  We propose studying a new representation of on-shell Anti de Sitter (AdS)
amplitude in Mellin Momentum space, where it encodes all the dynamical
information in Cosmological Correlators. At tree level, we demonstrate that
this amplitude has a similar analytic structure as the S-matrix, with residues
of poles made up of on-shell lower-point amplitudes. We use this structure to
bootstrap 4-point scalar amplitudes with spin-1 and spin-2 exchange. In the
second part of the paper, we use double copy to construct the 4-point graviton
amplitude in general dimension. This leads us to a novel, concise formula that
exhibits the flat space structure. We also verified this formula for the case
when d=3 with literature.
