My Brief History
9
MARRIAGE
WHEN WE RETURNED FROM CALTECH IN 1975, WE knew that the stairs in our house would now be too difficult for me. The college by then appreciated me rather more, so it let us have a ground-floor apartment in a large Victorian house it owned. (The house has now been demolished and replaced by a student accommodation block bearing my name.) The apartment was in gardens maintained by the college gardeners, which was nice for the children.
I initially felt rather low on returning to England. Everything seemed so parochial and restricted there compared to the can-do attitude in America. At the time, the landscape was littered with dead trees killed by Dutch elm disease and the country was beset by strikes. However, my mood lifted as I saw success in my work and was elected, in 1979, to the Lucasian Professorship of Mathematics, a post once held by Sir Isaac Newton and Paul Dirac.
Our third child, Tim, was also born in 1979 after a trip to Corsica, where I was lecturing at a summer school. Thereafter Jane became more depressed. She was worried I was going to die soon and wanted someone who would give her and the children support and marry her when I was gone. She found Jonathan Jones, a musician and organist at the local church, and gave him a room in our apartment. I would have objected, but I too was expecting an early death and felt I needed someone to support the children after I was gone.
With my family after the christening of our third child, Tim (illustration credit 9.1)
I continued to get worse, and one of the symptoms of my progressing illness was prolonged choking fits. In 1985, on a trip to CERN (European Organization for Nuclear Research) in Switzerland, I caught pneumonia. I was rushed to the cantonal hospital and put on a ventilator. The doctors at the hospital thought I was so far gone that they offered to turn off the ventilator and end my life, but Jane refused and had me flown back by air ambulance to Addenbrooke’s Hospital in Cambridge. The doctors there tried hard to get me back to how I had been before, but in the end they had to perform a tracheotomy.
Before my operation my speech had been getting more slurred, so only people who knew me well could understand me. But at least I could communicate. I wrote scientific papers by dictating to a secretary, and I gave seminars through an interpreter who repeated my words more clearly. However, the tracheotomy removed my ability to speak altogether. For a time, the only way I could communicate was to spell out words letter by letter by raising my eyebrows when someone pointed to the right letter on a spelling card. It is pretty difficult to carry on a conversation like that, let alone write a scientific paper. However, a computer expert in California named Walt Woltosz heard of my plight and sent me a computer program that he had written, called Equalizer. This allowed me to select words from a series of menus on the screen by pressing a switch in my hand. I now use another of his programs, called Words Plus, which I control by a small sensor on my glasses that responds to my cheek movement. When I have built up what I want to say, I can send it to a speech synthesizer.
At first I just ran the Equalizer program on a desktop computer. Then David Mason, of Cambridge Adaptive Communication, fitted a small personal computer and a speech synthesizer to my wheelchair. My computers are now supplied by Intel. This system allows me to communicate much better than I could before, and I can manage up to three words a minute. I can either speak what I have written or save it on disk. I can then print it out or call it back and speak it sentence by sentence. Using this system, I have written seven books and a number of scientific papers. I have also given a number of scientific and popular talks. They have been well received, which I think is due in large part to the quality of the speech synthesizer, made by Speech Plus.
One’s voice is very important. If you have a slurred voice, people are likely to treat you as mentally deficient. This synthesizer was by far the best I had heard because it varies the intonation and didn’t speak like one of the Daleks from Doctor Who. Speech Plus has since gone into liquidation and its speech synthesizer program has been lost. I now have the last three remaining synthesizers. They are bulky, use a lot of power, and contain chips that are obsolete and can’t be replaced. Nevertheless, by now I identify with the voice and it has become my trademark, so I won’t change it for a more natural-sounding voice unless all three synthesizers break.
When I came out of the hospital I needed full-time nursing care. At first I felt my scientific career was over and all that would be left to me would be to stay at home and watch television. But I soon found I could carry on my scientific work and write mathematical equations using a program called Latex, which allows one to write mathematical symbols in ordinary characters, such as $/pi$ for π.
HOWEVER, I became more and more unhappy about the increasingly close relationship between Jane and Jonathan. In the end I could stand the situation no longer, and in 1990 I moved out to a flat with one of my nurses, Elaine Mason.
We found the flat rather small for us and Elaine’s two sons, who were with us for part of the week, so we decided to move. A bad storm in 1987 had torn off the roof of Newnham College, the sole women-only undergraduate college. (The men-only colleges had all by this time admitted women. My college, Caius, which had a number of conservative fellows, was one of the last, and it was finally persuaded by the students’ exam results that it wouldn’t get good men applying unless it admitted women as well.) Because Newnham was a poor college, it had had to sell four plots of land to pay for the roof repair after the storm. We bought one of the plots and built a wheelchair-friendly house.
Elaine and I got married in 1995. Nine months later Jane married Jonathan Jones.
My wedding to Elaine (illustration credit 9.2)
My marriage to Elaine was passionate and tempestuous. We had our ups and downs, but Elaine’s being a nurse saved my life on several occasions. After the tracheotomy, I had a plastic tube in my trachea, which prevented food and saliva from getting into my lungs and was retained by an inflated cuff. Over the years the pressure in the cuff damaged my trachea and made me cough and choke. I was coughing on a flight back from Crete, where I had been at a conference, when David Howard, a surgeon who happened to be on the same plane, approached Elaine and said he could help me. He suggested a laryngectomy, which would completely separate my windpipe from my throat and remove the need for a tube with a cuff. The doctors at Addenbrooke’s Hospital in Cambridge said it was too risky, but Elaine insisted, and David Howard carried out the operation in a London hospital. That operation saved my life: another two weeks and the cuff would have worn a hole between my windpipe and my throat, filling my lungs with blood.
A few years later I had another health crisis because my oxygen levels were falling dangerously low in deep sleep. I was rushed to the hospital, where I remained for four months. I was eventually discharged with a ventilator, which I used at night. My doctor told Elaine that I was coming home to die. (I have since changed my doctor.) Two years ago I began using the ventilator twenty-four hours a day. I find it gives me energy.
With Elaine in Aspen, Colorado (above and below) (illustration credit 9.3)
(illustration credit 9.4)
A year after that I was recruited to help the university’s fund-raising campaign for its eight-hundredth anniversary. I was sent to San Francisco, where I gave five lectures in six days and got very tired. One morning I passed out when I was taken off the ventilator. The nurse on duty thought I was okay, but I would have died had not another caregiver summoned Elaine, who resuscitated me. All these crises took their emotional toll on Elaine. We got divorced in 2007, and since the divorce I have lived alone with a housekeeper.
10
A BRIEF HISTORY OF TIME
I FIRST HAD THE IDEA OF WRITING A POPULAR BOOK about the universe in 1982. My intention was partly to earn money to pay my daughter’s school fees. (In fact, by the time the book actually appeared, she was in her last year of school.) But the main reason for writing it was that I wanted to explain how far I felt we had come in our understanding of the universe: how we m
ight be near finding a complete theory that would describe the universe and everything in it.
If I was going to spend the time and effort to write a book, I wanted it to get to as many people as possible. My previous technical books had been published by Cambridge University Press. That publisher had done a good job, but I didn’t feel that it would really be geared to the sort of mass market that I wanted to reach. I therefore contacted a literary agent, Al Zuckerman, who had been introduced to me as the brother-in-law of a colleague. I gave him a draft of the first chapter and explained that I wanted it to be the sort of book that would sell in airport bookstores. He told me there was no chance of that. It might sell well to academics and students, but a book like that couldn’t break into Jeffrey Archer territory.
I gave Zuckerman a first draft of the book in 1984. He sent it to several publishers and recommended that I accept an offer from Norton, a fairly upmarket American book firm. But I decided instead to take an offer from Bantam Books, a publisher more oriented toward the popular market. Though Bantam had not specialized in publishing science books, its books were widely available in airport bookstores.
Bantam’s interest in the book was probably due to one of their editors, Peter Guzzardi. He took his job very seriously and made me rewrite the book so that it would be understandable to non-scientists such as himself. Each time I sent him a rewritten chapter, he sent back a long list of objections and questions he wanted me to clarify. At times I thought the process would never end. But he was right: it is a much better book as a result.
One of the early covers of A Brief History of Time (illustration credit 10.1)
My writing of the book was interrupted by the pneumonia I caught at CERN. It would have been quite impossible to finish the book but for the computer program I was given. It was a bit slow, but then I think slowly, so it suited me quite well. With it I almost completely rewrote my first draft in response to Guzzardi’s urgings. I was helped in this revision by one of my students, Brian Whitt.
I had been very impressed by Jacob Bronowski’s television series The Ascent of Man. (Such a sexist title would not be allowed today.) It gave a feeling for the achievement of the human race in developing from primitive savages only fifteen thousand years ago to our present state. I wanted to convey a similar feeling for our progress toward a complete understanding of the laws that govern the universe. I was sure that nearly everyone is interested in how the universe operates, but most people cannot follow mathematical equations. I don’t care much for equations myself. This is partly because it is difficult for me to write them down, but mainly because I don’t have an intuitive feeling for equations. Instead, I think in pictorial terms, and my aim in the book was to describe these mental images in words, with the help of familiar analogies and a few diagrams. In this way, I hoped that most people would be able to share in the excitement and feeling of achievement in the remarkable progress that has been made in physics in the last fifty years.
Still, even if I avoided using mathematics, some of the ideas would be difficult to explain. This posed a problem: should I try to explain them and risk people being confused, or should I gloss over the difficulties? Some unfamiliar concepts, such as the fact that observers moving at different velocities measure different time intervals between the same pair of events, were not essential to the picture I wanted to draw. Therefore I felt I could just mention them but not go into depth. But other difficult ideas were essential to what I wanted to get across.
There were two such concepts in particular that I felt I had to include. One was the so-called sum over histories. This is the idea that there is not just a single history for the universe. Rather, there is a collection of every possible history for the universe, and all these histories are equally real (whatever that may mean). The other idea, which is necessary to make mathematical sense of the sum over histories, is that of imaginary time. With hindsight, I now feel that I should have put more effort into explaining these two very difficult concepts, particularly imaginary time, which seems to be the thing in the book with which people have the most trouble. However, it is not really necessary to understand exactly what imaginary time is—just that it is different from what we call real time.
WHEN THE book was nearing publication, a scientist who was sent an advance copy to review for Nature magazine was appalled to find it full of errors, with misplaced and erroneously labeled photographs and diagrams. He called Bantam, which was equally appalled and decided that same day to recall and scrap the entire printing. (Copies of the original first edition are now probably quite valuable.) Bantam spent three intense weeks correcting and rechecking the entire book, and it was ready in time to be in bookstores by the April Fools’ Day publication date. By then, Time magazine had published a profile of me.
Even so, Bantam was taken by surprise by the demand for the book. It was on The New York Times bestseller list for 147 weeks and on the London Times bestseller list for a record-breaking 237 weeks, has been translated into 40 languages, and has sold over 10 million copies worldwide.
My original title for the book was From the Big Bang to Black Holes: A Short History of Time, but Guzzardi turned it around and changed Short to Brief. It was a stroke of genius and must have contributed to the success of the book. There have been many “brief histories” of this and that since, and even A Brief History of Thyme. Imitation is the sincerest form of flattery.
Why did so many people buy it? It is difficult for me to be sure that I’m objective, so I think I will go by what other people said. I found most of the reviews, although favorable, rather unilluminating. They tended to follow a single formula: Stephen Hawking has Lou Gehrig’s disease (the term used in American reviews) or motor neurone disease (in British reviews). He is confined to a wheelchair, cannot speak, and can only move X number of fingers (where X seems to vary from one to three, according to which inaccurate article the reviewer read about me). Yet he has written this book about the biggest question of all: where did we come from and where are we going? The answer Hawking proposes is that the universe is neither created nor destroyed: it just is. In order to formulate this idea, Hawking introduces the concept of imaginary time, which I (that is, the reviewer) find a little hard to follow. Still, if Hawking is right and we do find a complete unified theory, we shall really know the mind of God. (In the proof stage I nearly cut the last sentence in the book, which was that we would know the mind of God. Had I done so, the sales might have been halved.)
Rather more perceptive, I felt, was an article in The Independent, a London newspaper, which said that even a serious scientific work such as A Brief History of Time could become a cult book. I was rather flattered to have my book compared to Zen and the Art of Motorcycle Maintenance. I hope that, like Zen, it gives people the feeling that they need not be cut off from the great intellectual and philosophical questions.
Undoubtedly, the human interest story of how I have managed to be a theoretical physicist despite my disability has helped. But those who bought the book because of the human interest angle may have been disappointed, because it contains only a couple of references to my condition. The book was intended as a history of the universe, not of me. This has not prevented accusations that Bantam shamefully exploited my illness and that I cooperated with this by allowing my picture to appear on the cover. In fact, under my contract I had no control over the cover. I did, however, manage to persuade the publisher to use a better photograph on the British edition than the miserable and out-of-date photo used on the American edition. Bantam will not change the photo on the American cover, however, because it says that the American public now identifies that photo with the book.
It has also been suggested that many people bought the book to display on the bookcase or on the coffee table, without having actually read it. I am sure this happens, though I don’t know that it is any more so than with most other serious books. I do know that at least some people must have waded into it, because each day I get a pile of letters abou
t that book, many asking questions or making detailed comments that indicate that they have read it, even if they do not understand all of it. I also get stopped by strangers on the street who tell me how much they enjoyed it. The frequency with which I receive such public congratulations (though of course I am more distinctive, if not more distinguished, than most authors) seems to indicate that at least a proportion of those who buy the book actually do read it.
Since A Brief History of Time, I have written other books to explain science to the wider public: Black Holes, and Baby Universes, The Universe in a Nutshell, and The Grand Design. I think it is important that people have a basic understanding of science so they can make informed decisions in an increasingly scientific and technological world. My daughter, Lucy, and I have also written a series of “George” books, which are scientifically based adventure stories for children, the adults of tomorrow.
11
TIME TRAVEL
IN 1990 KIP THORNE SUGGESTED THAT IT MIGHT BE possible to travel into the past by going through wormholes. I therefore thought it would be worthwhile to investigate whether time travel is allowed by the laws of physics.
To speculate openly about time travel is tricky for several reasons. If the press picked up that the government was funding research into time travel, there would be either an outcry at the waste of public money or a demand that the research be classified for military purposes. After all, how could we protect ourselves if the Russians or Chinese had time travel and we didn’t? They could bring back Comrades Stalin and Mao. In physics circles, there are only a few of us foolhardy enough to work on a subject that some consider unserious and politically incorrect. So we disguise our focus by using technical terms, such as “particle histories that are closed,” that are code for time travel.