B Why do subatomic particles change what they do when observed?

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Subatomic particles exhibit a change in behavior upon observation due to the measurement problem in quantum mechanics, where a particle's state does not have a definite value until measured. This measurement causes the particle's state to collapse into a specific eigenstate related to the observable being measured. The identity of the observer, whether a sentient human or a non-sentient robot, does not affect the outcome of the measurement; it is the act of measurement itself that is crucial. Most measurements are conducted by devices, with humans interpreting the results rather than influencing the measurement process. Ultimately, the nature of observation in quantum mechanics remains a fundamental aspect of the theory.
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Measurement problem of quantum mechanics
Why do subatomic particles change what they do when observed? Does it matter who is doing the observing? What happens if a non-sentient robot does the observing? How does that compare with a sentient human doing the observing? Thank you.
 
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curiosity1 said:
Summary: Measurement problem of quantum mechanics

Why do subatomic particles change what they do when observed?
The dynamic quantity being measured does not have a definite value until a measurement is made.

After the measurement, the state of the particle "collapses" to an eigenstate of the observable that was measured.

That's essentially an axiom of QM. It's like a law of nature, so there is no more fundamental explanation.
curiosity1 said:
What happens if a non-sentient robot does the observing? How does that compare with a sentient human doing the observing? Thank you.
It makes no difference what makes the measurement. Most if not all, measurements are made by measurement devices and human beings only look at the output from those.
 
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Thank you very much for your quick and helpful reply.
 
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