All Order Classical Electromagnetic Soft Theorems

Debanjan Karan; Babli Khatun; Biswajit Sahoo; Ashoke Sen

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arXiv · 2501.07328

All Order Classical Electromagnetic Soft Theorems

Debanjan Karan·Babli Khatun·Biswajit Sahoo·Ashoke Sen

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Abstract

If a set of charged objects collide in space and the fragments disperse, then this process will emit electromagnetic waves. Classical soft photon theorem determines the constant term and the leading power law fall-off of the wave-form at late and early times in terms of only the momenta and charges of the incoming and outgoing objects. In this paper we determine an infinite set of subleading terms in the late and early time expansion of the wave-form, which also depend only on the momenta and charges of the incoming and outgoing particles. For two-particle scattering, we derive a resummed low-frequency electromagnetic wave-form, as well as the resummed wave-form at early and late times. In this analysis we ignore the effect of long range gravitational interaction, but our result is unaffected by any other short range interactions among the objects.

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Debanjan Karan, Babli Khatun, Biswajit Sahoo, Ashoke Sen. 2025-01-13. All Order Classical Electromagnetic Soft Theorems. https://arxiv.org/abs/2501.07328

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