The Meaning of Quantum Theory: A Guide for Students of Chemistry and Physics

This book covers pretty much the same ground as Gribbins "In Search of Schrodingers Cat", but does so in a more mathematical manner. The math is not overly complex, it does not go beyond algebra, but does use very complicated notation systems (including Dirac's bracket notation). The reader should be familiar with the concept of an operator and not be frightened by the sight of partial differential equations, although none are actually solved. The book is aimed at students of Chemistry and Physics, but it is not a textbook per se, but rather an adjunct to a quantum theory text. This book is about the meaning of quantum theory, rather than about solving specific quantum problems. It focuses on the implications of the various interpretations of quantum theory. It not only goes into the standard Copenhagen interpretation (developed by Niels Bohr and colleagues) and the objections to it raised by Einstein and others, but also goes into several other interpretations, such as Einstein's hidden variable idea, DeBroglie's pilot waves and Bohm's quantum potentials. Baggott not only develops these other ideas, but also shows where many have been abandoned by their developers or proved to be inconsistent with quantum theory and experimental data. By using some math the book Baggott is able to derive the Schridinger wave equation is a very simple manner. This derivation comes from Schrodingers own notebooks and is much simpler than the more sophisticated one that Schrodinger used in his paper describing the wave equation. Baggott also shows where the uncertainty principle comes from and why it is inherent in the mathematics of wave and matrix mechanics because it is a feature of all non-commuting operators. In my opinion the derivation of the wave equation and this analysis of the uncertainty principle are alone worth the price of the book. Baggott also goes into the EPR thought experiment, derives Bell's inequality and describes in some detail the various tests for the EPR experiment and Bell's inequality. Much of this material is also included in "In Search of Schrodingers Cat", but because no math is included, Gribbin's discussion is not as detailed or complete as Baggott's. (This is not a criticism of Gribbin's book, as it is aimed at a more general audience.) Baggott's book a great choice for someone studying quantum mechanics, but is probably beyond those with an insufficient background in mathematics. I recommend Gribbins "In Search of Schrodingers Cat" (see my review of this book for more details on it) for those who want a non-mathematical treatment of this subject.

I have a fascination for books on the meaning of quantum theory. Many target the layman and dispense with mathematics. Others assume the reader is adept at applying both wave mechanics and matrix mechanics to quantum problems. Published by Oxford University Press, "The Meaning of Quantum Theory", strikes a good balance that is ideal for undergraduate students of physics and chemistry, and is especially useful as a companion for a formal text on quantum theory. The author, Jim Baggott, combines his experience as a freelance science writer with his skill as a respected lecturer in physical chemistry. In 1989 he was awarded the Marlow Medal from the Faraday Division of the Royal Society of Chemistry for his research contributions in chemical kinetics and spectroscopy. Baggott is an exceptional writer and I enjoy reading sections at random. I have twice read his book and probably will do so again.About quantum theory Baggott says, "For the first time, students are taught about a theory which they have to accept and which they have to learn how to apply, but which they cannot be expected to be told its meaning." Baggott argues that beneath the mathematical formalism of quantum mechanics, there exists an interpretation, and a philosophy, that warrants investigation.The first chapter (40 pages) offers a historical overview of the early development of quantum theory that is probably familiar to many readers. Chapter 2 (35 pages), titled "Putting it into Practice", differentiates Baggott's work from many others. We learn about operator algebra, and then we encounter experimental evidence that we must either use non-commuting matrices, or non-commuting operators, to describe position-momentum relationships in quantum physics. Baggott then carefully introduces the underlying postulates of quantum physics (and the mathematical formulation) as described by John von Neumann. We learn about complementary observables, the Dirac bracket notation, state vectors and eigenfunctions, and the usefulness of projection amplitudes. A substantial section is devoted to the Pauli exclusion principal, the polarization properties of photons, measurement operators, and the collapse of the wave function, all topics that are discussed later in the context of experimental results.After 75 pages of preparation, Baggott asks "What Does it Mean"?, the title of chapter 3. Chapter 4 is "Putting it to the Test", and Chapter 5 is "What are the Alternatives?". A reader that skimmed the mathematical discourse in chapter 2 would still find the last three chapters intriguing, although some sections might be heavy going."The Ghost in the Atom: A Discussion of the Mysteries of Quantum Physics" by Davies and Brown is non-mathematical, but offers, nevertheless, an insightful look at alternative interpretations of quantum theory - standard interpretation (Copenhagen interpretation), conscious observer, parallel universes, hidden variables, and a statistical view - that dovetails rather well wit

This book concentrates more on the philosophical aspects of quantum theory rather than formalism and problem solving, though some simple and easy to follow derivations are presented that give real insights into the guts of the theory, which will help a reader who goes on to pursue quantum theory in greater detail. The historical debate between the positivists and realists during the theories development is presented in a very readable and entertaining way. A very well written and researched book that you will be glad you read.

For those interested in modern physics, you could do far worse than read The Meaning of Quantum Theory. This is by far the most intelligable and complete look at Quatum Theory that I have come across. Bagott has written this book for the technically litterate, but has avoided using mathematics for anything other than illustration of some of the finer points of the theory. Whether you have a degree in the physical sciences or not, you will probably find that this book make Quantum Theory as clear as it can be. Having read it at the same time I was taking an undergraduate quantum mechanics course, I found this book helped me make sense of the mathematics. Students who have been, are being, or expect to be exposed to the theory should buy this book and read it; everything will make much more sense.

FINALLY!! Of all the Quantum books I have seen, this book is the most helpful and clear book I have ever read on this subject. I have a difficult time understanding Quantum from the math that most books use to describe it; this book gives historical background and philosophy of the theory which makes it not only understandable, but EASY.