Non-Markovianity hinders Quantum Darwinism.

Fernando Galve,Sabrina Maniscalco,Roberta Zambrini

doi:10.1038/srep19607

Abstract

We investigate Quantum Darwinism and the emergence of a classical world from the quantum one in connection with the spectral properties of the environment. We use a microscopic model of quantum environment in which, by changing a simple system parameter, we can modify the information back flow from environment into the system, and therefore its non-Markovian character. We show that the presence of memory effects hinders the emergence of classical objective reality, linking these two apparently unrelated concepts via a unique dynamical feature related to decoherence factors.

Highlights

We investigate Quantum Darwinism and the emergence of a classical world from the quantum one in connection with the spectral properties of the environment
We have studied the connection between non-Markovian dynamics, characterized by information flow back, and the emergence of an objective classical reality through the proliferation of classical copies of the system state in the normal modes of the environment
By modifying the properties of the spectral density, and, in particular, by changing the resonance condition between the system oscillator and the reservoir spectrum, we can inhibit quantum Darwinism by modifying the Markovian character of the dynamical map

Summary

Introduction

We investigate Quantum Darwinism and the emergence of a classical world from the quantum one in connection with the spectral properties of the environment. A recent breakthrough in the field[2] has shown that spreading of the classical information about a pointer observable into the environment is a generic feature of quantum mechanics They show that a generic quantum evolution of system plus a large environment results in a measure and prepare map for fractions in the environment, that is, only information about measurement outcomes of a particular POVM are scattered around and proliferate. Fulfilment of Quantum Darwinism, in which very small fragments of the environment are fully informative, is a peculiarity of the physical interactions that we have in nature This latter peculiarity, that close to full information about the system pointer is redundantly copied among many small fragments in the surroundings, has been recently shown for all models of pure decoherence[8], for the photonic environment[9,10,11], and in general for a two level system under a (environment symmetric) controlled unitary evolution for the bath[12]. Experimental evidence for its workings in a quantum dot scenario has been given in[13]

Methods

Results

Conclusion