2024/12/04 by Ni, Yu-Han, Wang, Yi-Ning, Wu, Chao +1
#FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #High Energy Physics - Theory (hep-th)
paper · doi:10.48550/arxiv.2412.03762
We identify an extended Poincare symmetry ISO(2) × ISO(3,1) for on-shell massive scattering amplitudes, transforming under the U(2) Little group symmetry. Thus the one-particle state involves in both spin and transversality t (related to chirality), and the spin-spinors are extended to the spin-transverality spinors. The massive spin-s spinors with different transversality can be related by the SO(5,1) symmetry, although the U(2) Little group breaks the symmetry explicitly. The three-point massive amplitudes can be fully determined from the T^± and m generators, diagrammatically denoted as the mass insertion and chirality flip, which provide correspondence between massless ultraviolet and massive chiral-eigenstate amplitudes. Thus the massless on-shell technique can be utilized to construct higher-point tree- and loop-level massive amplitudes.