Gravity's ghost

by H. M. Collins

In theory, at least, gravitational waves do exist. Scientists tell us we are constantly bathed in gravitational radiation, which is generated when stars explode or collide, and a portion of their mass becomes energy that ripples out like a disturbance on the surface of a serene pond. But unfortunately no gravitational wave has ever been directly detected, even though the search has lasted more than forty years. That's why, when a sudden burst of energy was detected recently by the giant laser Interferometer Gravitational Observatory, scientists were both cautious and optimistic. Could this...