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Calendar of Physics Talks Vienna
| Geometric actions and flat space holography |
| Speaker: | Max Riegler (Harvard University) |
| Abstract: | In this talk I will talk about recent progress regarding flat space holography in three spacetime dimensions.
I will argue that a Hamiltonian reduction of the Einstein-Hilbert action with Bondi-van der Burg-Metzner-Sachs (BMS) boundary conditions to future (past) null infinity yields a boundary action that is equivalent to the geometric action on BMS_3 coadjoint orbits.
This boundary action can then be used to calculate a variety of physically interesting quantities such as the one-loop torus partition function, BMS blocks or (quantum corrections of) entanglement entropy.
A particular focus will be put on the computation of entanglement entropy, quantum corrections thereof and possible consequences for a theory of quantum gravity in 3D asymptotically flat spacetimes.
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| Date: | Tue, 07.01.2020 |
| Time: | 13:45 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | S. Fredenhagen, D. Grumiller |
| Discovering New Physics with Flavour |
| Speaker: | Andreas Crivellin (PSI Villingen) |
| Abstract: | In the last years very intriguing hints for New Physics (NP) in the flavour sector have
been accumulated. In particular, deviations from the Standard Model predictions in
semi-leptonic B decays were discovered,pointing strongly towards the violating of
lepton flavour universality (LFU). These hints for NP could be related to the long
standing discrepancy in the anomalous magnetic moment of the muon which also
measures LFU violation. After reviewing the current experimental und theoretical
ituation, I will discuss possible NP models which can explain the anomalies. As it turns out, leptoquarks are prime candidates for such an explanation und I will present some interesting UV completions, including one based on the famous Pati-Salam gauge group.
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| Date: | Tue, 07.01.2020 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | A. Hoang, S. Plätzer, M. Procura |
| Relating non-relativistic strings |
| Speaker: | Gerben Oling (Niels Bohr Institute) |
| Abstract: | I will discuss recent and ongoing work on non-relativistic strings. Non-relativistic strings can potentially provide simpler theories of quantum gravity than relativistic ones, but constructing consistent non-relativistic string theories from scratch can be difficult and/or confusing. Instead, I will discuss two possible ways to obtain non-relativistic strings from relativistic ones, either from an expansion or from a null T-duality, and I will show how the resulting theories are related. Both appear to lead to consistent quantum theories with a gravitational low-energy effective interpretation. Additionally, further limits allow us to relate bulk strings to certain solvable decoupling limits of N=4 and I will argue how this relation can lead to a more direct map between boundary spin chains and bulk strings in particular subsectors of AdS/CFT. |
| Date: | Thu, 09.01.2020 |
| Time: | 16:00 |
| Duration: | 60 min |
| Location: | TU Wien, Wiedner Hauptstraße 10, Yellow Area, Seminar Room |
| Contact: | D. Grumiller, C. Zwikel |
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