|
Calendar of Physics Talks Vienna
| Renormalization in large-N QCD and open/closed string duality |
| Speaker: | Marco Bochicchio (INFN Roma) |
| Abstract: | We demonstrate that the asymptotic freedom and renormalization group imply that the large-N ’t Hooft expansion of the YM S matrix is ultraviolet(UV)finite nonperturbatively,while the large-N expansion of the QCD S matrix is only renormalizable,due to UV divergences starting from the order of N_f/N,with N_f the number of quark flavors.We investigate the compatibility of the aforementioned renormalization properties with the existence of a supposed canonical string solution, matching the topology of ’t Hooft large-N expansion,for the S matrix of large-N YM theory and QCD.The UV finiteness of the large-N YM S matrix is compatible with the universally believed UV finiteness of closed string theories.Yet,we demonstrate that the aforementioned renormalization properties of the large-N QCD S matrix to the order of N_f/N are incompatible with the open/closed string duality of the would-be .... |
| Date: | Tue, 09.04.2019 |
| Time: | 13:45 |
| Duration: | 60 min |
| Location: | TU Wien, Wiedner Hauptstraße 8, Yellow Area, 9th floor, Seminar Room DB 09 E23 |
| Contact: | S. Fredenhagen, D. Grumiller |
| Matching non-relativistic EFT and dispersion relations for η → 3π decays |
| Speaker: | Jan Lüdtke (Univ. Wien) |
| Abstract: | The decay of an eta meson into three pions is exactly forbidden in the isospin limit.
In fact it can be shown that the amplitude is proportional to a ratio of quark masses involving the difference of the squared up and down quark masses making it an ideal process to study the strength of isospin breaking in the strong sector. In this talk I will introduce three different formalisms to describe the decay amplitude: chiral perturbation theory, dispersion relations and non-relativistic EFT. I will point out the strengths and weaknesses of the different formalisms and show how one can ideally combine them to describe the momentum dependence and extract the quark mass ratio.
|
| Date: | Tue, 09.04.2019 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | A. Hoang, S. Plätzer, M. Procura |
| Lensing and birefringence of light in the Schwarzschild metric |
| Speaker: | Thomas Schuck (Marseille) |
| Abstract: | im Rahmen des Literaturseminars: The equations of motion of massless test particles with spin are discussed and solved
in the Schwarzschild metric.
|
| Date: | Thu, 11.04.2019 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Arbeitsgruppe Gravitation, Währinger Strasse 17, Raum 218, 2. Stock, 1090 Wien |
| Contact: | P.T. Chrusciel, D. Fajman |
| The use of Standard Model Effective Field Theory to analyze Higgs boson measurements at e+e- colliders |
| Speaker: | Michael E. Peskin (SLAC, Stanford University) |
| Abstract: | 2. Vorlesung im Rahmen der Schördinger-Gastprofessur 2019 |
| Date: | Fri, 12.04.2019 |
| Time: | 16:15 |
| Duration: | 60 min |
| Location: | Fakultät für Physik, Erwin-Schrödinger-Hörsaal, Boltzmanngasse 5, 5. Stock |
| Contact: | A. Hoang, H. Neufeld |
|