“where you cannot divorce the property you are trying to measure from the type of observation you make: the property is dependent on the measurement.” “W. H. Zurek and colleagues introduced the “environment as witness ” formulation of de-coherence [15, 16] in recognition of the fact that observers typically obtain pointer-state information about quantum systems by interacting with the surrounding environment, e.g. **the ambient photon field**. In this formulation and its “quantum Darwinist” extension to multiple observers [17, 18, 19, 20, 21], the environment is taken to encode pointer-state information for quantum systems embedded in it in a way that is massively redundant and hence equally accessible to many non-interacting observers. Other than interaction with the environment, no physical restrictions are placed on the ob servers in this picture; in particular, they are not restricted in either their location with respect to the observed system(s) or the resolution with which they interact with the environment. The resolution with which the environment encodes pointer-state information about any particular object is similarly unrestricted by any a priori consideration.”

“where you cannot divorce the property you are trying to measure from the type of observation you make: the property is dependent on the measurement.”

“W. H. Zurek and colleagues introduced the “environment as witness ” formulation of de-coherence [15, 16] in recognition of the fact that observers typically obtain pointer-state information about quantum systems by interacting with the surrounding environment, e.g. **the ambient photon field**. In this formulation and its “quantum Darwinist” extension to multiple observers [17, 18, 19, 20, 21], the environment is taken to encode pointer-state information for quantum systems embedded in it in a way that is massively redundant and hence equally accessible to many non-interacting observers. Other than interaction with the environment, no physical restrictions are placed on the ob servers in this picture; in particular, they are not restricted in either their location with respect to the observed system(s) or the resolution with which they interact with the environment. The resolution with which the environment encodes pointer-state information about any particular object is similarly unrestricted by any a priori consideration.”