I will explain how to describe form factors of single-trace half-BPS operators in planar N=4 super Yang Mills theory using the T-dual Wilson loop picture. After reviewing earlier results for operators in the stress-tensor multiplet, I will present the dual Wilson loop description for the so-called MHV form factors of half-BPS operators. The general proposal relates these form factors to the matrix elements of a null periodic super Wilson loop with outgoing states composed of zero-momentum scalars. I will present perturbative tests of this description at weak coupling. I will then explain how to obtain exact result at finite coupling in the collinear limit using the Wilson loop Operator Product Expansion. I will conclude with general comments and speculations about form factors of unprotected operators such as the Konishi operator.

I will talk about the behaviour of gluon scattering amplitudes in planar N=4 SYM near kinematical corners coined Origins where maximally-helicity-violating amplitudes are expected to be exactly Gaussian in the logs of the cross ratios and exactly predictable. In part 1, I will recall how much is known about this behaviour for the 6-gluon amplitude and interpret the result as a sort of quantum area convoluting the minimal surface TBA data with an effective coupling constant, known as the tilted cusp anomalous dimension. In part 2, I will present a generalization to any number of gluons and explore (some bit of) the emerging parterre of Origins. If time permits, I will discuss applications to scattering amplitudes in the null limit where all two-particle Mandelstam vanish simultaneously. The talk is based on a work in progress with Lance Dixon, Yu-Ting Liu and Georgios Papathanasiou. ---- Part of the London Integrability Journal Club. If you are a new participant please register at integrability-london.weebly.com. The link will be emailed.

I will present a framework for computing correlators of three single trace operators in planar N=4 SYM theory that uses hexagonal patches as building blocks. This approach allows one to exploit the integrability of the theory and derive all loop predictions for its structure constants. After presenting the main ideas and results, I will discuss recent perturbative tests and open problems.

In this talk I will explain how to compute gluon scattering amplitudes at finite coupling in planar N=4 SYM theory, using the duality with null polygonal Wilson loops, conformal symmetry, and the integrability of the colour flux tube dynamics. After introducing the main ideas and results, I will present some applications of this formalism at strong coupling and discuss the validity of the semiclassical (dual) string description.

In this talk, I will explain how to compute gluon scattering amplitudes in planar N=4 Super-Yang-Mills theory using the flux tube (OPE) picture. The latter, which builds on the duality with light-like Wilson loops, provides a description of scattering amplitudes in terms of excitations evolving on a two-dimensional background. Exploiting the remarkable integrable structures of this background, one can formulate scattering amplitudes, at any values of the 't Hooft coupling, as an expansion around the multi-collinear (a.k.a. OPE) limit. I shall report on recent progress made in this direction and speculate on its possible application to the study of scattering amplitudes in the multi-Regge kinematics.