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Calendar of Physics Talks Vienna
| Machine learning and SU(3) structures on six manifolds. |
| Speaker: | James Gray (Virginia Tech) |
| Abstract: | In this talk we will discuss the application of Machine Learning techniques to obtain numerical approximations to various metrics of SU(3) structure on Calabi-Yau manifolds. More precisely, we will be interested in SU(3) structures whose torsion classes make them suitable backgrounds for various string compactifications. A variety of aspects of this topic will be covered. These will include learning moduli dependent Ricci-Flat metrics on Calabi-Yau threefolds and obtaining numerical approximations to torsional SU(3) structures. |
| Date: | Tue, 02.03.2021 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | https://moodle.univie.ac.at/mod/bigbluebuttonbn/guestlink.php?gid=x8o6ILSKJuC9 |
| Contact: | Céline Zwikel |
| TUgitLab - Using a modern version control and workflow system for scientific projects |
| Speaker: | Richard van Nieuwenhoven (TU Wien, Institut für Angewandte Physik) |
| Abstract: | TU.it provides a free internal GitLab instance for scientific projects and students. Initially
developed for Software development, GitLab can function as a platform for research
projects. Many scientific projects correspondingly facilitate managing data collections, data
processing, progress monitoring (scripts/programs) and all kind of documentation. GitLab is
flexible, and the workflows can be adapted to the specific needs of most research projects.
The initial effort to master git version control is relatively high, but the usage will pay off very
fast. This presentation will give a compressed overview of the core GitLab capabilities. To
demonstrate the practical benefits of GitLab, subsequent hands-on workshops can be
provided for your specific project (free of charge for IAP members). |
| Date: | Tue, 02.03.2021 |
| Time: | 16:00 |
| Location: | Zoom Meeting https://us02web.zoom.us/j/81476909411 Meeting ID: 814 7690 9411 |
| Contact: | Dr. I.C. Gebeshuber |
| Causal Relations At Infinity |
| Speaker: | Peter Cameron (Cambridge) |
| Abstract: | Motivated by a possible quantum gravity construction, Penrose has shown that, despite being asymptotically flat, there is an inconsistency between the causal structure at infinity of Schwarzschild and Minkowski spacetimes. However, the proof of this inconsistency is specific to 4 spacetime dimensions. In this talk I will discuss how this result extends to higher (and lower) dimensions. More generally, I will consider examples of how the causal structure of asymptotically flat spacetimes are affected by dimension and by the presence of mass (both positive and negative). I will then show how these ideas can be used to prove a higher dimensional extension of the positive mass theorem of Penrose, Sorkin and Woolgar. |
| Date: | Thu, 04.03.2021 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | ZOOM: https://univienna.zoom.us/j/6540036841?pwd=SytyVkZJZzNyRG9lMm13ejlHeHRRUT09 Meeting ID: 654 003 6841 Passcode: Gs4brS |
| Contact: | Piotr Chrusciel, David Fajman |
| Unimodular vs Nilpotent Superfield Approach to Pure dS Supergravity |
| Speaker: | Sukruti Bansal (Chulangkorn University, Bangkok) |
| Abstract: | Recent progress in understanding de Sitter spacetime in supergravity and string theory has led to the development of a 4D supergravity with spontaneously broken supersymmetry allowing for de Sitter vacua, also called de Sitter supergravity. One approach makes use of constrained (nilpotent) superfields, while an alternative one couples supergravity to a locally supersymmetric generalization of the Volkov-Akulov goldstino action. These two approaches have been shown to give rise to the same 4D action.
A novel approach to de Sitter vacua in supergravity involves the generalisation of unimodular gravity to supergravity using a super-Stückelberg mechanism. We make a connection between this new approach and the previous two. We show that upon appropriate field redefinitions, the 4D actions match up to the cubic order in the fields. [...] |
| Date: | Thu, 04.03.2021 |
| Time: | 16:30 |
| Duration: | 60 min |
| Location: | https://tuwien.zoom.us/j/95482849369?pwd=SkU2WU5hMVJBQWsyVlFXRlRvQlIvdz09 |
| Contact: | Laura Donnay, David Andriot, Niccolo Cribiori |
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