6d (2, 0) and M-theory at 1-loop

We study the stress tensor multiplet four-point function in 6d maximally supersymmetric $(2,0)$ $A_{N-1}$ and $D_N$ theories, which have no Lagrangian description, but large $N$ limit are holographically dual to weakly coupled M-theory on $AdS_7\times S^4$ S^4/\mathbb{Z}_2$, respectively. use analytic bootstrap compute 1-loop correction this holographic correlator coming from Witten diagrams with supergravity $R$ first higher derivative $R^4$ vertices, is computed for a non-Lagrangian theory. then take flat space find precise agreement corresponding terms 11d S-matrix, some of we time using two-particle unitarity cuts.