  Understanding strongly correlated quantum many-body states is one of the most
difficult challenges in modern physics. For example, there remain fundamental
open questions on the phase diagram of the Hubbard model, which describes
strongly correlated electrons in solids. In this work we realize the Hubbard
Hamiltonian and search for specific patterns within the individual images of
many realizations of strongly correlated ultracold fermions in an optical
lattice. Upon doping a cold-atom antiferromagnet we find consistency with
geometric strings, entities that may explain the relationship between hole
motion and spin order, in both pattern-based and conventional observables. Our
results demonstrate the potential for pattern recognition to provide key
insights into cold-atom quantum many-body systems.
