  We experimentally investigate the quantum motion of an impurity atom that is
immersed in a strongly interacting one-dimensional Bose liquid and is subject
to an external force. We find that the momentum distribution of the impurity
exhibits characteristic Bragg reflections at the edge of an emergent Brillouin
zone. While Bragg reflections are typically associated with lattice structures,
in our strongly correlated quantum liquid they result from the interplay of
short-range crystalline order and kinematic constraints on the many-body
scattering processes in the one-dimensional system. As a consequence, the
impurity exhibits periodic dynamics that we interpret as Bloch oscillations,
which arise even though the quantum liquid is translationally invariant. Our
observations are supported by large-scale numerical simulations.
