Physics

Until the 1970s, all materials studied consisted of periodic arrays of unit cells, or were amorphous. In the last decades a new class of solid state matter, called aperiodic crystals, has been found. It is a long range ordered structure, but without lattice periodicity. It is found in a wide range of materials: organic and anorganic compounds, minerals (including a substantial portion of the earths crust), and metallic alloys, under various pressures and temperatures. Because of the lack of periodicity, the usual techniques for the study of structure and physical properties no longer work, and new techniques have to be developed. This book deals with the characterization of the structure, the structure determination, and the study of the physical properties, especially dynamical and electronic properties of aperiodic crystals. The treatment is based on a description in a space with more dimensions than three, the so-called superspace. This allows us to generalise the standard crystallography and to look differently at the dynamics. The three main classes of aperiodic crystals, modulated phases, incommensurate composites, and quasicrystals are treated from a unified point of view, which stresses the similarities of the various systems.

This book covers the theory, practicalities, and the extensive applications of neutron powder diffraction in materials science, physics, chemistry, mineralogy, and engineering. Various highlight applications of neutron powder diffraction are outlined in the introduction, then the theory is developed and instrumentation described sufficient for a return to the applications. The book covers the use of neutron powder diffraction in the solution (hard) and refinement (more straightforward) of crystal and magnetic structures, applications of powder diffraction in quantitative phase analysis, extraction of microstructural information from powder diffraction patterns, and the applications of neutron diffraction in studies of elastic properties and for the measurement of residual stress. Additional theory to underpin these various applications is developed as required.

Progress in modern radio astronomy led to the discovery of space masers in the microwave range, and it became a powerful tool for studies of interstellar star-forming molecular clouds. Progress in observational astronomy, particularly with ground-based huge telescopes and the space-based Hubble Space Telescope, has led to recent discoveries of space lasers in the optical range. These operate in gas condensations in the vicinity of the mysterious star Eta Carinae (one of the most luminous and massive stars of our Galaxy). Both maser and laser effects, first demonstrated under laboratory conditions, have now been discovered to occur under natural conditions in space too. This book describes consistently the elements of laser science, astrophysical plasmas, modern astronomical observation techniques, and the fundamentals and properties of astrophysical lasers.

This book gives an account of the progress that has been made in the fields of atomic physics and laser spectroscopy during the last fifty years. The first five chapters prepare the foundations of atomic physics, classical electro-magnetism, and quantum mechanics, which are necessary for an understanding of the interaction of electromagnetic radiation with free atoms. The application of these concepts to processes involving the spontaneous emission of radiation is then developed in Chapters 6, 7, and 8, while stimulated emission and the properties of gas and tunable dye lasers form the subject matter of Chapters 9 to 14. The last four chapters are concerned with the physics and applications of atomic resonance fluorescence, optical double-resonance, optical pumping, and atomic beam magnetic resonance.

Atomic force microscopy (AFM) is an amazing technique that allies a versatile methodology (it allows the imaging of samples in liquid, vacuum or air) to imaging with unprecedented resolution. But it goes one step further than conventional microscopic techniques; it also allows us to make measurements of magnetic, electrical or mechanical properties of the widest possible range of samples, with nanometre resolution. This book will demystify AFM for the reader, making it easy to understand, and easy to use. Peter Eaton and Paul West share a common passion for atomic force microscopy. However, they have very different perspectives on the technique. Over the past 12 years Peter used AFMs as the focal point of his research in a variety of scientific projects from materials science to biology. Paul, on the other hand, is an instrument builder and has spent the past 25 years creating these microscopes for scientists and engineers. This insightful book covers the theory, practice and applications of atomic force microscopes and will serve as an introduction to AFM for scientists and engineers that want to learn about this powerful technique, and as a reference book for expert AFM users. Application examples from the physical, materials, and life sciences, nanotechnology and industry illustrate the many and varied capabilities of the technique.

Brownian motion is the incessant motion of small particles immersed in an ambient medium. It is due to fluctuations in the motion of the medium particles on the molecular scale. The name has been carried over to other fluctuation phenomena. This book treats the physical theory of Brownian motion. The extensive mathematical theory, which treats the subject as a subfield of the general theory of random processes, is touched on but not presented in any detail. Random or stochastic process theory and statistical mechanics are the primary tools. The first eight chapters treat the stochastic theory and some applications. The next six present the statistical mechanical point of view. Then follows chapters on applications to diffusion, noise, and polymers, followed by a treatment of the motion of interacting Brownian particles. The book ends with a final chapter treating simulation, fractals, and chaos.

This book introduces the full range of activity in the rapidly growing field of nonlinear dynamics. Using a step-by-step introduction to dynamics and geometry in state space as the central focus of understanding nonlinear dynamics, this book includes a thorough treatment of both differential equation models and iterated map models (including a detailed derivation of the famous Feigenbaum numbers). It includes the increasingly important field of pattern formation and a survey of the controversial question of quantum chaos. Important tools such as Lyapunov exponents, fractal dimensions, and correlation dimensions are treated in detail. Several appendices provide a detailed derivation of the Lorenz model from the Navier-Stokes equation, a summary of bifurcation theory, and some simple computer programs to study nonlinear dynamics. Each chapter includes an extensive, annotated bibliography.

The bond valence model, which is derived from the ionic model, is expressed through a number of rules and equations that determines which acid-base bond structures can exist. Chief among these rules is the bond valence sum rule, which states that the sum of bond valences around an ion is equal to its atomic valence. These rules can be used to understand many of the properties of inorganic structures, such as bond lengths, coordination numbers, their structures and their solution chemistry. The unusual geometries and properties of hydrogen bonds follow naturally from these rules. Because the model describes chemically ideal structures, it allows one to quantify the role of electronic anisotropies and steric strain in observed structures, the latter frequently leading to phase transitions in crystals. In favourable cases the model can be used for structure prediction by constructing the bond network ab initio and then mapping this onto a compatible space group. The model has applications in many fields ranging from earth sciences to biology.

In recent years, the old idea that gauge theories and string theories are equivalent has been implemented and developed in various ways, and there are by now various models where the string theory/gauge theory correspondence is at work. One of the most important examples of this correspondence relates Chern-Simons theory, a topological gauge theory in three dimensions which describes knot and three-manifold invariants, to topological string theory, which is deeply related to Gromov-Witten invariants. This has led to some surprising relations between three-manifold geometry and enumerative geometry. This book gives the first presentation of this and other related topics. After an introduction to matrix models and Chern-Simons theory, the book describes in detail the topological string theories that correspond to these gauge theories and develops the mathematical implications of this duality for the enumerative geometry of Calabi-Yau manifolds and knot theory.

This book records the long scientific search for extraterrestrial intelligence (SETI). Although philosophical speculation about alien civilizations dates to antiquity, the invention of the telescope in the 17th century inspired scientists like Johannes Kepler, Galileo Galilei, René Descartes, and Christiaan Huygens to consider the possibility of intelligent creatures living on the Moon or on the planets of our solar system. By the late 19th century, Mars became the focus of attention for astronomers searching for civilized life near the earth. The belief that Mars contained a superior civilization capable of building a global system of irrigation canals on the planet was supported by the Italian astronomer Giovanni Schiaparelli and the American Percival Lowell. In the 1960s and 1970s, data gathered by Soviet and American spacecraft challenged the assumption that Mars was the habitat for life of any sort. As the hunt for alien civilizations in the solar system waned, a new search began for signs of intelligent life in remote parts of the universe. This search used radio telescopes to scan the skies for any messages transmitted to earth by advanced extraterrestrial civilizations. Distinguished modern astronomers and physicists — Frank Drake, Philip Morrison, Carl Sagan — were convinced that electronic technology would allow contact with civilizations located many light years from earth. Unfortunately, the search for extraterrestrial intelligence was compromised by anthropomorphism (attributing human qualities to alien life and culture) and by an unconscious religious outlook that the superior beings living in outer space would help solve pressing social, economic, and technological problems.