Redundant imprinting of information in non-ideal environments: Quantum Darwinism via a noisy channel

Quantum Darwinism provides an information-theoretic framework for the emergence of the classical world from the quantum substrate. It recognizes that we - the observers - acquire our information about the ``systems of interest'' indirectly from their imprints on the environment. Objectivity, a key property of the classical world, arises via the proliferation of redundant information into the environment where many observers can then intercept it and independently determine the state of the system. While causing a system to decohere, environments that remain nearly invariant under the Hamiltonian dynamics, such as very mixed states, have a diminished ability to transmit information about the system, yet can still acquire redundant information about the system [1,2]. Our results show that Quantum Darwinism is robust with respect to non-ideal initial states of the environment.\\[4pt] [1] M. Z., H. T. Q., W. H. Z., Phys. Rev. Lett. 103, 110402 (2009)\\[0pt] [2] M. Z., H. T. Q., W. H. Z., Phys. Rev. A 81, 062110 (2010)