Abstract The perturbative corrections to soft photon theorems with massive scalars in de Sitter spacetime were computed in (Bhatkar and Jain in J High Energy Phys 2023:55, 2023). However, the massless limit of the scalar modes is ill-defined in their work. It therefore is ambiguous to take the massless limit of the soft factors. In this paper, we derive the massless scalar modes in d -dimensional de Sitter spacetime and use it to compute the perturbative corrections to the leading and sub-leading soft photon theorems. Our framework corresponds to tree level scattering of massless scalars followed by an emission of a soft photon in a compact region of the static patch of de Sitter. We show that our results are consistent with (Bhatkar and Jain in J High Energy Phys 2023:55, 2023) in the massless limit and we comment on the universality of our results.
Pratik Chattopadhyay (Fri,) studied this question.