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Calendar of Physics Talks Vienna
| Emergent spacetime from the bosonic master field of the IIB matrix model |
| Speaker: | Frans R. Klinkhamer (Institute for Theoretical Physics, Karlsruhe Institute of Technology) |
| Abstract: | The IIB matrix model has been suggested as a particular formulation of nonperturbative superstring theory (M-theory).
It has now been realized that the emerging classical spacetime may reside in its large-N master field.
This bosonic master field can, in principle, give rise to Minkowski and Roberson-Walker spacetimes.
The outstanding task is to solve the bosonic master-field equation, which is essentially an algebraic equation.
First results have been obtained for small values of the matrix size N.
This talk focuses on the basic ideas and open questions, while skipping most of the technical details. |
| Date: | Tue, 08.03.2022 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Zoom meeting invitation - Joint Theory Seminar https://univienna.zoom.us/j/62319522606?pwd=RVBCSmVxSjNpNEpwQXJJU3QyK3lHUT09 ID Meeting: 623 1952 2606 Passcode: 273702 |
| Contact: | D. Grumiller, S. Fredenhagen, E. Battista, R. Ruzziconi |
| Dynamic surface processes viewed by scanning tunneling microscopy |
| Speaker: | Peter Matvija (Charles University Prague, Department of Surface and Plasma Science) |
| Abstract: | Scanning tunneling microscopy (STM) has at its core a very simple idea: a sharp metallic needle is approached very close to a conductive surface while a bias voltage between the tip and the surface is applied. Thanks to this simple principle a wide variety of surface structures and processes have been studied and revealed.
To keep surfaces clean and to keep atoms stationary during the measurement, STM experiments are often carried out in ultra-high vacuum and cryogenic temperatures. It makes experiments simpler and makes results easier to interpret. However, it also makes experiments more distant from applications that usually operate at room (or higher) temperature and in atmospheric (or higher) pressure.
In this talk, we will present the results of two sets of STM studies executed either at room (or elevated) temperature or at elevated pressure. The first set of studies deals with the |
| Date: | Tue, 08.03.2022 |
| Time: | 16:00 |
| Location: | The seminar will be held as a Zoom Meeting https://tuwien.zoom.us/j/96062751637?pwd=ZkRUWnlkUFFZb2pEdm55ZzFteTBNdz09 Meeting ID: 960 6275 1637 Password: 9ANd8XWj |
| Contact: | Univ.Prof. Dr. Ulrike Diebold |
| Getting discrete - Improving an interfering optical lattice setup |
| Speaker: | Stephan Roschinski (ETH Zürich) |
| Abstract: | Optical lattices provide a promising plattform for quantum simulation combining versatility with good experimental control. The interfering optical lattice setup we use will be introduced as well as the difficulties in intensity and phase stabilization arising with the use of interfering beams. We will introduce the experimental upgrades planned to address these problems. An analysis of the chosen beam frequencies will be given using Floquet theory before concluding with a brief introduction of the role of topology. |
| Date: | Wed, 09.03.2022 |
| Time: | 14:00 |
| Duration: | 45 min |
| Location: | Seminarraum ATI |
| Contact: | Julian Leonard |
| Examples of naked singularities for the Einstein-Euler system |
| Speaker: | Mahir Hadzic (UC London) |
| Abstract: | In 1990, based on numerical and formal asymptotic analysis, Ori and Piran predicted the existence of self-similar spacetimes, called relativistic Larson-Penston solutions,
that can be suitably flattened to obtain examples of spacetimes that dynamically form naked singularities from smooth initial data, and solve the radially symmetric
Einstein-Euler systemwith sufficiently small sound speed. I will explain a rigorous mathematical construction of such spacetimes. Joint work with Yan Guo and Juhi Jang. |
| Date: | Thu, 10.03.2022 |
| Time: | 15:00 |
| Duration: | 60 min |
| Location: | https://univienna.zoom.us/j/6540036841?pwd=SytyVkZJZzNyRG9lMm13ejlHeHRRUT09 Meeting ID: 654 003 6841 Passcode: Gs4brS |
| Contact: | P. Chrusciel, D. Fajman |
| Scalar Fields in 3D Asymptotically Flat Higher-Spin Gravity |
| Speaker: | Max Riegler (University of Vienna) |
| Abstract: | In this talk I present the construction of a novel associative algebra and use it to define a theory of higher-spin gravity in (2+1)-dimensional asymptotically flat spacetimes. This construction is based on a quotient of the universal enveloping algebra of the Poincare algebra with respect to the ideal generated by its Casimir elements, the mass squared and the three-dimensional analogue of the square of the Pauli-Lubanski vector. Furthermore I will show how to consistently couple a scalar field to an higher-spin gauge theory using a sub-structure of this novel algebra. |
| Date: | Thu, 10.03.2022 |
| Time: | 16:30 |
| Duration: | 60 min |
| Location: | Freihaus, Sem.R. DB gelb 09 |
| Contact: | Iva Lovrekovic |
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