In the early morning hours of Wednesday, March 14th, the extraordinary Cambridge University cosmologist and theoretical physicist, Stephen Hawking, died peacefully at his home in Cambridge, England. It was 55 years after doctors had given him just three years to live.
The New York Times aptly spoke of Professor Hawking as having “roamed the cosmos from his wheelchair.” That wheelchair was where he spent most of his adult life, having been diagnosed at the age of 21 with amyotrophic lateral sclerosis, or ALS. He often said: “I want to show that people need not be limited by physical handicaps, if they are not disabled in spirit.”
Hawking spoke of the goal of his intellectual roaming as a simple one: “a complete understanding of the universe, why it is as it is, and why it exists at all.” His contribution to our effort to achieve that understanding was enormous, with profound discoveries on the nature of gravity and the properties of black holes. In his work with mathematician Sir Roger Penrose, he showed that Einstein’s theory of relativity implied that space and time originated in the Big Bang and would end in black holes.
Professor Hawking also became something of a pop culture icon, appearing on episodes of the Simpsons and Star Trek, and interviewed by comedian John Oliver. He notably took on the mission of making intelligible to lay readers some of the most complex scientific phenomena. His 1988 bestseller “A Brief History of Time: From the Big Bang to Black Holes” was translated into 35 languages and sold over 10 million copies.
Hawking sought a complete theory of the universe that he believed would be comprehensible to everyone. “Then,” he said, “we shall all, philosophers, scientists and just ordinary people, be able to take part in the discussion of why it is that we and the universe exist.”
“If we find the answer to that,” he continued, “it would be the ultimate triumph of human reason—for then we would know the mind of God.”
Indeed, his deep and expansive intellectual efforts to probe the outer reaches of human knowledge well-bordered on the spiritual, although he disavowed any belief in God or an afterlife.
“We are just an advanced breed of monkeys on a minor planet of a very average star,” said Hawking. “But we can understand the Universe. That makes us something very special.”
Professor Hawking spoke widely about what he considered grave threats to survival of the human race, telling the BBC in 2016: “Although the chance of a disaster to planet Earth in a given year may be quite low, it adds up over time, and becomes a near certainty in the next thousand or 10,000 years.”
In particular, he had fears that artificial intelligence could train itself to match or go beyond human beings, and he worried about the possibility of nations stumbling into nuclear war.
Perhaps most pressing for Professor Hawking was global warming, which he saw as one of the greatest threats to the planet. He expressed great concern about Donald Trump’s decision to pull America out of the Paris Climate Agreement, telling BBC News in 2017: “We are close to the tipping point where global warming becomes irreversible. Trump’s action could push the Earth over the brink, to become like Venus, with a temperature of 250 degrees, and raining sulphuric acid.”