New Soft Theorems for Goldstone-Boson Amplitudes
New Soft Theorems for Goldstone-Boson Amplitudes
In this letter we discuss new soft theorems for the Goldstone boson amplitudes with non-vanishing soft limits. The standard argument is that the non-linearly realized shift symmetry leads to the vanishing of scattering amplitudes in the soft limit, known as the Alder zero. This statement involves certain assumptions of the …