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Calendar of Physics Talks Vienna
| Entanglement structure of complex quantum systems |
| Speaker: | Norbert Schuch (JARA /RWTH Aachen) |
| Abstract: | Complex quantum systems exhibit a variety of unconventional phenomena,
such as protected quantized edge currents or excitations with non-trivial
statistics. These phenomena are rooted in the complex global entanglement
structure present in those systems, referred to as topological order. In
this talk, I will explain how one can model the physics of such systems
based on their entanglement structure in a way which allows to reconcile a
local description with global entanglement, and to understand the
emergence of global order from local properties. In particular, I will
discuss how the local symmetry structure of the system can give rise to
global topological order, and the way in which this order shows up in the
edge physics and the entanglement properties of the system.
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| Date: | Mon, 25.04.2016 |
| Time: | 17:30 |
| Duration: | 60 min |
| Location: | HS 7, Schütte-Lihotzky, Karlsplatz 13, Vienna |
| Contact: | www.coqus.at / Christina Becker |
| All you need is light: Photochemistry from first principles |
| Speaker: | Univ.Prof. Dr. Leticia González (University of Vienna, Institute of Theoretical Chemistry) |
| Abstract: | One particular challenge of Chemistry is to understand processes driven by light [1]. From the theoretical point of view, the study of photochemistry means calculating electronically excited states but also investigating the relaxation pathways that a molecule follows after being illuminated with light. Only after the natural dynamics of a molecular system is explained it is even possible to manipulate light-induced processes using light particularly shaped. In our group we employ ab initio quantum chemical methods, typically multiconfigurational ones, to first explore the excited states which are populated after a system is irradiated, and then to characterize the potential energy surfaces that the molecule can visit induced by light. A more detailed picture of the light-induced relaxation pathways is obtained with a time-dependent analysis. Here we employ ab initio molecular dynamics, |
| Date: | Tue, 26.04.2016 |
| 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. Dr. Ulrike Diebold |
| The anomalous magnetic moments of the light charged leptons: precision tests of the standard model |
| Speaker: | Marc Knecht (CNRS Marseille) |
| Abstract: | im Rahmen des Teilchenphysikseminars |
| Date: | Tue, 26.04.2016 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | G. Ecker, H. Neufeld |
| The anomalous magnetic moments of the light charged leptons: precision tests of the standard model |
| Speaker: | Marc Knecht (CNRS Marseille) |
| Date: | Tue, 26.04.2016 |
| Time: | 16:15 |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | G. Ecker, H. Neufeld |
| Self-interacting dark matter: from astrophysical observations to particle physics |
| Speaker: | Xiaoyong Chu (ICTP Trieste) |
| Abstract: | Standard Cosmology have been proven to provide a successfully framework to describe evolution of the Universe, allowing to test new particle physics with astrophysical observations. Among them, the possibility of self-interacting dark matter (SIDM) is particularly appealing, as a solution to several astrophysical problems. In the talk, I will discuss the motivations of SIDM, the particle physics to realize SIDM models, and some potential problems related. This talk is based on 1510.08063, 1510.08527, and on-going work. |
| Date: | Wed, 27.04.2016 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | HEPHY, Nikolsdorfer Gasse 18, Library |
| Contact: | Josef Pradler |
| Laser-induced periodic surface structures: Formation mechanisms, characteristics and applications |
| Speaker: | MSc Nathala Chandra S.R. (TU Wien, Insitut für Angewandte Physik, AG Atom- und Plasmaphysik) |
| Abstract: | Laser-induced periodic surface structures (LIPSS or ripples) appear on all kinds of materials: dielectrics, semiconductors, polymers and metal surfaces, when exposed to single or multiple ultra-short laser pulses. The formed periodic structures have two sets of periods1. One set of periods is close to the wavelength of the laser radiation and the other set has periods close to 1/10th of the wavelength of the incident radiation. The field has recently gained remarkable interest as they can be generated in a single-step process and allows a wide range of surface functionalization. Possible applications include colorization, control of surface wetting behaviour and friction management. In this seminar, I will talk about the formation mechanisms of LIPSS, results of our experiments and current state-of-the art applications of LIPSS.
1 C. S. R. Nathala, A. Ajami, A. A. Ionin, S. I. Kudryasho |
| Date: | Wed, 27.04.2016 |
| Time: | 16:00 |
| Location: | Technische Universität Wien, Institut für Angewandte Physik, E134 red tower „C“, 5th floor, meeting room (room number DC05E22), 1040 Wien, Wiedner Hauptstraße 8-10 |
| Contact: | Ao.Univ.Prof. Dr. Wolfgang Husinsky |
| Vector field methods for relativistic transport equations and applications |
| Speaker: | Jacques Smulevici (U Paris-Sud) |
| Abstract: | im Rahmen des Literaturseminars der Gravitation: I will present recent results obtained in collaboration with D. Fajman and J. Joudioux concerning the study of relativistic kinetic equations via techniques inspired by the traditional vector field method of Klainerman. In the second part of my talk, I will give some applications to systems of relativistic transport equations coupled to wave equations, such as the Vlasov-Nordström system.
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| Date: | Thu, 28.04.2016 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Arbeitsgruppe Gravitation, Währinger Strasse 17, Seminarraum A, 2. Stock, 1090 Wien |
| Contact: | D. Fajman, J. Joudioux |
| Initial state and pre-equilibrium effects in small systems |
| Speaker: | Sören Schlichting (Brookhaven National Laboratory) |
| Abstract: | A surprising discovery in high-multiplicity proton-proton (p + p) and proton-nucleus (p + A) collisions at the LHC was the observation of pronounced azimuthal correlations between produced particles. In this talk I will discuss the importance of initial state and early time effects with regard to the theoretical understanding of these long range azimuthal correlations. |
| Date: | Thu, 28.04.2016 |
| Time: | 16:00 |
| Duration: | 60 min |
| Location: | Seminar room DB-gelb-10, 10th floor, TU Wien, Wiedner Hauptstr. 8-10, 1040 |
| Contact: | Andreas Ipp |
| A Toy Model of Black Hole Complementarity |
| Speaker: | Dr Souvik Banerjee (VSI, University of Groningen, Netherlands) |
| Abstract: | We consider the algebra of simple operators defined in a time band in a CFT with a holographic dual. The action of these operators on the CFT vacuum can generate all low energy states in the CFT, and no operator within the algebra can annihilate the vacuum. For a time band smaller than the light crossing time of AdS, local excitations within the causal diamond in the centre of AdS are invisible to the algebra of simple operators on the boundary by causality. However, we show that if one goes beyond this algebra by considering all possible boundary operators inside the time band, it is possible to reconstruct local physics inside the diamond as well. Our construction therefore provides a toy model of black hole complementarity. |
| Date: | Fri, 29.04.2016 |
| Time: | 09:00 |
| Duration: | 60 min |
| Location: | 3rd floor seminar room, yellow tower, ITP, TU Wien, Wiedner Hauptstrasse 8-10, A-1040 Vienna |
| Contact: | ayan@hep.itp.tuwien.ac.at |
| Low Frequency Gravitational Wave Detection with Ground Based Atom Interferometer Arrays |
| Speaker: | Remi Geieger (SYRTE, Observatoire de Paris) |
| Abstract: | After more than 20 years of fundamental research, atom interferometers have reached sensitivity and accuracy levels competing with or beating inertial sensors based on different technologies. Atom interferometers offer interesting applications in geophysics (e.g. detection of sub-surface mass transfers), inertial sensing, metrology and tests of fundamental physics. Recently, a growing interest for the application of atom interferometry to gravitational wave detection has been drawn.
During this seminar, I will present a new detection strategy for gravitational waves (GWs) below few Hertz based on a correlated array of atom interferometers (AIs) [1]. The method allows to reject the Newtonian Noise which represents a fundamental limit to all ground based GW detectors below few Hertz, including previous AI-based concepts. Using an array of long baseline AI gradiometers yields several estimations of the Newtonian Noise, whose effect can thus be reduced via statistical averaging. Exploiting the correlation properties of the gravity acceleration noise, I will show that a 10-fold or more Newtonian Noise rejection is possible with a dedicated configuration. Considering the current developments in cold atom technology, I will show that strain sensitivities below 1×10−19 /√Hz in the 0.3-3 Hz frequency band can be within reach, with a peak sensitivity of 3×10−23 /√Hz at 2 Hz. The proposed configuration could extend the observation window of current detectors by a decade and fill the gap between ground-based and space-based instruments.
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| Date: | Fri, 29.04.2016 |
| Time: | 15:30 |
| Location: | Atominstitut, Hörsaal, Stadionallee 2, Wien 2 |
| Contact: | J. Schmiedmayer |
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