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Calendar of Physics Talks Vienna
| Welcome to the MaZe, a new approach for simulating adiabatic systems |
| Speaker: | Sara Bonella (CECAM, EPF Lausanne) |
| Abstract: | In several domains of physics, including first principles simulations and classical models for polarizable systems, the minimization of an energy function with respect to a set of auxiliary variables must be performed to define the dynamics of physical degrees of freedom. In this talk, a recent and effective formalism to simulate this type of systems will be discussed: the Mass-Zero (MaZe) Constrained Dynamics [1]. In MaZe the minimum condition is imposed as a constraint on the auxiliary variables treated as degrees of freedom of zero inertia driven by the physical system. The method is formulated in the Lagrangian framework, enabling the properties of the approach to emerge naturally from a fully consistent dynamical and statistical viewpoint [2].
Several examples of current uses of MaZe will be rapidly presented. |
| Date: | Tue, 07.03.2023 |
| Time: | 13:15 |
| Duration: | 60 min |
| Location: | Erwin Schrödinger Institute, Boltzmann Lecture Hall, Boltzmanngasse 9, 1090 Wien |
| Contact: | Erwin Schrödinger Institute, University of Vienna |
| Three-dimensional gravity in the BV-BFV formalism |
| Speaker: | Giovanni Canepa (University of Vienna) |
| Abstract: | In this talk I will give a brief introduction to the BV-BFV formalism for quantum field theories.
Subsequently, I will present the BV-BFV formulation of three-dimensional general relativity in
the Einstein Cartan variables and draw a connection with BF and Chern-Simons theories.
This talk is based on arXiv:1905.09333, a joint work with Michele Schiavina. |
| Date: | Tue, 07.03.2023 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | TU - Sem.R. DB gelb 03 (Freihaus, TU Wien, Wiedner Hauptstrasse 8) |
| Contact: | S. Fredenhagen, D. Grumiller, E. Battista, R. Ruzziconi |
| Phase transitions and self assembly in active matter |
| Speaker: | Ignacio Pagonabarraga (University of Barcelona) |
| Abstract: | Flocks of birds, schools of fishes, or bacterial colonies constitute examples of living systems that coordinate their motion. In all these systems their constituent elements generate motion due to energy consumption and can exchange information or react sensitively to chemical cues in order to move together or to react collectively to external signals. Artificial systems, such as nanorobots, exploit the heterogeneous compositions of their surface to displace as a result of the heterogeneous chemical processes that take place in the presence of appropriate chemical substances.
All these systems are intrinsically out of equilibrium in the absence of any external driving. Therefore, their collective properties result as a balance between their direct interactions and the indirect coupling to the medium in which they displace, and a self-consistent dynamical approach is required. |
| Date: | Tue, 07.03.2023 |
| Time: | 14:15 |
| Duration: | 60 min |
| Location: | Erwin Schrödinger Institute, Boltzmann Lecture Hall, Boltzmanngasse 9, 1090 Wien |
| Contact: | Erwin Schrödinger Institute |
| Engineering artificial cells from the bottom-up using microfluidics |
| Speaker: | Tom Robinson (Max-Planck-Institute of Colloids and Interfaces, Potsdam/Germany) |
| Abstract: | One of the aims of synthetic biology is the bottom-up construction of synthetic cells from non-living components. Building biomimetic cells and controlling each aspect of their design not only provides the opportunity to understand real cells and their origins, but also offers alternative routes to novel biotechnologies. Giant unilamellar vesicles (GUVs) are commonly used as scaffolds to construct synthetic cells owing to their compatibility with existing biological components, but traditional methods to form them are limited. Microfluidic-based approaches for GUV production show great potential for encapsulating large biomolecules required for mimicking life-like functions (Yandrapalli et al. Micromachines, 11, 285, 2020; Love et al. Angew Chemie, 59, 5950â5957, 2020). First, I will present a microfluidic platform that is able to produce surfactant-free pure lipid GUVs in a high-through |
| Date: | Tue, 07.03.2023 |
| Time: | 16:00 |
| Location: | TU Wien, Institut für Angewandte Physik, E134 1040 Wien, Wiedner HauptstraÃe 8-10 Yellow Tower âBâ, 5th floor, SEM.R. DB gelb 05 B |
| Contact: | Univ.Prof.Dr.M.Valtiner |
| Coupling Spins in Cryogenic Solids to a Superconducting Resonator |
| Speaker: | Andrew Niels Kanagin (TU Wien, Atominstitut) |
| Abstract: | Here I present a novel platform for quantum technologies, where we grow crystals of solid noble gasses (p-H2, Ne, Arâ¦) which host an ensemble of alkali impurities (Rb, Na, Csâ¦) at high densities atop a superconducting resonator. The noble gas crystal offers an inert, soft, and versatile matrix which aims to minimize the interaction between the matrix and impurity in hopes to preserve the favorable atomic properties. Additionally, these crystals offer a modular platform for a wide range of impurities to be embedded and studied. The alkali impurities have hyperfine transitions of roughly 1-10GHz, which are coupled to superconducting microwave resonators at temperatures of 50mK. Leveraging the high densities of the alkali impurities, in particular sodium in a solid neon matrix, we achieved strong coupling between the resonator and the ensemble via the collective enhancement coupling factor |
| Date: | Wed, 08.03.2023 |
| Time: | 16:15 |
| Duration: | 45 min |
| Location: | Hörsaal ATI |
| Contact: | RugWay Wu |
| Erwin Schrödinger Lecture: Our changing climate system |
| Speaker: | Georg Kaser (University of Innsbruck) |
| Abstract: | Climate change is ongoing. Both insidious changes such as sea level rise or vector migration and the increase of extreme events in their frequency as well as their intensity are evident. Extensive detrimental impacts and related costs will occur in the targeted +1.5°C World and even more so if we get to +2°C above pre-industrial levels. It is all but sure that we will be able to meet this âParis agreementâ at all. Global greenhouse gas emissions are higher than ever and they increase further. There are first indications of the onsets of several irreversible subsystem changes that may both individually or in cascades cause positive feedbacks leaving us without any further chance to counteract. There is still a small window open for action, yet it requires an immediate and deep transition of the global society. |
| Date: | Wed, 08.03.2023 |
| Time: | 17:00 |
| Duration: | 60 min |
| Location: | Erwin Schrödinger Institute, Boltzmann Lecture Hall, Boltzmanngasse 9, 1090 Wien |
| Contact: | Erwin Schrödinger Institute |
| Speaker: | Stefan Hollands (Leipzig) |
| Abstract: | The strong cosmic censorship hypothesis asserts that the inner horizons of Kerr-Newman(-deSitter) black holes are unstable against classical perturbations,
thus effectively eliminating any problems with causality and determinism associated with the regions beyond the inner horizon.
I discuss the status of this conjecture and emphasise the importance of quantum effects to avoid violations of strong cosmic censorship in the presence of a (positive) cosmological constant. |
| Date: | Thu, 09.03.2023 |
| Time: | 15:30 |
| Duration: | 60 min |
| Location: | via zoom https://univienna.zoom.us/j/6540036841?pwd=SytyVkZJZzNyRG9lMm13ejlHeHRRUT09 |
| Contact: | P. Chrusciel, D. Fajman |
| Can we prove that cosmic structures are of quantum mechanical origin? |
| Speaker: | Vincent Vennin (APC Paris) |
| Abstract: | In the early universe, quantum vacuum fluctuations are amplified and stretched to large distances, giving rise to cosmological over-densities that seed the large-scale structure of our universe. However, astronomers usually analyse the data with purely classical techniques and apparently never need to rely on the quantum formalism to understand them. So are there observational signatures of the quantum origins of primordial perturbations? If confirmed, what would we learn about quantum physics in gravitational contexts? |
| Date: | Fri, 10.03.2023 |
| Time: | 10:00 |
| Duration: | 45 min |
| Location: | ATI Hörsaal/https://tuwien.zoom.us/j/93672218922?pwd=dEZNQ2liVzRNNURvNmVWVE5KUWRiQT09 |
| Contact: | Christian Käding |
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