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Calendar of Physics Talks Vienna
| Quantum Monte Carlo simulations of ultracold fermions on optical lattices within dynamical mean-field theory |
| Speaker: | Prof. Nils Blümer (Uni Mainz) |
| Abstract: | Within the last few years, ultracold fermionic atoms
on optical lattices have been established as highly tunable
model systems for strongly correlated materials. Most notably,
the prototypical Mott metal-insulator transition has been
detected recently in binary mixtures of 40K, based on
signals in the double occupancy of lattice sites and on cloud
compressibilities. However, despite significant efforts,
low-temperature ordered phases could not yet be seen in
cold-atom systems.
In my talk, I will first introduce the systems of interest and the
corresponding Hubbard-like models and characterize the relevant
theoretical approaches. In particular, I will discuss recent
developments in quantum Monte Carlo (DMFT) methods for
solving the impurity problems arising within the dynamical
mean-field theory (DMFT). I will, then, present results for
Mott transitions in ternary fermionic mixtures on an optical
lattice, including signatures of an unforeseen
semi-compressible phase [1]. Finally, I will turn to our
recent studies of antiferromagnetic order in harmonically
trapped lattice fermions at low temperatures. As we have
shown, the Néel transition is clearly signaled, in the
strong-coupling regime, by an enhanced double occupancy.
The detailed quantitative predictions possible using our
QMC based implementation of real-space DMFT should
provide essential guidance for experimentalists.
[1] E. V. Gorelik, N. Blümer, Phys. Rev. A 80, 051602(R) (2009).
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| Date: | Mon, 03.05.2010 |
| Time: | 16:00 |
| Duration: | 45 min |
| Location: | Josef-Stefan-Hoersaal Boltzmanngasse 5, 3rd floor, 1090 Wien |
| Contact: | Karsten Held |
| Geometric Langlands duality and physics |
| Speaker: | Karl-Georg Schlesinger (University of Vienna) |
| Abstract: | We review the approach to the geometric Langlands program for algebraic curves via S-duality of an N=4 supersymmetric four dimensional gauge theory, initiated by Kapustin and Witten in 2006. We sketch some of the central further developments. Placing this four dimensional gauge theory into a six dimensional framework, as advocated by Witten, holds the promise to lead to a formulation which makes geometric Langlands duality a manifest symmetry (like coavariance in differential geometry). Furthermore, it leads to an approach toward geometric Langlands duality for algebraic surfaces, reproducing and extending the recent results of Braverman and Finkelberg. |
| Date: | Tue, 04.05.2010 |
| Time: | 12:30 |
| Duration: | 60 min |
| Location: | University of Vienna, Boltzmanngasse 5, 5th Floor, Large Seminar Room |
| Contact: | Theo Adaktylos, David Burke, Andreas Gabriel, Niklas Johansson & Christoph Spengler |
| Modulare Lokalisierung in der Quantenfeldtheorie, II |
| Speaker: | Bernhard Reiter (Univ. Wien) (Fakultät für Physik) |
| Abstract: | im Rahmen des Seminars für Mathematische Physik |
| Date: | Tue, 04.05.2010 |
| Time: | 14:15 |
| Duration: | 60 min |
| Location: | Erwin Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | J. Yngvason |
| The Search for Electric Dipole Moments |
| Speaker: | Peter Fierlinger (TU München) (Fakultät für Physik) |
| Abstract: | im Rahmen des Teilchenphysikseminars |
| Date: | Tue, 04.05.2010 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | G.Ecker, H. Neufeld |
| The boundary of the space of the gravitational degrees of freedom |
| Speaker: | Prof. Niall O´Murchadha (Univ. College Cork, Irland) (Fakultät für Physik) |
| Abstract: | im Rahmen des Literaturseminars |
| Date: | Thu, 06.05.2010 |
| Time: | 13:30 |
| Duration: | 60 min |
| Location: | Währinger Straße 17, 1. Stock, Zimmer 118 |
| Contact: | R. Beig |
| A Multiplex View of Organization and Social Balance in Large-scale Social Networks und Lattice Models as Algebraic Dynamical systems, part II |
| Speaker: | Micheal Szell (Med.Uni Wien) und Martin Göll (Uni Wien) (Fakultät für Physik) |
| Abstract: | im Rahmen der gemeinsam veranstalteten Seminare "Komplexe Stochastische Systeme(Uni Wien) und "Analyse Komplexer Systeme" (Med. Uni Wien) |
| Date: | Fri, 07.05.2010 |
| Time: | 14:30 |
| Duration: | 90 min |
| Location: | Erwin Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | H.Hüffel |
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