PHYSICS NEWS UPDATE

THE AMERICAN INSTITUTE OF PHYSICS

BULLETIN OF PHYSICS NEWS


Number 331 July 24, 1997 by Phillip F. Schewe and Ben Stein

THE CHAOTIC MOTION OF DISKS sinking in a fluid can be mapped onto a diagram whose parameters reflect the density and viscosity of the fluid and the size and density of the disk. A Colorado State/Michigan collaboration has discovered that the disk trajectories (videotaped and anatomized into numerical coordinates) are of four types: steady falling, tumbling, periodic oscillating, and an unpredictable chaotic mode. (Stuart Field et al., Nature, 17 July 1997.)


Other items covered in the same issue of Physics New Update:

CHAOS CONTROL OF EL NINO in a sophisticated computer simulation has been achieved by an Israel-US team.

ASTEROID MATHILDE, viewed from a distance of only 1200 km by the Near- Earth Asteroid Rendezvous (NEAR) space probe, is heavily cratered from millions of years of rough travel through the solar system.

CANCER-FIGHTING RADIOACTIVITY can be made safer and more efficient by using antibodies to carry tailored isotopes directly to cancer cells, thus zapping bad cells with targeted doses of ionizing radiation while sparing healthy cells.