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arXiv · 1712.04551

BMS Supertranslation Symmetry Implies Faddeev-Kulish Amplitudes

Sangmin Choi·Ratindranath Akhoury
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Abstract

We show explicitly that, among the scattering amplitudes constructed from eigenstates of the BMS supertranslation charge, the ones that conserve this charge, are equal to those constructed from Faddeev-Kulish states. Thus, Faddeev-Kulish states naturally arise as a consequence of the asymptotic symmetries of perturbative gravity and all charge conserving amplitudes are infrared finite. In the process we show an important feature of the Faddeev-Kulish clouds dressing the external hard particles: these clouds can be moved from the incoming states to the outgoing ones, and vice-versa, without changing the infrared finiteness properties of S matrix elements. We also apply our discussion to the problem of the decoherence of momentum configurations of hard particles due to soft boson effects.

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Sangmin Choi, Ratindranath Akhoury. 2017-12-12. BMS Supertranslation Symmetry Implies Faddeev-Kulish Amplitudes. https://doi.org/10.1007/jhep02(2018)171

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