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arXiv · 1901.05223

Completely Positive Divisibility Does Not Mean Markovianity

Simon Milz·M. S. Kim·Felix A. Pollock·Kavan Modi
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Abstract

In the classical domain, it is well-known that divisibility does not imply that a stochastic process is Markovian. However, for quantum processes, divisibility is often considered to be synonymous with Markovianity. We show that completely positive (CP) divisible quantum processes can still involve non-Markovian temporal correlations, that we then fully classify using the recently developed process tensor formalism, which generalizes the theory of stochastic processes to the quantum domain.

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Simon Milz, M. S. Kim, Felix A. Pollock, Kavan Modi. 2019-01-16. Completely Positive Divisibility Does Not Mean Markovianity. https://doi.org/10.1103/physrevlett.123.040401

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