We study the strong gravitational lensing effect around rotating black holes in different
gravity theories. By calculating the deflection angle of strong gravitational lensing, we …