Ronald Drever, co-founder of LIGO, has died

Ronald Drever, the mercurial Scottish physicist who played a leading role in developing the world’s first successful gravitational wave detectors—the Laser Interferometer Gravitational-wave Observatory (LIGO)—died yesterday. His passing came less than 18 months after LIGO physicists spotted gravitational waves—ripples in space itself—set off when two massive black holes spiraled into each other. Drever, 85, had suffered from dementia.

“He was one of the most creative physicists I’ve known,” says Kip Thorne, a theorist at the California Institute of Technology (Caltech) in Pasadena, who, along with Drever and Rainer Weiss, a physicist at the Massachusetts Institute of Technology in Cambridge, founded the LIGO collaboration in 1984. “He could see things quickly and intuitively that would take me hours to understand through mathematical calculations.”

Born in Renfrewshire, U.K., Drever earned his doctorate at the University of Glasgow in the United Kingdom in 1959 and then continued to work there. In 1970 he began working in the emerging field of trying to detect gravitational waves. In 1979, Thorne helped recruit Drever to Caltech to launch its program into gravitational-wave research.

Drever’s career in LIGO would prove a rocky one. In the beginning, he and Weiss, who had sketched out the idea for LIGO in 1972, did not see eye to eye. So Drever, Weiss, and Thorne jointly directed the project as a troika. That arrangement ended in 1987, when the National Science Foundation demanded a single director on the project and Caltech brought in Rochus “Robbie” Vogt. Drever and Vogt would clash, and in 1992 Vogt dismissed Drever from the project.

Nevertheless, Drever made “crucial” contributions to the design of LIGO, Thorne says. “Without them I don’t think we’d be here today with the discovery of gravitational waves.” LIGO consists of twin optical instruments called interferometers in Livingston, Louisiana, and Hanford, Washington, each in the shape of an enormous L with arms 4 kilometers long. Light bounces back and forth between large mirrors at the ends of each arm, and physicists use an optical phenomenon called interference to compare the lengths of the arms and detect the stretching of space.

According to Thorne, Drever’s contributions include making each arm of an interferometer a so-called Fabry-Pérot cavity that resonates with light, much as an organ pipe resonates with sound, recycling light in the interferometer to boost its power, and feeding the signal back into the device in a way that makes it more tunable. Weiss says Drever was remarkably imaginative and creative. “He thought in pictures,” Weiss says. “Many of the ideas in LIGO that make it sensitive enough to detect gravitational wave derived from his pictures.”

Weiss says that Drever could be difficult to work with, but Thorne says that “most of the time I found him delightful to have dinner or a conversation with. … He was a very good friend.”

In spite of his decline, Drever was aware of the LIGO discovery, Thorne says. In the past year, Drever, Thorne, and Weiss have received numerous awards, including the Kavli Prize in Astrophysics, which was awarded in early September 2016 in Oslo. After the ceremony, Thorne stopped to visit Drever in his nursing home in Edinburgh. “That was one of his best days in the last year, I was told [by his family],” Thorne says. “He was able to remember and we reminisced about working on LIGO, and he clearly understood that the discovery had been made and was pleased.”