PHYSICS NEWS UPDATE
The American Institute of Physics Bulletin of Physics News
Number 724   March 25, 2005
by Phillip F. Schewe, Ben Stein
        
DIRECT DETECTION OF EXTRASOLAR PLANETS has been achieved for the first
time. Previously the existence of planets around other suns has been
inferred from subtle modulation of the light emitted by the star.  Now
light from the planet itself has been recorded directly at infrared
wavelengths by the Spitzer Space Telescope (www.spitzer.caltech.edu).  The
planets, one with the prosaic name of HD 209458b (153 light years away),
the other TrES-1 (489 light years away), orbit their stars more tightly
than does Mercury around our sun.  This makes the Jupiter-sized planets hot
enough to be viewed by Spitzer.  (NASA press conference, 23 March; report
to be published in Nature, 7 April.)

SUPERFLUID SOLID HYDROGEN.  Quantum science allows for collective behavior
that runs counter to human intuition.  For example, at very low
temperatures helium-4 atoms, in their wavelike manifestation, can begin to
overlap.  When this happens the atoms are indistinguishable and indeed
constitute a single quantum state.  In this state liquid helium-4 will flow
without friction.  Comparably chilled, quantum-condensed dilute gases
(Bose-Einstein condensates, or BEC) also exhibit superfluid behavior.  What
about solids?  Can they "flow" without friction?  Last year Moses
Chan (Penn State) announced the results of an experiment in which solid
helium-4 was revolved like a merry-go-round.  It appeared that when the
bulk was revolved at least part of the solid remained stationary.  In
effect part of the solid was passing through the rest of the solid without
friction.  Chan interpreted this to mean that a fraction of the sample had
become superfluid (see www.aip.org/pnu/2004/split/669-1.html and
www.aip.org/pnu/2004/split/699-2.html).  Now, Chan sees evidence for
superfluid behavior in solid hydrogen as well.  Speaking at this week's
meeting of the American Physical Society (APS) in Los Angeles, Chan said
that his hydrogen results are preliminary and that further checks are
needed to be made before ruling out alternative explanations.  The concept
of what it means to be a solid, Chan said, needs to be re-examined.

HOW EFFECTIVE WILL FLU VACCINE BE?  A new way to study this important issue
is to use the tools of statistical physics.  At the APS meeting, Michael
Deem of Rice University (mwdeem{at}rice.edu) described a new way of predicting
the flu vaccine's efficacy (a higher efficacy means that fewer vaccinated
individuals get the flu relative to unvaccinated individuals).  To measure
efficacy, researchers examine each strain's hemagglutinin (H) protein, the
major protein on the surface of influenza A virus that is recognized by the
immune system.  In one standard approach, researchers study all the
mutations in the entire H protein from one season to the next.  In another
approach, researchers study the ability of antibodies produced in ferrets
to recognize either the vaccine strain or the mutated flu strain, which had
been thought to be a good method for predicting flu vaccine efficacy in
humans.  However, these approaches are only modestly reliable indications
of the vaccine's efficacy.  Deem and his Rice University colleagues point
out that each H protein has 5 "epitopes," antibody-triggering
regions mutating at different rates.  The Rice team refers to the one that
mutates the most as the "dominant" epitope. Drawing upon
theoretical tools originally developed for nuclear and condensed-matter
physics, the researchers focus on the fraction of amino acids that change
in the dominant epitope from one flu season to the next. Analyzing 35 years
of epidemiological efficacy data, the researchers believe that their focus
on epitope mutations correlates better with vaccine efficacy than do the
traditional approaches. Deem and his colleagues Vishal Gupta and Robert
Earl believe that this new measure may prove useful in designing the annual
flu vaccine and in interpreting vaccine efficacy studies.

SOLVAY: THE MOVIE.  Arguably the most famous photograph of physicists is
the group portrait taken at the 1927 Solvay Conference in Belgium.  It
turns out that a brief motion picture of that event also exists.  In the
course of this three-minute film, a dozen or more present and future Nobel
laureates walk in and out of the frame, including Albert Einstein, Marie
Curie, Niels Bohr, and Max Planck.  Forgotten or neglected for decades, the
film was shown in public for the first time at the APS meeting by Nancy
Greenspan, author of "The End of the Certain World," the first
full biography of Max Born (http://www.maxborn.net).  Born is credited with
the insight that the wavefunction appearing in Erwin Schrodinger's famous
equation provided not the exact location of an electron inside an atom but
rather merely a statistical likelihood of the electron being at various
locations.   This view of quantum reality
would later take on the name of the "Copenhagen interpretation,"
in honor of Niels Bohr.  Greenspan argues that Born has been
underappreciated in histories describing the establishment of quantum
science.  Speaking at a  press conference, APS president Marvin Cohen (Univ
California, Berkeley) underscored this point.
Max Born's group at the University of Gottingen, active over the period
from 1922 to 1932, was, Cohen suggested, the most illustrious theoretical
physics "school" of all time.  The list of Born students or
junior colleagues includes no less than Werner Heisenberg, Wolfgang Pauli,
Enrico Fermi, Maria Goeppert-Mayer, Linus Pauling, Eugene Wigner, and
Robert Oppenheimer.

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