English

Restoring broken symmetries using oracles

Quantum Physics 2022-10-21 v1 Strongly Correlated Electrons Nuclear Theory

Abstract

We present a new method to perform variation after projection in many-body systems on quantum computers that does not require performing explicit projection. The technique employs the notion of ``oracle'', generally used in quantum search algorithms. We show how to construct the oracle and the projector associated with a symmetry operator. The procedure is illustrated for the parity, particle number, and total spin symmetries. The oracle is used to restore symmetry by indirect measurements using a single ancillary qubit. An Illustration of the technique is made to obtain the approximate ground state energy for the pairing model Hamiltonian.

Keywords

Cite

@article{arxiv.2210.11181,
  title  = {Restoring broken symmetries using oracles},
  author = {Edgar Andres Ruiz Guzman and Denis Lacroix},
  journal= {arXiv preprint arXiv:2210.11181},
  year   = {2022}
}
R2 v1 2026-06-28T04:04:38.261Z