CPT

Calendar of Physics Talks Vienna

Flat Space Holography in 3D
Speaker:Max Riegler (TU Wien)
Abstract:The holographic principle provides a very powerful relation between quantum field theories and theories of quantum gravity. While its most famous avatar, the anti-de Sitter/conformal field theory (AdS/CFT) correspondence, has been extensively studied during the past 25 years, extensions of holography to quantum gravity in de-Sitter or flat space are still under active development. In this talk, I will introduce the main ideas and concepts used to establish holography for asymptotically flat spacetimes in three spacetime dimensions. A particular focus will be on the basic concepts of the dual Bondi-Metzner-van der Burg-Sachs invariant quantum field theories (possibly with additional u(1) charges) and how to set up a holographic dictionary involving these quantum field theories and asymptotically flat spacetimes.
Date: Tue, 18.10.2022
Time: 14:00
Duration: 60 min
Location:Erwin-Schrödinger-Hörsaal, University of Vienna, Boltzmanngasse 5, 5th floor, Room Nr. 3500
Contact:S. Fredenhagen, D. Grumiller, E. Battista, R. Ruzziconi

QED at NNLO and beyond for precision experiments
Speaker:Yannick Ulrich (Durham University)
Abstract:Low-energy experiments allow for some of the most precise measurements in particle physics, such as g-2. To make the most of these experiments, theory needs to match the experimental precision. Over the last decade, this meant that even in QED next-to-next-to-leading order calculations (or even more in some cases) became necessary. I will discuss some of the challenges faced when dealing with QED corrections and discuss some possible solutions that we have implemented in McMule (Monte Carlo for MUons and other LEptons). McMule is a framework that we have developed to obtain NNLO predictions for a number of processes, such as $e\mu \to e\mu$, $ee \to ee$ and $\mu \to e\nu\bar\nu$.
Date: Tue, 18.10.2022
Time: 16:15
Duration: 60 min
Location:Erwin-Schrödinger-HS, Fakultät für Physik, Boltzmanngasse 5, 5. Stock sowie ZOOM https://univienna.zoom.us/j/93427906843?pwd=YjhSejdUVW16QjVQYUh5TVNSNFNhQT09
Contact:A. Hoang, M. Procura, A. Broggio

Black holes and ultra-compact objects in Einstein-scalar-Gauss-Bonnet theories
Speaker:Jutta Kunz (Universität Oldenburg)
Abstract:Einstein-scalar-Gauss-Bonnet theories lead to second order field equations, that feature a wide variety of interesting compact solutions. Depending on the coupling function of the scalar field to the Gauss-Bonnet term, different types of solutions are obtained. In this talk I will focus on coupling functions, that allow the black hole solutions of General Relativity to remain solutions of the field equations, but that yield in addition scalarized solutions. Besides a variety of scalarized black hole solutions I will discuss also other types of compact solutions. These may feature light rings and echoes and quality as UCOs, ultra-compact objects.
Date: Thu, 20.10.2022
Time: 15:15
Duration: 60 min
Location: via ZOOM https://univienna.zoom.us/j/6540036841?pwd=SytyVkZJZzNyRG9lMm13ejlHeHRRUT09
Contact:P. Chrusciel, D. Fajman

Hydrodynamic Attractors into the Unknown
Speaker: Michal P. Heller (Ghent University)
Abstract: Dynamical attractors offer a new perspective on thermalization processes in nuclear collisions at RHIC and LHC. In particular, the success of relativistic hydrodynamics in modeling far from equilibrium states has been attributed to the presence of hydrodynamic attractors. As interesting as it sounds, it is not known how general this finding is: till recently there existed simply no methods to study hydrodynamic attractors beyond the idealized setting of the boost-invariant dynamics without transverse expansion. In the talk, I will discuss ideas going in the direction of general hydrodynamic attractors and present what is new they reveal about the known cases. Based on 2003.07368, 2203.16549 and 2110.07621, 2112.12794.
Date: Thu, 20.10.2022
Time: 16:30
Duration: 60 min
Location:Freihaus, Sem.R. DB gelb 10
Contact:Kirill Boguslavski, Anton Rebhan, Iva Lovrekovic