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Calendar of Physics Talks Vienna
| Positivity in the Sky (online) |
| Speaker: | Claudia De Rham (Imperial College London) |
| Abstract: | I will discuss the subtle interplay between low-energy effective descriptions relevant for our âeveryday experimentsâ, and their embeddings within an ultimate high energy completion, and how these notions are affected by gravity. I will then discuss low-energy scatterings including loops from the Standard Model in the presence of gravity and their imprints on the high energy Regge behaviour, highlighting the implications to other gauge fields and to the Weak Gravity Conjecture. |
| Date: | Tue, 13.01.2026 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Erwin-Schroedinger-HS, Boltzmanngasse 5, 1090 Wien, 5.Stock + online on Zoom |
| Contact: | S. Fredenhagen, M. Sperling |
| Spin @ 100: How spin was discovered 100 years ago |
| Speaker: | Peter van Nieuwenhuizen (Stony Brook University, New York) |
| Abstract: | How the Zeeman (1896) and Stark (1913) puzzles of spectra were solved by Goudsmit and Uhlenbeck’s concept of spin in 1925; and how spin found its natural place in the new quantum mechanics of Heisenberg (1925), Schrödinger (1926), Pauli (1927) and Dirac (1928).
After thirty years of utter confusion and despair, in 1925 several discoveries in rapid succession solved the problems of the “normal” and “anomalous” Zeeman effect: Pauli’s exclusion principle (January), Heisenberg’s first paper on quantum mechanics (July), Goudsmit and Uhlenbeck’s spin (October), and the first paper on quantum field theory by Born, Heisenberg and Jordan (November). In January 1926 Schrödinger published his first of six papers on quantum mechanics, still without spin, but in February the Thomas factor of 2 confirmed the necessity of spin.
We shall recount this fascinating history and explain the physics. |
| Date: | Tue, 13.01.2026 |
| Time: | 16:00 |
| Duration: | 60 min |
| Location: | TU Wien, Wiedner Hauptstr. 8-10, Lecture Hall FH HS 6, 2nd floor, green area (Buffet will be offered at 15:30) |
| Contact: | Anton Rebhan |
| Higgs mechanisms in supersymmetric quiver gauge theories |
| Speaker: | Chiara-Renata Horak (University of Vienna) |
| Abstract: | Quantum Field Theory is the cornerstone of modern physics, providing the fundamental framework to describe particle interactions, but its perturbative methods fail for strongly coupled systems. Supersymmetry, by relating bosons and fermions, enables exact cancellations of divergent quantum corrections. These supersymmetric theories possess a moduli space of vacua arising from flat directions in the scalar potential. The choice of a specific point in this space spontaneously breaks the symmetries of the theory, in a generalized version of the Higgs mechanism.
This talk will compare the key ideas of various new and already established algorithms and methods looking at the Higgs Mechanism on different branches of the moduli space of vacua in 3 dimensional N=4 supersymmetric theories. |
| Date: | Tue, 13.01.2026 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Erwin-Schroedinger-HS, Boltzmanngasse 5, 1090 Wien, 5.Stock |
| Contact: | A. Hoang, M. Procura, J. Pradler |
| Pulsed Laser Deposition: Possible Problems for the Deposition of Energy Materials |
| Speaker: | Thomas Lippert (PSI Center for Neutron and Muon Sciences, Villigen/Switzerland) |
| Abstract: | Thin film deposition by pulsed laser deposition (PLD) is on the verge or is already an established tool for industry, e.g. for X-ray mirrors and high Tc superconducting tapes, but for a wider application several shortcomings must be overcome. These problems, e.g. differences in composition between targets and thin films, non-homogenous composition of the thin films, and deviation of the film thickness for substrates greater than around 1 cm2, are most likely related to the ablation plume. A detailed study of the ablation plume can therefore help to understand whether and how these problems can be overcome. We apply space-, angle-, and energy-resolved plasma mass spectrometry, space- and angle-resolved ion probe measurements, and spectral- and time-resolved plasma imaging in the same PLD chamber, that is equipped with a special designed substrate system to analyse the thin films composit |
| Date: | Wed, 14.01.2026 |
| Time: | 13:30 |
| Location: | TU Wien, Institut für Angewandte Physik, E134 1040 Wien, Wiedner HauptstraÃe 8-10 Yellow Tower 5st floor, Fachgruppenraum Physik |
| Contact: | Univ.Prof. Dr. Ulrike Diebold |
| Phonon damping in one-dimensional Bose gas |
| Speaker: | Cataldini Federica (TU Wien Atominstitut) |
| Abstract: | One-dimensional (1D) quantum fluids are often modelled by Luttinger Liquid theory. The collective excitations (phonons) are expected to propagate almost without dissipation. Thermal fluctuations and deviations from linear dispersion are predicted to introduce subtle mechanisms of damping even in the deep 1D regime. In this talk, I will present experiments in which we controllably excite phonon modes in a 1D quantum fluid and monitor their subsequent time evolution. We observe that, for weak excitations, the damping is surprisingly fast and follows a non-analytic scaling law. This behavior is in quantitative agreement with the predictions of Andreev’s self-consistent hydrodynamic theory. With our results we demonstrate that phonon–phonon scattering constitutes the dominant relaxation mechanism for low-momentum, near-equilibrium excitations in 1D quantum fluids. |
| Date: | Wed, 14.01.2026 |
| Time: | 16:15 |
| Duration: | 45 min |
| Location: | Helmut Rauch Hörsaal ATI |
| Contact: | Maximilian Prüfer |
| sw1+infinity asymptotic symmetries: Carrollian & Celestial lessons |
| Speaker: | Nicolas Cresto (Perimeter Institute) |
| Abstract: | I'll give an overview of the current understanding of asymptotic higher spin symmetries (an infinite dimensional graded extension of GBMS in General Relativity) from a Noetherian perspective, with an emphasis on their algebraic structure and the complementary interplay between celestial and Carrollian viewpoints. |
| Date: | Thu, 15.01.2026 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | DA08E10, Green tower, 8th floor, Wiedner Hauptstrasse 8-10 |
| Contact: | Ankit Aggarwal, Daniel Grumiller |
| Phase transitions of static phases and time crystals in an atom cavity system |
| Speaker: | Andreas Hemmerich (Universitaet Hamburg) |
| Abstract: | Discrete (DTCs) and continuous (CTCs) time crystals are dynamical many-body states, showing robust self-sustained oscillations, emerging via spontaneous breaking of discrete or continuous time translation symmetry, respectively. DTCs are periodically driven systems that oscillate with a subharmonic of the drive, while CTCs are driven continuously and oscillate with a system inherent frequency. I will show experimental realizations of continuous and discrete time crystals in Bose-Einstein condensates of rubidium atoms strongly coupled to a high finesse optical cavity. I will discuss how these dynamical many-body phases are connected via a subharmonic injection locking process. Finally, I will present evidence that, similarly as known for 2nd order phase transitions between static phases, Kibble Zurek physics entailing power law behavior and universality can also be found for transitions b |
| Date: | Fri, 16.01.2026 |
| Time: | 10:00 |
| Duration: | 45 min |
| Location: | Helmut Rauch Hörsaal ATI |
| Contact: | Jörg Schmiedmayer |
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