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news release:
Biggest physics meeting of the year
Baltimore, MD, Mar. 17: The American Physical
Society (APS)
March Meeting,
usually the biggest physics meeting of the year anywhere, will occur this year
March 13-17 at the Baltimore Convention Center by the harbor in Baltimore,
Maryland. The March APS Meeting has traditionally been the showcase for the kind
of cutting-edge research results that appear, sometimes not so long afterwards,
in the new electronic, communications, computer, and medical diagnosis products
that have done so much to shape modern culture.
Over 6500 papers will be delivered, some of them
in prestigious invited-paper sessions, some in sessions of shorter 10-minute
talks, and some in the form of posters. The large disciplinary areas at the
meeting will be condensed matter physics, biological physics, chemical physics,
new materials, fluid dynamics, polymers, and large-scale computing. Many of the
presentations concern fundamental physics discoveries, while many others will
look at the progress made toward implementing scientific discoveries in
practical devices.
The March Meeting is a place where the latest
developments in leading physics research areas (e.g., superconductivity,
nanotubes, superfluids, quantum information, ultracold atoms) are reported and
where whole new subjects are represented for the first time (e.g., fast
electrons in graphene, session D2). The diversity of session subjects is
abundant: planetary interiors (A42), ultrafast chemistry (R13), liquid splashing
(P8), biological swarming (G8), optical clocks (K1), snake infrared vision
(Y26), nanoplumbing (N26.4), Bose-Einstein transistors (B43.10), serial
crystallography (A29.11), microscale synthetic swimmers (B29.2),
plastic-explosive-degrading enzyme (P26.4), Cooper-pair molasses (Z39.11),
double electromagnetically induced transparency (N43.1), vortex-phase qubits
(B43.13), novel skin cream (C1.131), and antimicrobial coatings for medical
devices (G29.5).
A Nobel Prize symposium (session G1a) entitled
"One Hundred Years of Light Quanta" will feature all three winners of the most
recent physics prize (Ted Haensch, John Hall, Roy Glauber) and at least one talk
(Serge Haroche, K1.5) will describe how the prizewinning work still manifests
itself in modern experiments.
Not all the sessions are technical in nature.
Session H4a looks at Renaissance art (did painters use optical devices to
achieve "realistic" effects?) and Broadway theater (science- and math-related
themes). Other topics with social implications include Intelligent Design (M50,
Tuesday night, March 14---see below), nuclear proliferation and terrorism (B5),
US technology in the age of globalization (N5), how to be a referee (N34), the
foundations of evolution (R7---see below), the use of complexity theory on Wall
Street (A33, B33) and in studying population dynamics (Z28), and issues relating
to university physics departments including the status of women, curricula
trends, foreign students, and ethics (H5).
SINGLES' BAR FOR SPINS
Rice and MIT researchers will present ongoing investigations of an unusual
superfluid phenomenon in gases of ultracold fermions such as lithium-6. Because
fermions are one of the fundamental building blocks of matter, the new research
may bear on diverse phenomena ranging from superconductivity to the dense quark
matter at the core of neutron stars. Conventional theory says that
superconductivity requires an equal number of spin-up and spin-down particles,
similar to requiring an equal number of men and women at a dance hall. Using
ultracold atomic gases consisting of spin-up and spin-down atoms, physicists can
now test what happens when this condition is not met in superfluidity, the
analog of superconductivity for particles without an electric charge. By
observing superfluid vortices in an unequal mixture of lithium-6 atoms, Wolfgang
Ketterle and his colleagues at MIT have shown that superfluidity persists even
when there are unequal numbers. Only when there are too many unpaired loners
(the single men) in the room, the situation becomes uncomfortable for the
couples and superfluidity breaks down. At Rice University, Randy Hulet and his
colleagues have shown that beyond a critical mismatch the unpaired loners are no
longer tolerated and are suddenly expelled from a uniformly paired core to a
surrounding shell containing the excess unpaired atoms (so that a wall of
singles surrounds the paired-up couples). For a small number of excess unpaired
atoms, however, the Rice group reports evidence of a uniform superfluid, i.e.,
the couples accommodate the presence of the single men on the dance floor. The
nature of this lastly mentioned state is especially enigmatic, and may involve
some exotic, new form of superfluidity. (Papers H6.3 and D43.4)
TOPSY-TURVY SUPERCONDUCTIVITY
When a superconducting zinc nanowire is attached to bulk superconducting leads
of another material, one would expect that the wire remains superconductive. In
a recent experiment at Penn State, Minglian Tian and his colleagues (Moses Chan)
observed that when the wire was connected to superconducting leads consisting of
indium or tin, its superconductivity is suppressed. Bizarrely, when the indium
or tin attachments were driven into a non-superconducting state, the
superconductivity in the zinc nanowire recovers. (A1.2)
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