‘Subtle is the Lord…’: The Science and the Life of Albert Einstein
by Abraham Pais
Oxford University Press, 552 pp., $25.00
Albert Einstein was not only respected and admired by his fellow scientists as probably the greatest physicist of this century but he also achieved extraordinary fame among people who did not have the least idea of his work. What did he accomplish? Although he is most widely known as the discoverer of the theory of relativity, he made other vital contributions which are far less well known but which, by themselves, would have placed him in the front ranks of physicists. The most important of these was his part in creating the quantum theory. He gained the Nobel prize for this, not for his work on relativity.
Abraham Pais’s book is thus particularly valuable as the first thorough study in one accessible volume of all of Einstein’s major contributions to science. A physicist who knew Einstein when they were both at the Institute for Advanced Study at Princeton, Pais presents each phase of Einstein’s work against the background of Einstein’s previous ideas and those of his predecessors. In each case he tries, as far as possible, to reconstruct Einstein’s train of thought. To do so, of course, he has to describe the technical aspects of each problem, and it will be difficult for any reader without some acquaintance with theoretical physics to follow his account. For those qualified to read it, however, his book is remarkably clear as well as authoritative.
The breadth of Einstein’s vision and his originality were shown in his work of 1905, when, as a twenty-six-year-old technical expert, third class, in the Swiss patent office in Bern, he wrote five important papers, all carefully discussed in Pais’s book. Two of these established what is now called the special theory of relativity. This starts from the long-established fact that a state of uniform motion cannot be distinguished from being at rest. It is a familiar fact that the passenger in a fast airplane experiences no sensation of being in motion, unless air turbulence or a change of direction causes the motion to be nonuniform. But it was then thought that by watching the speed of light one might be able to tell the difference. Physicists believed that light consisted of vibrations of a hypothetical, all-pervasive medium, the “ether,” and that by observing the way light travels, we could discover whether we were at rest, or moving, relative to this ether. This seems reasonable if we think of sound waves. If we were sitting on the tail of a plane, our voices shouting to a friend on top of the cockpit would seem to be traveling slowly, because they had to go against the rush of air experienced by the plane; the sound of our friend’s voice would reach us faster than normal sound. On a supersonic plane the sound of our voices would not reach the man in front at all.
We are all participating in the motion of the earth around its axis and in its orbit about …