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Flat paper stained with water buckles and wrinkles as it swells and deforms out of the original plane. Here we quantify the geometry and mechanics of a strip of paper that swells when it imbibes water from a narrow capillary. Characterizing the hygroexpansive nature of paper shows that thickness-wise swelling is much faster than in-plane water imbibition, leading to a simple picture for the process by which the strip of paper bends out of the plane. We model the out-of-plane deformation using a quasi-static theory and show that our results are consistent with quantitative experiments.

This book describes the key role played by thermally excited defects such as vortices, disclinations, dislocations, vacancies and interstitials in the physics of crystals, superfluids, superconductors, liquid crystals and polymer arrays. Geometrical aspects of statistical mechanics become particularly important when thermal fluctuations entangle or crumple extended line-like or surface-like objects in three dimensions. In the case of entangled vortices above the first-order flux lattice melting transition in hightemperature superconductors, the lines themselves are defects. A variety of theories combined with renormalization-group ideas are used to describe the delicate interplay among defects, statistical mechanics and geometry characteristic of these problems in condensed matter physics. This indispensible guide has its origins in Professor Nelson’s contributions to summer schools, conference proceedings and workshops over the past twenty years. It provides a coherent and pedagogic graduate-level introduction to the field of defects and geometry.

1. The dynamical equations 2. Water waves 3. Viscosity 4. Vortices 5. Instability 6. Turbulence 7. Drag and lift

The 57th annual meeting of the APS Division of Plasma Physics (DPP) was held November 16–20, 2015 in Savannah, Georgia. The meeting brings together researchers (undergraduate students through retirees) from all areas of plasma physics. 1887 abstracts were included in the program, approximately 200 more than the previous year. The presentations included five invited review talks, 97 invited talks, three invited postdeadline talks, and four tutorials. Furthermore, there were approximately 1780 contributed presentations, with about 40% oral and 60% poster. Three mini-conferences were held concurrently.

New stability criteria, for steady nonparallel solutions of the shallow‐water equations, are shown to be incorrect through the use of a counterexample: the sine profile in an f‐plane channel. If the channel is wide enough and the Coriolis parameter does not vanish, the conditions in question predict stability but the flow is found to be unstable to quasigeostrophic normal modes.

You’d have to be living in a cave in Afghanistan not to know that cosmology is in the midst of an extraordinary period of discovery—perhaps even a golden age. But you might not know that it all started on April Fool’s Day 60 years ago. Ralph Alpher, Hans Bethe, and George Gamow published a Letter to the Editor entitled “The Origin of the Chemical Elements” in the April 1 issue of Physical Review. Gamow asked Bethe to add his name to the paper he and his student Alpher were writing to create the author list “alpha, beta, gamma”; Bethe agreed. The αβγ paper marked the birth of the hot Big Bang cosmology and started the march to precision cosmology. It is also exhibit 1 in my case that an interestingly wrong paper can be far more important than a trivially right paper; recall Wolfgang Pauli’s famous putdown, “It isn’t even wrong.” In 1948 cosmology was practiced by a handful of hardy individuals, mostly astronomers; determinations of the Hubble constant were almost 10 times as large as they are today; the redshifts of less than a hundred relatively nearby galaxies had been measured; and the 200-inch Hale telescope on Mount Palomar was a year away from first light. Cosmology is now center-stage science and attracts a thousand researchers, both physicists and astronomers; two Nobel Prizes have been awarded (1978 and 2006, and more to come); an armada of telescopes, experiments, and even accelerators has been brought to bear on the problems of the universe; and precision cosmology is no longer an oxymoron.

Feynman diagrams have revolutionized nearly every aspect of theoretical physics since the middle of the twentieth century. Introduced by the American physicist Richard Feynman (1918-88) soon after World War II as a means of simplifying lengthy calculations in quantum electrodynamics, they soon gained adherents in many branches of the discipline. Yet as new physicists adopted the tiny line drawings, they also adapted the diagrams and introduced their own interpretations. Drawing Theories Apart traces how generations of young theorists learned to frame their research in terms of the diagrams - and how both the diagrams and their users were molded in the process. Drawing on rich archival materials, interviews, and more than five hundred scientific articles from the period, Drawing Theories Apart uses the Feynman diagrams as a means to explore the development of American postwar physics. By focusing on the ways young physicists learned new calculational skills, David Kaiser frames his story around the crafting and stabilizing of the basic tools in the physicist's kit - thus offering the first book to follow the diagrams once they left Feynman's hands and entered the physics vernacular.

Introduction and Review of Quantum Mechanics. Bonding in Molecules and Solids. Band Structure of Solids. Quantum Mechanics Interlude. Band Structure and Defects in Bulk Semiconductors. Physics and Applications of Low-Dimensional Structures. Diamagnetism and Paramagnetism. Ferromagnetism and Magnetic Order. Superconductors. First Principles Calculation of Electronic Properties. Appendix A: The Variational Method with an Arbitrary Parameter - the Hydrogen Atom. Appendix B: The Hydrogen Atom and the Periodic Table.

Since an atomic Bose-Einstein condensate, predicted by Einstein in 1925, was first produced in the laboratory in 1995, the study of ultracold Bose and Fermi gases has become one of the most active areas in contemporary physics. This book explains phenomena in ultracold gases from basic principles, without assuming a detailed knowledge of atomic, condensed matter, and nuclear physics. This new edition has been revised and updated, and includes new chapters on optical lattices, low dimensions, and strongly-interacting Fermi systems. This book provides a unified introduction to the physics of ultracold atomic Bose and Fermi gases for advanced undergraduate and graduate students, as well as experimentalists and theorists. Chapters cover the statistical physics of trapped gases, atomic properties, cooling and trapping atoms, interatomic interactions, structure of trapped condensates, collective modes, rotating condensates, superfluidity, interference phenomena, and trapped Fermi gases. Problems are included at the end of each chapter.

Photocount distributions for a narrow-band laser receiver in thermal background radiation are developed in a parallel sense to the envelope density functions for radio frequency radar. While classical detection performance is dependent on the received signal-to-noise, the results show that narrow-band photocount detection additionally depends on the absolute levels of the received signal and noise.

In Phys. Fluids 19, 118105 (2007), I. Lunati disputes my earlier paper [Phys. Fluids 18, 047102 (2006)], in which I pointed out an anomaly arising from Thomas Young’s concept of solid/fluid surface tension. The present article examines Lunati’s reasoning and concludes that my earlier paper is correct.