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Calendar of Physics Talks Vienna
| Introduction to Topological Insulators and Superconductors (Part 1) |
| Speaker: | Prof. Benoit Doucot (LPTHE, Paris-6) |
| Abstract: | In these lectures, I will present some of the important concepts in this field, starting from the Quantum
Hall effect, and several of its two-dimensional extensions by Haldane and Kane and Mele. Then, I will discuss
the "bulk-edge correspondence" which plays a crucial role for the possible applications of these
topological systems. Finally, I will present the key ideas behing the ten-fold classification. These lectures
will be self-contained, and mostly with a pedagogical goal. |
| Date: | Wed, 08.03.2017 |
| Time: | 16:00 |
| Duration: | 90 min |
| Location: | 10th floor seminar room in yellow tower of TU Wien Freihaus (Wiedner Hauptstrasse 8-10, A-1040 Vienna) |
| Contact: | Ayan Mukhopadhyay |
| On the smoothness of the cylinder at spatial infinity in vacuum spacetimes |
| Speaker: | Tim Paetz (Univ. Vienna) |
| Abstract: | It is well-known that spatial infinity cannot be represented as a regular point due to blow-ups of the Weyl tensor whenever the ADM mass is non-zero. Because of this, the construction of vacuum spacetimes which admit a smooth past and future null infinity turns out to be a rather intricate problem. An approach which avoids these blow-ups is a cylinder representation of spatial infinity. However, for generic initial data the solutions will pick up log-terms at the critical sets where the cylinder "touches" null infinity. The goal of this talk is to set up an asymptotic initial value problem with data at past null infinity and to derive necessary conditions for the smoothness of these critical sets. |
| Date: | Thu, 09.03.2017 |
| Time: | 14:00 |
| Location: | Arbeitsgruppe Gravitation, Währinger Strasse 17, Raum 218, 2. Stock, 1090 Wien |
| Contact: | P.T. Chrusciel |
| Calabi-Yau fourfolds with non-trivial three-form cohomology |
| Speaker: | Sebastian Greiner (MPP Munich & Utrecht) |
| Abstract: | In this seminar, we will discuss various aspects of Calabi-Yau fourfolds, relevant for M- and F-theory effective actions in three and four dimensions. First, we perform a dimensional reduction of type IIA supergravity on a general Calabi-Yau fourfold and then apply mirror symmetry at the large volume/large complex structure point to gain information about the non-trivial three-form cohomology of the fourfold. In the second part, we discuss an explicit construction of Calabi-Yau fourfolds as toric hypersurfaces. In course of this discussion we develop tools to compute the metric on the three-form cohomology that arises in the effective action of type IIA supergravity on the fourfold. |
| Date: | Thu, 09.03.2017 |
| Time: | 16:00 |
| Location: | TU Wien, seminar room, 10 Floor E136 (Yellow tower), Wiedner Hauptstr. 8-10, 1040 Wien |
| Contact: | Abhiram M Kidambi (TU Wien, ITP) |
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