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Calendar of Physics Talks Vienna
| Measuring general relativistic effects by means of ring laser gyroscopes |
| Speaker: | Francesco GIOVINETTI (Università degli Studi di Napoli, Federico II) |
| Abstract: | From Ehrenfest’s paradox to Mach’s principle, the history of General Relativity is closely linked to the concept of rotation. However, this notion is sometimes a source of confusion and misconceptions, often caused by a lack of standardization in the language used in the scientific literature.
In this talk, we will review two non-equivalent definitions of rotation (local and “absolute” rotations) in the context of General Relativity, with particular attention to their operative definitions. After addressing the link between these two concepts and their connection to gravitation, we will provide an overview of the GINGER (Gyroscopes in General Relativity) experiment, whose main goal is to measure the Lense-Thirring effect generated by Earth's rotation using a system of ring laser gyroscopes. |
| Date: | Mon, 24.11.2025 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Seminarraum A, Währinger Straße 17, 1090 Vienna, 2nd floor |
| Contact: | D. Fajman |
| S-duality, Black Holes and Integrability |
| Speaker: | Andrea ZANETTI (University of Milan) |
| Abstract: | The study of supersymmetric partition functions plays a central role in the holographic evaluation of the Black Hole(BH) entropy via the AdS/CFT correspondence. In this talk I will discuss recent results on the study of the superconformal index for an infinite class of four dimensional N=2 necklace models. The superconformal index admits an exact evaluation in terms of solution to a set of transcendental equations, known as Bethe Ansatz equations. It has been argued in the literature in the first case of the class, namely, N=4 SU(N) super Yang-Mills (SYM), how an intriguing connection between such solutions and the vacua of of certain Elliptic Calogero-Moser systems emerges. Such contributions to the superconformal index seem to organize according to orbits of the underlying S-duality group of the theory. In this talk I will shed some light into this direction... |
| Date: | Tue, 25.11.2025 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Erwin-Schroedinger-Lecture Hall, 1090 Vienna, Boltzmanngasse 5, 5th floor |
| Contact: | S. Fredenhagen, M. Sperling |
| Laser-Induced Surface Texturing and Functionalization for Antibacterial Applications |
| Speaker: | Albena Daskalova (Institute of Electronics, Bulgarian Academy of Sciences, Sofia) |
| Abstract: | Ultra-short femtosecond (fs) lasers have emerged as a powerful tool for the fabrication of micro- and nano-patterned surfaces, offering exceptional precision and minimal thermal impact on materials. To address the challenge of bacterial contamination on frequently touched surfaces, femtosecond laser processing provides a promising, non-destructive approach for creating hierarchical micro/nano-structures. By inducing controlled groove-like textures on metals and polymers, it is possible to tailor surface roughness characteristics that influence bacterial adhesion behavior. Variations in surface morphology—particularly in terms of feature height and spacing—play a crucial role in determining bactericidal efficiency. Thus, laser-induced surface texturing offers a purely geometrical route to modulate bacterial attachment without the need for chemical treatment or coatings. |
| Date: | Tue, 25.11.2025 |
| 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. Laura Mears |
| Heavy particle EFT methods for precision beta decays |
| Speaker: | Ryan PLESTID (Ohio State University, CERN) |
| Abstract: | A tension in the unitarity of the first-row of the CKM matrix has emerged in recent years. This "Cabibbo anomaly" has motivated a renewed scrutiny of the QED corrections applied to low-energy precision beta decays.
In this talk I will explain how this problem can be formalized in effective field theory, ultimately descending to a heavy-quark-like effective theory of point-like nuclei. I will outline recent progress on the control of high order QED corrections in this point-like theory, including an understanding of the all-orders structure for the Z-enhanced Coulomb-corrections, and comment on implications for the extraction of |V_{ud}| and the interpretation of beta-decay experiments. |
| Date: | Tue, 25.11.2025 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Erwin-Schroedinger-Lecture Hall, 1090 Vienna, Boltzmanngasse 5, 5th floor |
| Contact: | A. Hoang, J. Pradler, M. Procura |
| What can we learn (or not) about quantum gravity from experiments? |
| Speaker: | Markus ASPELMEYER (University of Vienna) |
| Abstract: | Already in 1916, in his first paper on gravitational waves, Einstein emphasized the necessity to treat gravitational waves quantum theoretically and concluded that “quantum theory must modify not only Maxwellian electrodynamics but also the new theory of gravitation”. However, at that time, simple estimates indicated that it would be impossible to ever experimentally observe any phenomena that meaningfully involved quantum dynamics of the gravitational field. Thus, the hope of testing ideas about quantum gravity with experiments languished for nearly a century.
In the past few decades, however, the notion that we might be able to gain experimental access to quantum gravitational phenomena has resurfaced in a wide variety of contexts, from cosmology to tabletop scales, the latter being driven mostly by the recent advent of ultra-sensitive quantum control and detection in mesoscopic... |
| Date: | Wed, 26.11.2025 |
| Time: | 14:15 |
| Duration: | 60 min |
| Location: | VERA Seminar Room (Viktor-Franz-Hess Lecture Hall), Waehringer Straße 17, 1090 Vienna, Hoftrakt, 1st floor |
| Contact: | D. Fajman |
| Stability of matter: The 50th anniversary of the Lieb--Thirring proof |
| Speaker: | Rupert Frank (LMU Munich) |
| Abstract: | In September 1975, Lieb and Thirring published their foundational paper `Bound for the kinetic energy of fermions which proves the stability of matter'. We give a non-technical introduction to this problem, explain the insights of Lieb and Thirring, as well as the ramifications of their work. |
| Date: | Wed, 26.11.2025 |
| Time: | 16:00 |
| Duration: | 60 min |
| Location: | Boltzmann Lecture Hall, Erwin Schrödinger Institut, Boltzmanngasse 9, 1090 Wien |
| Contact: | Erwin Schrödinger Institut |
| Non-Hermitian dynamics of optically coupled nanoparticles |
| Speaker: | Egyed Livia (TU Wien Atominstitut) |
| Abstract: | Optically levitated nanoparticles are a promising system for studying many body (quantum) interactions due to their strong environmental isolation as well as the ability to obtain quantum control over them. Our platform of programmable arrays of levitated nanoparticles with highly tunable interactions provide access to a wide range of system parameters, enabling us to adjust the coupling between the particles from fully reciprocal to uni-directional and up until fully anti-reciprocal by modifying their trapping fields. In case of anti-reciprocal coupling, we observe signatures of non-Hermitian dynamics, exceptional points and PT symmetry breaking. For coupling rates g>γ/2, the system exhibits a Hopf-bifurcation into a mechanical lasing phase, where the particles oscillate along stable limit-cycle trajectories. |
| Date: | Wed, 26.11.2025 |
| Time: | 16:45 |
| Duration: | 45 min |
| Location: | Helmut Rauch Hörsaal ATI |
| Contact: | Maximilian Prüfer |
| Supersolids in Magnetic Gases: From Roton Softening to Quantum Vortices |
| Speaker: | Francesca Ferlaino (U of Innsbruck) |
| Abstract: | The exploration of low-temperature physics has captivated scientists for decades, unveiling groundbreaking phenomena such as superfluidity across a variety of states of matter, including solids, liquids, gases, and even light. A central focus of this field has been the emergence of superfluid order in spatially homogeneous systems. However, what occurs when superfluidity emerges alongside periodic density modulations? Can a supersolid state exists, where localization inherent to periodic structures coexist with superfluidity? Is it possible for a solid to exhibit superfluid behavior, or for a superfluid to display crystalline order?
This talk will delve into the experimental realization of supersolidity in magnetic quantum gases, enabled by the momentum-dependent, long-range, and anisotropic dipole-dipole interactions. |
| Date: | Thu, 27.11.2025 |
| Time: | 16:00 |
| Duration: | 60 min |
| Location: | Boltzmann Lecture Hall, Erwin Schrödinger Institut, Boltzmanngasse 9, 1090 Wien |
| Contact: | Erwin Schrödinger Institut |
| Cold atoms: A wonderful platform for quantum physics |
| Speaker: | Hanns-Christoph Nägerl (Universität Innsbruck) |
| Abstract: | Since the formation of atomic Bose-Einstein condensates (BEC) nearly 30 years ago, systems of cold atoms have developed into a versatile playground for the investigation into quantum many-body physics, with the promise to shed light onto dynamical processes in the spirit of quantum simulation efforts. With exquisite parameter control and a broad range of detection methods, a multitude of phenomena, ranging from superfluidity and quantum phase transitions to supersolidity and quantum transport, can be probed with high precision. I will give a broad introduction to the field of cold atoms and its techniques, and then turn to a selected set of experiments from my group that address various dynamical quantum many-body phenomena such as dynamical localization in 1D [1] and, surprisingly, also in 3D [2], and the breaking thereof, anyonization of bosons [3], and fractional Fermi seas [4]. |
| Date: | Fri, 28.11.2025 |
| Time: | 10:00 |
| Duration: | 45 min |
| Location: | Helmut Rauch Hörsaal ATI |
| Contact: | Tim Langen |
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