HET-Discovery seminar: Henrik Johansson

Speaker:  Henrik Johansson

Title: Amplitudes with reduced supersymmetry in gauge theory and gravity

Abstract: In this talk I will discuss the construction of scattering amplitudes with reduced supersymmetry using methods that include: supersymmetric decomposition, unitarity method, color-kinematics duality, double copy and modern integration techniques. The methods apply quite generally to N ≤ 2 supersymmetric gauge theories and N ≤ 4 supergravity theories. However, this talk will mainly focus on N=2 super-Yang-Mills with SU(N_c) gauge group and N_f massless hypermultiplets, and explicitly construct the fully integrated four-vector amplitude at two loops. By construction the amplitude obeys color-kinematics duality, which means that it can be easily recycled for the construction of two-loop amplitudes in various supergravities via the double-copy formalism. I will discuss in some detail which supergravity theories this gives us access to, and why these supereravities are of theoretical interest.