Hidden Structures in Super Form Factors
Abstract
Maximally supersymmetric Yang–Mills theory in four dimensions has remarkable features such as conformal symmetry at the quantum level, evidence of integrability and the existence of a well defined holographic dual. The associated perturbative S-matrix and the mysterious roots of its striking simplicity are part of an active area of research which has recently witnessed enormous progress in making many of its special features manifest. These successes have led to the question of whether such hidden structures are necessarily confined to the realm of the S-matrix or whether they can also illuminate other aspects of the theory. The first step towards the study of more “off-shell quantities” is represented by supersymmetric form factors. In the first part of the thesis, we propose formulas for any tree-level form factor of the stress-tensor multiplet, derived from twistor worldsheet models. These are the analogue of the ones introduced for amplitudes, both in the twistor and in the more recent ambitwistor formulation. Another important line of research originates from the AdS/CFT correspondence. In this context, amplitudes are shown to be T-dual to polygonal lightlike Wilson loops. From the point of view of form factors, the dual holographic picture is that of a periodic lightlike Wilson line. The existence of such a picture constitutes a strong indication of invariance under dual conformal transformations. In the second part of the thesis, we give a prescription for the definition of a canonical integrand for super form factors at one loop in terms of region variables in dual space. This allows us to derive recursion relations at loop level and to study the properties of the resulting expressions under the action of dual conformal generators. We show that the dual conformal anomaly for an arbitrary number of particles and generic helicities matches the expression known for the amplitude case.
Authors
Panerai, RCollections
- Theses [4203]