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arXiv · 2102.06165

Soft Photon theorem in the small negative cosmological constant limit

Nabamita Banerjee·Karan Fernandes·Arpita Mitra
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Abstract

We study the effect of electromagnetic interactions on the classical soft theorems on an asymptotically AdS background in 4 spacetime dimensions, in the limit of a small cosmological constant or equivalently a large AdS radius $l$. This identifies $1/l^2$ perturbative corrections to the known asymptotically flat spacetime leading and subleading soft factors. Our analysis is only valid to leading order in $1/l^2$. The leading soft factor can be expected to be universal and holds beyond tree level. This allows us to derive a $1/l^2$ corrected Ward identity, following the known equivalence between large gauge Ward identities and soft theorems in asymptotically flat spacetimes.

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Nabamita Banerjee, Karan Fernandes, Arpita Mitra. 2021-02-11. Soft Photon theorem in the small negative cosmological constant limit. https://doi.org/10.1007/jhep08(2021)105

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