Number 134, June 24, 1993 by Phillip F. Schewe and Ben Stein
FERMAT'S LAST THEOREM HAS BEEN PROVED . Posed in 1637 by the French mathematician
and physicist Pierre de Fermat just before he died, the theorem states
that the equation x**n + y**n = z**n (where x, y, and z are positive integers
and n in an integer greater than 2) has no solution. Andrew Wiles of Princeton
University announced the proof (yet to be published and checked by others)
yesterday at the end of a lecture at Cambridge University in the UK. (The
New York Times, 24 June 1993.)
AN EXPLANATION IS EMERGING FOR SONOLUMINESCENCE , the mysterious underwater
phenomenon in which air bubbles, compressed by sound waves, implode, releasing
50-picosecond flashes of light which are up to a trillion times more concentrated
in energy than the initial sound waves. A new round of experiments and
calculations over the last year has done much to elucidate the details
of the phenomenon. C.C. Wu and Paul Roberts of UCLA propose (in the 31
May Physical Review Letters) that the mechanism for sonoluminescence consists
of spherical shock waves generated in the collapsing bubble. According
to the hypothesis, the shock waves travel to the bubble's center at supersonic
speeds, compressing air inside the bubble and heating it to such high temperatures
(over 5000 K) that a plasma is formed. Electrically charged particles in
the plasma release flashes of light in the process of accelerating. (The
Sciences, July/August 1993.)
SINGLE-LAYER CARBON NANOTUBES have been mass-produced by scientists
at IBM-Almaden and NEC Corporation in Japan working independently. Previous
methods of mass-producing carbon nanotubes, the all-carbon tubular structures
with widths on the nanometer scale, resulted in nanotubes of various sizes,
usually having multilayered shells of carbon atoms. However, when metal
catalysts (and for the NEC researchers, a methane-argon gas mixture) were
added to the graphite electrodes traditionally used to make the nanotubes,
batches of uniform thickness resulted. Electron diffraction studies revealed
that the nanotubes had widths in the 1 nm range, corresponding to a single-atom
thickness. Producing single-layer nanotubes in bulk will allow for better
tests of theory. (S. Iijima et al.; D.S. Bethune et al, Nature, 17 June
1993; Science News, 19 June 1993.)
THE U.S. DEPARTMENT OF ENERGY BUDGET request for fiscal year 1994 for
various categories (in millions of dollars): 640 for SSC; 628 for high
energy physics, including 141 for Fermilab, 80 for SLAC, and 43 for BNL
operating expenses, 25 for the Fermilab main injector, and 36 for a B factory
(to be built at SLAC or Cornell); 322 for nuclear physics, including 70
for RHIC; 802 for basic energy sciences, including 143 for materials science,
134 for facilities operations, including new synchrotron light sources
at Berkeley and Argonne; 119 for construction, mostly for the Argonne light
source; 348 for (mostly magnetic) fusion energy; and 188 for inertial-confinement
fusion. The FY94 NASA budget request for some specific physics-related
items: 1075 for physics and astronomy, including 260 for AXAF, 40 for Gravity
Probe-B, 261 for Hubble operations and data analysis; 557 for planetary
exploration, including 206 for Cassini development, 57.6 for Galileo and
34 for Mars Observer. (Physics Today, June 1993.)
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