  Renormalization group ideas and effective operators are used to efficiently
determine localized unitaries for preparing the ground states of
non-interacting scalar field theories on digital quantum devices. With these
methods, classically computed ground states in a small spatial volume can be
used to determine operators for preparing the ground state in a
beyond-classical quantum register, even for interacting scalar field theories.
Due to the exponential decay of correlation functions and the double
exponential suppression of digitization artifacts, the derived quantum circuits
are expected to be relevant already for near-term quantum devices.
