Prof T-Y Wu is not only an eminent physicist with an encyclopedic knowledge, but also a motivational teacher and an influential policy maker in science and technology. The young Wu was inspired by Prof Y-T Yao, whose course on modern physics sparked an interest that burned during a long and productive career. Among Wu's achievements are 14 books and more than 120 papers covering subjects from atomic and molecular physics to plasmas and gases to atmospheric physics to relativity theory. Even at the age of 90 he remains active, publishing papers and lecturing on physics.Prof Wu feels grateful that he had the opportunity to educate a group of extremely talented students and, in particular, to discover T D Lee's remarkable talent. Although creative talent is no doubt a product of nature, it must also be nurtured. Prof Wu has played a crucial role for an entire generation of physicists in China and has won great respect from former students such as C N Yang, T D Lee, K Huang, and countless others. Prof Wu's love of physics and his dedication in teaching and research will always be remembered.

A Broader View of Relativity shows that there is still new life in old physics. The book examines the historical context and theoretical underpinnings of Einstein''s theory of special relativity and describes Broad Relativity, a generalized theory of coordinate transformations between inertial reference frames that includes Einstein''s special relativity as a special case. It shows how the principle of relativity is compatible with multiple concepts of physical time and how these different procedures for clock synchronization can be useful for thinking about different physical problems, including many-body systems and the development of a Lorentz-invariant thermodynamics. Broad relativity also provides new answers to old questions such as the necessity of postulating the constancy of the speed of light and the viability of Reichenbach''s general concept of time. The book also draws on the idea of limiting-four-dimensional symmetry to describe coordinate transformations and the physics of particles and fields in non-inertial frames, particularly those with constant linear accelerations. This new edition expands the discussion on the role that human conventions and unit systems have played in the historical development of relativity theories and includes new results on the implications of broad relativity for clarifying the status of constants that are truly fundamental and inherent properties of our universe. Sample Chapter(s). Chapter 1: Introduction and Overview (326 KB). Contents: The Historical and Physical Context of Relativity Theory: Space, Time and Inertial Frames; On the Right Track: Voigt, Lorentz, and Larmor; The Novel Creation of the Young Einstein; A Broader View of Relativity: The Central Role of the Principle of Relativity: Relativity Based Solely on the Principle of Relativity; Experimental Tests I & II; Group Properties of Taiji Relativity and Common Relativity; Common Relativity and Quantum Mechanics; Extended Relativity: A Weaker Postulate for the Speed of Light; The Role of the Principle of Relativity in the Physics of Accelerated Frames: The Principle of Limiting Lorentz and Poincar(r) Invariance; Physical Properties of Spacetime in Accelerated Frames; Dynamics of Classical and Quantum Particles in Constant-Linear-Acceleration Frames; Group and Lie Algebra Properties of Accelerated Spacetime Transformations; Appendices: Systems of Units and the Development of Relativity Theories; Quantum Electrodynamics in Both Linearly Accelerated and Inertial Frames; and other papers. Readership: Researchers in the field of relativity theory and advanced undergraduate students as a supplementary text.

A Broader View of Relativity shows that there is still new life in old physics. The book examines the historical context and theoretical underpinnings of Einstein's theory of special relativity and describes Broad Relativity, a generalized theory of coordinate transformations between inertial reference frames that includes Einstein's special relativity as a special case. It shows how the principle of relativity is compatible with multiple concepts of physical time and how these different procedures for clock synchronization can be useful for thinking about different physical problems, including many-body systems and the development of a Lorentz-invariant thermodynamics. Broad relativity also provides new answers to old questions such as the necessity of postulating the constancy of the speed of light and the viability of Reichenbach's general concept of time. The book also draws on the idea of limiting-four-dimensional symmetry to describe coordinate transformations and the physics of particles and fields in non-inertial frames, particularly those with constant linear accelerations. This new edition expands the discussion on the role that human conventions and unit systems have played in the historical development of relativity theories and includes new results on the implications of broad relativity for clarifying the status of constants that are truly fundamental and inherent properties of our universe.

This collection of papers presents ideas and problems arising over the past 100 years regarding classical and quantum gravity, gauge theories of gravity, and spacetime transformations of accelerated frames. Both Einstein''s theory of gravity and the YangOCoMills theory are gauge invariant. The invariance principles in physics have transcended both kinetic and dynamic properties and are at the very heart of our understanding of the physical world. In this spirit, this book attempts to survey the development of various formulations for gravitational and YangOCoMills fields and spacetime transformations of accelerated frames, and to reveal their associated problems and limitations. The aim is to present some of the leading ideas and problems discussed by physicists and mathematicians. We highlight three aspects: formulations of gravity as a YangOCoMills field, first discussed by Utiyama; problems of gravitational theory, discussed by Feynman, Dyson and others; spacetime properties and the physics of fields and particles in accelerated frames of reference. These unfulfilled aspects of Einstein and YangOCoMills'' profound thoughts present a great challenge to physicists and mathematicians in the 21st century."

This book shows how one can combine Yang-Mills gauge symmetry and effective Einstein-Grossmann metric tensors to tackle physical problems at microscopic, macroscopic and super-macroscopic length scales in inertial frames, including the late-time accelerated cosmic expansion due to baryon masses and charges. The combination of gauge symmetry and effective metric tensor provides a framework and leads to an alternative dynamics of cosmic expansion based on quantum Yang-Mills gravity at a super-macroscopic limit. Together with cosmological principle, one can investigate and derive expanding scale factors, the age of the universe, the cosmic redshift, and the Hubble recession velocity with an upper limit. All these discussions are based on inertial frames with operationally defined space and time coordinates.

YangOCoMills gravity is a new theory, consistent with experiments, that brings gravity back to the arena of gauge field theory and quantum mechanics in flat space-time. It provides solutions to long-standing difficulties in physics, such as the incompatibility between Einstein''s principle of general coordinate invariance and modern schemes for a quantum mechanical description of nature, and Noether''s OCyTheorem IIOCO which showed that the principle of general coordinate invariance in general relativity leads to the failure of the law of conservation of energy. YangOCoMills gravity in flat space-time appears to be more physically coherent than conventional gravity in curved space-time. The problems of quantization of the gravitational field, the operational meaning of space-time coordinates and momenta, and the conservation of energy-momentum are all resolved in YangOCoMills gravity.The aim of this book is to provide a treatment of quantum YangOCoMills gravity, with an emphasis on the ideas and evidence that the gravitational field is the manifestation of space-time translational symmetry in flat space-time, and that there exists a fundamental space-time symmetry framework that can encompass all of physics, including gravity, for all inertial and non-inertial frames of reference.

The purposes of this book are (1) to explore and expound relativity physics and four-dimensional symmetry from the logically simplest viewpoint by making one single postulate instead of two; and (2) to indicate the simplest generalization of the Lorentz transformation in order to cope with frames with constant linear accelerations. The fundamentally new ideas of the first purpose are developed on the basis of the term paper of a Harvard physics undergraduate. They lead to an unexpected affirmative answer to the long-standing question of whether it is possible to construct a relativity theory without postulating the constancy of the speed of light and retaining only the first postulate of special relativity. This question was discussed in the early years following the discovery of special relativity by many physicists, including Ritz, Tolman, Kunz, Comstock and Pauli, all of whom obtained negative answers. Furthermore, the new theory of relativity indicates the truly universal and fundamental constants in physics, and provides a broad view of relativistic physics beyond special relativity. It substantiates the view and sheds light on the understanding that the four-dimensional symmetry framework can accommodate many different concepts of physical time, including common time and Reichenbach's general concept of time. This logically simplest viewpoint of relativity allows a natural extension of the physics of particles and fields from inertial frames to noninertial frames in which the speed of light is not constant. New predictions in physics resulting from this new viewpoint are discussed. The book is based on papers by the author and his collaborators in Physics Letters A, Nuovo Cimento B, and Physical Review A and D.