Computational tameness of classical non-causal models

@article{Baumeler2018ComputationalTO,
  title={Computational tameness of classical non-causal models},
  author={{\"A}min Baumeler and Stefan Wolf},
  journal={Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences},
  year={2018},
  volume={474}
}
  • Ämin Baumeler, S. Wolf
  • Published 17 November 2016
  • Computer Science
  • Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences
We show that the computational power of the non-causal circuit model, i.e. the circuit model where the assumption of a global causal order is replaced by the assumption of logical consistency, is completely characterized by the complexity class UP∩coUP. An example of a problem in that class is factorization. Our result implies that classical deterministic closed timelike curves (CTCs) cannot efficiently solve problems that lie outside of that class. Thus, in stark contrast to other CTC models… 
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