Study indicates that energy can be extracted from black holes A new study indicates that, someday, energy could be extracted from black holes. January 19, 2021 A remarkable prediction of Einstein's theory of general relativity -- the theory that connects space, time and gravity -- is that rotating black holes have enormous amounts of energy available to be tapped. For the last 50 years, scientists have tried to come up with methods to unleash this power. Physical Review D, physicists Luca Comisso of Columbia University and Felipe Asenjo of the Universidad Adolfo Ibáñez in Chile have found a...