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arXiv · 2502.03481

Perturbative soft graviton theorems in de Sitter spacetime

Divyesh N. Solanki·Pratik Chattopadhyay·Srijit Bhattacharjee
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Abstract

We consider soft graviton scattering for a theory where Einstein's gravity is minimally coupled to a scalar field in the presence of a cosmological constant, i.e. in a background de Sitter space. Employing a perturbative expansion in a small cosmological constant, we compute leading, subleading and sub-subleading corrections to Weinberg's soft graviton amplitude for the tree-level scatterings in the static patch of de Sitter space. We observe similar universal features of the soft graviton amplitude as found in [JHEP10(2023)055] for the soft photons.

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Divyesh N. Solanki, Pratik Chattopadhyay, Srijit Bhattacharjee. 2025-01-28. Perturbative soft graviton theorems in de Sitter spacetime. https://doi.org/10.1007/jhep12(2025)008

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