CPT

Calendar of Physics Talks Vienna

Information causality
Speaker:Prof. Marek Zukowski (University of Gdansk, Poland)
Abstract:Special relativity is derived from assumptions which are meaningful statements about the structure of the universe we live in, while the standard postulates of quantum mechanics describe only the mathematical formalism, and its relation with experimental observations. Is it possible to derive quantum mechanics from theory independent statements? A principle that has been proved useful in deriving some of the properties of quantum mechanics is no-signaling. Yet, we know that this principle alone is too weak to single out quantum theory. The most prominent example, for the case where it fails in this respect, is the amount of violation by quantum correlations of the Bell-CHSH inequality (which is satisfied by all possible classical theories). Non-signaling theories can violate such inequalities much more strongly than quantum correlations, which never breach the so-called Tsirelson bound. This is where our new principle of Information Causality [5] comes into play. It is basically no-signaling condition, albeit with an additional requirement (see below), which seems natural, nevertheless thus far it has not been formulated. Still, it drastically narrows the range of possible theories of Nature. We show that it can be used to derive the quantum mechanical Tsirelson bound, without invoking quantum theory at any stage. Information Causality can be phrased as follows: If some receiver gets m classical bits of information, his knowledge cannot increase by more than m bits, and it is only the sender, not the receiver, who can choose (before the bits are sent) what this knowledge is about.
Date: Mon, 08.03.2010
Time: 17:30
Duration: 60 min
Location:Schütte-Lihotzky-Hörsaal 7, Karlsplatz 13, Hof 2, 1040 Wien
Contact:Prof. Caslav Brukner

Deformationsquantisierung und Deformationen von Quantenfeldtheorien
Speaker:Gandalf Lechner (Univ. Wien) (Fakultät für Physik)
Abstract:im Rahmen des Seminars für Mathematische Physik
Date: Tue, 09.03.2010
Time: 14:15
Duration: 60 min
Location:Erwin Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock
Contact:J. Yngvason

Recent advances in the synthesis of Al2O3 coatings
Speaker:Prof. Dr. Christian Mitterer (Department of Physical Metallurgy and Materials Testing, University of Leoben)
Abstract:Al2O3 coatings are widely used for wear and oxidation protection of cutting tools. While high-temperature chemical vapor deposition (CVD) at temperatures of ~1000°C is an industrial standard for depositing the stable α-Al2O3 and the metastable κ-Al2O3 phases on thermally stable cemented carbide cutting tools, recently physical vapor deposition (PVD) processes have been introduced to synthesize different Al2O3 phases in the temperature range between 500 and 700°C. The present talk reviews aspects of thermal stability of metastable κ-Al2O3 coatings grown by CVD and metastable γ-Al2O3 / amorphous Al2O3 structures synthesized by pulsed magnetron sputtering, where it could be shown that these metastable coatings are stable up to more than 1000°C. Furthermore, attempts to improve the mechanical properties of CVD α-Al2O3 coatings by Ti doping and to stabilize the α-Al2O3 phase by addition of Cr2O3 in a cathodic arc evaporation process are presented.
Date: Tue, 09.03.2010
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