Bumblebee Black Holes in Light of Event Horizon Telescope Observations

We report the existence of novel static spherical black-hole solutions in a vector-tensor gravitational theory called bumblebee gravity model which extends Einstein-Maxwell by allowing vector to nonminimally couple Ricci curvature tensor. A test strong-field regime is performed for first time using recent observations supermassive shadows galaxy M87 and Milky Way from Event Horizon Telescope Collaboration. The parameter space found largely unexcluded more experiments are needed fully bound theory.