He then sketched out ideas for what became a modest-sized prototype detection device. Over the decades, his ideas grew into the massive Laser Interferometer Gravitational-Wave Observatory, or LIGO — a project operated by MIT and the California Institute of Technology. In an interview for an MIT publication , Dr. Weiss recalled wondering: “What’s the simplest thing I can think of to show these students that you could detect the influence of a gravitational wave?” Nearly 60 years ago, Rainer Weiss was asked to teach a course in general relativity at the Massachusetts Institute of Technology. He struggled with how to...