Seminars

The Seminars start at 1:45pm. They are held alternately at:

  • TU Wien (TU): Getreidemarkt 9, Maschinenbaugebäude, 1st floor, Hörsaal Kleiner Schiffbau
  • University of Vienna (UV): Boltzmanngasse 5, 5th floor, Schrödinger Lecture Hall

 A list of all upcoming seminars can be found here.

Upcoming Seminars:

20-11-2018, 1:45pm at the UV: Céline Zwikel (TU Wien) will talk on „Asymptotic symmetries of three-dimensional black strings“

Abstract: In three-dimensional pure gravity, there are no asymptotically flat black holes. However, once matter is present, richer geometries appear: it is the case for the Horne-Horowitz black string and its generalisation.  During this talk, I will present the first set of consistent boundary conditions which include the black string and leads to finite, integrable and conserved charges.  The asymptotic symmetry algebra consists in a Witt algebra supplemented by three global u(1) charges.  In the last part of the talk, I will discuss the thermodynamics of these solutions and point out some peculiar features of this system.

 

 

30-11-2018, 1:30pm, small seminar room, Boltzmanngasse 5, 5th floor: Stefan Groot Nibbelink (Rotterdam University of Applied Sciences) will talk on `Tension Between a Vanishing Cosmological Constant and Non-Supersymmetric Heterotic Orbifolds'.

Abstract: We investigate under which conditions the one-loop cosmological constant vanishes for heterotic strings on non-supersymmetric toroidal orbifolds. To obtain model-independent results, we require that each orbifold sector preserves at least a single Killing spinor, but not always the same one. The existence of such Killing spinors is related to the representation theory of the point groups that underly the orbifold geometries. Going through all inequivalent (Abelian and non-Abelian) point groups of six-dimensional toroidal orbifolds shows that this is never possible: For any non-supersymmetric orbifold there is always (at least) one sector, that does not admit any Killing spinor and hence gives a non-vanishing contribution to the partition function which most likely results in a too large cosmological constant. (The underlying reason for this can be phrased as a mathematical conjecture, which was tested for a much larger class of finite groups.) This result shows that it is very challenging to obtain a tiny cosmological constant on non-supersymmetric heterotic orbifolds.

Past Seminars (2016-2018):

  • Wolfgang Wieland (Perimeter Institute for Theoretical Physics, Waterloo, Canada) on „Loop Quantum Gravity and the Continuum“ (13-11-2018)
  • Niccolò Cribiori (TU Wien) on `Linear versus Non-linear Supersymmetry' (06-11-2018)
  • Max Riegler (Université Libre de Bruxelles, Bruxelles, Belgium) on `Warped Black Holes in Lower-Spin Gravity' (30-10-2018)
  • Maulik Parikh (Arizona State University, Tempe, Arizona) on `The Three Laws of Future Light Cone Thermodynamics' (23-10-2018)
  • Glenn Barnich (Université Libre de Bruxelles) on `Electromagnetic edge modes and black hole entropy' (16-10-2018)
  • Avik Banerjee (Saha Institut of Nuclear Physics, India) on `Strings, Branes, Schwarzian action and Maximal Chaos' (09-10-2018)
  • Karapet Mkrtchyan (Max-Planck-Institut, Potsdam) on `Interactions of massless bosons in three dimensions' (02-10-2018)
  • Zoltan Bajnok (Wigner Research Centre, Budapest) will talk on `Integrable aspects of the AdS/CFT duality' (25-09-2018)
  • Thorsten Schimannek (Univ.  Bonn) on `Fourfolds, integral Fluxes and Modularity' (26-06-2018)
  • Prof. Martin Schnabl (Univ. Prag) on `Topological defects in open string field theory' (19-06-2018)
  • Prof. T. R. Govindarajan (Chennai, Indien) on `Should photon mass be zero?' (12-06-2018)
  • Peter Presnajder (Comenius University Bratislava) on `Quantum systems in relativistic fuzzy spaces' (05-06-2018)
  • Amihay Hanany (Imperial College London) on `Discrete Gauging and Small E8 instantons in six dimensions' (29-05-2018)
  • Gabriele Tartaglino-Mazzucchelli (KULeuven) on `Curvature squared invariants in 6D N=(1,0) supergravity' (08-05-2018)
  • Marcus Sperling (University of Vienna) on `Intersecting branes, Higgs sector, and chirality from N=4 SYM with soft SUSY breaking' (24-04-2018)
  • Linus Wulff (Masaryk University, Brno) on `Generalized supergravity and non-abelian T-duality anomaly' (17-04-2018)
  • Pascal Anastasopoulos (University of Vienna) on `Yukawas of light stringy states' (13-03-2018)
  • Peter Allmer (Vienna) on „Fusion of defects in Landau - Ginzburg models in a functorial approach“(23-01-2018)
  • Yihao Yin (Universidad Andres Bello, Santiago de Chile) on 'Vasiliev's equations, (A)dS backgrounds and perturbations' (12-01-2018)
  • Philip Hacker (TU Wien) on „Soft hairy warped black hole entropy“ (12-12-2017)
  • Nikola Gushterov (Oxford U.) on `Holographic Entanglement Density' (05-12-2017)
  • Daniel Fernandez (Iceland U.) on `Entanglement entropy at non-equilibrium in holography' (28-11-2017)
  • Athanasios Chatzistavrakidis (Rudjer-Boskovic-Institute Zagreb) on `Double Field Theory and Membrane Sigma Models' (21-11-2017)
  • Abhiram M. Kidambi (TU Wien) on `Calabi-Yau manifolds and sporadic groups' (14-11-2017)
  • Harold Steinacker (Uni Wien) on 'Quantized cosmological space-times from Yang-Mills matrix models' (07-11-2017)
  • Cedric Troessaert (MPI für Gravitationsphysik, Potsdam) on 'BMS4 at spatial infinity' (24-10-2017)
  • Shailesh Lal (Paris, LPTHE) on 'Quantum Effects in Higher Spin Holography and Tensionless AdS Strings' (17-10-2017)
  • Andrea Campoleoni (ETH Zürich) on 'Higher-spin BMS symmetries in four dimensions and soft theorems' (16-10-2017)
  • Harald Grosse (Uni Wien) on 'Quantum field theory models on noncommutative spaces' (12-10-2017)
  • Olaf Krüger (Uni Wien) on 'The Embedding of gauged N = 8 supergravity into 11 dimensions' (10-10-2017)
  • Jnanadeva Maharana (Institute of Physics, Bhubaneswar) on 'High energy behavior of scattering cross sections' (03-10-2017)
  • Christoph Roupec (Uni Wien) on 'Inflation in Supergravity' (27-06-2017)
  • Andjelo Samsarov (Ruder Boskovic Institute, Zagreb) on 'Black hole quasinormal modes in twisted models of matter minimally coupled to gravity' (30-05-2017)
  • Yang-Hui He on 'Calabi-Yau Volumes and Reflexive Polytopes' (23-05-2017)
  • Anton Alekseev (University of Geneva) on 'Path integrals for Wilson lines and Wilson surfaces' (16-05-2017)
  • Tristan McLoughlin (Trinity College Dublin) on 'Twistors and Conformal Higher-Spin Theory' (09-05-2017)
  • Stefano Cremonesi (Durham University) on 'The infrared physics of bad theories' (24-04-2017)
  • Harold Steinacker (Uni Wien) on `Covariant Quantum Spaces, the IKKT-model & Gravity' (04-04-2017)
  • Eric Bergshoeff (University of Groningen) on `Applied Newton-Cartan Geometry' (21-03-2017)
  • Volker Branding (Uni Wien) on `The full bosonic string as a geometric variational problem' (14-03-2017)
  • Rutger Boels (DESY, Hamburg) on `Minimal Quantum Field Theory' (31-01-2017)
  • Johanna Knapp (TUWien) on `Calabi-Yau compactifications and supersymmetric gauge theory' (24-01-2017)
  • Pan Kessel (MPI für Gravitationsphysik, Potsdam) on `Four-dimensional Vasiliev Theory : An Introduction' (17-01-2017)
  • Marcus Sperling (University of Vienna) on `Properties of the monopole formula' (10-01-2017)
  • Joris Raeymaekers (Prague) on `Multi-centered AdS3 solutions from Virasoro conformal blocks' (19-12-2016)
  • Yuhma Asano (DIAS, Dublin) on `Emergent geometries in the BMN matrix model' (13-12-2016)
  • Maja Buric (Belgrade University) on `Noncommutative spaces and differential geometry' (22-11-2016)
  • Miguel Tierz (Lisbon University) on `Matrix models and phase transitions in supersymmetric gauge theories in three dimensions' (15-11-2016)
  • Raimar Wulkenhaar (Münster) on `Exact solution of quantum field theory toy models' (08-11-2016)
  • Enrice Brehm (LMU, München) on `Classical Holographic Codes' (25-10-2016)
  • Andrea Campoleoni (ULB, Brussels) on `Higher spin theories from a Hamiltonian viewpoint' (18-10-2016)
  • Iva Lovrekovic (TUWien) on `Conformal gravity in four dimensions' (11-10-2016)