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arXiv · 1212.2648

Universality of Computation in Real Quantum Theory

Alessio Belenchia·Giacomo Mauro D'Ariano·Paolo Perinotti
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Abstract

Recently de La Torre et al. [1] reconstructed Quantum Theory from its local structure on the basis of local discriminability and the existence of a one-parameter group of bipartite transformations containing an entangling gate. This result relies on universality of an entangling gate for quantum computation. Here we prove universality of C-NOT with local gates for Real Quantum Theory (RQT), showing that such universality would not be sufficient for the result, whereas local discriminability and the qubit structure play a crucial role. For reversible computation, generally an extra rebit is needed for RQT. As a byproduct we also provide a short proof of universality of C-NOT for CQT.

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Alessio Belenchia, Giacomo Mauro D'Ariano, Paolo Perinotti. 2012-12-11. Universality of Computation in Real Quantum Theory. https://doi.org/10.1209/0295-5075%2F104%2F20006

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