June 1999 Contents

ARTICLES

Battling Decoherence: The Fault-Tolerant Quantum Computer

Quantum computers have the potential to do certain calculations faster than any foreseeable classical computers, but their success will depend on preserving complex coherent quantum states. Recent discoveries have shown us how to do that — John Preskill

Electron Spin and Optical Coherence in Semiconductors

Using ultrafast laser pulses and magnetic fields, electron-hole pairs in semiconductors may be carefully manipulated, and electron spin states can be preserved over surprisingly long times and distances — David D. Awschalom and James M. Kikkawa

Revisiting the Black Hole

A resurgence of theoretical and observational interest in black holes has given new impetus to the study of these intriguing objects — Roger Blandford and Neil Gehrels

DEPARTMENTS

Search and Discovery

• New data from Mars hint at a dynamic past

• Traveling-wave thermoacoustic heat engines attain high efficiency

• Adiabatic quantum electron pump produces DC current

• Experiments at Jefferson lab and MIT probe for strange quarks in the proton

Washington Reports

• Specter of SSC haunts Spallation Neutron Source as recently appointed project director takes charge

• Washington Briefings: Toward a permanent R&D tax credit; Scientific advice to the world; Chernobyl's fallout revisited; Roles and rules in the government-university partnership

Physics Community

• Graduate physics in Wyoming hinges on boosting undergrad enrollment and funding observatory

• Professional master's degrees promise quicker entry into industry jobs

• APS time line celebrates a century of physics

• Duke laser lab gets new director
  A physicist writes mysteries about a physicist who solves mysteries

• Tenure is as tenure does

• Web Watch

Books

Annals of the Former World, J. McPhee (reviewed by W. G. Ernst)

String Theory, J. Polchinski (reviewed by J. A. Harvey)

Accretion Processes in Star Formation, L. Hartmann (reviewed by J. Stone)

Physics in the 20th Century, C. Suplee (reviewed by R. H. March)

Reasoning with the Infinite: From the Closed World to the Mathematical Universe, M. Blay (reviewed by D. B. Meli)

Introduction to Bioanalytical Sensors, A. J. Cunningham (reviewed by R. H. Austin)

Plus ...

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