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Calendar of Physics Talks Vienna
| Quantum Null Energy Condition – Analytic, Perturbative and Numerical Results |
| Speaker: | Philipp Stanzer (TU Wien) |
| Abstract: | The quantum null energy condition (QNEC) is the only known local energy condition
which holds in any quantum field theory in more than two dimensions (given some
assumptions like unitarity). The QNEC relates the null-projection of the energy momentum tensor to the second variation of the entanglement entropy with respect
to a deformation of the entangling region along the same null direction.
After studying QNEC in four dimensional holographic conformal field theories, we
consider similar setups in two spacetime dimensions, where the QNEC takes a sharper
form. We are especially interested in the saturation behavior of the QNEC inequality
and its relation to matter in the bulk of the dual theory as well as in the leading
corrections to the supergravity approximation from quantum backreactions for
finite Newton coupling.
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| Date: | Tue, 15.01.2019 |
| Time: | 13:45 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | S. Fredenhagen, D. Grumiller |
| Infrared analysis for perturbative amplitudes |
| Speaker: | George F. Sterman (SUNY, Stony Brook) |
| Abstract: | 3. Vorlesung im Rahmen der Schrödinger-Gastprofessur:
I'll review how infrared divergences arise in perturbative amplitudes with massless particles
For fixed-angle and forward scattering, introducing Landau equations, Coleman-Norton
Physical pictures and power counting as tools. In gauge theories, this analysis leads to
factorized expressions, closely related to effective theory descriptions of the amplitudes.
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| Date: | Tue, 15.01.2019 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | A. Hoang, H. Neufeld |
| Strong Cosmic Censorship and Quasinormal Modes |
| Speaker: | Joao Costa (ISCTE Lisboa, Portugal) |
| Abstract: | I will present some recent results concerning the Strong Cosmic Censorship Conjecture (SCCC) in the presence of a positive cosmological constant. I will start by reviewing some of the progress made in the context of the Einstein-Maxwell-scalar field system in spherical symmetry and the linear wave equation in the black hole interior of Reissner-Nordström de Sitter. These results show that the validity of the SCCC hinges on the precise decay rates of perturbations along the event horizon which are known to be determined by the black hole´s quasinormal spectrum. I will also discuss recent numerical computations of quasinormal modes that suggest the failure of th SCCC in
a near extremal regime of charged de Sitter black holes.
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| Date: | Thu, 17.01.2019 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Arbeitsgruppe Gravitation, Währinger Strasse 17, Raum 218, 2. Stock, 1090 Wien |
| Contact: | P.T. Chrusciel, D. Fajman |
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