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Calendar of Physics Talks Vienna
| Self-organised localisation |
| Speaker: | Gian Giudice (CERN, Schweiz) |
| Abstract: | 2nd talk - Erwin-Schroedinger visiting scientist:
The phenomenon of self-organised localisation is presented. When the fundamental parameters of a theory are functions of a scalar field subject to large fluctuations during inflation, quantum phase transitions can act as dynamical attractors.
As a result, the theory parameters are probabilistically localised around the critical value and the Universe finds itself at the edge of a phase transition. Examples will be given in which self-organised localisation accounts for the observed near-criticality of the Higgs self-coupling, the naturalness of the Higgs mass, or the smallness of the cosmological constant. |
| Date: | Tue, 13.06.2023 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Fakultaet fuer Physik, Erwin Schroedinger-HS, Boltzmanngasse 5, 5. Stock |
| Contact: | A. Hoang, H. Neufeld, M. Procura |
| Ions and water at aqueous interfaces |
| Speaker: | Roland Netz (Freie Universität Berlin, Theoretical Physics, Berlin/Germany) |
| Abstract: | The air-water interface displays complex static and dynamics properties, which become relevant when describing interfacial ion effects. Different definitions of the electrostatic potential, each relevant for distinct experimental scenarios, lead to widely varying surface potential magnitudes and even different signs. Based on quantum-chemical density-functional molecular dynamics simulations, a few different surface potentials are evaluated and compared. The spatially averaged surface potential, accessible to electron holography, is dominated by the trace of the water molecular quadrupole moment and amounts to more than + 4 Volt inside the water phase, very different from results obtained with force-field water models. The surface potential inside a cavity is much smaller, less than 200 mVolt in magnitude. This is the electrochemical surface potential relevant for ion transfer reaction |
| Date: | Tue, 13.06.2023 |
| Time: | 16:30 |
| Location: | TU Wien, Institut für Angewandte Physik, E134 1040 Wien, Wiedner HauptstraÃÂe 8-10 Yellow Tower âÂÂBâÂÂ, 5th floor, SEM.R. DB gelb 05 B |
| Contact: | Univ.Prof. Dr. Markus Valtiner |
| Towards correlated momentum measurements in coincident electron-photon pairs |
| Speaker: | Alexander Preimesberger (TU Wien, Atominstitut) |
| Abstract: | In recent years temporal correlations in electron-photon pairs have been employed to resolve excitation lifetimes [1], suppress background in core loss EELS [2] and suppress noise in optical mode imaging [3]. In this talk, I present our progress towards measuring momentum correlations in coincident electron-photon pairs.
By collecting coherently emitted photons [4] from a thin slab of mono-crystalline silicon and correlating them in time with the electron detection signal from a time-resolved direct detection camera (Timepix3), we plan to measure the momentum transfer of a single photon on the electron. This will allow us to infer the electron energy loss of a single electron by filtering the wavelength of the associated photon. Thin crystalline silicon slabs are a very well-studied system, it has been shown that electron deflection due to the Cherenkov effect can be resolved in angle- |
| Date: | Wed, 14.06.2023 |
| Time: | 16:15 |
| Duration: | 45 min |
| Location: | Helmut Rauch Hörsaal ATI |
| Contact: | Maximilian Prüfer |
| Jet quenching in evolving anisotropic matter |
| Speaker: | Andrey Sadofyev (Santiago de Compostela U., IGFAE) |
| Abstract: | Over the last decades, the theoretical picture of how hadronic jets interact with nuclear matter has been extended to account for the mediumâs finite longitudinal length and expansion. However, only recently a first-principle approach has been developed that allows to couple the jet evolution to the medium flow and anisotropic structure in the dilute limit. In this talk, I will show how to extend this approach to the dense regime, where the resummation of multiple in-medium scatterings is necessary. Particularly, I will consider the modifications of the single particle momentum broadening distribution and single gluon production rate in evolving matter. The resummation is performed by either computing the opacity series or starting from the all order BDMPS-Z formalism. I will also discuss the (novel) resulting modifications to jets' substructure, and briefly mention the effects of mass |
| Date: | Thu, 15.06.2023 |
| Time: | 15:00 |
| Duration: | 60 min |
| Location: | TU Wien, Freihaus, Seminar room 10th floor; Zoom: Meeting ID: 950 0240 9522, Password: please ask via e-mail |
| Contact: | Kirill Boguslavski, Iva Lovrekovic |
| Quantum reaction-diffusion systems |
| Speaker: | Igor Lesanovsky (Universität Tübingen) |
| Abstract: | Ongoing progress in the control of cold atomic gases continuously
offers new opportunities for creating and probing quantum matter.
In this talk I will discuss how these advances put us into position
to investigate the impact of quantum effects on collective behavior
and the long-time dynamics of many-body systems out of equilibrium.
I will focus mainly on two instances: the contact process [1],
which is a simple model for epidemic spreading, and lattice gases
featuring two-body annihilation [2]. In both settings the
introduction of non-classical effects, such as coherence, appears
to alter emergent dynamical behavior. This manifests in a change of
static and dynamical critical exponents, which can in principle be
probed on lattice quantum simulators with Rydberg and ground state
atoms. The particular challenge is (also for theory) that an
unambiguous identification of these signatures r |
| Date: | Fri, 16.06.2023 |
| Time: | 10:00 |
| Duration: | 45 min |
| Location: | ATI Hörsaal/https://tuwien.zoom.us/j/93672218922?pwd=dEZNQ2liVzRNNURvNmVWVE5KUWRiQT09 |
| Contact: | Jörg Schmiedmayer |
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