Description |
In this talk we discuss two instances of hidden symmetries in four- dimensional scattering amplitudes. Firstly, we motivate how to obtain simple 4d integrable field theories as limits of planar twisted N=4 super Yang- Mills theory. Amplitudes in these new theories are in one-to-one correspondence with Zamolodchikov's fishnet Feynman graphs and generalizations thereof. Their relation to the planar AdS/CFT duality implies that large families of mostly unsolved Feynman integrals inherit a conformal Yangian symmetry. We then show that also tree-level scattering in ordinary Einstein gravity possesses a hidden conformal Lie algebra symmetry. The inspiration for the latter finding originates in soft limits of string theory scattering amplitudes. Curiously, our formulation of this symmetry relies on a manifestly permutation symmetric form of the graviton amplitude.
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