Since the dawn of mankind, observers of the sky have wondered at the sudden appearance of new stars on the seemingly unchanging heavens and, for at least 2000 years, have recorded these phenomena in their annals and archives. Even in more modern times, since the discovery of SN1885A in S Andromeda which ?gured in the important “island universe” discussions of the 1920’s, the puzzle of supernovae (SNe) has played an important role in astrophysics. Only with the seminal work of Fritz Zwicky and Walter Baade in the 1930’s did we begin to understand the di?erences between novae and SNe and the importance of SNe as the fonts of energy for the interstellar medium and as drivers of chemical evolution in galaxies. As recently as the 1940’s and 1950’s the early days of radio astronomy were heavily in?uenced by the familiar names of Cassiopeia A and Taurus A, two young supernova remnants, and two Nobel prizes have been awarded for discovery and study of a related phenomenon, pulsars. In spite of the great age of the study of SNe, since at least the Chinese records of SN185and probably earlier, the ?eld is, in fact, very young having only attracted a large devoted following since the spectacular Type II SN1987A in the Large Magellanic Cloud, the ?rst naked-eye SN in more than 400 years.

Relativistic quantum electrodynamics, which describes the electromagneticinteractions of electrons and atomic nuclei, provides the basis for modeling the electronic structure of atoms, molecules and solids and of their interactions with photons and other projectiles. The theory underlying the widely used GRASP relativistic atomic structure program, the DARC electron-atom scattering code and the new BERTHA relativistic molecular structure program is presented in depth, together with computational aspects relevant to practical calculations. Along with an understanding of the physics and mathematics, the reader will gain some idea of how to use these programs to predict energy levels, ionization energies, electron affinities, transition probabilities, hyperfine effects and other properties of atoms and molecules.

This book presents a new approach to understanding the foundation of quantum physics through the "quantum wave model" hypothesis. It addresses some of the key challenges in the current quantum theory, including the conflict between quantum mechanics and relativity, and offers a comprehensive solution to many of the existing mysteries in the field. By proposing that the vacuum is a dielectric medium and quantum particles are quantized excitation waves of the vacuum, the book provides a clear physical interpretation of wave-particle duality and explains the physical basis of energy, momentum, and mass.

In recent decades, twistor theory has grown into an irreplaceable tool for the study of scattering amplitudes in gauge theory and gravity. This book introduces the reader to cutting-edge advances in twistor theory and its applications to general relativity. The problem of graviton scattering in four dimensions is shown to be dual to dramatically simpler computations in a two-dimensional CFT known as a twistor sigma model. Twistor sigma models are the first step toward a holographic description of gravity in asymptotically flat space-times. They underpin the infinitely many asymptotic symmetries of flat space physics discovered in celestial holography, and extend them to exciting new arenas like curved space-times. They also yield intrinsically mathematical results in the field of hyperkähler manifolds. This volume will be of broad interest to students and researchers looking for an accessible entry point into twistor geometry, scattering amplitudes, and celestial holography. It will also provide an invaluable reference for specialists by bringing together results from a host of different disciplines.

The Springer Handbook of Spacetime is dedicated to the ground-breaking paradigm shifts embodied in the two relativity theories, and describes in detail the profound reshaping of physical sciences they ushered in. It includes in a single volume chapters on foundations, on the underlying mathematics, on physical and astrophysical implications, experimental evidence and cosmological predictions, as well as chapters on efforts to unify general relativity and quantum physics. The Handbook can be used as a desk reference by researchers in a wide variety of fields, not only by specialists in relativity but also by researchers in related areas that either grew out of, or are deeply influenced by, the two relativity theories: cosmology, astronomy and astrophysics, high energy physics, quantum field theory, mathematics, and philosophy of science. It should also serve as a valuable resource for graduate students and young researchers entering these areas, and for instructors who teach courses on these subjects.

One of the main unanswered question of modern Physics is "How does gravity behave at small scales?". The aim of this thesis is to illustrate in a comprehensive but accessible way how to look for deviations from Einstein's theory of General Relativity in this regime, looking at the simplest celestial bodies: static and spherically symmetric ones.

Classical mechanics is the basis for any university-level study of technical-scientific disciplines. But most existing manuals use a technological and engineering approach, with basic aspects sometimes insufficiently highlighted. This book introduces the concepts and applications of classical mechanics into Newtonian formalism. Newtonian dynamics is useful for solving applied physics and engineering problems, but also a fascinating theory anchored in questions posed since the times of the Greek philosophers, regarding space, the flow of time, measurable physical quantities, the physical principles with the mathematical structure needed to describe the Universe, etc. The author aims to encourage students to think about these fundamental aspects and how they will be addressed in modern physics, including the successes and limitations of Newton's mechanics. The book is designed to mirror the progress of the students using it, with earlier chapters assuming no more than basic high school instruction and later ones geared toward subsequent enhanced understanding. The book is designed for students of undergraduate programs in physics, mathematics, chemistry, and engineering who will deal with modern physics, as they will benefit from an approach in which the aspects of classical mechanics are introduced in a propaedeutic approach towards relativistic physics and quantum mechanics.

This book reviews various modified gravity models, including those with modifications in the pure gravitational sector; those involving extra fields, that is, scalar-tensor and vector-tensor gravity theories; gravity models with Lorentz symmetry breaking; and nonlocal gravity models. The authors discuss both classical and quantum aspects of these theories. The book is unique in bringing together all the current alternatives to Einstein gravity in one source and serves as an excellent starting point for graduate students and other newcomers seeking an overview.

This book summarizes the basics of electricity and magnetism prior to covariant formulation of Maxwell's equations. The book works out the basics of special relativity and then applies the covariant formalism to understand radiation, both in vacuum and in material medium. The emphasis is on cleaner mathematical formalism based on experimental facts. The book contains many problems/exercises which will help the students to understand the basics of the subject.

Découverts il y a plus de 30 ans, les quasars et les radiogalaxies sont des galaxies particulières qui manifestent en leur centre une activité intense.

This thesis is devoted to the systematic study of non-local theories that respect Lorentz invariance and are devoid of new, unphysical degrees of freedom. Such theories are attractive for phenomenological applications since they are mostly unconstrained by current experiments. Non-locality has played an increasingly important role in the physics of the last decades, appearing in effective actions in quantum field theory, and arising naturally in string theory and non-commutative geometry.

The ancient Greeks believed that everything in the Universe should be describable in terms of geometry. This thesis takes several steps towards realising this goal by introducing geometric descriptions of systems such as quantum gravity, fermionic particles and the origins of the Universe itself.

This book seeks to present a new way of thinking about the interaction of gravitational fields with quantum systems. Despite the massive amounts of research and experimentation, the myriad meetings, seminars and conferences, all of the articles, treatises and books, and the seemingly endless theorization, quantization and just plain speculation that have been engaged in regarding our evolving understanding of the quantum world, that world remains an enigma, even to the experts.