CPT

Calendar of Physics Talks Vienna

Euclidean Wormholes and Holography
Speaker:Olga Papadoulaki ( ICTP, Trieste)
Abstract:In this talk I will discuss asymptotically AdS wormhole solutions in the context of holography. I will present how to compute correlation functions of local operators as well as non local observables such as correlation functions of Wilson loops on the distinct boundaries and I will discuss their behavior. Moreover, I will present deformations of the theory with multi-trace operators. From the computations mentioned we observe that, the dual theory is expected to factorize in the UV, and the two sectors to be coupled by a soft non-local interaction. Finally, I will present a simple effective field theory model that can model the behaviors that we observe from the gravity computations.
Date: Tue, 21.05.2019
Time: 13:45
Duration: 60 min
Location:TU Wien, Wiedner Hauptstraße 8, Yellow Area, 9th floor, Seminar Room DB 09 E23
Contact:S. Fredenhagen, D. Grumiller

Light-wave driven electron and spin dynamics
Speaker:Martin Schultze (TU Graz)
Date: Wed, 22.05.2019
Time: 15:00
Location:Seminar room FH gelb 10, Institute for Theoretical Physics – Vienna University of Technology, Wiedner Hauptstraße 8 – 10, 10th floor, B (yellow tower)
Contact:Joachim Burgdörfer

Soft excitations on horizons in any dimensions
Speaker:Daniel Grumiller (TU Wien)
Abstract:We derive generic properties of non-extremal horizons, assumed to be in equilibrium with a thermal bath, in any spacetime dimension greater than two. The physical properties of the thermal bath are modelled by the way we impose boundary conditions, and we shall describe various different well-motivated choices leading to infinite-dimensional near horizon symmetries, including BMS-like symmetries for arbitrary spin and Heisenberg-like symmetries. We prove that they generically span soft hair excitations in the sense of Hawking, Perry and Strominger.
Date: Thu, 23.05.2019
Time: 14:00
Duration: 60 min
Location:Arbeitsgruppe Gravitation, Währinger Strasse 17, Raum 218, 2. Stock, 1090 Wien
Contact:P.T. Chrusciel, D. Fajman

Supernova neutrinos: challenges and opportunities
Speaker:Alessandro Mirizzi (University of Bari)
Abstract:The detection of neutrinos from the next galactic supernova (SN) represents one of the next frontiers of low-energy neutrino astronomy. In this talk, I will review some of the lessons from such an observation where neutrinos largely play the role of astrophysical messengers, allowing to probe the SN explosion mechanism and to constrain the emission of exotic particles. I will put a particular emphasis on the flavor conversions of SN neutrinos. I will present recent results on self-induced effects, associated with neutrino-neutrino interactions in the deepest supernova regions. I will show how these nonlinear effects can lead "fast" flavor conversions near the SN core that would have a strong impact on the SN dynamics and on the observable neutrino fluxes.
Date: Thu, 23.05.2019
Time: 14:00
Duration: 60 min
Location:HEPHY Library
Contact:Josef Pradler

State of the art SM predictions for top-quark pairs: NNLO+EW+resummation
Speaker:Ben Pecjak (Durham)
Abstract:We review state-of-the-art SM calculations for differential cross sections in top-quark pair production. These include double QCD resummations of soft and small-mass logarithms, and also a matching procedure with NNLO QCD and NLO EW corrections. After reviewing the main ideas and phenomenological results, we discuss future directions in this challenging but important field.
Date: Thu, 23.05.2019
Time: 16:45
Duration: 60 min
Location:Fakultät für Physik, Kleiner Seminarraum, Boltzmanngasse 5, 5. Stock
Contact:A. Hoang, S. Plätzer, M. Procura