Rainer Weiss

Rainer Weiss is a German-American physicist and Nobel Laureate best known for co-founding the Laser Interferometer Gravitational-Wave Observatory (LIGO), which led to the first detection of gravitational waves in 2015. Born in Berlin on September 29, 1932, Weiss was the son of a German Jewish neurologist and a Protestant actress. His father, a communist persecuted by the Nazis, fled to Prague with the help of Weiss’s maternal relatives. After the 1938 Munich Agreement, the family sought refuge in the United States, aided by a sponsorship from a St. Louis family that secured visas for Jewish professionals.

Settling in New York in 1939, Weiss attended public schools before earning a scholarship to the Columbia Grammar School. He developed a deep interest in electronics, building high-fidelity audio systems and running a small business repairing radios during high school. He began studies in electrical engineering at MIT but switched to physics after becoming disillusioned with the rigid curriculum. His undergraduate and graduate work were deeply influenced by experimentalist Jerrold Zacharias, with whom he worked on precision atomic clocks and gravitational redshift experiments.

Weiss’s early career was shaped by his involvement in atomic beam and Mössbauer effect experiments. In the 1960s, he turned to cosmology and gravitation, helping pioneer balloon-borne instruments to measure the cosmic microwave background, an effort that later culminated in the COBE satellite project. As chair of COBE’s science working group, Weiss played a key leadership role in shaping modern cosmology, although the Nobel Prize for that work went to others on the team.

His most groundbreaking achievement was developing LIGO, an ambitious effort to detect gravitational waves predicted by Einstein’s general relativity. Drawing on his earlier work in laser stabilization and interferometry, Weiss designed a prototype detector and laid the foundations for the full-scale observatory. His persistence over decades helped turn a theoretical concept into one of the most important discoveries in modern physics.

Weiss, along with Kip Thorne and Barry Barish, was awarded the 2017 Nobel Prize in Physics for this work. At its core, LIGO’s success validated a century-old prediction of general relativity and opened an entirely new field of observational astronomy.

Weiss passed away on August 26, 2025, at 92.

Weiss’s life reflects the journey of a Jewish refugee who became one of the world’s leading experimental physicists. A professor emeritus at MIT, he is widely regarded for his scientific achievements and humility, ingenuity, and dedication to hands-on science. He has two children with his wife, Rebecca, and remains deeply connected to family and the scientific community.

Source: “Rainer Weiss Biographical,” The Nobel Prize.
“Rainer Weiss ‘55 PhD ’62,” MIT.
Adrian Cho, “Meet the college dropout who invented the gravitational wave detector,” Science.org, (August 4, 2016).
Dylan Luab McClain, “Rainer Weiss, Who Gave a Nod to Einstein and the Big Bang, Dies at 92,” New York Times, (August 26, 2025).

Photo: Bengt Nyman from Vaxholm, Sweden, CC BY 2.0, via Wikimedia Commons.