Classical Double Copy and Higher-Spin Fields.

Abstract

Kerr-Schild double copy is shown to extend naturally to all free symmetric gauge fields propagating on (A)dS in any dimension. Similarly to the standard lower-spin case, the higher-spin multicopy comes along with the zeroth, single, and double copies. The masslike term of the Fronsdal spin s field equations fixed by gauge symmetry and the mass of the zeroth copy both appear to be remarkably fine-tuned to fit the multicopy pattern forming a spectrum organized by higher-spin symmetry. On the black hole side this curious observation fills up the list of miraculous properties of the Kerr solution.