In
quantum Darwinism
Quantum Darwinism is a theory meant to explain the emergence of the classical world from the quantum world as due to a process of Darwinian natural selection induced by the environment interacting with the quantum system; where the many possible ...
and similar theories, pointer states are
quantum state
In quantum physics, a quantum state is a mathematical entity that provides a probability distribution for the outcomes of each possible measurement on a system. Knowledge of the quantum state together with the rules for the system's evolution in ...
s, sometimes of a measuring apparatus, if present, that are less perturbed by
decoherence
Quantum decoherence is the loss of Coherence (physics)#Quantum coherence, quantum coherence. In quantum mechanics, particles such as electrons are described by a wave function, a mathematical representation of the quantum state of a system; a p ...
than other states, and are the quantum equivalents of the classical states of the system after decoherence has occurred through interaction with the environment.
'Pointer' refers to the reading of a recording or measuring device, which in old analog versions would often have a
gauge
Gauge ( or ) may refer to:
Measurement
* Gauge (instrument), any of a variety of measuring instruments
* Gauge (firearms)
* Wire gauge, a measure of the size of a wire
** American wire gauge, a common measure of nonferrous wire diameter, es ...
or pointer display.
See also
*
Einselection
In quantum mechanics, einselections, short for "environment-induced superselection", is a name coined by Wojciech H. Zurek
for a process which is claimed to explain the appearance of wavefunction collapse and the emergence of classical descript ...
*
Mott problem
In quantum mechanics, the Mott problem is a paradox that illustrates some of the difficulties of understanding the nature of wave function collapse and measurement in quantum mechanics. The problem was first formulated in 1929 by Sir Nevill Fran ...
References
Quantum mechanics
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