Why do subatomic particles change what they do when observed?

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Discussion Overview

The discussion revolves around the measurement problem in quantum mechanics, specifically addressing why subatomic particles appear to change their behavior when observed. Participants explore the implications of different observers, including sentient humans versus non-sentient robots, on the measurement process and the nature of quantum states.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions why subatomic particles change behavior upon observation and whether the observer's nature (sentient vs. non-sentient) affects this change.
  • Another participant summarizes the measurement problem, stating that a dynamic quantity does not have a definite value until measured, leading to a "collapse" of the particle's state to an eigenstate of the observable.
  • This participant asserts that the act of measurement is an axiom of quantum mechanics, likening it to a law of nature without a more fundamental explanation.
  • It is proposed that the identity of the observer does not matter, as measurements are typically made by devices, with humans merely interpreting the output.

Areas of Agreement / Disagreement

Participants express differing views on the implications of the observer's identity in the measurement process, indicating that the discussion remains unresolved regarding the significance of who or what is observing.

Contextual Notes

There are limitations in the discussion regarding assumptions about measurement and the definitions of observers, which remain unresolved.

curiosity1
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TL;DR
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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