Issues
Physics Update
Letters
‘Radiation Risk and Ethics’: Health Hazards, Prevention Costs, and Radiophobia
Search and Discovery
Explorers Focus More Sharply on Their Prey: Weakly Interacting Dark Matter
Results are starting to come in from detectors honed to hunt for the universe's missing mass. Although not conclusive, the reports are a harbinger of what's to come.
Ultracold Neutrons are Magnetically Trapped at NIST
Despite its ubiquity, the neutron still resists precise measurement of its lifetime. More precision would allow tests of Big Bang nucleosynthesis and theories beyond the Standard Model.
Magnetic Semiconductors Enable Efficient Electrical Spin Injection
Semiconductors doped with manganese may provide the answer to a long‐standing question in magneto‐electronics.
Articles
Radionuclide Therapy
Physicists and physicians are working together to devise new methods for exploiting the power of ionizing radiation to treat cancer and coronary artery disease.
A Fresh Look at Entropy and the Second Law of Thermodynamics
The existence of entropy, and its increase, can be understood without reference to either statistical mechanics or heat engines.
The Composite Fermion: A Quantum Particle and Its Quantum Fluids
The fractional quantum‐Hall effect and other exotic behaviors of electrons trapped in two dimensions can be understood in terms of composite particles—electrons sporting attached flux quanta.
