  Recent attempts at the construction of holography for asymptotically flat
spacetimes have taken two different routes. Celestial holography, involving a
two dimensional (2d) CFT dual to 4d Minkowski spacetime, has generated novel
results in asymptotic symmetry and scattering amplitudes. A different
formulation, using Carrollian CFTs, has been principally used to provide some
evidence for flat holography in lower dimensions. Understanding of flatspace
scattering has been lacking in the Carroll framework. In this work, using ideas
from Celestial holography, we show that 3d Carrollian CFTs living on the null
boundary of 4d flatspace can potentially compute bulk scattering amplitudes. 3d
Carrollian conformal correlators have two different branches, one depending on
the null time direction and one independent of it. We propose that it is the
time-dependent branch that is related to bulk scattering. We construct an
explicit field theoretic example of a free massless Carrollian scalar that
realises some desired properties.
