When I photographed Kip Thorne at his home in Pasadena in late 2022, his study was filled with models of warped spacetime and black holes, intricate diagrams of gravitational waves, and props from Interstellar, the film he helped bring to life. Ideas he had spent decades exploring appeared throughout the room as objects we could look at and handle. His wife, Carolee Winstein, joined us.
At one point, he and Carolee slipped into matching black leather biker jackets. It was the kind of moment I imagined Feynman would have enjoyed. Here was someone who had spent much of his life contemplating the fundamental structure of the universe, enjoying the chance to play a little for the camera.
Thorne had spent most of his career at Caltech, where he held the Richard P. Feynman Professorship of Theoretical Physics. “It can be a lot,” he said with a knowing smile, “having your chair named after a friend.” The name carried a personal history as well as a professional distinction.
For decades, Thorne had worked toward the direct detection of gravitational waves, the ripples in spacetime predicted by Einstein’s general theory of relativity. The effect reaching Earth would be extraordinarily small. Finding it required turning a theoretical possibility into an instrument sensitive enough to register something almost beyond measurement.
That instrument was LIGO, the Laser Interferometer Gravitational-Wave Observatory. At sites in Washington and Louisiana, laser beams traveled along perpendicular arms, each four kilometers long. A passing gravitational wave would stretch one arm and compress the other, changing their relative lengths by a tiny fraction of a proton’s width.
Thorne helped establish the theoretical foundations for the search, calculating what the waves might reveal about their sources and helping determine how to distinguish a signal from noise. Rainer Weiss developed the detector concept, and Barry Barish led the project through crucial stages of construction and development. A large collaboration of scientists and engineers made the experiment possible.
On September 14, 2015, a signal reached both detectors. It had traveled for about 1.3 billion years, carrying evidence of two black holes spiraling together and merging. The instruments recorded the final moments of that collision as a brief rising signal. Astronomers could now study events through the gravitational waves they produced, opening a new way to investigate objects that emit no light.
Thorne, Weiss, and Barish received the 2017 Nobel Prize in Physics for their contributions to LIGO and the observation of gravitational waves.
Sitting in his study that day, I kept thinking about the distance between an equation and a discovery. Thorne had spent years working out what these events might look like in the data, long before an instrument could detect them. Now those signals were arriving, bringing new questions about black holes and neutron stars. He seemed as curious as ever.
Outside, the light over Pasadena had softened into evening. He glanced at one of the models on his desk, fingers lightly tracing the curve of a black hole’s event horizon.
