  Understanding static and dynamic phenomena in complex materials at different
length scales requires reliably accounting for van der Waals (vdW)
interactions, which stem from long-range electronic correlations. While the
important role of many-body vdW interactions has been extensively documented
when it comes to the stability of materials, much less is known about the
coupling between vdW interactions and atomic forces. Here we analyze the
Hessian force response matrix for a single and two vdW-coupled atomic chains to
show that a many-body description of vdW interactions yields atomic force
response magnitudes that exceed the expected pairwise decay by 3-5 orders of
magnitude for a wide range of separations between the perturbed and the
observed atom. Similar findings are confirmed for graphene and carbon
nanotubes. This colossal force enhancement suggests implications for phonon
spectra, free energies, interfacial adhesion, and collective dynamics in
materials with many interacting atoms.
