On Cancellations of Ultraviolet Divergences in Supergravity Amplitudes

Understand

Concrete calculations have pointed out that amplitudes in perturbative gravity exhibit unanticipated cancellations taming their ultraviolet behaviour independently of supersymmetry.

• Similar ultraviolet behaviour of N=4 super-Yang-Mills and N=8 maximal supergravity has explicitly been observed until three loops.
• These cancellations can be connected to two manifest features of gravitational theories: firstly gauge invariance from diffeomorphism symmetries and secondly that amplitudes are colourless and exhibits crossing symmetry.
• We will give a simple physical explanation of the cancellations exhibited in gravity amplitudes.