# Yangian symmetry for bi-scalar loop amplitudes

Journal of High Energy Physics, May 2018

Abstract We establish an all-loop conformal Yangian symmetry for the full set of planar amplitudes in the recently proposed integrable bi-scalar field theory in four dimensions. This chiral theory is a particular double scaling limit of γ-twisted weakly coupled $$\mathcal{N}=4$$ SYM theory. Each amplitude with a certain order of scalar particles is given by a single fishnet Feynman graph of disc topology cut out of a regular square lattice. The Yangian can be realized by the action of a product of Lax operators with a specific sequence of inhomogeneity parameters on the boundary of the disc. Based on this observation, the Yangian generators of level one for generic bi-scalar amplitudes are explicitly constructed. Finally, we comment on the relation to the dual conformal symmetry of these scattering amplitudes.

This is a preview of a remote PDF: https://link.springer.com/content/pdf/10.1007%2FJHEP05%282018%29003.pdf

Dmitry Chicherin, Vladimir Kazakov, Florian Loebbert, Dennis Müller, De-liang Zhong. Yangian symmetry for bi-scalar loop amplitudes, Journal of High Energy Physics, 2018, 3, DOI: 10.1007/JHEP05(2018)003