4 JANUARY 1992, Page 26

A man of physical and universal appeal

Tony Osman

STEPHEN HAWKING: A LIFE IN SCIENCE by Michael White and John Gribbin Ming, £16.99, pp. 304 Stephen Hawking, this fascinating book reminds us, is Britain's most famous scientist. He is not merely famous — can being famous be 'mere'? — he is also distinguished. He is the Lucasian Professor of Mathematics at Cambridge (Isaac Newton's old post), he was one of the youngest people ever to be elected a Fellow of the Royal Society and he has been awarded a long list of important academic prizes.

But it is his fame among the public that is most striking. The book he wrote for the `ordinary reader', A Short History of Time, stayed on the Sunday Times's bestseller list for more than three years and sold, in Britain alone, half a million copies in hard- back. This is almost unimaginable for a book by a theoretical physicist about his own research — it certainly wasn't imagined by the book's publishers.

One reason for this public enthusiasm is

the book's subject. It concerns itself with the most rivetting of all scientific topics, cosmology — the origin, the history, and the end of the Universe. `Was there a beginning?', cosmology asks. 'Will there be an end? How did we come to be here, inhabiting this particular planet? Is there a Plan? Does there have to be a Creator?'

There have been plenty of 'popular' books on cosmology. What makes A Short History of Time outstanding is that it is concise and

clear, and up to the minute in its science. Ideas about the origin and end of the Universe have changed dramatically in recent years, largely as a result of Stephen Hawking's research.

The public is also fascinated by Stephen Hawking himself. His body has, since his twenties, been increasingly paralysed by motor neuron disease, until it now seems only a shell supporting an incomparable mind and, as this biography shows, an attractive personality. We ordinary mortals can be distracted by a headache or an unexpected tax demand. We must be in awe of a man who can ignore so devastat- ing an illness.

White and Gribbin interweave the story of Hawking's life with that of his research in theoretical physics. Cosmology is, by definition, a theoretical science — no one is going to create a Universe to confirm a

theory — and modern cosmology is the

child of what is known — even though the major pronouncements were made more than 70 years ago — as modern physics.

Particularly, cosmology is derived from Einstein's General Theory of Relativity,

and Schrodinger's development of quantum mechanics. Hawking's particular contribution to cosmology — and to astronomy — comes from being able, in special cases, to combine the two.

The conclusions of modern cosmology tax our imaginations. This isn't surprising: as this book reminds us, the late Richard Feynman, one of the greatest theoretical physicists of all time, once said that nobody understands quantum mechanics. On the other hand, a biography of Hawking has to give a sound, though not detailed, idea of of his research. Fortunately. one of the authors, John Gribbin, has himself done research in theoretical physics, which gives him a sound start in telling us what the theories really mean.

Early in his research Stephen Hawking worked out with Roger Penrose what must be at the centre of a 'black hole'. Black

holes — collapsed stars with a density so enormous that space-time is curved around

them, trapping any kind of radiation — had been proposed as logical deduction from theory in the 1960s. Generally, scientists didn't believe they could actually exist, because the theories would lead to an unimaginable consequence. Once a star had collapsed to a black hole, it would, said the theory, continue collapsing to an unchanging — and hence timeless — point, known as a 'singularity'. This seemed impossible, and the scientists of the Sixties, in general, decided that in some way or other the theory needed revision. Hawking and Penrose devised a new mathematical approach which showed that black holes should exist, and that there must be a sin- gularity at the centre.

As well as the conceptual problems about the nature of black holes, there is the practical problem of observing them. They are, by definition, invisible. But you can't simply say that if you can't see anything in some part of the sky, it shows that there is a black hole there. Fortunately, as White and Gribbin tell us, later developments by Hawking, combining, in an awe-inspiring way, relativity and quantum mechanics, show that there are ways in which a black hole, or at least the space immediately around it, could emit X-rays. And since then, astronomers have spotted the signs of at least one black hole.

The theory of black holes is directly linked to the current theory of the origin of the Universe: the Big Bang and the forma- tion of a black hole are the same processes, running in opposite directions. At one time, Hawking thought that the evolution of the Universe might be a once-only event — starting with the Big Bang, ending as a black hole. Now, it seems, there is the possibility of continuous cycling, even the possibility of multiple Universes. White and Gribbin's book describes these developments clearly, and also leads us through other research on the nature of matter and the Universe. Scientists now hope for a grand theory, possibly involving `superstrings', that would explain every- thing, leaving scientists of the future nothing major to do. They are likely to be disappointed.

Hawking is not a dry scientist. He is a family man — upset because his illness has prevented him from playing physically with his three children. Though he now talks with a mechanical voice, he is a charming conversationalist and a witty personality.

Though living in a wheelchair, he is mis- chievous. All this is brought out in this admirable biography. It tells us, too, of his early days in Cambridge when, though the family was hard-up and living in a small, rather unsuitable house, they were part of a lively social circle. And it bears witness to the devotion of his wife Jane, from the time when she, as a student in London, commuted to Cambridge every weekend. What makes this book so rewarding is the way that the authors have blended their account of Hawking's science with that of his life, giving a picture of a remarkable scientist as a remarkable person.