This graduate/research level book describes our present knowledge of protons and neutrons, the particles which make up the nucleus of the atom. Experiments using high energy electrons, muons and neutrinos reveal the proton as being made up of point-like constituents, quarks. The strong forces which bind the quarks together are described in terms of the modern theory of quantum chromodynamics (QCD), the â€~glue' binding the quarks being mediated by new constituents called gluons. Larger and new particle accelerators probe the interactions between quarks and gluons at shorter distances. The understanding of this detailed substructure and of the fundamental forces responsible is one of the keys to unravelling the physics of the structure of matter. This book will be of interest to all theoretical and experimental particle physicists.

One of the main challenges in nuclear and particle physics in the last 20 years has been to understand how the proton's spin is built up from its quark and gluon constituents. Quark models generally predict that about 60% of the proton's spin should be carried by the spin of the quarks inside, whereas high energy scattering experiments have shown that the quark spin contribution is small - only about 30%. This result has been the underlying motivation for about 1000 theoretical papers and a global program of dedicated spin experiments at BNL, CERN, DESY and Jefferson Laboratory to map the individual quark and gluon angular momentum contributions to the proton's spin, which are now yielding exciting results. This book gives an overview of the present status of the field: what is new in the data and what can be expected in the next few years. The emphasis is on the main physical ideas and the interpretation of spin data. The interface between QCD spin physics and the famous axial U(1) problem of QCD (eta and etaprime meson physics) is also highlighted. Book jacket.

Understanding of protons and neutrons, or "nucleons"â€"the building blocks of atomic nucleiâ€"has advanced dramatically, both theoretically and experimentally, in the past half century. A central goal of modern nuclear physics is to understand the structure of the proton and neutron directly from the dynamics of their quarks and gluons governed by the theory of their interactions, quantum chromodynamics (QCD), and how nuclear interactions between protons and neutrons emerge from these dynamics. With deeper understanding of the quark-gluon structure of matter, scientists are poised to reach a deeper picture of these building blocks, and atomic nuclei themselves, as collective many-body systems with new emergent behavior. The development of a U.S. domestic electron-ion collider (EIC) facility has the potential to answer questions that are central to completing an understanding of atoms and integral to the agenda of nuclear physics today. This study assesses the merits and significance of the science that could be addressed by an EIC, and its importance to nuclear physics in particular and to the physical sciences in general. It evaluates the significance of the science that would be enabled by the construction of an EIC, its benefits to U.S. leadership in nuclear physics, and the benefits to other fields of science of a U.S.-based EIC.

Intended for readers with some prior knowledge of condensed-matter physics, this text emphasises the basic physics behind spontaneous structural changes in crystals. Starting with the relevant thermodynamic principles, the author discusses the nature of order variables and their collective motion in a crystal lattice. He also goes on to describe experimental methods for modulated crystal structures and gives examples of structural changes in representative systems. Both a graduate text and reference work.

Dramatic progress has been made in all branches of physics since the National Research Council's 1986 decadal survey of the field. The Physics in a New Era series explores these advances and looks ahead to future goals. The series includes assessments of the major subfields and reports on several smaller subfields, and preparation has begun on an overview volume on the unity of physics, its relationships to other fields, and its contributions to national needs. Nuclear Physics is the latest volume of the series. The book describes current activity in understanding nuclear structure and symmetries, the behavior of matter at extreme densities, the role of nuclear physics in astrophysics and cosmology, and the instrumentation and facilities used by the field. It makes recommendations on the resources needed for experimental and theoretical advances in the coming decade.

This book gives a simplified account of a new fundamental theory of physics. It is based on two postulates (or laws) and from these are derived a set of Field Equations. The solutions of these equations account for many of the features of modern physics. These solutions lead to the prediction of Newton's laws of motion and gravitation, Coulomb's law and electromagnetism, and the prediction of the values of the gravitational constant and the charge on the electron which are close to the measured values. They also lead to a formula for Plank's constant, and to SchrOdinger's equation and the basis for quantum mechanics. Particles are not points. Structures are proposed for the proton, neutron, electron, electron neutrino, muon, pion and kaons. The theory provides an account of the up, down, strange, charm and bottom quarks and the W^A and Z particles. The book is mathematical, but simplified as much as possible to make the book accessible to a wide range of readers.

The Journal on Advanced Studies in Theoretical and Experimental Physics, including Related Themes from Mathematics