|
Calendar of Physics Talks Vienna
| Driving frequency comb research through the synergy of theory and experiment |
| Speaker: | Benedikt Schwarz (TU Wien) |
| Abstract: | Optical frequency combs (OFCs) play a central role in modern photonics, enabling advances in fundamental science, precision sensing, and high-resolution spectroscopy. Established approaches to generating ultrashort soliton pulses in passive media—most notably optical fibers and microresonators—provide highly stable, broadband OFCs but rely on external pump lasers and additional optical components, limiting system compactness and integration. Direct comb generation in semiconductor lasers offers a compelling alternative, promising monolithic integration and reduced complexity, yet it introduces significant challenges related to coherence, dispersion control, and nonlinear dynamics. |
| Date: | Tue, 27.01.2026 |
| Time: | 12:10 |
| Duration: | 75 min |
| Location: | TU Wien: Wiedner Hauptstr. 8-10, green area, 5th floor, seminar room DA05E10 |
| Contact: | Luciano Montecchio |
| Poincaré duality and supergravity |
| Speaker: | John Huerta (LMU Munich) |
| Abstract: | The superfield formalism is an approach to supersymmetric field theories where the fields are functions on supermanifolds. We describe the peculiar features of supermanifolds that play a role in the superfield formalism, how these peculiar features lead to a novel form of Poincaré duality with no classical analogue, and sketch some of its applications to physics.
This is joint work with Konstantin Eder and Simone Noja. |
| Date: | Tue, 27.01.2026 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Erwin-Schroedinger-HS, Boltzmanngasse 5, 1090 Wien, 5.Stock |
| Contact: | S. Fredenhagen, M. Sperling |
| Gravity is Induced from Renormalization Group Flow |
| Speaker: | Shahin Sheikh Jabbari (IPM, Tehran) |
| Abstract: | We revisit the holographic renormalization group (RG) setting in which a 4-dimensional (4d) quantum field theory at a finite cutoff corresponds to/is described by the Einstein gravity on a part of AdS5 space, cutoff at a finite radius. This holographic setting has interesting and important implications for the 4d field theory: Deformation of the field theory by a certain combination involving the square of its energy-momentum tensor can be alternatively viewed as formulating the field theory on a background with a dynamical metric. Explicitly, starting with a non-gravitating 4d field theory in the UV, flowing to the IR, quantum effects that we compute using the classical 5d Einstein gravity theory, induce an effective 4d Einstein gravity theory. In other words, we show that gravity is not a fundamental force and is an effective description of quantum effects in the IR limit. |
| Date: | Thu, 29.01.2026 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Online; Zoom broadcast in DA08E10, Green tower, 8th floor, Wiedner Hauptstrasse 8-10 |
| Contact: | Ankit Aggarwal, Daniel Grumiller |
| Optomechanical interfaces for scalable hybrid quantum networks |
| Speaker: | Simon Gröblacher (TU Delft ) |
| Abstract: | Hybrid quantum networks that interconnect distinct quantum technologies offer a promising route toward scalable quantum information processing. A central challenge in realizing such architectures is the coherent interfacing of disparate physical systems. Mechanical resonators have emerged as powerful mediators in this context, owing to their ability to couple to a widerange of quantum platforms and their highly engineerable properties. In particular, nanomechanical systems provide a versatile interface for coherently connecting otherwise incompatible qubits.
Here we present a series of experiments based on optomechanical crystals supporting gigahertz-frequency mechanical modes that can be optically addressed. We observe and characterize coherent photon–phonon interactions, enabling the storage of quantum states of light in mechanical motion as well as coherent frequency conversion betwe |
| Date: | Fri, 30.01.2026 |
| Time: | 10:00 |
| Duration: | 45 min |
| Location: | Helmut Rauch Hörsaal ATI |
| Contact: | Uros Delic |
|