Undergrad Quantum decoherence vs. measurement process

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Decoherence time is very short for macroscopic objects like detectors, but it does not explain why quantum measurements yield single outcomes. Instead, decoherence accounts for the lack of interference between potential outcomes. The influence of a measurement on the detection system is crucial; for instance, a detector that captures a photon without disturbing its spin does not induce decoherence in that spin. Once a measurement is made and recorded, the state becomes committed and can be viewed as decohered. Understanding the relationship between decoherence and measurement outcomes remains a complex topic in quantum mechanics.
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The decoherence time is extremely short for macroscopic objects like a detector. Does this mean that the outcome of a quantum measurement which happens instantaneous can be understood as being caused by decoherence?
 
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timmdeeg said:
The decoherence time is extremely short for macroscopic objects like a detector. Does this mean that the outcome of a quantum measurement which happens instantaneous can be understood as being caused by decoherence?
No, because decoherence does not explain why measurements have single outcomes. It only explains why there is no interference between different outcomes.
 
timmdeeg said:
The decoherence time is extremely short for macroscopic objects like a detector. Does this mean that the outcome of a quantum measurement which happens instantaneous can be understood as being caused by decoherence?
The detector may be large, but what is important is how much influence a measurement has on the state of the detection system. A detector that captures a photon or other particle without disturbing its spin would not result in decoherence of the spin. Once a measurement has resulted in the movement of a dial or the recording or transmission of measurement data, that measured state is committed - it can be "understood" as decohered.
 
Thanks to both of you for clarifying my question.
 

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