CPT

Calendar of Physics Talks Vienna

2d flat space holography and warped-Schwarzian theory
Speaker:Hamid Afshar (TU Wien)
Abstract:The Sachdev-Ye-Kitaev (SYK) model is an interacting statistical quantum mechanical model. In low temperature this model has a (1+1)-dimensional dilaton-gravity description in AdS_2 spacetime known as Jackiw–Teitelboim model. The key link between gravity and quantum theory side is the boundary effective action denoted as "Schwarzian theory". In this talk after reviewing this construction we set up this correspondence in the case of (1+1)-dimensional dilaton-gravity in flat spacetime and derive the analogous boundary action which coincides with the one discovered recently in1908.08089 as "warped Schwarzian theory".
Date: Tue, 22.10.2019
Time: 13:45
Duration: 60 min
Location:TU Wien - Wiedner Hauptstraße 8 - Red Area, 7th floor, Seminar Room (DC 07 A15)
Contact:D. Grumiller, S. Fredenhagen

Theoretical studies of protein aggregation
Speaker:Andrij Baumketner (NAS of Ukraine)
Abstract:Protein aggregation refers to the proces of self-assembly of fully or partially unfolded proteins that leads to the formation of large insoluble complexes, aggregates. One type of protein aggreates – amyloid fibrils is implicated in various neurodegenertive diseases and also has found multiple uses in technology. We will discuss what can be learned about amyloid using theoretical models and methods. We will start with a broad overview of problems and challenges facing theoretical approaches, from the description of small oligomers, which are often considered kinetic intermediates to fibrils, to particlar details of amyloid structure. Later on we will focus on aggregation pathway of the peptide involved in Alzheimer’s disease. Finally, we will present a model specifically designed for simulation of protein aggregates and discuss the effect of electric field on amyloid assembly.
Date: Tue, 22.10.2019
Time: 14:00
Duration: 60 min
Location:TU Wien, Inst.f.Theoretical Physics, 1040 Wien, Wiedner Hauptstraße 8-10, yellow tower, 10th floor, Seminar Room
Contact:G. Kahl

Non-clinical Research Opportunities at MedAustron
Speaker:Albert Hirtl (TU Wien, Atominstitut )
Abstract:Ion beam therapy with its advantageous capability to selectively irradiate tumors, while sparing healthy tissue, has become an increasingly used method for cancer treatment in many facilities around the globe. At the Austrian synchrotron-based ion beam therapy centre MedAustron in Wiener Neustadt, patient treatment using protons and carbon ions started by the end of 2016 and in the middle of 2019, respectively. In a dedicated non-clinical irradiation room, protons in the energy range from 62.4 MeV to 252.7 MeV and carbon ions from 120.0 MeV / nucleon to 402.8 MeV / nucleon are available for research purposes. Additionally, the energy range for protons has been extended up to 800 MeV exclusively for non-clinical research, making MedAustron an outstanding facility for experimental physics in this energy range. In this talk the characteristics of the facility will be introduced in general a
Date: Tue, 22.10.2019
Time: 16:00
Location:TU Wien, Institut für Angewandte Physik, E134 1040 Wien, Wiedner Hauptstraße 8-10 Yellow Tower „B“, 5th floor, SEM.R. DB gelb 05 B
Contact:Dr. Martin Müller

Precision in effective field theory studies for top quark and Higgs physics
Speaker:Eleni Vryounidou (CERN)
Abstract:im Rahmen des Teilchenphysikseminars
Date: Tue, 22.10.2019
Time: 16:15
Duration: 60 min
Location:Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock
Contact:A. Hoang, S. Plätzer

Phase transitions and molecular timing in T cell signaling
Speaker:Jay T. Groves (Department of Chemistry University of California, Berkeley)
Abstract:Activation of T cell receptors (TCR) by agonist peptide major histocompatibility complex (pMHC) molecules is the front line of the adaptive immune response. T cells discriminate among different pMHC based on molecular binding dwell time between pMHC and TCR, and this discrimination is widely considered to utilize a kinetic proofreading mechanism. After TCR activation, activated ZAP70 kinase at the TCR phosphorylates the scaffold molecule, LAT. It has recently been realized that LAT undergoes a protein condensation phase transition on the membrane surface, in a phosphorylation dependent manner. In this talk I will focus on the mechanism of LAT condensation and possible roles for this phase transition in the context of T cell signaling.
Date: Tue, 22.10.2019
Time: 17:00
Location:TU Wien, Institut für Angewandte Physik, E134 1040 Wien, Wiedner Hauptstraße 8-10 Yellow Tower „B“, 5th floor, SEM.R. DB gelb 05 B
Contact:Univ.Prof. Dr. Gerhard Schütz

Quantum many-body scars, mixed phase spaces and non-universal thermalization
Speaker:Makysm Serbyn (Institute of Science and Technology Austria)
Abstract:Recent The statistical mechanics description of many-particle systems rests on the assumption of ergodicity, the ability of a system to explore all allowed configurations in the phase space. For quantum many-body systems, statistical mechanics predicts the equilibration of highly excited non-equilibrium state towards a featureless thermal state. Hence, it is highly desirable to explore possible ways to avoid ergodicity in quantum systems. Many-body localization presents one generic mechanism for a strong violation of ergodicity relying on the presence of quenched disorder. In my talk I will discuss a different mechanism of the weak ergodicity breaking relevant for the experimentally realized Rydberg-atom quantum simulator. This mechanism arises from the presence of special eigenstates in the many-body spectrum that are reminiscent of quantum scars in chaotic non-interacting systems ...
Date: Wed, 23.10.2019
Time: 14:15
Location:Seminar room FH gelb 10, Institute for Theoretical Physics – Vienna University of Technology, Wiedner Hauptstraße 8 – 10, 10th floor, B (yellow tower)
Contact:Joachim Burgdörfer