The Old Quantum Theory explains how the classical laws were modified by Planck, Einstein, Rutherford, Bohr, and other contributors to account for atomic phenomena, comprising the development of quantum theory from its start at the very end of the 19th century until the beginning of the 20th century. This book begins by discussing Planck's discovery of his radiation law, followed by Einstein's introduction to quanta. Next is a description of the Rutherford model of the atom and Bohr's postulates, which are confirmed by the Franck-Hertz experiment. This selection concludes with a description of how Bohr's theory could explain the main features of the atomic spectra. A brief summary of other important developments in the period are also elaborated. This publication is beneficial to students and researchers conducting work on the history of quantum mechanics from the 1900s to the development of wave mechanics.

The Old Quantum Theory

This is an exceptionally accessible, accurate, and non-technical introduction to quantum mechanics. After briefly summarizing the differences between classical and quantum behaviour, this engaging account considers the Stern-Gerlach experiment and its implications, treats the concepts of probability, and then discusses the Einstein-Podolsky-Rosen paradox and Bell's theorem. Quantal interference and the concept of amplitudes are introduced and the link revealed between probabilities and the interference of amplitudes. Quantal amplitude is employed to describe interference effects. Final chapters explore exciting new developments in quantum computation and cryptography, discover the unexpected behaviour of a quantal bouncing-ball, and tackle the challenge of describing a particle with no position. Thought-provoking problems and suggestions for further reading are included. Suitable for use as a course text, The Strange World of Quantum Mechanics enables students to develop a genuine understanding of the domain of the very small. It will also appeal to general readers seeking intellectual adventure.

This book presents a history of the correspondence principle from a new perspective. The author provides a unique exploration of the relation between the practice of theory and conceptual development in physics. In the process, he argues for a new understanding of the history of the old quantum theory and the emergence of quantum mechanics. The analysis looks at how the correspondence principle was disseminated and how the principle was applied as a research tool during the 1920s. It provides new insights into the interaction between theoretical tools and scientific problems and shows that the use of this theoretical tool changed the tool itself in a process of transformation through implementation. This process, the author claims, was responsible for the conceptual development of the correspondence principle. This monograph connects to the vast literature in the history of science, which analyzed theoretical practices as based on tacit knowledge, skills, and calculation techniques. It contributes to the historical understanding of quantum physics and the emergence of quantum mechanics. Studying how physicists used a set of tools to solve problems, the author spells out the ‟skillful guessing” that went into the making of quantum theoretical arguments and argues that the integration and implementation of technical resources was a central driving force for the conceptual and theoretical transformation in the old quantum theory.

This book offers a fresh perspective on some of the central experimental and theoretical works that laid the foundations for today's quantum mechanics: It traces the theoretical and mathematical development of the hypotheses that put forward to explain puzzling experimental results; it also examines their interconnections and how they together evolved into modern quantum theory. Particular attention is paid to J.J. Thomson's atomic modeling and experiments at the Cavendish Laboratory, Max Planck's struggle to explain the experimental results of Heinrich Rubens and Ferdinand Kurlbaum, as well as the path leading from Louis de Broglie’s ideas to the wave theory of Erwin Schrödinger. Combining his experience in teaching quantum mechanics with his interest in the historical roots of the subject, the author has created a valuable resource for understanding quantum physics through its history, and a book that is appreciated both by working physicists and historians.