Using a selection of key experiments performed over the past 30 years or so, we present a discussion of the strikingly counter-intuitive phenomena of the quantum world that defy explanation in terms of everyday "common sense" reasoning, and we provide the corresponding quantum mechanical explanations with a very elementary use of associated formalism.

Most, but certainly not all, of the experiments we describe are optical experiments involving a very small number of photons (particles of light). We begin with experiments on the wave-particle duality of electrons, proceed to experiments on the particle nature of light and single photon interference, delayed choice experiments and interaction-free detection, then go on to experiments involving the interference of two photons, quantum entanglement and Bell's Theorem, quantum teleportation, large-scale quantum effects and the divide between the classical and quantum worlds, addressing the question as to whether or not there is such a divide.

Contents

1. Physics Fundamentalism

2. The Duality of Particles and Waves: The Split Personality of Electrons

3. The Duality of Particles and Waves: Photons

4. More Fun with Photons: Photon-Splitting and its Uses

5. Entanglement and Non-Locality: Spooky Actions at a Distance

6. Quantum Information, Quantum Cryptography, and Quantum Teleportation

7. Schrödinger's Cat and Leggett's SQUID: Quantum Effects on a Large Scale?

8. Quantum Philosophy

Appendix A: A Quantum Mechanics Timeline

Appendix B: Quantum Mechanics Experiments for Undergraduates

Review

... the agreeable style and exceptional clarity of the writing makes this book a great pleasure to read ... the value of the book is above all in its comprehensible accounts of some very important and subtle experimental work, accompanied by excellent diagrammatic illustrations of the relevant apparatus. I have not encountered a better exposition of these, and can heartily recommend the book on this basis.

― Peter J. Bussey, Contemporary Physics

An instructive and entertaining read - an excellent example of what 'popular science for scientists' should be. [...] It gives a balanced and up-to-date account of fascinating quantum phenomena well beyond the double-slit experiment and Schrödinger's cat paradox. It also advocates a more relaxed approach. Quantum mechanics is weird, but not that weird.

― Nature Physics

The burgeoning fields of quantum computing, information processing and simulation develop rapidly as a consequence of theoretical insight and technological developments. The latter have enabled us to take single atoms or ions and count single photons, and many of the thought experiments discussed in earlier treatments of quantum physics have now been conducted in laboratories. This lucid account by Gerry and Bruno presents a mature discussion of the link between the microscopic quantum and the macroscopic classical worlds and will be useful for professional physicists, students and the educated layman.

― Ifan Hughes, Durham University

Gerry and Bruno succeed in introducing the quantum world in a readable but not oversimplified way. Their engaging and original account will particularly satisfy those who find popular texts on quantum mechanics lacking in technical detail. The Quantum Divide will leave readers understanding Feynman's quote with its original intent - not as an admission of defeat but as an invitation to the fascinating world of quantum physics.

― Dan Browne, Science

Highly recommended.

― M. Dickinson, CHOICE

To understand quantum information is to understand the mathematics describing it; without the mathematics you can have only the haziest picture of what the field is all about. In The Quantum Divide, Christopher Gerry, a theoretical physicist, and Kimberley Bruno, a school teacher and vice principal, have done an impressive job in cutting the necessary mathematics down to the absolute minimum, below what I previously thought was possible... An unusual feature of The Quantum Divide is that the authors do not content themselves with theory but always describe relatively simple experiments that demonstrate the expected behaviour.

― Jonathan Jones, Physics World

Book Description

Discusses how and where one can draw the border between the quantum and classical worlds, or indeed whether a border needs to be drawn at all.

About the Author

Christopher Gerry is Professor of Physics at Lehman College, The City University of New York, where his areas of research include theoretical quantum optics, quantum information theory, quantum metrology and sensing, and group theoretical methods in quantum optics and quantum theory in general.

Kimberley Bruno is Vice Principal of Williamsburg High School for Architecture and Design, Brooklyn, New York.