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arXiv · 1801.05528

Infinite Set of Soft Theorems in Gauge-Gravity Theories as Ward-Takahashi Identities

Yuta Hamada·Gary Shiu
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Abstract

We show that the soft photon, gluon and graviton theorems can be understood as the Ward-Takahashi identities of large gauge transformation, i.e., diffeomorphism that does not fall off at spatial infinity. We found infinitely many new identities which constrain the higher order soft behavior of the gauge bosons and gravitons in scattering amplitudes of gauge and gravity theories. Diagrammatic representations of these soft theorems are presented.

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Yuta Hamada, Gary Shiu. 2018-01-17. Infinite Set of Soft Theorems in Gauge-Gravity Theories as Ward-Takahashi Identities. https://doi.org/10.1103/physrevlett.120.201601

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