The man who won the 2015 Nobel Prize for Physics for the groundbreaking research he conducted at Sudbury Neutrino Observatory said he considered the late Stephen Hawking a friend.
Art McDonald said he met Hawking, who passed away March 14 at the age of 76, about six times.
That includes the British theoretical physicist's two visits, in 1998 and 2012, to the Sudbury underground research facility at Creighton Mine, now known as SNOLAB.
“He was an inspirational person, someone that I had met on a number of occasions, and talked about a variety of things with him,” said McDonald, a professor emeritus of physics at Queen's University.
“It's really sad to see that he's passed.”
Hawking lived with a rare early-onset, slow-progressing form of ALS that gradually paralyzed him over the years. After the loss of his speech, he was still able to communicate through a speech-generating device.
McDonald said it was possible to converse with Hawking, although it took awhile, especially by his 2012 visit. By then, he was operating his speech-generating device with a single cheek muscle.
“At that point, he was just as interested,” he said. “He was asking questions about the experiments we have underground.”
Despite Hawking's communication difficulties, his sense of humour shone through.
McDonald relates an anecdote about his 1998 visit to Sudbury, when Hawking was referencing a phenomenon called cosmic microwave background, which has a temperature of about three degrees above absolute zero (-274 C).
“Or as he said, almost as cold as Sudbury in the wintertime,” McDonald said.
His sense of adventure was also still intact, he said. During his 2012 visit to the Sudbury research facility, he was breathing with the aid of a battery-operated ventilator.
Due to his medical fragility, the lift carrying Hawking down to SNOLAB was operated at half speed for the first half of the journey. After stopping to make sure he was OK, Hawking asked to go full speed.
Asked if Hawking is one of the brightest scientific minds in history, McDonald said he was definitely “an extremely valuable contributor to our understanding of the universe.”
His scientific works include the theoretical prediction that black holes emit radiation, often called Hawking radiation. Astronomers have now “very clearly” detected two black holes colliding, McDonald said.
Hawking enjoyed visiting facilities such as SNOLAB as he saw the benefits of experimental physics in proving the theories put forward by theoretical physicists such as himself.
“Our relationship with Stephen was really a partnership,” McDonald said. “From that point of view, we're missing a partner now.”
Hawking also did a lot of work to popularize science, he said.
His 1988 best-seller “”A Brief History of Time,” in which he presented the best scientific ideas on the history, nature and fate of the universe for public consumption, catapulted him into the mainstream and has sold more than 10 million copies.
Hawking also appeared on popular television shows including “Star Trek: The Next Generation,” “The Simpsons” and “Big Bang Theory.”
“I think there are probably many young people have been inspired in science by what Stephen Hawking has said and done,” McDonald said.
Hawking's accomplishments are all the more remarkable, given his contributions were mostly made after he was diagnosed with ALS, under extremely difficult circumstances, he said.
“I think he's a Paralympian of science,” McDonald said. “He behaves like the wonderful athletes who overcome their difficulties in order to accomplish things in their field.”