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<div class="moz-text-html" lang="x-western"> <tt>Theory Center
Seminar<br>
Monday, May 2, 2011<br>
1:00 p.m. (coffee at 12:45 p.m.)<br>
CEBAF Center, Room L104<br>
<br>
Olga Goulko<br>
University of Cambridge, U.K.<br>
<br>
<b>The Imbalanced Fermi Gas at Unitarity</b><br>
<br>
</tt><tt>Lattice field theory is a useful tool for studying
strongly interacting <br>
theories in condensed matter physics. A prominent example is the
unitary <br>
Fermi gas: a two-component system of fermions interacting with
divergent <br>
scattering length. With Monte Carlo methods this system can be
studied <br>
from first principles. In the presence of an imbalance (unequal
number of <br>
particles in the two components) a sign problem arises, which
makes <br>
conventional algorithms inapplicable. I will show how to apply
reweighting <br>
techniques to generalize the recently developed worm algorithm
to the <br>
imbalanced case, and present results for the critical
temperature and other <br>
thermodynamic observables at the critical point, namely the
chemical <br>
potential, the energy per particle and the contact density. I
will also <br>
present some preliminary results for these observables at
temperatures <br>
beyond the critical point.</tt> </div>
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