June 1998 Contents

Articles:

Polymer Rheology

Neither purely viscous nor perfectly elastic, polymeric fluids have a fading memory of their undeformed shape and display spectacular phenomena not seen in Newtonian fluids -- Daniel De Kee and Kurt F. Wissbrun

The Magic of Helium-3 in Two, or Nearly Two, Dimensions

Despite being among the most studied physical systems, low-temperature mixtures of helium-3 and helium-4 continue to exhibit phenomena that fascinate and surprise -- Robert B. Hallock

The Hipparcos Astrometry Mission

The first orbiting observatory dedicated to high-precision parallax measurement has completed its task. We now have direct distance determinations with accuracies better than 10% to more than 20 000 stars -- Michael Perryman

Departments:

Reference Frame

Nibbling the bullet -- Daniel Kleppner

Search and Discovery

Very distant supernovae suggest that the cosmic expansion is speeding up. Two rival groups of observers have concluded that the gravitational slowing of the Hubble expansion is being opposed by a repulsive cosmological constant, or something even more exotic.

Are stripes a universal feature of high-T_c superconductors? Do the spins and charges associated with copper and oxygen atoms in high-temperature superconductors arrange themselves in orderly rows in the copper oxide plane? Recent studies suggest that not just one but several families of the cuprates may feature such stripes, although in most cases the stripes are not static but fluctuate with time and position.

Materials of a different stripe.

Washington Reports

In retirement, Jack Gibbons returns to his roots---a gentleman farmer and science policy exponent

At White House, Stephen Hawking enthralls Clintons and guests with cyber-lecture on physics

Washington dispatches: Enlarging the nuclear club; Safeguarding old Soviet nukes

Washington ins & outs: Science board election; New faces at DOD, NSF, OMB

Physics Community

As part of DOE's quest for fusion, Sandia wants a bigger pulsed power machine. The debate heats up on whether pulsed power will surpass lasers in fusion energy production and undercut them in price.

Arecibo Observatory and Motorola strike deal for sharing the spectrum.

OSA and SPIE consider a merger.

Kennicutt is new AAS vice president.

. . . and Brian makes seven.

Web Watch

Books

Tibaldo and the Hole in the Calendar, A. Shimony (reviewed by N. D. Mermin)

Physics in the Nineteenth Century, R. D. Purrington (reviewed by L. P. Williams)

Encyclopedia of Acoustics, edited by M. J. Crocker (reviewed by R. T. Beyer)

Electronic Imaging in Astronomy: Detectors and Instrumentation, I. S. McLean (reviewed by G. Walker)

Relativity and Gravitation, P. Tourrenc (reviewed by C. M. Will)

Atlas of Galactic Neutral Hydrogen, D. Hartmann and W. B. Burton (reviewed by F. J. Kerr)

Simulations for Solid State Physics: An Interactive Resource for Students and Teachers, R. H. Silsbee and J. Drager (reviewed by I. K. Schuller and D. A. Rabson)

X-Ray Binaries, edited by W. H. G. Lewin, J. van Paradijs and E. P. J. van den Heuvel (reviewed by C. Jones)

The Role of the Sun in Climate Change, D. V. Hoyt and K. H. Schatten (reviewed by E. A. Bering III)

Shadow of a Star: The Neutrino Story of Supernova 1987A, A. K. Mann (reviewed by E. W. Kolb)

Plus...

Our regular sections: Physics Update, Letters, New Products, We Hear That, and Information Exchange.