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arXiv · 1705.06175

Double-soft behavior of the dilaton of spontaneously broken conformal invariance

Paolo Di Vecchia·Raffaele Marotta·Matin Mojaza
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Abstract

The Ward identities involving the currents associated to the spontaneously broken scale and special conformal transformations are derived and used to determine, through linear order in the two soft-dilaton momenta, the double-soft behavior of scattering amplitudes involving two soft dilatons and any number of other particles. It turns out that the double-soft behavior is equivalent to performing two single-soft limits one after the other. We confirm the new double-soft theorem perturbatively at tree-level in a $D$-dimensional conformal field theory model, as well as nonperturbatively by using the "gravity dual'' of ${\cal{N}}=4$ super Yang-Mills on the Coulomb branch; i.e. the Dirac-Born-Infeld action on AdS${}_5 \times S^5$.

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Paolo Di Vecchia, Raffaele Marotta, Matin Mojaza. 2017-05-17. Double-soft behavior of the dilaton of spontaneously broken conformal invariance. https://doi.org/10.1007/jhep09(2017)001

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