CPT

Calendar of Physics Talks Vienna

Cryptographic application of unitary k-designs: non-malleable encryption and multi-photon encryption
Speaker:Jan Bouda (Brno University) (Fakultät für Physik)
Abstract:Vortrag
Date: Mon, 14.12.2009
Time: 18:00
Duration: 60 min
Location:Erwin Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock
Contact:M. Huber

Vienna Theory Lunch Club - Recent Results on the Beta Decay of the Neutron
Speaker:Mario Pitschmann (TU Vienna)
Abstract:Results obtained recently and expected in the nearest future of high precision measurements of correlation coefficients and lifetime of the neutron beta decay pose a crucial test for the Standard Model of elementary particle physics. Currently, standard V-A theory allows to obtain the measured neutron lifetime within one standard deviation. Using the expectation values of the necessary Standard Model parameters a discrepancy of 0.8 seconds appears between theoretical and experimental values. In order to obtain such results theoretically one has to take into account radiative corrections to electroweak interactions, contributions of the weak magnetism, proton recoil energy etc. In the next three years new experiments are planned, which should allow to find contributions of new physics related to scalar, tensor and pseudo-scalar extension of the Standard Model and possibly of supersymmetry. Lunch Club Overview
Date: Tue, 15.12.2009
Time: 12:30
Duration: 60 min
Location:TU Vienna, Inst. f. Theoretical Physics, Freihaus, Wiedner Hauptstr. 8-10, 10. OG, SEM136
Contact:Maximilian Attems, David Burke, Marcus Huber, Theo Adaktylos

Der Hawking Effekt
Speaker:Albert Huber & Georg Kopsky (Univ. Wien) (Fakultät für Physik)
Abstract:im Rahmen des Seminars für Mathematische Physik
Date: Tue, 15.12.2009
Time: 14:15
Duration: 60 min
Location:Erwin Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock
Contact:J. Yngvason

Challenges of power transistors for energy efficiency
Speaker:Dr. Thomas Neidhart (Technik Infineon Österreich, Villach/K)
Abstract:The use of power transistors is getting more and more crucial for daily life's energy consumption in private and industrial applications. New power transistor generations give a Ron x A reduction of 30-50% every couple of year and hence significant reduction of energy losses. The energy efficiency market is growing strongly in aspects of energy conversion, here especially for new energy forms as solar, wind etc, but also for AC-DC, DC-DC conversion in charging stations for notebook, handhelds and other energy consumers. An overview will be given over the most important developments for SFETs, IGBT and CoolMos in the last years and the arising challenges there in µ-electronic production. Furthermore an outlook will be given of the importance of new materials for optimized energy efficiency and future concepts.
Date: Tue, 15.12.2009
Time: 16:00
Location:Technische Universität Wien, Institut für Angewandte Physik, Seminarraum 134A, Turm B (gelbe Leitfarbe), 5. OG, 1040 Wien, Wiedner Hauptstraße 8-10
Contact:Ao.Univ.Prof. Dr. Herbert Störi

Berufungsvortrag *) - Nonlinear scattering in acoustic, optical and quantum cavities
Speaker:Stefan Rotter (Technische Universität Wien)
Abstract:A review of recent developments in the field of nonlinear scattering in transport through resonant cavities will be given. In particular, the influence of the scattering dynamics on the shot noise power in the flow of electronic current will be discussed. We will show that the presence of "classical" scattering states in wave transport leads to a sizeable reduction of the noise power. The emergence of such "noiseless" states has many remarkable consequences, ranging from the transport characteristics of nano-wires to the possibility of reflection-less sound transmission across rooms.
*) Professur für Theoretische Physik (Nichtlineare Dynamik und komplexe Systeme)
Date: Wed, 16.12.2009
Time: 14:15
Duration: 60 min
Location:TU Wien, HS 8 Heinz Parkus Hörsaal 1. OG, Stiege VII, Karlsplatz 13
Contact:J. Burgdörfer

Berufungsvortrag *) - Quantum quenches and thermalization in finite one-dimensional systems
Speaker:Marcos Rigol (Georgetown University)
Abstract: Little more than fifty years ago, Fermi, Pasta, and Ulam set up a numerical experiment to prove the ergodic hypothesis for a one-dimensional lattice of harmonic oscillators when nonlinear couplings were added. Much to their surprise, the system exhibited long-time periodic dynamics with no signals of ergodic behavior. Those results motivated intense research, which ultimately gave rise to the modern chaos theory and to a better understanding of the basic principles of classical statistical mechanics. More recently, experiments with ultracold gases in one-dimensional geometries have challenged our understanding of the quantum domain. After bringing a nearly isolated system out of equilibrium, no signals of relaxation to the expected thermal equilibrium distribution were observed. Some of those results can be understood in the framework of integrable quantum systems, but then it remains the question of why thermalization did not occur even when the system was supposed to be far from integrability. In the latter regime, thermalization is expected to occur and can be understood on the basis of the eigenstate thermalization hypothesis. In this talk, we utilize quantum quenches to describe how the transition between thermalization and its absence occurs in finite one-dimensional lattices.
*) Professur für Theoretische Physik (Nichtlineare Dynamik und komplexe Systeme)
Date: Fri, 18.12.2009
Time: 09:00
Duration: 60 min
Location:TU Wien, Seminarraum 134, 5. Stock, gelber Bereich, Wiedner Hauptstraße 8-10
Contact:J. Burgdörfer