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Calendar of Physics Talks Vienna
| New operators and RG flows on Wilson lines in general representations |
| Speaker: | Daniele Artico (University of Parma) |
| Abstract: | Wilson lines are non-local probes of a gauge theory and define lower- dimensional quantum systems with their own local operators, OPEs and renormalisation-group flows. Their structure depends on the representation carried by the line, and understanding this dependence provides a simple setting in which to explore how the physics of defects changes as the underlying extended operator is varied. I will first review Wilson lines from the viewpoint of defect CFT, and briefly relate this perspective to the broader algebraic structure of extended operators. I will then discuss a new class of local operators that appears for Wilson lines in sufficiently general representations of the gauge group. In N=4 SYM, these operators lead to new defect deformations whose RG behaviour can be determined perturbatively. I will explain how their beta functions are tied to defect OPE data |
| Date: | Tue, 27.10.2026 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | ESI - Schroedinger lecture hall, Boltzmanngasse 9, 1090 Wien |
| Contact: | S. Fredenhagen, M. Sperling |
| Tailored PDFs for new physics searches |
| Speaker: | Elie Hammou (NIKHEF Amsterdam) |
| Abstract: | Indirect searches for new physics at the LHC increasingly rely on precision measurements in the high-energy tails of kinematic distributions, where uncertainties from Parton Distribution Functions (PDFs) are often a bottleneck. In this talk, I study the interplay between PDFs and Standard Model Effective Field Theory (SMEFT) interpretations in two key LHC sectors: Drell–Yan and top-quark production. I compare two complementary strategies for robust PDF determination for new-physics searches: (i) simultaneous fits of PDFs and SMEFT Wilson coefficients, and (ii) sequential fits based on an initial conservative PDF determination using observables that can be reliably assumed to be SM-like. Both approaches are assessed through controlled closure tests in a realistic High-Luminosity LHC scenario.I show how different fitting strategies impact PDFs determination and SMEFT constraints and pro |
| Date: | Tue, 27.10.2026 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Erwin-Schroedinger-HS, Boltzmanngasse 5, 1090 Wien, 5.Stock |
| Contact: | A. Hoang, M. Procura, J. Pradler |
| Dispersive Shock Waves in a 1D Quantum Liquid |
| Speaker: | Philipp Schüttelkopf (Atominstitut, TU Wien) |
| Abstract: | Atominstitut, TU Wien
We implement a moving boundary condition in a 1D quantum liquid to study nonlinear wave breaking and its regularization by dispersion. Programmable optical potentials allow us to compress a weakly interacting ultra-cold Bose gas trapped on an atomchip at tunable speeds of up to three times the speed of sound and we subsequently measure the quasi-in-situ density distribution to extract the shock wave edge dynamics. We resolve both leading and trailing edge velocities and observe a shock wave width that increases linearly in time, which are distinguishing features of dispersive shock waves, consistent with asymptotic predictions using Whitham's method. Quantitative agreement is found with finite temperature non-polynomial Schrödinger equation simulations, taking into account the imaging process and the finite height of the piston potential. Our results constitute a co |
| Date: | Wed, 28.10.2026 |
| Time: | 16:00 |
| Duration: | 45 min |
| Location: | Helmut Rauch Hörsaal, ATI |
| Contact: | Elena Redchenko |
| Boundaries and defects in thermal conformal field theories |
| Speaker: | Daniele Artico (University of Parma) |
| Abstract: | In this talk, I develop a framework for studying conformal field theories with boundaries and defects at finite temperature, with particular emphasis on the interplay between thermal and defect geometries. The resulting non-trivial geometry strongly constrains correlation functions. I derive the allowed one-point functions of scalar, vector, and spin-two operators for defects both wrapping and localized on the thermal circle, and obtain KMS sum rules constraining defect CFT data. I then present explicit one- and two-point functions in free theories, illustrating the analytic structures that emerge at finite temperature. I conclude by outlining how these results can be used to formulate a defect-bootstrap programme for thermal CFTs, highlighting open problems and exciting directions. |
| Date: | Thu, 29.10.2026 |
| Time: | 16:00 |
| Duration: | 60 min |
| Location: | ITP, TU Wien, Wiedner Hauptstr. 8-10, Sem.R. DB gelb 10 |
| Contact: | Paul Romatschke, Gerben Oling |
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