Higher loop effective potentials in supersymmetric theories

Abstract

The famous AdS/CFT conjecture implies the existence of new nonrenormalisation theorems for the structure of low-energy effective actions in extended supersymmetric theories. The testing of these implications requires the explicit calculation of higher-loop corrections to the effective action for a variety of supersymmetric field theories. Two sectors of the low-energy supersymmetric effective action that are particularly interesting and amenable to calculations are the Kähler potential and that of the Euler-Heisenberg type. This talk will present recent results from some two-loop calculations made in beta-deformed supersymmetric Yang-Mills theory. Some new observations will also be given on the analytic structure of the sunset graph that is a key component of any two-loop effective potential calculation.