David Castelvecchi in Nature:
His death was marked by statements from scientists around the world. Astrophysicist Neil DeGrasse Tyson, the director of the Hayden Planetarium in New York City, wrote on Twitter: "His passing has left an intellectual vacuum in his wake. But it's not empty. Think of it as a kind of vacuum energy permeating the fabric of spacetime that defies measure." One of Hawking’s former students at Cambridge, theoretical physicist Raphael Bousso, told Nature that his teacher was a brilliant physicist who also excelled at communicating science to the public. “These are two distinct skills. Stephen excelled at both.” Bousso, now at the University of California at Berkeley, recalls how he had to learn to shake off his awe and relax around Hawking. “Stephen was a joyful and lighthearted person, not to be burdened by excessively respectful and convoluted interactions,” he says. The British physicist was born in Oxford in 1942. He was diagnosed with ALS when he was 21, while a doctoral student in cosmology at the University of Cambridge. Hawking first realized that something was wrong when he went ice skating with his mother one day, he recalled in a speech on his 75th birthday celebration last year. “I fell over and had great difficulty getting up,” he told the audience. “At first I became depressed. I seemed to be getting worse very rapidly.” Although physicians initially gave him just a few years to live, his disease advanced more slowly than expected. He went on to have an active career for decades, both as a theoretical physicist and as a popularizer of science. Still, Hawking progressively lost use of most of his muscles, and for the last three decades of his life was communicating almost exclusively through a voice synthesizer.
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