Calendar of Physics Talks Vienna

On the stability of string vacua
Speaker:Magdalena Larfors (LMU Munich)
Abstract:Compactifications of string theory constitute a promising framework for reproducing interesting cosmological features, such as inflation. An important subtlety in these constructions is the stabilization of moduli; four-dimensional scalar fields that describe fluctuations of the geometry of the compactified dimensions. In this talk, I will review how moduli can be fixed in compactifications of type II string theory. I will also discuss cosmological features of the resulting four-dimensional vacua, and how metastable vacua can decay through the formation of new vacuum bubbles.
Overview Lunch Club
Date: Tue, 02.03.2010
Time: 12:30
Duration: 60 min
Location: Vienna University of Technology, Seminar Room E136, 10th floor
Contact:Theo Adaktylos, David Burke, Andreas Gabriel, Niklas Johansson & Christoph Spengler

On the interpretation of recent results on dark matter direct detection
Speaker:Thomas Schwetz (MPI Heidelberg) (Fakultät für Physik)
Abstract:im Rahmen des Teilchenphysikseminars
Date: Tue, 02.03.2010
Time: 16:15
Duration: 60 min
Location:Erwin Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock
Contact:W. Grimus, H. Neufeld

Multi-photon entanglement: High rates and interesting states
Speaker:Witlef Wieczorek (Max Planck Institute of Quantum Optics, Garching, Germany)
Abstract:Multi-partite entanglement plays a decisive role in most quantum information tasks. Thus, the experimental realization of entanglement is crucial for progressing beyond classical information processing. To this end, photons are a leading approach for observing entangled quantum states of multiple qubits. As photon source the non-linear process of spontaneous parametric down conversion (SPDC) driven by ultrashort pump pulses is widely applied. We present a novel SPDC pump source based on a femtosecond enhancement cavity in the ultraviolet wavelength regime. The source increases the available SPDC pump power by more than a factor of five and in this way allows high-rate multi-photon experiments for in-depth state characterizations. The photon source together with a linear optical network is utilized for the observation of symmetric, multi-partite entangled Dicke states. Dicke states are, besides graph states, another important group of states for quantum information processing, for example for telecloning or quantum metrology, which is presented as well.
Date: Wed, 03.03.2010
Time: 11:00
Duration: 60 min
Location:Seminar Room 2.08, IQOQI, Boltzmanngasse 3, 1090 Wien

Topological Strings and the Melting Crystal
Speaker:Paul Schreivogl (Univ. Wien) (Fakultät für Physik)
Abstract:im Rahmen der gemeinsam veranstalteten Seminare "Komplexe Stochastische Systeme" (Univ.Wien) und "Analyse Komplexer Systeme" (Med.Univ.Wien)
Date: Fri, 05.03.2010
Time: 14:30
Duration: 90 min
Location:Erwin Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock
Contact:H. Hüffel