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

curiosity1
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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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