CPT

Calendar of Physics Talks Vienna

Quantum theory of the classical
Speaker:Wojciech H. ZUREK (Los Alamos National Laboratory)
Abstract:I will describe three insights into the transition from quantum to classical. I will start with (i) a minimalist (decoherence-free) derivation of preferred states. Such pointer states define events (e.g., measurement outcomes) without appealing to Born's rule . Probabilities and; (ii) Born’s rule can be then derived from the symmetries of entangled quantum states. With probabilities at hand one can analyze information flows from the system to the environment in course of decoherence. They explain how (iii) robust “classical reality” arises from the quantum substrate by accounting for objective existence of pointer states of quantum systems through redundancy of their records in the environment. Taken together, and in the right order, these three advances elucidate quantum origins of the classical. W. H. Zurek, Nature Physics 5, 181-188 (2009).
Date: Mon, 23.04.2012
Time: 17:30
Location:TU Wien Freihaus, Hörsaal 5, 2. Stock (grüner Bereich), Wiedner Hauptstr. 8, 1040 Wien
Contact:J. Schmiedmayer

Non-Equilibrium Computer Experiments of Soft Matter Systems
Speaker:Arash Nikoubashman (Vienna University of Technology)
Abstract:In this talk, I will present the non-equilibrium characteristics of selected soft matter systems by the means of extensive computer simulations. During the last two decades, the field of soft matter physics developed into a highly active research field, attracting the interest of a vast number of different disciplines, such as chemistry, material science, biology and medicine. Soft matter systems are ubiquitous in our daily lives, ranging from biological matter as DNA, proteins, and blood to man-made substances like liquid crystals, soap and lubricants. In striking contrast to hard matter systems, whose properties are essentially fixed by the electronic structure of the atoms, the situation in soft matter systems is distinctly more complex, since a variety of different length scales are involved and relevant.
Date: Tue, 24.04.2012
Time: 12:30
Duration: 60 min
Location:Vienna University of Technology: Wiedner Hauptstr. 8-10, 10th floor (yellow), seminar room E136
Contact:Vienna Theory Lunch Seminar (http://www.univie.ac.at/lunch-seminar/)

Binding-Activated Localization Microscopy of DNA Structures
Speaker:Dr.sc. ETH Enrico Klotzsch (Technische Universität Wien, Institut für Angewandte Physik)
Abstract:Many nucleic acid stains show a strong fluorescence enhancement when bound to double-stranded DNA. Here we use two different DNA-binding dyes, YOYO-1 and PicoGreen, for superresolution imaging of DNA-structures with binding-acitvated localization microscopy (BALM). Optimization of fluorophore brightness and dynamic labeling conditions yielded a resolution of ~14 nm (FWHM) and a spatial sampling of 1/nm when imaging spin-coated DNA molecules with YOYO-1. BALM with PicoGreen was used to visualize the organization of the bacterial chromosome in fixed Escherichia coli cells with unprecedent resolution. Localization microscopy relies on the separation of the fluorescence emission from individual molecules inside a diffraction-limited spot by sequential excitation. The activation of sparse subsets in PALM, STORM or blinking microscopy achieves this, but suffers from an insufficient ratio between dark and bright fluorophores that limits the labeling density and, finally, the image resolution. Here we alternatively utilize dyes that are ‘switched on’ upon binding to a target structure and localize them under dynamic binding conditions. This method is termed Binding-Activated Localization Microscopy (BALM).
Date: Tue, 24.04.2012
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:Univ.Prof. Dr. Gerhard Schütz

Littrow Lectures 2011/2012 - Massereiche Schwarze Löcher und die Entwicklung von Galaxien
Speaker:Reinhard Genzel ( Max-Planck-Institut für extraterrestrische Physik, Garching)
Abstract:Seit der Entdeckung der Quasare vor etwa 40 Jahren haben sich die Indizien gehäuft, dass in den Zentren von Milchstraßensystemen massive Schwarze Löcher sitzen, die durch Akkretion von Gas und Sternen effizient Gravitationsenergie in Strahlung umwandeln. Durch hochauflösende Messungen im Infrarot- und Radiobereich ist es jetzt im Zentrum unserer eigenen Milchstraße gelungen, einen überzeugenden Beweis für diese Hypothese zu liefern, und gleichzeitig wurden neue und unerwartete Resultate über den dichten Sternhaufen in der unmittelbaren Umgebung des Schwarzen Lochs erbracht. Hierbei haben neue Entwicklungen in der Infrarotinstrumentierung und der adaptiven Optik am neuen Großteleskop der ESO, dem VLT, eine wichtige Rolle gespielt. Gleichzeitig ist es klar geworden, dass die meisten Galaxien massive Schwarze Löcher beherbergen, und dass diese Schwarzen Löcher bereits etwa eine Milliarde ..
Date: Wed, 25.04.2012
Time: 18:15
Location:Festsaal der Österreichische Akademie der Wissenschaften (ÖAW)
Contact:Marianne Baumgart

Lattice QCD calculation of isospin breaking effects due to up-down mass difference
Speaker:Silvano Simula (INFN, Sezione di Roma Tre)
Abstract:im Rahmen des Teilchenphysikseminars
Date: Thu, 26.04.2012
Time: 14:15
Duration: 60 min
Location:Fakultät für Physik, Erwin Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock, 1090 Wien
Contact:H. Neufeld

Volume comparison in Lorentzian manifolds and singularity theorems
Speaker:Jan-Hendrik Treude (Regensburg)
Abstract:im Rahmen des Literaturseminars
Date: Thu, 26.04.2012
Time: 14:15
Duration: 60 min
Location:Arbeitsgruppe: Gravitation, Währinger Strasse 17, Seminarraum A, 2. Stock
Contact:R. Beig

Linear Response Theory
Speaker:Peter Klimek (Med.Univ.Wien)
Abstract:im Rahmen der gemeinsam veranstalteten Seminare "Komplexe Stochastische Systeme" (Univ.Wien) und "Analyse Komplexer Systeme" (Med.Univ.Wien)
Date: Fri, 27.04.2012
Time: 14:15
Duration: 90 min
Location:Medizinische Universität Wien, Informatikbibliothek Bauteil 88, E 03, Spitalgasse 23
Contact:H. Hüffel, Stefan Thurner

Ultra-cold neutrons at FRM II
Speaker:Andreas FREI (FRM II, TU München)
Date: Fri, 27.04.2012
Time: 15:30
Location:TU Wien Atominstitut, Hörsaal, Stadionallee 2, 1020 Wien
Contact:H. Abele