HOWZAT

“I enjoyed having to write in a different way,” he replies. “It was quite a change from A Brief History of Time.”

I suggest that fiction can be problem-solving, albeit in a different way from science, and he replies: “It was similar in the sense that both George and Brief History were written to explain science. Children have a natural curiosity about why things are, and how they work. I know, because I’m a child myself.”

“Did it reinforce, or strain, the father-daughter relationship? Or both? Did it make you reflect on the kind of father you have been to her, in circumstances which so-called ordinary families might have difficulty imagining?”

“Working on the book brought us closer together. One of the few regrets I have is that my condition prevented me from playing with my children as much as I would have liked.”

“You must have been delighted to become a grandfather. How have you taken to the role?”

“I love children. I would have liked to have had more children, but grandchildren are the next best thing.”

All these answers are of course delivered in the imposed near-monotone of the synthesiser. It has an unfashionable downturn at the end of sentences, making it sound like a station announcement with some unusual information. He has used this voice since a life-threatening bout of pneumonia led to a tracheotomy back in 1985. One reason why he has kept the same model is that it has become recognisably his own over the years. It is part of his trademark. He knows – as did Star Trek: the Next Generation and The Simpsons, in which he made cameo appearances – that it has a certain grim hilarity. Sometimes, in public places, the little lens picks up signals from his face when he is not actually “talking”, and the voice spews out strings of nonsense with all the authority that it uses to deconstruct the universe.

We carry on: “Did you draw on your own relationship to portray the one between Eric [the scientist in the new book] and his daughter?”

“In the first draft of the book, Eric lived alone in the house next to George [the young hero]. In my childhood, or even Lucy’s, it would have been quite acceptable for a child to visit a single man living on his own. However, we were told that modern concerns meant that such visits were no longer possible. We therefore added Annie and her mother to give Eric a family. This also gave the book more interest for girls.”

Like her father, Lucy Hawking is not long divorced. She has a nine-year-old son, William, and was told, after he had been diagnosed with autism six years ago, that he would never advance beyond a mental age of two. The boy’s father is Alex Mackenzie Smith, who was a member of the UN Peace Corps in Bosnia and is now based in Africa. The marriage went wrong early on; she says that the “externals of bombed-out Sarajevo”, where they had been living, were an accurate reflection of her inner turmoil.

Three years ago, after a particularly bad patch for the Hawking family, she was in serious trouble with alcohol, having evidently self-medicated the pain of it all. It was grave enough for her to go for a four-week treatment at a clinic in Arizona. She said at the time that if she had had carried on, things were going to get worse in “an unimaginably nightmarish way”. When I ask her if she now abstains, she replies that it (the whole drinking business) is not something she wants to go into. “If you don’t mind.”

A central figure during that period was her father’s ex-wife, Elaine. She blenches at the name and says he hates having his private life discussed. Yet the allegations about Elaine were serious and public, and some of them came from Lucy herself: cuts and bruises, apparently unexplained, were found on the professor’s wasted body; he had allegedly been left out in the sun on the hottest day of the 2003 summer. The police were called in. Hawking himself said there was nothing that couldn’t be explained by his own difficult relationship with the wheelchair, and paid tribute to his then wife’s care. In March 2004, Det Supt Michael Campbell of Cambridgeshire Police concluded: “I can find no evidence to substantiate any assertion that anyone has perpetrated any criminal acts against Prof. Hawking.” The couple divorced last year.

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