SIGNIFICANT EVENTS  SCIENCE EVENTS
11/21/03
Calculations of Universal Properties near Phase Transition Published
Nikolay V. Prokof'ev of the University of Massachusetts at Amherst reports the
publication of a paper describing his group's calculations for the critical exponents
for a 2dimensional (2D) gas of Bosons. They studied the crossover between the meanfield
and critical behavior of the twodimensional Bose gas throughout the fluctuation region of
the BerezinskiiKosterlitzThouless phase transition point, and established universal
(for all weakly interacting ^{4} models) relations between thermodynamic parameters of the
system, including superfluid and quasicondensate densities. They also developed the
meanfield theory based on the notion of a quasicondensate, which was shown to work
remarkably well outside of the fluctuation region (which now can be characterized quantitatively).
Their results provide the best reference data to compare with and to study interaction effects in
superfluid 2D Bose systems.
These new results are published in "TwoDimensional Weakly Interacting Bose Gas in the
Fluctuation Region", with authors N.V. Prokof'ev and B.V. Svistunov, Phys. Rev. A 66,
043608 (2002).
