This book gives a comprehensive account of modern x-ray science based on the use of synchrotron radiation and x-ray-free electron lasers (XFELs), presented against the historical background of the puzzling nature of light, and culminating in quantum electrodynamics (QED) and quantum optics. It covers the physical foundations of the creation, properties, and detection of x-rays, uniquely emphasizing how the classical wave theory emerges from the photon concept of QED in lowest order. It then presents the formulation of the interactions of x-rays with atomic matter from both semi-empirical classical and first-principles quantum points of view. Particular attention is given to the evolution from optical to x-ray interactions, with emphasis on the unique power of x-rays in providing atom and chemical-bond specific information and their ability to separate charge and spin phenomena through x-ray polarization (dichroism) effects. In addition to various x-ray spectroscopy techniques, the book also discusses x-ray imaging and diffractive imaging, which through XFELs is now extended to the intrinsic length scale of atoms and chemical bonds and the associated timescales of their motions and transformations.weiterlesen