  We simulate the dynamics of Rydberg atoms resonantly exchanging energy via
two-, three-, and four-body dipole-dipole interactions in a one-dimensional
array. Using simplified models of a realistic experimental system, we study the
initial state survival probability, mean level spacing, spread of entanglement,
and properties of the energy eigenstates. By exploring a range of disorders and
interaction strengths, we find regions in parameter space where the three- and
four-body dynamics either fail to thermalize or do so slowly. The interplay
between the stronger hopping and weaker field-tuned interactions gives rise to
quantum many-body scar states, which play a critical role in slowing the
dynamics of the three- and four-body interactions.
