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Calendar of Physics Talks Vienna
| Gravity as graded spacetime (quantum) mechanics |
| Speaker: | Peter Schupp (Jacobs Univ. Bremen) |
| Abstract: | Electromagnetic interactions can be introduced by a deformation of the canonical commutation relations, as a slightly more general alternative to the usual minimal coupling prescription. We show that the same is true for gravitational interactions, but graded manifolds are required. As an application we present a slick derivation of the bosonic part of the supergravity (string effective) action. The construction provides a novel, somewhat more algebraic interpretation of the key ingredients of general relativity. The mathematical setting is Hitchin's generalized geometry. |
| Date: | Tue, 11.12.2018 |
| Time: | 13:45 |
| Duration: | 60 min |
| Location: | TU Wien, Getreidemarkt 9, Maschinenbaugebäude, 1. Stock, HS Kleiner Schiffbau |
| Contact: | S. Fredenhagen, D. Grumiller |
| Standard Model parton distributions at very high energies |
| Speaker: | Bryan Webber (Cavendish Lab, Cambridge) |
| Abstract: | At energies far above the electroweak scale, electroweak symmetry is restored
and the parton distribution functions of the proton receive contributions from
all the Standard Model fermions and bosons. Fundamentally new phenomena
appear, such as self-polarisation, mixed PDFs and double-logarithmic evolution.
I will discuss the evolution of the 60 SM PDFs of the unpolarised proton according
to the SU(3), SU(2), U(1), mixed SU(2)×U(1) and Yukawa interactions, and show
that it can lead to important corrections to parton luminosities at a future 100 TeV
collider.
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| Date: | Tue, 11.12.2018 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | A. Hoang, H. Neufeld, S. Plätzer, M. Procura |
| From quantum reference systems to quantum general covariance |
| Speaker: | Philipp Höhn (ESI) |
| Abstract: | Despite its importance in general relativity, a quantum notion of general covariance has not yet been established in quantum gravity and cosmology, where, given the a priori absence of coordinates, it is necessary to replace classical frames with dynamical quantum reference systems. As such, quantum general covariance bears on the ability to consistently switch between the descriptions of the same physics relative to arbitrary choices of quantum reference systems. In this talk, I will summarize a recent systematic method for such switches, which works in analogy to coordinate changes on a manifold, except that these `quantum coordinate changes' proceed between different Hilbert spaces.
I will illustrate this method by means of spatial quantum reference frames and a simple quantum cosmological model. Time permitting, I might also disucss conceptual implications for quantum gravity. |
| Date: | Thu, 13.12.2018 |
| 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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