In Quantum, Manjit Kumar, the founding editor of the interdisciplinary journal Prometheus and co-author of Science and the Retreat From Reason, attempts to provide an authoritative narrative of the history of quantum physics and those that shaped it. Kumar starts with Max Planck and Albert Einstein at the turn of the twentieth century and leads the reader through all the major players, and many others, involved in the intellectual upheaval that was/is quantum physics.
In 1905, Einstein suggested that light be considered a particle, as opposed to a wave, in an attempt to explain the phenomenon of ejected electrons from materials that had light incident upon them (the so-called photoelectric effect), going against the wisdom of the day. This insight set off a revolution in physics; a revolution that required the reworking of all the rules and scientific prejudices of the atomic and subatomic universe.
This book is described as “the definitive popular book on quantum
theory”' and claims to “set the science in the context of the great upheavals of the modern age”. But it is and does neither of these things.
Quantum is essentially a write-up of Kumar’s extensive biographical investigations into the scientists that shaped quantum theory. The level of biographical detail, interesting anecdotes and the awareness of how the various people, research groups and experiments fit into the history of quantum theory is impressive – the main reason to have Quantum on your bookshelf. However, it is also one of a number of reasons why this book fails in its claimed raison d’etre.
If the science takes a back seat, then it cannot be a popular science book. By choosing to concentrate on the individuals, Quantum fails to describe the science in a satisfactory manner. In the early part of the book, the setting of the scene by working through each scientist in turn leads to a jumping back and forth in time in the narrative, which makes it hard to follow. When Kumar decides to write about the science, as opposed to the individuals, his descriptions are generally lazy, giving an impression that he has failed to grasp what is necessary to attempt a project such as this. The correct strategy would be to make the science the centrepiece, especially early on, bringing in personalities and anecdotes to create a rounded discussion. This way, the debate between Einstein and Niels Bohr later in the text can be placed in context, with a solid description of quantum theory as its base.
His somewhat lethargic approach to the descriptions are made manifest by the use of algebraic forms to make his points. This is bad style in a popular science book unless no description is possible without them. They appear in Quantum through a lack of effort. Even with the equations, Kumar is inconsistent. He often explains the easiest pieces of mathematics in more detail than the harder extracts!
There is a further problem with regards the content and the pace. Quantum has the subtitle “Einstein, Bohr and the great debate about the nature of reality”. The claim that “Kumar’s centrepiece is the conflict between Einstein and Bohr over the nature of reality and the soul of science” is misleading. The concentration on the biographical details mean that this “debate” is not reached until page 263 of 360. An interjection on the war, and the book finishing on John Stewart Bell’s inequalities, means that very little time is devoted to the intellectual sparring of Bohr and Einstein.
Kumar's failure to discuss the science adequately earlier in the book reduces the debate down to a mere report of what went on. Quantum is an opportunity lost; it is a book caught in two minds. It has ambitions to be a popular science book, but the emphasis on biography lets it down. Any masterpiece on quantum theory has to put the science in the foreground and use the history as a narrative tool. Quantum gets this the wrong way around and consequently does not achieve what it sets out to do, and, more importantly, what it claims to do. This was the most frustrating feature of the book which, at times, projected a kind of arrogance.
Books describing the history of scientific revolutions are always welcome, which, with some tinkering, this book could have been. Readers searching for a lay text describing in detail quantum theory and the debate over reality can do much better with the now almost twenty-five years old, In Search of Schrodinger's Cat, by John Gribbin.
Reviewed by Chris Orme