PHYSICS NEWS UPDATE
 A digest of physics news items prepared by
 Phillip F. Schewe, AIP Public Information
 Number 149  October 28, 1993

 THE AMERICAN INSTITUTE OF PHYSICS (AIP) has moved its headquarters to
 College Park, Maryland, just outside Washington, DC.  After 60 years in
 New York City, AIP now occupies a new building, the American Center for
 Physics (ACP), with three of its Member Societies, The American Physical
 Society, the American Association of Physics Teachers, and the American
 Association of Physicists in Medicine.  AIP is a not-for- profit
 corporation chartered for the purpose of promoting the advancement and
 diffusion of the knowledge of physics and its applications; it is the
 largest publisher of physics journals in the world.  PHYSICS NEWS UPDATE
 is prepared by the AIP Public Information division.  Our new address
 (including that of yours truly) is One Physics Ellipse, College Park, MD
 20740-3843; Phone: 301-209-3090; Fax: 301-209-0846; electronic mail:
 pfs2@aip.org

 THE SUPERCONDUCTING SUPER COLLIDER has been emphatically terminated by
 the action of last week's vote in the U.S. Congress.  Denied the research
 tool of their choice, particle physicists must now think of alternatives.
 It's too soon to decide the issue, but two possibilities would be to
 participate substantially in the Large Hadron Collider project proposed
 for CERN in Europe or perhaps to consider building a next-generation
 linear electron-positron collider.

 COLD CESIUM ATOMS BOUNCE UP TO EIGHT TIMES in a new atomic mirror.
 Scientists at the College de France in Paris use evanescent light, the
 electromagnetic field at the surface of a piece of curved glass in which
 laser light is undergoing total internal reflection, to reflect cesium
 atoms dropped from above.  Previous demonstrations of atomic mirrors had
 been limited to one or two bounces. The development of such a mirror is
 the first step toward creating a Fabry-Perot-type interferometer for atom
 waves. (C.G. Aminoff et al., 8 Nov.  Physical Review Letters.)

 THE EXISTENCE OF STABLE STRANGE MATTER, matter containing nuclei whose
 quark inventories include strange quarks, has been hypothesized since the
 1970s.  Such strange matter might exist, perhaps in the form of a
 quark-gluon plasma, in the cores of collapsed stars.  A new theory
 introduced by Carl Dover of Brookhaven (30 August 1993 Physical Review
 Letters) suggests that under some conditions strange baryons (quark
 triplets containing one, two, or even three strange quarks) might clump
 together in large globs. Scientists at Brookhaven will search for evidence
 of the strange-matter states in high-energy collisions between gold
 nuclei.  (Science, 8 Oct. 1993.)

 CARBON AEROGEL properties are in many respects better than those of their
 inorganic counterparts.  Aerogels are microcellular foam materials; they
 are quite porous, low in density (0.1 g/cm**3), and have an area-to-mass
 ratio of 400-1000 m**2/g.  Organic aerogels produced by scientists at
 Lawrence Livermore National Lab have an extremely low thermal
 conductivity, 0.012 watts per meter-kelvin, have greater strength and are
 better electrical conductors than inorganic aerogels, making them
 potentially useful as battery electrodes.  Their pore size, as small as 5
 nm, may make them valuable as gas filters. (Energy & Technology Review,
 May 1993.)