
Measuring up to Heisenberg (and since) - ColinWright
http://robjlow.blogspot.com/2017/12/measuring-up-to-heisenberg-and-since.html
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QAPereo
Are people really that confused about the difference between fundamental
natural uncertainty, and the measurement problem?

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antonvs
Are you referring to the first paragraph of the article, or something else?
The first paragraph describes the observer effect, not the measurement problem
or the uncertainty principle. The observer effect is indeed often confused
with the uncertainty principle.

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wadkar
I thought the act of observation was what caused the uncertainty. But it
appears to me that you’re saying that may not be the case. Could you please
enlighten me? What causes the uncertainty if not the act of measurement
(observation?) Do the two terms, observation and measurement have different
meaning? Could you please explain me the difference? Thanks much!

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marcosdumay
Fundamental uncertainty is indeed caused by different observations
"interfering with each other. And that interference is only inevitable because
of the observer effect.

It's kind of meaningless to claim that observation is the cause of the
uncertainty, but I do think you are on the right path. Still, even being
related, the observer effect and the fundamental uncertainty are different
concepts. For example, observations may not interfere at all, but they would
still change your system.

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akvadrako
Fundamental uncertainty has nothing to do with observations - it's inherit in
the physical/mathematical representation of a state as explained by the
comment above yours.

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marcosdumay
Hum... Uncertainty is not about states, it is about observables.

It is a characteristic of the Universe that you can't measure momentum and
position with perfect accuracy, it does not matter what state the stuff you
are measuring is in. And it happens because observing momentum messes with the
objects position, and the other way around.

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akvadrako
Another way to say it is there is no state with accurate position and
momentum.

