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Calendar of Physics Talks Vienna
| From exceptional geometry to matrix models |
| Speaker: | Axel Kleinschmidt (MPI for Gravitational Physics) |
| Abstract: | Gravity-matter systems with non-abelian gauge symmetry can be constructed using the language of exceptional geometry and exceptional field theory.
I will first review some general aspects of this construction and then focus on the case of two-dimensional gravity where one can construct generalizations of Jackiw-Teitelboim gravity, in particular theories that are expected to be dual holographically to the M-theory matrix model. |
| Date: | Tue, 08.10.2024 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Erwin-Schroedinger-Hoersaal, 1090 Vienna, Boltzmanngasse 5, 5th floor |
| Contact: | S. Fredenhagen, M. Sperling |
| (High Frequency) Gravitational Waves: How and Where to Find Them |
| Speaker: | Sebastian Ellis (University of Geneva) |
| Abstract: | In the same way that we have learned about the universe by observing it across the full electromagnetic spectrum, we expect to learn as much or more by attempting to observe the universe across the fullgravitational spectrum. This has resulted in many exciting ideas for how to measure the high-frequency part of the gravitational spectrum. In this talk, we will discuss the basics of gravitational waves and their detection at the standard quantum limit. A corollary of this basic discussion will be a heuristic limit on our ability to detect cosmogenic gravitational waves at high frequencies with existing and near-future technology. |
| Date: | Tue, 08.10.2024 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Erwin-Schroedinger-Hoersaal, Boltzmanngasse 5, 5. Stock |
| Contact: | J. Pradler |
| Dynamics Non-linear media in weakly curved spacetime: optical solitons and probe pulses for gravimetry |
| Speaker: | Dennis Raetzel (ZARM, Bremen) |
| Abstract: | That light propagating in a gravitational field gets frequency-shifted is one of the basic consequences of any metric theory of gravity rooted in the equivalence principle. At the same time, also a time dependent material's refractive index can frequency-shift light propagating in it. The mathematical analogy between the two effects is such that the latter has been used to study the optical analogue of a black-hole spacetime. In the work that I will present [1], we combine these two effects by showing that light propagation in non-linear media in the presence of a moving refractive index perturbation can lead to a gravity-dependent blueshift. We find that the predicted blueshift surpasses the gravitational redshift even if the medium is considered to be perfectly stiff. [...] |
| Date: | Wed, 09.10.2024 |
| Time: | 14:15 |
| Duration: | 60 min |
| Location: | Seminarraum A, Waehringer Strasse 17, 2nd Floor |
| Contact: | Piotr T. Chrusciel, David Fajman |
| Characterising transport in a quantum gas by measuring Drude weights |
| Speaker: | Philipp Schüttelkopf (TU Wien, Atominstitut) |
| Abstract: | superconductors. A fundamental parameter in this regard is the Drude weight, which quantify the ballistic transport of charge carriers. In this work, we measure the Drude weights of an ultracold gas of interacting bosonic atoms confined to one dimension, characterising the induced atomic and energy currents in response to perturbations with an external potential. We induce currents through two distinct experimental protocols; by applying a constant force to the gas, and by joining two subsystems prepared in different equilibrium states. By virtue of integrability, dynamics of the system is governed by ballistically propagating, long-lived quasi-particle excitations, whereby Drude weights almost fully characterise large-scale transport. Indeed, our results align with predictions from a recently developed hydrodynamic theory, demonstrating almost fully dissipationless transport, even at fi |
| Date: | Wed, 09.10.2024 |
| Time: | 16:15 |
| Duration: | 45 min |
| Location: | Helmut Rauch Hörsaal ATI |
| Contact: | Maximilian Prüfer |
| Designing Novel Metasurfaces for Quantum-Enabled Positioning, Navigation, and Timing in Cold Atom Systems |
| Speaker: | Adam Lafferty (University of Glasgow) |
| Abstract: | Metamaterials are an emerging field of research, they are being increasingly integrated into a wide range of modern technologies. The remarkable flexibility of these nano fabricated structures makes them an ideal candidate for advancing the next generation of quantum technologies. This seminar will explore the design of novel metamaterials through simulation, with a focus on their application in photonic integrated chip-scale cold atom clocks. |
| Date: | Thu, 10.10.2024 |
| Time: | 11:00 |
| Duration: | 45 min |
| Location: | Seminaroom ZE 01-1, Atominstitut, TU Wien |
| Contact: | Sarah Bayer-Skoff |
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