Completely Positive Divisibility Does Not Mean Markovianity
arXiv:1901.05223 · doi:10.1103/PhysRevLett.123.040401
The paper demonstrates that quantum processes which are completely positive (CP) divisible can still exhibit non‑Markovian temporal correlations, and provides a classification of such processes using the process tensor formalism.
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.
4+5 pages, 4 figures, close to published version