The End of the Certain World: The Life and Science of Max Born

  • Nancy Thorndike Greenspan
Basic Books: 2005. 320 pp. $26.95 0738206938, 0470856637 | ISBN: 0-738-20693-8

Max Born was one of the founding fathers of quantum mechanics — indeed, he coined its name even before his assistant, Werner Heisenberg, gave birth to the theory with a breakthrough paper in the summer of 1925. But Born never received the recognition he so richly deserved, a gap that this book should help to fill.

Born was the professor of theoretical physics in Göttingen from 1921 until his dismissal by the Nazis in 1933. In those days that meant he could really shape the content and quality of the research programme. This he did superbly, assembling a group of brilliant youngsters and focusing them on atomic physics.

By 1925, Born had already realized that the puzzles posed by atomic spectra should be attacked by focusing on transition probabilities. He had also reached the seminal view that the theory should concentrate on what is in principle observable, and not on classical but unobservable constructs, such as electronic orbits, which figured prominently in the ‘old quantum theory’. These insights were essential conceptual ingredients in Heisenberg's paper, which first set out, albeit in a skeletal and rather opaque form, the algebraic scheme of the nascent theory. It was Born who recognized that this scheme was matrix algebra. And it was Born who first wrote down the commutation rule, which specifies by how much xp differs from px, where x and p are the matrices corresponding to the coordinate and momentum of a particle. This equation is the key to the mathematical structure of quantum mechanics, and was engraved on Born's tombstone at his request.

Overlooked: while his colleagues quickly won Nobel prizes, Max Born received little recognition. Credit: AKG-IMAGES

Before the end of 1925, Born, Heisenberg and Pascual Jordan had developed these first steps at amazing speed into an almost complete theory — as had the incredibly gifted Cambridge student Paul Dirac working independently in splendid isolation. By 1933, Nobel prizes had been given to Heisenberg and Dirac, and also to Erwin Schrödinger, whose equivalent wave-mechanical formulation only began to appear in January 1926. But Born was left out. More unfair still, Niels Bohr and Heisenberg subsequently gave him little recognition for his role in developing the widely accepted interpretation of quantum mech-anics. Finally, in 1954, long after Born had been forced to leave Germany for Britain, he did receive a Nobel prize.

The prize recognized, at long last, Born's discovery of the statistical interpretation of the wave function. He was the first to recognize the profound departure from classical concepts of causality that quantum mechanics implies. In particular, he recognized that although the Schrödinger equation describes a continuous and causal evolution, it nevertheless makes only statistical predictions about observable events. This was before Heisenberg's discovery of the uncertainty principle and Bohr's formulation of complementarity, the essential ingredients in the Copenhagen interpretation. Bohr, Heisenberg and their entourage did not properly acknowledge this fact for a very long time.

In The End of the Certain World, Nancy Thorndike Greenspan paints a rich picture of the social, political and intellectual scene in which Born rose to the academic stratosphere from his birth in 1882 into a prosperous Jewish family. He was not a wunderkind. On the contrary, at the age at which the prodigies Dirac, Heisenberg and Wolfgang Pauli had become legendary scientists, Born had only earned his doctorate in applied mathematics with a thesis on an unexciting topic, and was yet to realize that cutting-edge theoretical physics would be his forte.

As the book recounts, the German physics community took a long time to recognize the talents of this creative and productive man — quite why has been something of a mystery. The intellectual calibre of the cast that populates the book during the early years of Born's career is stunning to a degree that is not adequately recognized or explained, except in the case of Einstein. Born was a modest man of exceptional but not overwhelming intellectual power (unlike the ever-present David Hilbert), and would have had good reason to be intimidated. He was in a similar position to an outstanding Florentine artist whose work remains well known to this day, but who had to make his way in the company of Michelangelo and Leonardo da Vinci. Born compensated for whatever handicap he felt by becoming something of a workaholic, which over time helped him to master an enormous range of physics and produce a prodigious quantity of research papers and splendid texts — from the elementary to his classic treatise on optics.

As the book explains, Born did not have an easy youth psychologically. As a mature man he was often not sturdy enough, physically and mentally, to handle the load that he imposed on himself. This was compounded by his sometimes shaky marriage to a fragile and not always faithful woman. That he produced so much despite all this is remarkable. The portrait that emerges is of a refined intellectual of the highest ethical standards, unwilling or unable to advocate effectively on his own behalf — even accepting his wife's demand that their children should not attend the Nobel ceremonies. Although he was a refugee from Nazi Germany, he was profoundly disturbed to see his beloved pure physics spawning nuclear weapons in the hands of some of his most talented students: Robert Oppenheimer, Edward Teller, Victor Weisskopf and the spy Klaus Fuchs.

So does this book fill what is a serious gap in the history of twentieth-century physics? In contrast to the other great figures in the quantum revolution, Born's personality has never been described in any depth, and this part of the gap is filled exceptionally well. As for Born's science, the job is done for the physicist, who can apply well-informed opinions to grade the significance of the people and discoveries described. But other readers would have benefited from an account of Born's work that did a better job of separating the wheat from the chaff.

All the book's readers would have benefited had the editor insisted that we do not need to know the names of all those Alpine hotels the Borns visited, what they ate there, and a barrage of other details. This mass of minutae often produces a haze that could make it hard for readers to see what is most exceptional and long-lasting among Born's many achievements. Nevertheless, there is no question that any future work on Born will find this book to be an indispensable study of this major figure in one of the most profound transformations in the history of science.