Dr Jiannis Pachos is a reader in theoretical physics at the University of Leeds who knew Stephen Hawking, who has died aged 76.
He first met him as a PhD student in Durham when Professor Hawking gave a talk at a conference in the city.
“Watching him coming on stage in his wheelchair and communicating through a computer, which takes a lot of effort, was a humbling experience,” he said.
Like countless other budding young scientists he was inspired by Professor Hawking’s work.
“When I was a young student he made me want to become a physicist even more, so he inspired me from a young age.”
Dr Pachos later spent three years at Cambridge University working in the same department as Prof Hawking.
“He was very easygoing, he would join people for lunch and he was very approachable. You had to be patient to communicate with him so it might take several minutes to get a reply with a simple ‘yes’ or ‘no’, never mind a complicated sentence,” he said.
“He was a very daring physicist who wasn’t afraid to make mistakes.
“He liked to have bets with other famous physicists about the big questions in science and if he lost or got it wrong he would publicise it, which says something about the person as well as the scientist and made him even more likeable.
“He worked on very difficult and complicated topics that requires knowledge of detailed physics and yet he was able to do this and explain it in a way that people could understand.”
Dr Pachos believes Professor Hawking’s legacy will last for centuries to come. “He’s up there at the top there’s no question about it. He’s one of the giants not only of modern times but of all time.”