Please join us for coffee and cookies in the kitchen of Hill 705 at
11:45am.
Speaker: S. Olla, Universite Paris Dauphine
Date/Time/Place: Thursday, Nov. 6, 2008, 12:00pm, Hill 705 Title: Pressure models: non-equilibrium behavior Abstract: Pressure models, i.e., one dimensional chains of
unpinned anharmonic oscillators, are the simplest non-linear
mechanical model for the study of 'macroscopic' equilibrium and
non-equilibrium statistical mechanics. The equilibrium statistical
mechanics is particularly simple since it reduces here to the study of
the properties of sums of independent variables. Non-equilibrium
macroscopic evolution, in hyperbolic and diffusive space time scale,
and non-equilibrium stationary states, provide very challenging
problems also in this simplified context. I will translate for this
model, some old and new results, and open problems.
THERE WILL BE A BROWN BAG LUNCH FROM 1PM - 2PM
Speaker: E. Lieb, Princeton University Date/Time/Place: Thursday, Nov. 6, 2008, 2:00pm, Hill 705 Title: Some extensions of Lieb-Thirring inequalities of eigenvalues of the Shroedinger operator Abstract: The LT inequalities bound sums of negative
eigenvalues by certain integrals of the potential energy
function. Extensions of these inequalities (obtained in joint work
with R. Frank and R. Seiringer) to matrix valued potentials and to
complex-valued potentials will be described.
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PLEASE NOTE:
THE SEMINAR FOR THURSDAY, NOVEMBER 13TH HAS BEEN CANCELED.
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Speaker: R. McPherson, IAS Date/Time/Place: Thursday, Nov. 20, 2008, 12:00pm, Hill 705 Title: The geometry of polycrystalline materials Abstract:
A metal or ceramic is naturally decomposed into cells called "grains", each of which is a single crystal. The geometry of this cell complex influences the properties of the material. Some interesting mathematical problems arise in trying to understand the time evolution of these grains. In 1952, Von Neumann gave a simple formula for the growth rate of a grain in 2 dimensions, which has been used as the basis for much of the work on grain evolution. This formula will be generalized to 3 (and higher) dimensions (joint work with David Srolovitz).
THERE WILL BE A BROWN BAG LUNCH FROM 1PM - 2PM
Speaker: R. Seiringer, Princeton University Date/Time/Place: Thursday, Nov. 20, 2008, 2:00pm, Hill 705 Title: Coherent States in Quantum Statistical Mechanics Abstract: Coherent states go back to the early days of quantum
mechanics and have found use in many problems in quantum physics. We
shall discuss their application in problems in quantum statistical
mechanics and dilute Bose gases in particular. Coherent states can be used to
rigorously justify part of Bogoliubov's theory, where creation and
annihilation operators get replaced by c-numbers. Moreover, they are
essential for understanding the emergence of effective theories on the
macroscopic scale, like the Gross-Pitaevskii equation for rotating
Bose gases in traps.
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Speaker: A. Short, University of Cambridge, UK Date/Time/Place: Tuesday, Nov. 25, 2008, 12:00pm, Hill 705 Title: A quantum approach to thermal equilibrium Abstract: One of the biggest challenges in understanding statistical mechanics is
its use of probabilities, which are usually introduced through ignorance
or time-averaging. Here, I will describe an alternative approach, also
pursued here at Rutgers, in which probabilities arise as an objective
consequence of quantum entanglement. In this context, I will offer a
general and rigorous proof of canonical typicality (that small subsystems
appear canonical for almost all states), and show that even non-canonical
initial states evolve towards equilibrium under very general conditions.
THERE WILL BE A BROWN BAG LUNCH FROM 1PM-2PM
Speaker: P.Garrido, Universidad de Granada Date/Time/Place: Tuesday, Nov. 25, 2008, 2:00pm, Hill 705 Title: A test of the additivity principle for current
fluctuations in a model of heat conduction Abstract:The additivity principle allows to compute the current
distribution in many
one-dimensional (1D)
nonequilibrium systems. Using simulations, we confirm this principle
in the
1D Kipnis-Marchioro-
Presutti model of heat conduction. In this case the current
distribution
shows both Gaussian
and non-Gaussian regimes, and obeys the Gallavotti-Cohen fluctuation
theorem. We confirm the
existence of a well-defined temperature profile associated to a given
current fluctuation. This profile
is independent of the current sign, and this symmetry extends to
higher-order profiles and spatial
correlations. We also show that finite-time joint fluctuations of the
current and the temperature
profile are described by the additivity functional. These results
confirm
the additivity hypothesis as
a general and powerful tool to compute current distributions in many
1D
nonequilibrium systems.
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Date/Time/Place: Thursday, Nov. 27, 2008, 12:00pm, Hill 705 PLEASE NOTE: THERE WILL NOT BE A SEMINAR THIS DAY IN OBSERVANCE OF
THANKSGIVING HOLIDAY