# Vendredi 10 novembre 2017

11h00 – 12h00, Amphi 5 du CPT

### Moving frames on Finsler surfaces

#### Vasile Sorin SABAU

In this talk we will use the method of moving frames for describing the existence and construction of a Finsler structure of constant flag curvature $K=1$ as well as Finsler structure with vanishing Landsberg curvature. The method is basically based on the Cartan double fibration and was developed initially by R. Bryant. It is remarkable that Riemannian surfaces with special geodesic properties actually induce Finsler metrics with prescribed curvature conditions. The research goes in the opposite direction as well. Some new Riemannian metrics might be induced by such Finsler structures.

14h00 – 15h00, Amphi 5 du CPT

### Extracting scattering observables and resonance properties from lattice QCD

#### Max Hansen (CERN)

QCD, the quantum theory of the strong force, gives rise to a rich variety of short-lived resonance states. Understanding these in detail is of great interest, both for predicting backgrounds in new-physics searches and for gaining general insight into strong-force dynamics and phenomenology. The numerical technique of lattice QCD (LQCD), which has proven very successful in studying the properties stable hadrons, should also play an important role in reaching a comprehensive, quantitative picture for states that decay via the strong force. In this talk, I will review methods for calculating resonance properties in LQCD with a particular focus on three-particle decay channels. I will explain how the restriction to a finite volume can used as a tool, rather than an unwanted artifact. In addition, I will highlight the future steps required for achieving rigorous LQCD calculations of excited nucleon and exotic meson states.

novembre 2017 :