Issues
Physics Update
Reference Frame
Letters
Mass Matters: The Rest Mass Issue, QCD, and the Pursuit of Dreams
Search and Discovery
Learning about High‐ Superconductors from Their Imperfections
Researchers in Berkeley and Tokyo have demonstrated the great potential of a scanning tunneling microscope for studying the behavior of superconductors on an atomic scale.
Experiments Reveal How Heat Is Mixed into Cold Dense Water in the Abyssal Ocean
By tracing the diffusion of a dye, researchers have found suggestive evidence that the moon promotes the flow of heat in the deep ocean.
A Photon‐Activated Switch Detects Single Far‐Infrared Photons
The absorption of a single photon can turn the current through a quantum dot on or off.
Survey Halves Estimated Population of Big Near‐Earth Asteroids
NASA's goal is to determine, as soon as possible, the orbits of all asteroids near enough and big enough to threaten cataclysmic damage.
Articles
Nonequilibrium Patterns in Granular Mixing and Segregation
Granular flows that mix different species exhibit a surprisingly diverse repertoire of striking and beautiful behaviors. Better understanding of the mixing process should help in predicting whether a given flow will mix—or segregate—its constituents.
Atmospheric Infrasound
The search for ways to monitor compliance with the Comprehensive Test Ban Treaty has sparked renewed interest in sounds with frequencies too low for humans to hear.
Liquid Crystals and Carbon Materials
The macroscopic properties of carbon materials are determined by their structure at the nanometer length scale, and there is great potential to tailor their structure during the liquid‐crystal phase of the synthesizing process.