Showing papers in "Physics Today in 2001"
TL;DR: In this paper, 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 is provided.
Abstract: 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.
3,017 citations
664 citations
TL;DR: In this article, the authors present new fabrication challenges and finding new applications in biology, chemistry, and materials science for handling nanoliter quantities of fluids, which is a new fabrication challenge.
Abstract: Devices for handling nanoliter quantities of fluids are creating new fabrication challenges and finding new applications in biology, chemistry, and materials science.
646 citations
590 citations
TL;DR: In this article, half metals belong to a new class of materials that look set to play a key role in next-generation electronic devices, and half metals are used for the first time.
Abstract: Not to be confused with semiconductors, half metals belong to a new class of materials that look set to play a key role in next-generation electronic devices.
533 citations
TL;DR: For example, this article showed that seismic waves, geodetic measurements, and numerical experiments can be used to predict the interior rupture of the Earth's interior, without directly observing it.
Abstract: Seismologists have never directly observed rupture in Earth’s interior. Instead, they glean information from seismic waves, geodetic measurements, and numerical experiments.
442 citations
TL;DR: Geometrical structures and scaling behavior provide insights into the nature of convective turbulence and some risky generalizations about complex systems as discussed by the authors, and they can be used to predict the scaling behavior of complex systems.
Abstract: Geometrical structures and scaling behavior provide insights into the nature of convective turbulence and some risky generalizations about “complex systems.”
376 citations
TL;DR: In this paper, the authors present a survey of statistical physics and lattices, including phase transition renormalization, duality, and planar planar model and Coulomb system XY model.
Abstract: Fundamentals of statistical physics: the lectures - a survey one particle and many Gaussian distributions quantum mechanics and lattices. Random dynamics: diffusion and hopping from hops to statistical mechanics correlations and response. More statistical mechanics: statistical thermodynamics Fermi, Bose, and other. Phase transitions: overview of phase transitions mean field theory of critical behaviour continuous phase transitions renormalization in one dimension real space renormalization techniques duality planar model and Coulomb systems XY model, renormalization and duality.
356 citations
TL;DR: In this article, the representation theory of finite groups is presented in terms of modules, with considerable emphasis placed on constructing characters, and applications covered include the use of character theory in studying subgroup structure and permutation groups, and how to use representation theory to investigate molecular vibration.
Abstract: This book provides a modern introduction to the representation theory of finite groups. Now in its second edition, the authors have revised the text and added much new material. The theory is developed in terms of modules, since this is appropriate for more advanced work, but considerable emphasis is placed upon constructing characters. Included here are the character tables of all groups of order less than 32, and all simple groups of order less than 1000. Applications covered include Burnside's paqb theorem, the use of character theory in studying subgroup structure and permutation groups, and how to use representation theory to investigate molecular vibration. Each chapter features a variety of exercises, with full solutions provided at the end of the book. This will be ideal as a course text in representation theory, and in view of the applications, will be of interest to chemists and physicists as well as mathematicians.
346 citations
TL;DR: In time, solid-state devices should provide inexpensive, environmentally friendly illumination that changes the way we think about using artificial light as discussed by the authors, which is the goal of solid state devices.
Abstract: In time, solid-state devices should provide inexpensive, environmentally friendly illumination that changes the way we think about using artificial light.
346 citations
TL;DR: In this article, the superconductivity of high-Tc cuprates is compared to the superfluidity of helium-3, and it is shown that this metal oxide resembles the high-C cuprates.
Abstract: Structurally, this metal oxide resembles the high-Tc cuprates, but its superconductivity is more like the superfluidity of helium-3.
TL;DR: In this paper, the authors describe Nanometer-scale islands that form spontaneously on a semiconductor substrate have atomlike properties and potential applications in optical and optoelectronic devices, quantum computing, and information storage.
Abstract: Nanometer-scale islands that form spontaneously on a semiconductor substrate have atomlike properties and potential applications in optical and optoelectronic devices, quantum computing, and information storage.
TL;DR: The unique environment in liquid helium droplets opens up new opportunities for molecular spectroscopy and for probing superfluid phenomena on the atomic scale as mentioned in this paper, and it has been used extensively in the literature.
Abstract: The unique environment in liquid helium droplets opens up new opportunities for molecular spectroscopy and for probing superfluid phenomena on the atomic scale.
TL;DR: The Road since Structure as mentioned in this paper is a collection of essays extending and rethinking the perspectives of Structure as well as an extensive and remarkable autobiographical interview in which Kuhn discusses the course of his life and philosophy.
Abstract: Thomas Kuhn will undoubtedly be remembered primarily for The Structure of Scientific Revolutions, a book that introduced one of the most influential conceptions of scientific progress to emerge during the twentieth century. The Road since Structure, assembled with Kuhn's input before his death in 1996, follows the development of his thought through the later years of his life: collected here are several essays extending and rethinking the perspectives of Structure as well as an extensive and remarkable autobiographical interview in which Kuhn discusses the course of his life and philosophy.
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TL;DR: In this article, a propagation-based alternative to interferometry is proposed to provide increased opportunities for phase measurements using x rays, electrons, neutrons, and other waves, and the phase measurement permeates modern science.
Abstract: Phase measurement permeates modern science. New propagation-based alternatives to interferometry are providing increased opportunities for phase measurements using x rays, electrons, neutrons, and other waves.
TL;DR: By monitoring the response of individual protein and DNA molecules to pulling and twisting, biophysicists can learn much about their structure and their interactions.
Abstract: By monitoring the response of individual protein and DNA molecules to pulling and twisting, biophysicists can learn much about their structure and their interactions.
TL;DR: In this article, thin magnetic films are layered to make complex structures with unique magnetic properties, and these structures are revolutionizing electronic data storage, leading to the development of new devices based on these structures.
Abstract: Once studied primarily for their effects on light, thin magnetic films are today being layered to make complex structures with unique magnetic properties. Devices based on these structures are revolutionizing electronic data storage.
TL;DR: In this article, Mesoscopic physics helps explain how scattering can increase the information transfer rate for cell phones and other wireless microwave communication devices, rather than decreasing the efficiency of wireless communication.
Abstract: Rather than decreasing efficiency, scattering can actually increase the information transfer rate for cell phones and other wireless microwave communication devices. Mesoscopic physics helps explain how.
TL;DR: The field of gaseous electronics underlies the understanding of a lightning-like phenomenon of spectacular extent, shape, and color as discussed by the authors, and is the main source of inspiration for our work.
Abstract: The venerable field of gaseous electronics underlies the understanding of a lightning-like phenomenon of spectacular extent, shape, and color.
TL;DR: In this paper, the authors describe the use of microelectromechanical systems in a variety of applications, including triggering airbags and measuring the Casimir force, and they may revolutionize the way we think about machines.
Abstract: Microelectromechanical systems are currently used in a variety of applications, including triggering airbags and measuring the Casimir force. In the future, they may revolutionize the way we think about machines.
TL;DR: The story of Boltzmann's atom is described in this paper, where Lindley combines expert storytelling with his deep understanding of the subject to shed light on an enthalling period of ferment and discovery.
Abstract: In the tradition of LONGITUDE, BOLTZMANN'S ATOM is the dramatic true story of the fascinating characters behind the greatest turning point in modern science. In 1900 the existence of the atom was a matter of great scientific debate, but by 1905, the atom was an accepted fact and the work of Albert Einstein, Max Planck and Marie Curie launched the atomic century. At the centre of this dramatic story, told against the backdrop of turn-of-the-century Vienna, is Ludwig Boltzmann, the forgotten genius who set the atomic revolution in motion. Boltzmann, an Austrian physicist, was an unabashed believer in the atomic hypothesis. The most visionary physicist of his age, he explained how the properties of matter arise from the movement of their smallest parts. But during his lifetime, Boltzmann's enthusiasm and progress were constantly thwarted by his nemesis, Ernst Mach. Mach, a respected scientist, didn't see the point of explaining what could not be seen. He developed a philosophy to bolster his conviction that science ought to stick to what it can measure directly and ensnared Boltzmann in an all-consuming philosophical debate on the subject. Though he had almost single-handedly invented twentieth-century theoretical physics, Boltzmann died a broken man, unaware that his vision would eventually lead to the greatest chain of scientific dscoveries ever made. In BOLTZMANN'S ATOM David Lindley combines expert storytelling with his deep understanding of the subject to shed light on an enthalling period of ferment and discovery.
TL;DR: The latest clocks use a single ion to measure time with an anticipated precision of one part in 1018 as mentioned in this paper, which is the same as the clock used in the present clock.
Abstract: The latest clocks use a single ion to measure time with an anticipated precision of one part in 1018.
TL;DR: Grain boundaries in high-temperature superconductors illustrate the interplay of physics, materials science, and applications in complex materials as mentioned in this paper, and illustrate the relationship between physics and materials science.
Abstract: Grain boundaries in high-temperature superconductors illustrate the interplay of physics, materials science, and applications in complex materials.
TL;DR: In this article, the authors introduce the concept of quantum wave theory and its application to molecular physics. But they do not discuss the application of quantum theory to point groups. And they only focus on the properties of the quantum wave.
Abstract: 1. Introduction and Background to Quantum Mechanics. Aim of Theoretical Chemistry. Key Concepts from Classical Physics. Classical Mechanics. Classical Wave Theory. Early History of Quantum Mechanics. Particle Nature of Light. Wave Nature of Particles. Uncertainty Principle. Discovery of Quantum Mechanics. Concepts in Quantum Mechanics. 2. Quantum Theory. Postulates of Quantum Mechanics. Definitions of ...Y and ...|Y|2. Operators. Time-Dependent and Time-Independent Schroedinger Equations. Eigenvalues. Expectation Values. Properties of the Time-Independent Schroedinger Eigenfunctions. 3. Particle-in-Box Models. Particle in a One-Dimensional Box. Particle in a Two-Dimensional Box. Particle in a Three-Dimensional Box. Free-Electron Molecular Orbital Model. 4. Rigid-Rotor Models and Angular Momentum Eigenstates. Motions of a Diatomic Molecule: Separation of the Center of Mass. Rigid-Rotor Model in Two Dimensions. Three-Dimensional Rigid Rotor. Spherical Harmonics. Rotational Spectra. Angular Momentum. Dirac Notation. Raising and Lowering Angular-Momentum Operators. 5. Molecular Vibrations and Time-Independent Perturbation Theory. Diatomic Molecule Vibrations. Raising and Lowering Operators for the Harmonic Oscillator. Polyatomic Molecule Vibrations. Time-Independent Perturbation Theory. Examples. 6. The Hydrogen Atom. The Schroedinger Equation. Radial Solutions and Eigenvalues. Energy Eigenvalues Spectroscopy of the H Atom. Properties of Hydrogen and Hydrogenlike Wavefunctions. Atomic Units. 7. The Helium Atom. Schroedinger Equation. Independent-Particle Model. The Variational Method. Better Wavefunctions. 8. Electron Spin and the Pauli Principle. Electron Spin. The Pauli Principle. He-Atom Wavefunctions, Including Spin. Excited State of He. Energies of He(1 s2s) States. Interaction of Electron Spin with Magnetic Fields. EPR and NMR. 9. Many-Electron Atoms. Many-Electron Hamiltonian and Schroedinger Equation. Slater Determinants. Hartree Method. Hartree-Fock Method. Koopmans' Theorem. Electron Correlation. Constants of the Motion. Angular-Momentum Operators for Many-Electron Atoms. Relativistic Effects. 10. Homonuclear Diatomic Molecules. Hydrogen Molecular Ion: Born-Oppenheimer Approximation. LCAO-MO Treatment of H 2 +. Other H 2 + States. Electronic Structure of Homonuclear Diatomics. Electronic Structure of H 2: Molecular Orbital and Valence Bond Wavefunctions. Improvements to MO and VB Results for H 2. 11. Ab Initio and Density Functional Methods. LCAO-MO-SCF Theory for Molecules. Atomic Orbitals. Hartree-Fock Calculations. Beyond Hartree-Fock. Density Functional Theory Methods. 12. Semiempirical Methods. Huckel Model. Extended Huckel Method. PPP Method. NDO Methods. 13. Applications of Group Theory. Group Theory for Point Groups. Applications of Group Theory to Molecular Quantum Mechanics. Symmetry Properties of Many-Electron Wavefunctions. Symmetry Properties of Molecular Vibrations. 14. Applications of Electronic Structure Theory. Potential-Energy Functions. Optimized Geometries and Frequencies. IR Spectra. Barriers to Reaction. Excited States. Molecular Clusters. Remarks on Other Methods. 15. Time Dependence and Spectroscopy. Transition Probabilities and the Golden Rule. Electronic Spectroscopy of Molecules. Vibration (Infrared) Spectroscopy. Appendices. Mathematical Background. Two-Electron Repulsion Integral. Character Tables. Atomic Units, Energy Conversion Factors, and Physical Constants. Solutions to Odd-Numbered Problems. Index.
TL;DR: In this paper, the authors argue that today's science education, which teaches all students to do science and think like scientists, has depended on the involvement of scientists and their societies.
Abstract: Today’s science education, which teaches all students to do science and think like scientists, has depended on the involvement of scientists and their societies. It must continue to do so.
TL;DR: In this article, the authors used synchrotron radiation with photon energies at or below 1 keV to give new insights into such areas as wet cell biology, condensed matter physics and extreme ultraviolet optics technology.
Abstract: Synchrotron radiation with photon energies at or below 1 keV is giving new insights into such areas as wet cell biology, condensed matter physics and extreme ultraviolet optics technology.