Ways to test the quantum nature of gravity

At the Chapel Hill conference in 1957, Richard Feynman posed the question of whether the gravitational field generated by a mass in spatial superposition is the superposition of the gravitational fields produced by the mass at two separate locations, or if it behaves differently. He leaned towards the first option, while acknowledging the possibility that quantum mechanics might fail under certain conditions. Despite over 60 years of intensive theoretical and experimental research, this question remains unanswered. We examine the current state of theoretical and experimental studies and propose new ideas for testing the quantum nature of gravity.