Radiation of scalar modes and the classical double copy

Understand

The double copy procedure relates gauge and gravity theories through color-kinematics replacements and holds for both scattering amplitudes and in classical contexts.

• Moreover, it has been shown that there is a web of theories whose scattering amplitudes are related through operations that exchange color and kinematic factors.
• In this paper, we generalize and extend this procedure by showing that the classical perturbative double copy of pions corresponds to special Galileons.
• We consider point-particles coupled to the relevant scalar fields, and find the leading and next to leading order radiation amplitudes.