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Calendar of Physics Talks Vienna
| Exact solution of quantum field theory toy models |
| Speaker: | Prof. Raimar Wulkenhaar (Mathematisches Inst. der Westfälischen Wilhelms-Univ., Münster) |
| Abstract: | Matrix models share all interesting features of quantum field theory: graphical description
and Feynman rules, power counting dimension, regularisation and renormalisation, divergence of the perturbation series. The first half of the talk will discuss that analogy.
In the second half we report on two matrix models where much more is possible: to give
exact non-perturbative formulae for any renormalised correlation function, or at least their reduction to one new special function. We will also describe a map which projects these matrix correlation functions to Schwinger functions of an ordinary quantum field theory.
We are optimistic that in one of the models the Schwinger 2-point functions satisfies the Osterwalder-Schrader axioms. These results were obtained in joint work with
Harald Grosse and partly with Akifumi Sako.
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| Date: | Tue, 08.11.2016 |
| Time: | 14:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | S. Fredenhagen, H. Grosse |
| Cyclotron resonance in Dirac-type materials |
| Speaker: | Milan Orlita (Laboratoire National des Champs Magnétiques Intenses - Grenoble, CNRS) |
| Abstract: | Cyclotron motion of electrons in a magnetic field, and the related resonant absorption of light at the cyclotron frequency, is probably the most representative magneto-optical effect, characteristic of any solid with non-zero free charge carrier density. In this talk, I will review selected results of cyclotron resonance measurements done on different materials which host conical (Dirac-type) features within their band structures (e.g., single and multilayer graphene, graphite, gapless HgCdTe, HgTe quantum wells). In contrast to conventional systems with parabolic bands, such materials imply fairly complex, in general multimode, cyclotron resonance response, which allows us get relevant insights into the electronic states of these materials, as well as into particular elastic and inelastic (e.g. Auger) scattering mechanisms. |
| Date: | Tue, 08.11.2016 |
| Time: | 15:00 |
| Duration: | 45 min |
| Location: | Seminarraum DC rot 07 (Freihaus, roter Bereich, 7. OG), Wiedner Hauptstraße 8-10, 1040 Wien |
| Contact: | Andrei Pimenov |
| Two puzzles in the beauty sector of QCD |
| Speaker: | Dmitri Melikhov (Uni Wien) |
| Date: | Tue, 08.11.2016 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | H. Neufeld |
| Exotic Charged States of Charmonium and Bottomonium |
| Speaker: | Prof. Dr. Simon Eidelman (Budker Institute of Nuclear Physics SB RAS and Novosibirsk State University) |
| Abstract: | We discuss exotic charged states in heavy quarkonia based on recent experimental observations from Belle, BESIII and LHCb. For charmonium they include studies of Z(4430) at Belle and LHCb as well as studies of Z_c(3900) and Z_c(4020) at BESIII. For bottomonium a discovery of Z_b(10610) and Z_b(10650) at Belle is presented. We also briefly report on the observation of some other exotic states of charmonium. both charged, like X(4050) and X(4250), and neutral, like X(3872), whose nature is not yet completely understood. |
| Date: | Wed, 09.11.2016 |
| Time: | 17:00 |
| Duration: | 60 min |
| Location: | Stefan-Meyer-Institut, Boltzmanngasse 3, 1090 Wien, Seminarraum 3-2-08 (2. Stock) |
| Contact: | Prof. Dr. Eberhard Widmann, Dr. Martin Simon |
| Decoherence due to time dilation |
| Speaker: | Caslav Brukner (Univ. Vienna) |
| Abstract: | im Rahmen des Literaturseminars der Gravitationsphysik |
| Date: | Thu, 10.11.2016 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Arbeitsgruppe Gravitation, Währinger Strasse 17, Raum 218, 2. Stock, 1090 Wien |
| Contact: | P.T. Chrusciel |
| Time dependence of holographic spectral function |
| Speaker: | Lata Joshi (IIT Bombay, India) |
| Abstract: | Using state/geometry map, we have proposed a method to find retarded propagator in generic non-equilibrium states. We discuss the spectral function of a scalar in a class of non-equilibrium states. This class is given in terms of AdS-Vaidya geometry with an arbitrary parameter characterizing the dual state transition from one thermal state to another due to a homogenous quench. In this talk, I will discuss different routes and patterns of spectral function thermalization under various quench duration and scalar momenta. |
| Date: | Thu, 10.11.2016 |
| Time: | 16:00 |
| Location: | SEM 136, TU Wien, Freihaus, 10th floor (Wiedner Hauptstr. 8-10, A-1040 Vienna) |
| Contact: | Ayan Mukhopadhyay |
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