This 8 August 2019 video from the USA says about itself:
For the past 23 years Andrea Ghez, professor of physics and astronomy at UCLA, has been collecting data on stars that orbit black holes. She found that their motion provided an opportunity to test the fundamental laws of physics. “We asked how gravity behaves near a supermassive black hole and whether Einstein’s theory is telling us the full story. ”Einstein’s 1915 theory of general relativity holds that what we perceive as the force of gravity arises from the curvature of space and time. “In Newton’s version of gravity, space and time are separate, and do not co-mingle; under Einstein, they get completely co-mingled near a black hole,” she said. Ghez’s research is the most detailed study ever conducted into the supermassive black hole and Einstein’s theory of general relativity.