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Calendar of Physics Talks Vienna
| Melting Transitions of Hard Disks |
| Speaker: | Prof. Dr. Werner Krauth (Laboratoire de Physique Statistique, École normale supérieure in Paris Cedex, France) |
| Abstract: | The hard‐disk model has exerted outstanding influence on computational physics and statistical mechanics. Decades ago, hard disks were the first system to be studied by Markov-chain Monte Carlo methods and by molecular dynamics. It was in hard disks, through numerical simulations, that a two-dimensional melting transition was first seen to occur even though such systems cannot develop long‐range crystalline order. Analysis of the system was made difficult by the absence of powerful simulation methods.
In recent years, we have developed a number of powerful Monte Carlo algorithms for hard disks and related systems. I will in particular show how the powerful event-chain Monte Carlo algorithm which has allowed us to prove that hard disks melt with a first-order transition from the liquid to the hexatic and a continuous transition from the hexatic to the solid. |
| Date: | Mon, 23.01.2012 |
| Time: | 16:00 |
| Location: | SemR 138C, TU Wien, |
| Contact: | SC-CMS / CMS / ViCoM |
| Neutron Stars as Laboratory for Dense Matter |
| Speaker: | Laura Tolos (Universidad Autonoma de Barcelona) |
| Abstract: | Neutron stars are an excellent laboratory for testing matter under extreme conditions. In particular, a lot of emphasis has been invested in understanding the interior of neutron stars and the equation of state of the different possible phases since its direct consequences for the mass-radius relationship of neutron stars as well as cooling processes. I will review some results for nucleonic, kaonic and hyperonic matter together with superfluidity and their consequences for cooling processes. I will comment on possible constraints not only from neutron stars observations but also from back-to-Earth experiments, such as heavy-ion collisions. I will finally outline future prospects to be tested in neutron stars laboratory. |
| Date: | Tue, 24.01.2012 |
| Time: | 12:30 |
| Duration: | 60 min |
| Location: | TU Wien (Wiedner Hauptstrasse 8-10/136, 1040 Wien, yellow area, 10th floor, seminar room 136) |
| Contact: | Sabine Ertl |
| Bose-Einstein Kondensation in niedrigen Dimensionen |
| Speaker: | Veronika Baumann (Univ.Wien) |
| Abstract: | im Rahmen des Seminars für Mathematische Physik |
| Date: | Tue, 24.01.2012 |
| Time: | 15:30 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock, 1090 Wien |
| Contact: | J. Yngvason |
| Quantum Matter with Strong Correlations - From Hot Superconductors to Cold Atoms |
| Speaker: | Prof. Dr. Antoine Georges (Centre de Physique Théorique, Collége de France and École Polytechnique in Palaiseau Cedex, France) |
| Abstract: | From copper-oxide superconductors to rare‐earth compounds, materials with strong electronic correlations have focused enormous attention over the last two decades. Solid‐state chemistry, new elaboration techniques and improved experimental probes are constantly providing us with examples of novel materials with surprising electronic properties, the latest example being the recent discovery of iron-based high-temperature superconductors.
In this colloquium, I will emphasize that the classic paradigm of solid-state physics, in which electrons form a gas of wave-like quasiparticles, must be seriously revised for strongly correlated materials. Instead, a description accounting for both atomic-like excitations in real‐space and quasiparticle excitations in momentum space is requested. I will review how Dynamical Mean-Field Theory - an approach that has led to significant advances in our understanding of strongly correlated materials - fulfills this goal.
New frontiers are also opening up, which bring together condensed-matter physics and quantum optics. `Artificial materials' made of ultra-cold atoms trapped by laser beams can be engineered with a remarkable level of controllability, and allow for the study of strong-correlation physics in previously unexplored regimes. |
| Date: | Tue, 24.01.2012 |
| Time: | 17:15 |
| Location: | Lecture Hall P2, Graz University of Technology (TU Graz), Petersgasse 16, A-8010 Graz, AUSTRIA |
| Contact: | SC-CMS / CMS / ViCoM |
| Quarkonium Phenomenology in Vacuum |
| Speaker: | Denis Parganlija (Vienna University of Technology) |
| Abstract: | The scalar mesons have been one of the most debated issues of
low-energy QCD for decades. The experimental data show the existence of
six scalar isosinglet states - next to the famous sigma meson, there are
five states with the same quantum numbers but higher energies than the
energy of the sigma. If we consider the u and d quarks as degenerate and
work in a theoretical framework that inlcudes strange states as well,
then we can construct two scalar \bar q - q states. Thus constructed
scalars can, of course, describe at most two out of the mentioned six
experimentally known states - but the question is: Which two?
I will present a model with (pseudo)scalar and (axial-)vector mesons that
allows us to answer this question. The scalar (and other) mesons are
important not only in vacuum but also at finite temperatures and densities
as they build order parameters for the chiral transition. |
| Date: | Thu, 26.01.2012 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | SEM 136 (Freihaus, Wiedner Hauptstrasse 8-10), Institute for Theoretical Physics, Vienna University of Technology |
| Contact: | Andreas Schmitt |
| Nonrelativistic high-energy physics: Precision calculations for top and squark production at the LHC |
| Speaker: | Martin Beneke (RWTH Aachen) |
| Abstract: | im Rahmen des Teilchenphysikseminars |
| Date: | Thu, 26.01.2012 |
| Time: | 14:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock, 1090 Wien |
| Contact: | A. Hoang, H. Neufeld |
| On the asymptotic dynamics of G2 cosmologies |
| Speaker: | Mark Heinzle (Univ.Wien) |
| Abstract: | im Rahmen des Literaturseminars |
| Date: | Thu, 26.01.2012 |
| Time: | 14:15 |
| Duration: | 60 min |
| Location: | Arbeitsgruppe: Gravitation, Währinger Strasse 17, Seminarraum A, 2. Stock |
| Contact: | R. Beig |
| Progress Report on Group Formation and Dynamics in the Pardus Game |
| Speaker: | Benedikt Fuchs (Med.Univ. Wien) |
| Abstract: | im Rahmen der gemeinsam veranstalteten Seminare "Komplexe Stochastische Systeme"(Univ.Wien) und "Analyse Komplexer Systeme" (Med.Univ.Wien) |
| Date: | Fri, 27.01.2012 |
| Time: | 14:15 |
| Duration: | 90 min |
| Location: | Medizinische Univ., Bauteil 88, |
| Contact: | H. Hüffel, Stefan Thurner |
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