Scattering Amplitudes: new perspectives on Feynman Integral Calculus

by Dr Pier Paolo Mastrolia (Max-Planck-Institut fuer Physik e Universita' di Padova)

Thursday 23 Jan 2014, 08:00 → 09:30 Europe/Rome

Sala Riunioni (Dipartimento di Fisica e Astronomia)

I discuss about the fundamental role played by scattering amplitudes at the core of Quantum Field Theory. I elaborate on how qualitative properties of the S-Matrix, such as Unitarity and Analiticity, turn into powerful methods for the quantitative determination of Feynman amplitudes. I show that there exists a unique and simple framework underlying scattering amplitudes to all orders in perturbation theory, which is based on Cauchy's Residue Theorem and Multivariate Polynomial Division. I present the dramatic impact of these new methods, not only on the study of more theoretical aspects of QFT, but, very importantly, on collider phenomenology. Relevance is given to Higgs boson associated production at the LHC, recently determined at an unprecedendel level of accuracy: one of the most beautiful calculation ever performed with Feynman diagrams. I present a new methods for computing Feynman integrals based on the solution of sytems of differential equations by means of Magnus series. I will conclude with the possible investigation paths which can be accessed by our novel understanding of Feynman calculus, which complements the original work of Landau and Cutkosky.

Slides mastrolia_BO.pdf