# The Multi-round Process Matrix

@article{Hoffreumon2021TheMP, title={The Multi-round Process Matrix}, author={Timoth'ee Hoffreumon and O. Oreshkov}, journal={Quantum}, year={2021}, volume={5}, pages={384} }

We develop an extension of the process matrix (PM) framework for correlations between quantum operations with no causal order that allows multiple rounds of information exchange for each party compatibly with the assumption of well-defined causal order of events locally. We characterise the higher-order process describing such correlations, which we name the multi-round process matrix (MPM), and formulate a notion of causal nonseparability for it that extends the one for standard PMs. We show… Expand

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