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Calendar of Physics Talks Vienna
| The Λ-BMS Charge Algebra in n dimensions |
| Speaker: | Adrien Fiorucci (Université Libre de Bruxelles (ULB)) |
| Abstract: | The aim of my talk is to discuss brand-new results about the phase space of Einstein’s gravity in arbitrary dimensions with non-vanishing cosmological constant Λ. I will start by reviewing the solution space of asymptotically locally (A)dS spacetimes in the Starobinsky/Fefferman-Graham gauge and the renormalization of the presymplectic current needed when the boundary structure is allowed to fluctuate. Next, I will discuss the gravitational charge algebra for generic Al(A)dSnspacetimes, without assuming any further boundary condition than the minimal falloffs allowing for conformal compactification. Then I will introduce the Λ-BMSnalgebroid arising from some boundary gauge fixing and reducing to the Generalized BMSnalgebra in the flat limit Λ→0. [...] - see the rest on https://www.univie.ac.at/jointtheoryseminar/ |
| Date: | Tue, 10.11.2020 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | https://moodle.univie.ac.at/mod/bigbluebuttonbn/guestlink.php?gid=x8o6ILSKJuC9 |
| Contact: | Céline Zwikel |
| Dilaton chiral perturbation theory |
| Speaker: | Maarten Golterman (San Francisco State University) |
| Abstract: | Recent simulations suggest the existence of a very light singlet
scalar in QCD-like theories that may be lying just outside the
conformal window. Assuming that the lightness of this scalar can
be explained by an approximate dilatation symmetry, we develop
an effective field theory framework for both the pions and this light
scalar, the "dilatonic meson" or dilaton. We argue that a power
counting exists that puts this effective field theory on a systematic
footing. We compare the predictions of the effective theory with
recent lattice data. |
| Date: | Tue, 10.11.2020 |
| Time: | 16:00 |
| Duration: | 60 min |
| Location: | ZOOM |
| Contact: | A. Hoang, M. Procura, S. Plätzer |
| Measurements, entropy and the arrow of time |
| Speaker: | Markus Huber (Universität Wien) |
| Abstract: | As most of the relevant physical processes we experience are very well described by time-reversal symmetric theories, one of the most sought after questions in physics concerns the origin of an arrow of time. Starting from fundamental quantum physical considerations, I will discuss the two most prominent processes that break time-reversal symmetry-the second law of thermodynamics and the projection postulate- and show that they are in a sense very closely related. With this in mind, I will present our latest research on identifying the fundamental operating principles of timekeeping devices, i.e. our exploration of how clocks rely on the increase of entropy and how the amount of dissipated entropy determines the ultimate limitations of clock quality. |
| Date: | Fri, 13.11.2020 |
| Time: | 10:00 |
| Duration: | 45 min |
| Location: | on-line |
| Contact: | Jörg Schmiedmayer |
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