CPT

Calendar of Physics Talks Vienna

Device-independent games: randomness good, communication bad
Speaker:Valerio Scarani (National University of Singapore (NUS))
Abstract:Bell's theorem rules out the explanation of quantum correlations through pre-established agreement. Most physicists, including the present speaker, view this result as a confirmation of the existence of intrinsic randomness in nature. In the past five years, this lofty view has developed into an unexpected connection with applied quantum information science, hinting to the possibility of "device-independent certification". In the first half of the talk, I shall review some of these developments. In the second half, I shall try and put myself in the skin of the die-hard of determinism, who have to deny one of the two other assumptions of Bell's theorem. I shall rapidly argue that no scientist can abandon "measurement independence" and shall then focus on abandoning no-signaling. I shall prove a strong result which can be seen as a twin of Bell's theorem: if one tries to explain quantum co
Date: Mon, 17.12.2012
Time: 17:30
Duration: 60 min
Location:Univ. of Vienna, Ernst-Mach Hörsaal, Boltzmanngasse 5, 2nd floor, 1090 Wien
Contact:Dr. Christiane Losert / Univ. of Vienna

Infinite Spin Representations: Geometry and Quantum Fields
Speaker:Christian Köhler (University of Vienna)
Abstract:A recent construction, relating Wigner representations of positive mass to those of infinite spin in a continuous way by using stereographic projection, is presented. In this way all transformations of a particle's internal degrees of freedom assume the form of subgroups of the Möbius group, while its mass is related to the inverse radius of the Riemann sphere. We will relate our findings to the construction of intertwiners in the infinite spin limit.
Date: Tue, 18.12.2012
Time: 12:30
Duration: 60 min
Location:Univ. of Vienna, Faculty of Physics, Boltzmanngasse 5, 5th floor, Erwin Schrödinger Lecture Hall
Contact:F. Brünner, S. Frank, P. Köhler, A. G. Passegger, S. Stetina - www.univie.ac.at/lunch-seminar

Trivialitätskriterien für Wightmanfelder
Speaker:Sebastian Poscher (Univ.Wien)
Abstract:im Rahmen des Seminars für Mathematische Physik
Date: Tue, 18.12.2012
Time: 14:15
Duration: 60 min
Location:Fakultät für Physik, Erwin Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock
Contact:J. Yngvason

Surface Phases on 122 Fe Based Superconductors: An Indication of Charge Density Wave Fluctuations?
Speaker:Prof. Erminald Bertel (Institute of Physical Chemistry, University of Innsbruck)
Abstract:In addition to the cuprate superconductors a second class of unconventional superconductors was discovered in 2006 by Hideo Hasono, the iron-based superconductors. The discovery refueled the quest for a rigorous theory of high-temperature superconductivity. Since in both classes of materials the parent compounds exhibit antiferromagnetic order, which is quenched upon doping, it is widely assumed that antiferromagnetic fluctuations are responsible for the pairing interaction. Recently, scanning tunneling microscopy studies of the cleavage surfaces of so-called 122 Fe based superconductors revealed long-range ordered structures with an unexpected temperature dependence. The observations sparked a controversy about the origin of these surface phases. We have found a similar anomalous phase transition in a much simpler system, i.e. halogens on the strongly anisotropic Pt(110) surface. Here
Date: Tue, 18.12.2012
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. Josef Redinger

Constrainted propagation of spherically symmetric Einstein-Yang-Mills fields out to Scri
Speaker:Vincent Moncrief (Yale)
Abstract:Joint seminar with the ESI workshop on dynamics on general relativity
Date: Wed, 19.12.2012
Time: 14:00
Duration: 60 min
Location:ESI Erwin Schrödinger Institut, Boltzmanngasse 9, 2. Stock, 1090 Wien
Contact:P. Chrusciel