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Calendar of Physics Talks Vienna
| Topological photons and phonons in nanophotonic systems |
| Speaker: | Ewold Verhagen (CoQuS) |
| Abstract: | For further information please visit: www.coqus.at |
| Date: | Mon, 09.12.2019 |
| Time: | 16:30 |
| Duration: | 120 min |
| Location: | Universität Wien, Lise Meitner-Hörsaal, Strudelhofgasse 4, 1090 Wien |
| Contact: | Susanne Ninaus-Meznik |
| Non-relativistic expansion of general relativity |
| Speaker: | Jelle Hartong (University of Edinburgh) |
| Abstract: | Joint TU/UV Theory Seminar: I will discuss recent progress in the 1/c expansion of general relativity where c is the speed of light.
This is an off shell and covariant approximation of general relativity that is similar to the post-Newtonian approximation.
I will show that it provides an action principle for matter coupled Newton-Cartan gravity which on shell is described by torsionless Newton-Cartan geometry.
For certain choices of matter, instead of leading to Newton-Cartan gravity, it rather gives rise to matter coupled Galilean gravity and I will discuss these cases as well.
Finally, time permitting, I will end with some comments about the 1/c expansions of the Nambu-Goto and Polyakov actions for strings. |
| Date: | Tue, 10.12.2019 |
| Time: | 13:45 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | S. Fredenhagen, D. Grumiller |
| The perturbative gradient flow |
| Speaker: | Robert Harlander (RWTH Aachen University) |
| Abstract: | im Rahmen des Teilchenphysikseminars: The so-called Yang-Mills gradient flow has become a successful concept in lattice calculations during the last few years. Besides its technical virtues in the non-perturbative regime, it was shown to be accessible in perturbation theory as well.
In this talk, I present a number of promising applications, among them a potential extraction of $\alpha_s(M_Z)$ from first-principle calculations, and a novel lattice definition of the energy-momentum tensor.
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| Date: | Tue, 10.12.2019 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | A. Hoang, S. Plätzer |
| Theoretical study on solid‐state high‐harmonic generation reflecting spatiotemporal symmetries of systems |
| Speaker: | Yasushi Shinohara (University of Tokyo) |
| Abstract: | The Spatial symmetry of a system can be encoded in an emitted photon of high‐order harmonic generation (HHG) driven by a strong electric field [1].In the conventional treatment of nonlinear optics based on perturbative expansion, selection rules of each harmonic well pronounce the symmetry through susceptibilities. We have a question that the election rules still hold even within the nonperturbative regime in which the n‐th harmonic yield does not obey n‐th order of the intensity power anymore, or not. The answer is partially given for circularly polarized light by Ref. [2]. In this talk, we would like to present current trials to answer the question. Firstly, we will introduce a work that collaboration with experimentalists, HHG from GaSe [3]. In this experiment, perpendicular components of the emitted photon to the applied electric field reveal a symptom beyond perturbative expansion. |
| Date: | Wed, 11.12.2019 |
| Time: | 14:15 |
| Location: | Seminar room FH gelb 10, Institute for Theoretical Physics – Vienna University of Technology, Wiedner Hauptstraße 8 – 10, 10th floor, B (yellow tower) |
| Contact: | Joachim Burgdörfer |
| Hadronic effects and effective field theories at the precision frontier |
| Speaker: | Peter Stoffer (University of California, San Diego) |
| Abstract: | Traditionally,low-energy precision experiments have taken a complementary role to direct searches for physics beyond the Standard Model(SM)at high-energy colliders.The absence of direct signals of new physics at the LHC makes it plausible that particles beyond the SM are much heavier than the electroweak scale. Therefore, collider experiments also play the role of precision indirect searches.Effective field theories(EFTs)provide a model-independent unified framework for describing and constraining new physics in experiments from LHC energies down to the hadronic scale.The increasing precision at the experimental frontier calls for a better control of theory uncertainties, which at low energies are usually dominated by non-perturbative hadronic effects. Theoretical progress is required both in the description of hadronic SM contributions, as well as in the EFT description of new physics. |
| Date: | Wed, 11.12.2019 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Kleiner Seminarraum, Boltzmanngasse 5, 5. Stock |
| Contact: | A. Hoang, S. Plätzer, M. Procura |
| Aerosol Optics, Radiative Forcing, and Climate Change |
| Speaker: | Hans Moosmüller, Desert Research Institute |
| Abstract: | The talk takes place in the frame of the first VDSP Science Day.
Please register:
https://vds-physics.univie.ac.at/activities/science-day/ |
| Date: | Thu, 12.12.2019 |
| Time: | 10:50 |
| Duration: | 60 min |
| Location: | Sky Lounge, OMP |
| Contact: | VDS Physics |
| Stability of the positive mass theorem for axisymmetric manifolds |
| Speaker: | Edward Bryden (Tübingen) |
| Abstract: | Im Rahmen des Literaturseminars: We investigate the stability of the Positive Mass Theorem for three-dimensional axisym-
metric manifolds. It is widely known that asymptotically at manifolds with nonnegative
scalar curvature have nonnegative ADM mass, and that the only asymptotically at
manifold with nonnegative scalar curvature and zero ADM mass is Euclidean space.
We will show that axisymmetric manifolds with nonnegative scalar curvature and small
ADM mass, and which satisfy an additional technical assumption, are close to Euclidean
space in a Sobolev sense.
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| Date: | Thu, 12.12.2019 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Arbeitsgruppe Gravitation, Währinger Strasse 17, Raum 218, 2. Stock, 1090 Wien |
| Contact: | P.T. Chrusciel, D. Fajman |
| MIGA, a large underground infrastructure using matter-waves to study geophysics and general relativity |
| Speaker: | Philippe Bouyer, Institut d'Optique |
| Abstract: | The talk takes place in the frame of the first VDSP Science Day.
Please register:
https://vds-physics.univie.ac.at/activities/science-day/ |
| Date: | Thu, 12.12.2019 |
| Time: | 14:10 |
| Duration: | 60 min |
| Location: | Sky Lounge, OMP |
| Contact: | VDS Physics |
| 2D Materials are like people – it is the defects that make them interesting |
| Speaker: | Sarah Haigh, University of Manchester |
| Abstract: | The talk takes place in the frame of the first VDSP Science Day.
Please register:
https://vds-physics.univie.ac.at/activities/science-day/ |
| Date: | Thu, 12.12.2019 |
| Time: | 16:20 |
| Duration: | 60 min |
| Location: | Sky Lounge, OMP |
| Contact: | VDS Physics |
| Differential equations and iterated integrals for massive multi-loop Feynman integrals |
| Speaker: | Stefano Di Vita (INFN Mailand) |
| Abstract: | In this talk I will give an overview of the differential equations method for the calculation of multi-loop Feynman integrals, which was recently applied to several
cases where massive legs and propagators are present.
I will discuss how the systems of differential equations arise, how they are brought
in canonical form with the help of the Magnus exponential, what functions can be
used to give a closed-form representation of the solution, and how they are analytically continued to the kinematic regions of interest.
Some examples will be given, such as the master integrals for the NNLO QED corrections to mu-e scattering, which are crucial for the physics program of MUonE, an experiment proposed with the goal of determining the leading hadronic contribution to the muon
g-2 in a novel way.
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| Date: | Fri, 13.12.2019 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | A. Hoang, S. Plätzer, M. Procura |
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