CPT

Calendar of Physics Talks Vienna

Interactions of massless bosons in three dimensions
Speaker:Karapet Mkrtchyan (Max-Planck-Institut, Potsdam)
Abstract:im Rahmen des Seminars für Mathematische Physik: I will present the current status of the Noether-Fronsdal program of constructing a classical action for Higher Spin Gravity and discuss the role of special dimensions. In particular, I will provide details on the classification of cubic vertices in three dimensions, which has been completed recently.
Date: Tue, 02.10.2018
Time: 13:45
Duration: 60 min
Location:Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock
Contact:S. Fredenhagen, D. Grumiller

Metal-Organic Frameworks - Synthesis, Characterization and Applications in Separation Science
Speaker:Prof. Dr. Florian Mertens (Institut für Physikalische Chemie der Technischen Universität Bergakademnie Freiberg /Germany)
Abstract:Metal-organic Frameworks or MOFs are a comparable new class of porous crystalline materials that consist of inorganic, often oxidic, network nodes, called secondary building unit (SBU) and organic linkers that interconnect the SBUs. The ease with which these linkers can be modified via organic synthesis allows to generate very specific, highly adjusted materials for applications in gas separation, sensing, and catalysis. Such systematic modification encompasses MOF pore sizes, the chemical environment in the micro-pores, the flexibility of the framework and others. Over the course of almost a decade, the MOF group at the Technical University Freiberg has addressed the determination of fundamental physico-chemical properties of these materials as well as basic principles of the synthesis of the most common representatives of these materials. A particular focus is given on the use of MOFs
Date: Tue, 02.10.2018
Time: 16:00
Location:Technische Universität Wien, Institut für Angewandte Physik, E134 yellow tower „B“, 5th floor, Sem.R. DB gelb 05 B (room number DB05L03), 1040 Wien, Wiedner Hauptstraße 8-10
Contact:Univ.Prof. Markus Valtiner

Inclusive cross sections: localized unitarity and point-by-point cancelations
Speaker:George F. Sterman (SUNY, Stony Brook)
Abstract:1. Vortrag im Rahmen der Schrödinger Gastprofessur 2018: I'll review time- and light-cone ordered perturbation theory as tools for exhibiting the pattern of infrared cancelations in inclusive cross sections.
Date: Tue, 02.10.2018
Time: 16:15
Duration: 90 min
Location:Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock
Contact:A. Hoang, H. Neufeld

Isolated horizons, the Petrov type D equation and the Near Horizon Geometry equation
Speaker:Jerzy Lewandowski (University of Warsaw)
Abstract:3-dimensional null surfaces that are Killing horizons to the second order are considered. They are embedded in 4-dimensional spacetimes that satisfy the vacuum Einstein equations with arbitrary cosmological constant. Internal geometry of 2-dimensional cross sections of the horizons consists of induced metric tensor and a rotation 1-form potential. It is subject to the type D equation. The equation is interesting from the both, mathematical and physical points of view. Mathematically it involves geometry, holomorphic structures and algebraic topology. Physically, the equation knows the secrete of black holes:the only axisymmetric solutions on topological sphere correspond to the the Kerr/Kerr-de Sitter/Kerr-anti-de-Sitter non-extremal black holes or to the near horizon limit of the extremal ones. In the case of bifurcated horizons the type D equation implies another spacial symmetry......
Date: Thu, 04.10.2018
Time: 14:00
Duration: 60 min
Location:Arbeitsgruppe Gravitation, Währinger Strasse 17, Seminarraum A, 2. Stock, 1090 Wien
Contact:P.T. Chrusciel, M. Maliborski

Is de Sitter impossible in String Theory?
Speaker:Thomas Van Riet (Leuven)
Abstract:I will discuss, in pedagogical and broad terms, how string theorist go about to construct meta-stable dS vacua. Then I overview the various potential problems with those constructions and speculate on why it is not unreasonable to think that dS solutions are impossible, they are in the so-called Swampland.
Date: Thu, 04.10.2018
Time: 16:00
Duration: 60 min
Location:Sem.R. DB gelb 10 - Freihaus, TU Wien
Contact:Timm Wrase

Development of Time of Flight MIEZE for Larmor
Speaker:Niels Gereist (TU Delft, Niederlande)
Abstract: A time of flight MIEZE spectrometer, which employs radio frequency spin flippers with square pole shoes and a magnetic yoke is presented. These flippers can achieve higher fields than conventional resonant RF spin flippers, which employ an air core. High fields are crucial for the construction of a high resolution and compact MIEZE spectrometer. Using both types of flippers two MIEZE spectrometer configurations are constructed and compared. Our findings demonstrate that our novel coils can achieve a MIEZE signal, which is similar in quality to a conventional setup. The highest obtained modulation frequency was 100 kHz. Higher frequencies will be obtained on the instrument Larmor at the ISIS pulsed neutron source.
Date: Fri, 05.10.2018
Time: 15:30
Location:Atominstitut, Hörsaal, Stadionallee 2, Wien 2
Contact:St. Sponar