Scattering Amplitudes from Soft Theorems and Infrared Behavior
Scattering Amplitudes from Soft Theorems and Infrared Behavior
We prove that soft theorems uniquely fix tree-level scattering amplitudes in a wide range of massless theories, including Yang-Mills, gravity, the nonlinear sigma model, Dirac-Born-Infeld, dilaton effective theories, extended theories like the $\mathrm{NLSM}\ensuremath{\bigoplus}{\ensuremath{\phi}}^{3}$ (nonlinear sigma model ${\ensuremath{\phi}}^{3}$), as well as some higher derivative corrections to these theories. We conjecture the …