How does gravity work at the particle level? The question has stumped physicists since the two bedrock theories of
general relativity (Albert Einstein’s equations envisioning gravity as curves in the geometry of space-time) and
quantum mechanics (equations that describe particle interactions) revolutionized the discipline about a century ago.
One challenge to solving the problem lies in the relative weakness of gravity compared with the strong, weak and electromagnetic forces that govern the subatomic realm. Though gravity exerts an unmistakable influence on macroscopic objects like orbiting planets, leaping sharks and everything else we physically experience, it produces a negligible effect at the particle level, so physicists can’t test or study how it works at that scale.
