  We discuss a quantitative "double copy" between radiation from shockwave
collisions in Einstein gravity and in QCD. The correspondence extends to
$2\rightarrow N$ amplitudes in Regge asymptotics. The classicalization and
unitarization of these amplitudes at maximal occupancy, corresponding to black
hole and Color Glass Condensate (CGC) states respectively, are described by the
emergent Goldstone dynamics of wee partons. We outline some consequences of the
universal dynamics on both sides of the correspondence.
