Double-soft behavior for scalars and gluons from string theory

Understand

We compute the leading double-soft behavior for gluons and for the scalars obtained by dimensional reduction of a higher dimensional pure gauge theory, from the scattering amplitudes of gluons and scalars living in the world-volume of a Dp-brane of the bosonic string.

• In the case of gluons, we compute both the double-soft behavior when the two soft gluons are contiguous as well as when they are not contiguous.
• From our results, that are valid in string theory, one can easily get the double-soft limit in gauge field theory by sending the string tension to infinity.