This is the second of two volumes on the genesis of quantum mechanics in the first quarter of the 20th century. It covers the period 1923-1927. After covering some of the difficulties the old quantum theory had run into by the early 1920s as well as the discovery of the exclusion principle and electron spin, it traces the emergence of two forms of the new quantum mechanics, matrix mechanics and wave mechanics, in the years 1923-27. It then shows how the new theory took care of some of the failures of the old theory and put its successes on a more solid basis. Finally, it shows how in 1927 the two forms of the new theory were unified, first through statistical transformation theory, then through the Hilbert space formalism. This volume provides a detailed analysis of the classic papers by Heisenberg, Born, Jordan, Dirac, De Broglie, Einstein, Schrödinger, von Neumann and other authors. Drawing on the correspondence of these and other physicists, their later reminiscences and the extensive secondary literature on the "quantum revolution", this volume places these papers in the context of the discussions out of which modern quantum mechanics emerged. It argues that the genesis of modern quantum mechanics can be seen as the construction of an arch on a scaffold provided by the old quantum theory, discarded once the arch could support itself.

This is the second of two volumes on the genesis of quantum mechanics in the first quarter of the 20th century. It covers the period 1923-1927. After covering some of the difficulties the old quantum theory had run into by the early 1920s as well as the discovery of the exclusion principle and electron spin, it traces the emergence of two forms of the new quantum mechanics, matrix mechanics and wave mechanics, in the years 1923-27. It then shows how the new theory took care of some of the failures of the old theory and put its successes on a more solid basis. Finally, it shows how in 1927 the two forms of the new theory were unified, first through statistical transformation theory, then through the Hilbert space formalism. This volume provides a detailed analysis of the classic papers by Heisenberg, Born, Jordan, Dirac, De Broglie, Einstein, Schrödinger, von Neumann and other authors. Drawing on the correspondence of these and other physicists, their later reminiscences and the extensive secondary literature on the “quantum revolution”, this volume places these papers in the context of the discussions out of which modern quantum mechanics emerged. It argues that the genesis of modern quantum mechanics can be seen as the construction of an arch on a scaffold provided by the old quantum theory, discarded once the arch could support itself.

Constructing Quantum Mechanics is the first of two volumes on the genesis of quantum mechanics. It covers the key developments in the period 1900-1923, which provided the scaffold on which the arch of modern quantum mechanics was built. This volume traces the early contributions by Planck,Einstein, and Bohr to the theories of black-body radiation, specific heats, and spectroscopy, all showing the need for drastic changes to the physics of their day. It examines the efforts by Sommerfeld and others to provide a new theory, now known as the old quantum theory. After some strikinginitial successes (explaining the fine structure of hydrogen, X-ray spectra, and the Stark effect), the old quantum theory ran into serious difficulties (failing to provide consistent models for helium and the Zeeman effect) and eventually gave way to matrix and wave mechanics.The book breaks new ground, both in its treatment of the work of Sommerfeld and his associates, and also in its offering of new perspectives on classic papers by Planck, Einstein, and Bohr. Throughout this volume, the authors provide detailed reconstructions of the central arguments and derivationsof the physicists involved, allowing for a full and thorough understanding of the key principles.

This two-volume book is on the genesis of quantum mechanics. The first volume covers the key developments in the period 1900-1923, which provided the scaffold on which the arch of modern quantum mechanics was built. This volume traces the early contributions by Planck, Einstein, and Bohr to the theories of black-body radiation, specific heats, and spectroscopy, all showing the need for drastic changes to the physics of their day. It examines the efforts by Sommerfeld and others to provide a new theory, now known as the old quantum theory. After some striking initial successes (explaining the fine structure of hydrogen, X-ray spectra, and the Stark effect), the old quantum theory ran into serious difficulties (failing to provide consistent models for helium and the Zeeman effect) and eventually gave way to matrix and wave mechanics. The second volume provides detailed analysis of the classic papers by Heisenberg, Born, Jordan, Dirac, De Broglie, Einstein, Schrödinger, von Neumann and other authors. Drawing on the correspondence of these and other physicists, their later reminiscences and the extensive secondary literature on the "quantum revolution," this volume places these papers in the context of the discussions out of which modern quantum mechanics emerged. It argues that the genesis of modern quantum mechanics can be seen as the construction of an arch on a scaffold provided by the old quantum theory, discarded once the arch could support itself.

Constructing Quantum Mechanics is the first of two volumes on the genesis of quantum mechanics. This volume traces the early contributions by Planck, Einstein, and Bohr, all showing the need for drastic changes to the physics of their day. It examines the efforts by Sommerfeld and others to develop a new theory, now known as the old quantum theory. After some striking successes, this theory ran into serious difficulties and ended up serving as the scaffold on which the arch of modern quantum mechanics was built. This volume breaks new ground, both in its treatment of the work of Sommerfeld and his associates, and by offering new perspectives on classic papers by Planck, Einstein, Bohr, and others. Paying close attention to both primary and secondary sources, Constructing Quantum Mechanics provides an in-depth analysis of the heroic struggle to come to terms with the wealth of mostly spectroscopic data that eventually gave us modern quantum mechanics.

Note: The three volumes are not sequential but rather independent of each other and largely self-contained.The reader of Simple Systems is not expected to be familiar with the material in Basic Matters, but should have the minimal knowledge of a standard brief introduction to quantum mechanics with its typical emphasis on one-dimensional position wave functions. The step to Dirac's more abstract and much more powerful formalism is taken immediately, followed by reviews of quantum kinematics and quantum dynamics. The important standard examples (force-free motion, constant force, harmonic oscillator, hydrogen-like atoms) are then treated in considerable detail, whereby a nonstandard perspective is offered wherever it is deemed feasible and useful. A final chapter is devoted to approximation methods, from the Hellmann-Feynman theorem to the WKB quantization rule.