Noncausal Page-Wootters circuits

@article{Baumann2022NoncausalPC,
  title={Noncausal Page-Wootters circuits},
  author={Veronika Baumann and Marius Krumm and Philippe Allard Gu{\'e}rin and vCaslav Brukner},
  journal={Physical Review Research},
  year={2022}
}
Veronika Baumann, 2, 3, ∗ Marius Krumm, 2, ∗ Philippe Allard Guérin, 2, 4 and Časlav Brukner 2 Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria Institute for Quantum Optics and Quantum Information (IQOQI), Austrian Academy of Sciences, Boltzmanngasse 3, 1090 Vienna, Austria Faculty of Informatics, Università della Svizzera italiana, Via G. Buffi 13, CH-6900 Lugano, Switzerland Perimeter Institute for Theoretical Physics, 31 Caroline St. N, Waterloo, Ontario, N2L… 
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