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Calendar of Physics Talks Vienna
| Exploring the limits of no-backward-in-time signalling |
| Speaker: | Sandu Popescu (CoQuS) |
| Abstract: | One of the most routine observations that we make about our world is that we cannot signal backwards in time. So ubiquitous is this understanding that it is often taken as one of the basic laws of Nature. At first glance, this remark seems straightforward. However, as I will
show, in probabilistic theories such as quantum mechanics, the consequences of such an assertion are far more involved. In fact, we will see that there is a surprising amount of liberty: some theories even allow the future to affect the past, nevertheless without signalling backwards in time.
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| Date: | Mon, 16.12.2019 |
| Time: | 16:30 |
| Duration: | 120 min |
| Location: | Universität Wien, Lise Meitner-Hörsaal, Strudelhofgasse 4, 1090 Wien |
| Contact: | Susanne Ninaus-Meznik |
| Erwin Schrödinger Lecture: Wave localization and its landscape |
| Speaker: | Douglas N. Arnold (University of Minnesota) |
| Abstract: | The puzzling phenonenon of wave localization refers to unexpected confinement of waves triggered by disorder in the propagating media. Localization arises in many physical and mathematical systems and has many important implications and applications. A particularly important case is the Schrödinger equation of quantum mechanics, for which the localization behavior is crucial to the electrical properties of materials. Mathematically it is tied to exponential decay of eigenfunctions of operators instead of their expected extension throughout the domain. Although localization has been studied by physicists and mathematicians for the better part of a century, many aspects remain mysterious. In particular, the sort of deterministic quantitative results needed to predict, control, and exploit localization have remained elusive. |
| Date: | Mon, 16.12.2019 |
| Time: | 17:00 |
| Duration: | 60 min |
| Location: | Erwin Schrödinger Institute, Boltzmann Lecture Hall, Boltzmanngasse 9/2, 1090 Wien |
| Contact: | ESI, secr@esi.ac.at |
| A YM-like theory with infinite many fields |
| Speaker: | Loriano Bonora (SISSA, Trieste) |
| Abstract: | I will talk about the progress we have made in defining a massless field theory on a flat background with infinite many fields. It is a YM-like theory which includes also gravity, as well as tower of tensors with increasing spin. It has been derived inspired by the worldline quantization. It has a large HS gauge symmetry which includes also diffeomorphisms. I will explain its main properties and then I will show how to perturbatively quantize it. I will show as well how to define physical amplitudes and, in particular, that its is free of ghosts. It has a hidden symmetry, gauge-fixed in the initial formulation, which can be unfolded at the price of introducing nonlocalities, but I will argue that such nonlocalities are a gauge artifact. I will compare our results with the existing no-go theorems about massless HS theories in flat background. |
| Date: | Tue, 17.12.2019 |
| Time: | 13:45 |
| Duration: | 60 min |
| Location: | TU Wien, Wiedner Hauptstraße 8, Red Area, 7th floor, Seminar Room DC07 A15 |
| Contact: | S. Fredenhagen, D. Grumiller |
| Single-molecule electroluminiscence of phthalocyanine dyes |
| Speaker: | Martin Švec (Institute of Physics, Czech Academy of Sciences, Prague) |
| Abstract: | Recent development of tip-enhanced light spectroscopy reached resolution of single molecules and opened a
new channel of information in addition to the versatile toolbox of methods available to scanning probe
microscopy instrumentation working in ultrahigh vacuum and cryogenic conditions. [1] We use this opportunity
to implement single-molecule electroluminescence methodology in a combined STM/AFM and apply it in a study
of phthalocyanine derivatives and to address fundamental aspects of high-resolution photon imaging far beyond
the Abbe's limit. The usability of functionalized tips for both AFM and electroluminescence imaging of single
molecules is proven by a comparative approach; metal and CO-functionalized tips are used to obtain maps of
atomic-force related signal and excitonic spectra over a ZnPc molecule, as a function of the polarity of the
applied bias and workfunction of the su |
| Date: | Tue, 17.12.2019 |
| 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: | Univ.Prof. Dr. Ulrike Diebold |
| Dynamics of holographic phase transitions |
| Speaker: | Maximilian Attems (Santiago de Compostela University, Spain) |
| Abstract: | In this talk I will first give some overview on the current status
of the critical point search at the Relativistic Heavy Ion Collider,
in particular focusing on the hydrodynamical description. In order to
study the general dynamics of a strongly coupled system I will introduce
a holographic non-conformal model with a first order phase transition.
Its spinodal instability corresponds on the gravity side to a
Gregory-Laflamme type of instability, which settles to a preferred
final solutions. In the final part, I will show how, in contrast to
the failure of the Mueller-Isreal description of the instability, to
surprisingly well-describe such a system by hydrodynamical relations. |
| Date: | Thu, 19.12.2019 |
| Time: | 16:00 |
| Duration: | 60 min |
| Location: | Seminar room FH gelb 10, Institute for Theoretical Physics – Vienna University of Technology, Wiedner Hauptstraße 8 – 10, 10th floor, B (yellow tower) |
| Contact: | A. Rebhan, K. Boguslavski |
| Molecular membrane dynamics – a super-resolution microscopy approach |
| Speaker: | Christian Eggeling (Institute of Applied Optics and Biophysics, Friedrich-Schiller University Jena & Leibniz Institute of Photonic Technologies, Jena, Germany MRC Human Immunology Unit, University of Oxford, UK) |
| Abstract: | Molecular interactions are key in cellular signaling. They are often ruled or rendered by the mobility of the involved molecules. We present different tools that are able to determine such mobility and potentially extract interaction dynamics. Specifically, the direct and non-invasive observation of the interactions in the living cell is often impeded by principle limitations of conventional far-field optical microscopes, for example with respect to limited spatio-temporal resolution. We depict how novel details of molecular membrane dynamics can be obtained by using advanced microscopy approaches such as the combination of super-resolution STED microscopy with fluorescence correlation spectroscopy (STED-FCS). We highlight how STED-FCS can reveal novel aspects of membrane bioactivity such as of the existence and function of potential lipid rafts. |
| Date: | Fri, 20.12.2019 |
| Time: | 13:00 |
| 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 |
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