Minyong Guo

The heart of the Milky Way, the object Sagittarius A*, might turn out not to be a black hole, but its perfect cosmic counterfeit — a boson star. Data from the infrared interferometer GRAVITY were compared with models of twelve such stars — giant scalar clumps — and the Bayesian verdict could not tel

A covariant approach has been developed, showing that light in the gravitational "storm" of merging black holes alters its polarization, tracing the damped melody of the ringdown. Numerical simulations based on Kerr perturbation theory confirm: an achromatic rotation of ~10 degrees is a direct impri

The stronger the scalar field around a black hole, the more distorted its shadow. New simulations reveal that at extreme values, the shadow fractures into crescent-shaped shards.