Stephen Hawking: A Biography, by Kristine Larsen (Amherst, N.Y.: Prometheus Books, 2007, ISBN 978-159102-9574-0) 215 pp. Paper $16.95.
The famous cosmologist Stephen Hawking had an extraordinary career ahead of him, or so it seemed in his twenty-first year. Acknowledged as brilliant by his fellow physics students at Oxford, he was troubled only by occasional lapses from normal muscular coordination that sometimes led to a tumble, events generally more embarrassing than painful. Nevertheless, the persistent recurrence of these incidents persuaded his parents that a medical diagnosis was needed. The diagnosis was devastating. Stephen Hawking was suffering from Amyotrophic Lateral Sclerosis (ALS), known in America as Lou Gehrig’s Disease. He was told that he probably had only two more years to live.
In Stephen Hawking: A Biography, astrophysicist Kristine Larsen has written a moving account of a world-famous cosmologist who this year celebrated his sixty-sixth birthday and who continues to astonish the science world with highly original work on the origins of the universe and the nature of the almost inscrutable black holes. That he has lived so long with a condition normally fatal within a few years, has courageously overcome several progressive stages of the disease while continuing to be highly productive in his work, and has been able to find joy in life is a tribute to the human spirit in the face of adversity that Larsen records very well.
This biography gives approximately equal treatment to Hawking’s achievements as a scientist and to his personal life. However, Larsen’s accounts of Hawking’s approach to science may be even more interesting to the intelligent nonscientist than the highly esoteric results of his work. Like the doyen of twentieth-century science, Albert Einstein, Hawking was initially far more interested in visualizing physical phenomena than in representing them mathematically. Only later, when he realized that a mastery of the relevant mathematics was essential to obtaining solutions to the problems that challenged him, did he acquire the needed skills, often assisted by mathematical colleagues. It was at that point that his work truly came to the attention of the science world.
Larsen illustrates several examples of how Hawking approaches a problem in this spirit. The first discovery that brought him fame may have been that black holes radiate. A black hole is a “singularity” associated with a collapsed mass that prevents anything within what is called “the event horizon” from escaping because of the strength of its gravitational field. Hawking had already shown that these objects are characterized by only three physical parameters: mass, electrical charge (if any), and angular momentum. (The nature of the constituent material does not matter and cannot be known.) It was initially assumed that black holes could not radiate but only be discovered by their gravitational effects on nearby bodies. However, Hawking showed that the creation of a particle-antiparticle pair just outside the event horizon of a black hole permits the apparent creation of a new particle in the observable universe with one particle observable and the other vanishing back into the black hole. Because the energy for the pair creation (a well-known quantum-mechanical process addressed by the probabilistic nature of quantum physics) has to come from somewhere, and the black hole is the only source in this case, the black hole gradually loses energy and in time (a very long time) radiates away!
If the nonscientist reader remains puzzled by the previous paragraph, which summarizes as good a description of some of Hawking’s black-hole work as this reviewer has read, he or she can appreciate the difficulty of transmitting to the general public the results of this remarkable scientist’s research. As Larsen notes, Hawking himself realized this difficulty following the publication of his first popular book. A Brief History of Time was a spectacular publishing success and brought the author well-deserved royalties that eased his complicated life considerably. However, the book was still generally considered a “challenging read” for all but the specialist, and, according to Larsen, it may have been honored more by coffee-table appearances than by elevated discussions among the uninitiated. Not surprisingly, one concept the book treated that many readers found hard to grasp was “imaginary time.” Hawking addressed this communications problem with a later book, The Illustrated Brief History of Time, and the even-more successful and still-more accessible The Universe in a Nutshell, which won a coveted award for popular science writing in 2002.
The author gives a sympathetic account of Hawking’s personal life to supplement her brief but excellent descriptions of his primary scientific achievements. These sections of the book exhibit great respect for the triumph of the scientist’s life in adjusting to his illness without becoming a hagiography, which Hawking would not want. Hawking was twice married and twice divorced. He fathered three children by his first wife who have gone on to successful careers of their own. He has thoroughly enjoyed the company of many celebrities, ranging from film and rock stars to prominent politicians like Al Gore, whose 2000 presidential campaign Hawking supported. He has appeared on many television programs and traveled extensively, giving scientific talks to large audiences of world-class specialists. He has also used his fame to speak out frankly on ma-jor world issues, such as nuclear weapons control and environmental degradation.
Larsen’s biography is admirably succinct, covering the highlights of Hawking’s life in 172 fact-filled, well-written pages. The book is supplemented by four appendices for those who wish a brief tutorial on (A) General Relativity and Cosmology, (B) The Laws of Thermodynamics and Black Holes, (C) Inflationary Cosmology (consistent with several observations made recently), and (D) AdS/CFT Correspondence (very brief comments on the latest attempts of theoretical physicists to produce a “theory of everything”). There is also a glossary of scientific terms to which even this reviewer, who is an astrophysicist, found necessary to turn on occasion. I would recommend this book to any reader interested in the excitement of scientific research as practiced by one of its foremost and most courageous practitioners.