Bohr and Planck helped shaped the cultural landscape of the world today. Now their work is available here in a digestible, pocket format for the modern reader. A concise, uncluttered edition for the modern reader, with a new introduction. Quantum Theory contains two foundational works of quantum research from the early years of the 20th Century, representing breakthroughs in science that radically altered the landscape of modern knowledge: Quantum Theory of Line-Spectra by Niels Bohr and The Origin and Development of the Quantum Theory by Max Planck. The FLAME TREE Foundations series features core publications which together have shaped the cultural landscape of the modern world, with cutting-edge research distilled into pocket guides designed to be both accessible and informative.

Presenting a variety of topics that are only briefly touched on in other texts, this book provides a thorough introduction to the techniques of field theory. Covering Feynman diagrams and path integrals, the author emphasizes the path integral approach, the Wilsonian approach to renormalization, and the physics of non-abelian gauge theory. It provides a thorough treatment of quark confinement and chiral symmetry breaking, topics not usually covered in other texts at this level. The Standard Model of particle physics is discussed in detail. Connections with condensed matter physics are explored, and there is a brief, but detailed, treatment of non-perturbative semi-classical methods. Ideal for graduate students in high energy physics and condensed matter physics, the book contains many problems,which help students practise the key techniques of quantum field theory.

Starting from basic principles, the book systematically covers both Heisenberg and Schrödinger realizations of quantum mechanics (in this order). It provides excellent didactic introduction to the essential principles and treats recent concepts such as entanglement and decoherence. The book gives the background needed to understand quantum cryptography, teleportation and computation, and it is especially suitable for introducing the spin. This second edition includes a more friendly presentation to Hilbert spaces, and more practical applications e.g. scanning tunneling microscope (potential barrier).

Assuming a background in basic classical physics, multivariable calculus, and differential equations, A Concise Introduction to Quantum Mechanics provides a self-contained presentation of the mathematics and physics of quantum mechanics. The relevant aspects of classical mechanics and electrodynamics are reviewed, and the basic concepts of wave-particle duality are developed as a logical outgrowth of experiments involving blackbody radiation, the photoelectric effect, and electron diffraction. The Copenhagen interpretation of the wave function and its relation to the particle probability density is presented in conjunction with Fourier analysis and its generalization to function spaces. These concepts are combined to analyze the system consisting of a particle confi ned to a box, developing the probabilistic interpretation of observations and their associated expectation values. The Schrödinger equation is then derived by using these results and demanding both Galilean invariance of the probability density and Newtonian energy-momentum relations. The general properties of the Schrödinger equation and its solutions are analyzed, and the theory of observables is developed along with the associated Heisenberg uncertainty principle. Basic applications of wave mechanics are made to free wave packet spreading, barrier penetration, the simple harmonic oscillator, the Hydrogen atom, and an electric charge in a uniform magnetic fi eld. In addition, Dirac notation, elements of Hilbert space theory, operator techniques, and matrix algebra are presented and used to analyze coherent states, the linear potential, two state oscillations, and electron diffraction. Applications are made to photon and electron spin and the addition of angular momentum, and direct product multiparticle states are used to formulate both the Pauli exclusion principle and quantum decoherence. The book concludes with an introduction to the rotation group and the general properties of angular momentum.

There are many excellent books on quantum theory from which one can learn to compute energy levels, transition rates, cross sections, etc. The theoretical rules given in these books are routinely used by physicists to compute observable quantities. Their predictions can then be compared with experimental data. There is no fundamental disagreement among physicists on how to use the theory for these practical purposes. However, there are profound differences in their opinions on the ontological meaning of quantum theory. The purpose of this book is to clarify the conceptual meaning of quantum theory, and to explain some of the mathematical methods which it utilizes. This text is not concerned with specialized topics such as atomic structure, or strong or weak interactions, but with the very foundations of the theory. This is not, however, a book on the philosophy of science. The approach is pragmatic and strictly instrumentalist. This attitude will undoubtedly antagonize some readers, but it has its own logic: quantum phenomena do not occur in a Hilbert space, they occur in a laboratory.

Informative review considers the development of fundamental commutation relations for angular momentum components and vector operators. Additional topics include the computation and application of matrix elements of scalar, vector, and tensor operators for deriving useful relations in the theory of magnetic moments, electric quadruple moments, and dipole transition probabilities.

Unravel the fabric of reality as these visionary physicists revolutionize our understanding of the subatomic realm. Planck's groundbreaking concept of quantized energy and Bohr's daring atomic model challenge classical notions, unveiling a universe of uncertainty and limitless potential. This captivating journey delves into the paradoxes and probabilities that define our existence, shaping modern science and philosophy. Join the quantum pioneers on a thrilling intellectual adventure that probes the very essence of existence and invites you to question the nature of reality itself. Explore quantum pioneers Planck and Bohr's revolution in subatomic understanding. Unveil a universe of uncertainty and limitless potential in the subatomic realm. Delve into paradoxes and probabilities that shape modern science and philosophy. Join an intellectual adventure questioning the very essence of existence. A captivating journey into the fabric of reality and the nature of existence.