Physicist Stephen Hawking has died at the age of 76, say his family.
The British theoretician was known for his work on black holes, relativity and cosmology, as well as the best-selling popular science book A Brief History of Time.
Hawking cut a striking figure in the academic world with his brilliant theories and impish sense of humour. Unlike most physicists, he also made an indelible impression on the popular imagination as an Einstein-like figure of genius with his electric wheelchair and computer-synthesised voice.
Perhaps his most famous contribution to science was the idea of Hawking radiation. By applying the ideas of quantum mechanics to the event horizon of a black hole, he came to the conclusion that black holes should not actually be entirely black. Instead, they should give off a faint glow and, unless they absorb new material, eventually evaporate away.
His most significant contribution to popular culture was A Brief History of Time, a 250-page survey of cosmology, theoretical physics and the history of the universe first published in 1988. The work has sold more than 10 million copies, though it is sometimes called “the most unread book of all time”.
In 1963, at the age of only 21, Hawking was diagnosed with motor neurone disease or amyotrophic lateral sclerosis, a degenerative condition that left him wheelchair-bound and eventually able to communicate only by typing via sensor attached to a muscle in his cheek. At the time of the diagnosis, he was given two years to live.
Fifty-five years later, after two marriages, three children, groundbreaking work on the connections between black holes, information and the big bang, and worldwide fame, Hawking died at his home in Cambridge.
In a prepared statement, his children Lucy, Robert and Tim said:
“We are deeply saddened that our beloved father passed away today. He was a great scientist and an extraordinary man whose work and legacy will live on for many years. His courage and persistence with his brilliance and humour inspired people across the world. He once said, ‘It would not be much of a universe if it wasn’t home to the people you love.’ We will miss him for ever.”