Ron Drever, a physicist whose experimental ingenuity helped enable scientists to tap into the deepest levels of reality and detect vibrations of the void known as gravitational waves — space-time ripples that had been predicted by Einstein a century ago but had never before been seen — died on March 7 in Edinburgh. He was 85.
His death was announced by the California Institute of Technology, where he was an emeritus professor of physics. He had dementia, his colleagues said.
Dr. Drever was a founder, along with Kip Thorne of Caltech and Rainer Weiss of the Massachusetts Institute of Technology, of the Laser Interferometer Gravitational-Wave Observatory, or LIGO, a pair of L-shaped antennas in Washington State and Louisiana with headquarters at Caltech in Pasadena.
When scientists from the observatory announced last year that they had detected such waves from a pair of black holes that had collided a billion light years from Earth, the news mesmerized the world.
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Dr. Drever, Dr. Thorne and Dr. Weiss were awarded a slew of prestigious and lucrative prizes last summer, and few would have been surprised to see them share the Nobel in physics this fall. The Nobel is not awarded posthumously, but Dr. Thorne and Dr. Weiss would still be eligible.
Dr. Drever’s colleagues described him as a genius tinkerer, a persnickety scientific Mozart who spewed new ideas every day, sometimes leaving confusion and indecision in his wake.
“Ron was an imaginative physicist who thought primarily in pictures,” Dr. Weiss wrote in an email. “Often the pictures give him an elegant way to circumvent a lot of analytic reasoning.”
Dr. Thorne, the theorist among the three, said Dr. Drever’s approach to physics “was so different from mine: intuitive rather than analytic.”
He recalled that Dr. Drever had once come upon him struggling with a difficult calculation and solved it by drawing diagrams. “He could see things intuitively, quickly, that would take hours for me to understand in my more mundane way with mathematical calculations,” Dr. Thorne said.
Ronald William Prest Drever was born in Bishopton, Scotland, in 1931, the oldest son of George Douglas Drever, a doctor, and the former Mary Frances Matthews, a homemaker. He is survived by his younger brother, Ian, as well as a niece and two nephews.
His uncle John Richan Drever, an artist turned shipbuilder, taught him how to work with his hands and fix things. As a young man he built a working television set from war surplus items and junk in the garage. The family watched the coronation of Queen Elizabeth II on it.
Dr. Drever attended the University of Glasgow, earning a bachelor’s degree in 1953 and a Ph.D. in 1958. Continuing at Glasgow as a professor, he performed a series of experiments that established him as a virtuoso. In one, which involved old car batteries and wires strung up across his mother’s garden, he watched to see if the rotation of the Milky Way would affect the properties of atomic nuclei in a jar. The answer: Not a whit.
That experiment improved on a similar study by Vernon Hughes at Yale. Today, what is known as the Hughes-Drever experiment is considered one of the most precise tests of the equivalence principle, which states that all masses in a gravitational field fall with the same acceleration — a key notion in Einstein’s general theory of relativity.
Dr. Drever and his colleagues began to look into gravitational waves in 1970. Einstein’s theory, which ascribes gravity to the elasticity of space-time geometry, proclaimed a dynamic universe. A disturbance in such a cosmos, Einstein found, could cause space-time to shake like a mattress, producing waves or ripples that would compress space in one direction and stretch it in another as they traveled outward.
Such waves had never been seen until 1969, when Joseph Weber, a physicist at the University of Maryland, claimed to have detected them using a six-foot-long aluminum cylinder as an antenna. But nobody could replicate the claim.
Following an idea put forward by Robert Forward, a physicist at Hughes Aircraft, Dr. Drever and his colleagues set out to do it a different way, using laser beams bouncing between precisely positioned mirrors — to detect the squeeze and stretch of a passing wave.
In 1979, Dr. Thorne, a black hole maven, recruited Dr. Drever to come to Caltech to build the instrument together. Dr. Weiss was undertaking a similar effort at M.I.T. In 1984, the National Science Foundation ordered the two projects to merge.
The resulting troika, of a theorist and two experimentalists, would have their hands full, both technologically and managerially. As eventually built at a cost of $1.1 billion, the observatory would consist of a pair of L-shaped antennas — one in Washington State, the other in Louisiana — each with arms two and a half miles long. Laser light bouncing between the mirrors would keep track of their separation and record any displacement by a passing gravitational wave.
Even the most massive objects — black holes or the ultradense spinning neutron stars — would roil space only enough to move the mirrors by a fraction of the diameter of a proton, a subatomic particle too small to be seen by even the most powerful microscopes.
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One of Dr. Drever’s most important innovations, Dr. Weiss said, was to stabilize the frequency of the laser light by bouncing it back and forth in a special set of precisely situated mirrors called an optical cavity. The technique, which Dr. Weiss called “a profound and significant advance in the technology,” is now used in optical experiments that require light of a single precise wavelength — what is needed, for example, to sense a change of less than the size of a subatomic particle.
Nevertheless, progress on actually building and testing a detector was slow until the National Science Foundation decreed that the project needed a single director, not a triad. Rochus Vogt, the former provost of Caltech, was appointed to run the project in 1987.
But Dr. Drever’s intuitive style clashed with Dr. Vogt’s more analytic and deliberate approach.
“LIGO benefited from his insights and pictures in the conceptual stages” of the device, Dr. Weiss said of Dr. Drever. He added, “Later, when the instrument had to be constructed and commissioned, thorough engineering practice and careful analytic and observational efforts become paramount.”
Dr. Drever was forced out of the project in 1992 and given a separate laboratory on the Caltech campus. Two years later, Dr. Vogt was succeeded as director by Barry Barish, a Caltech particle physicist who is credited with finally managing LIGO to success.
Dr. Barish invited Dr. Drever back into the fold as a member of the LIGO Scientific Collaboration, a new group, now numbering close to 1,000 worldwide, devoted to parsing the results from LIGO and other gravitational wave experiments.
Dr. Drever retired from his Caltech professorship in 2002 but continued attending meetings of the LIGO collaboration until he began to show signs of dementia, Dr. Weiss said. He returned home to Scotland in 2010.
On Sept. 14, 2015, the newest, most sensitive version of the LIGO experiment was still undergoing troubleshooting when the sound bite heard around the cosmos raced through its mirrors: a chirp, lasting about a fifth of a second, ending in a middle C.
It was the signature of a pair of black holes spiraling faster and faster around each other at the tail end of a cosmic death dance that for a fraction of a second was unleashing more energy than all the stars in the observable universe.
The event confirmed the reality not just of gravitational waves but also of black holes — just the way Einstein’s equations had predicted them.
His family having been alerted that important news was coming, Dr. Drever was watching on television on Feb. 11 last year when his colleagues announced the discovery.
“Ronald’s face lit up,” said his niece, Anne Drever.
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