Quantum Darwinism

One of the stranger aspects of the Quantum World is the ability of a Quantum system to exist on more than one state at the same time. The system collapses into one state the moment we observe it. This is called decoherence and Quantum Darwinism is an attempt to explain it.

Rather than our observation being the thing that forces the Quantum System to collapse into one state, Quantum Darwinism suggests that it is the system's interactions with the environment causing the decoherence. Macro objects are always subjected to environmental factors and that's why we don't see them in the Quantum state.

As far how the environment has this effect, according to Zurek's theory, Quantum Systems have "pointer states". These are special measurable characteristics such as particle location or speed.

When a particle interacts with the environment, all the super positions of those characteristics- alternate locations or speeds-decohere,leaving just the pointer state which many people can observe because it "imprints" replicas of itself on the environment and only the "fittest" state- the one best suited for its particular environment- survives the process of decoherence.