The Observer effect and Wikipedia (Spin Off )

[studiot]

This thread is inspired by confusion in another thread which may be due to a Wikipedia article, I consder misleading and muddled, about the observer effect,

https://www.scienceforums.net/topic/116760-observer-effect-and-uncertainty-principle-are-the-same/

although I would say it has relevence to several other current threads as well.

 

Quote

Wikipedia

In physics, the observer effect is the theory that simply observing a situation or phenomenon necessarily changes that phenomenon. This is often the result of instruments that, by necessity, alter the state of what they measure in some manner. ..........

..................... An especially unusual version of the observer effect occurs in quantum mechanics, ..............................................................

.................its results have led to the popular belief that a conscious mind can directly affect reality............................................

 

https://en.wikipedia.org/wiki/Observer_effect_(physics)

 

Now I think it is good to separate out errors of measurement due to the conditions of observation from the errrors that are inherent in the nature of that which is being observed.

But I also think that Wikipedia is wrong to suggest that there are no methods of measurement that are theoretically error free or that quantum effects should be attributed to the observer.

Note this thread is about the origin and details of any effects attributable to the observer;
It is not about the origin and details of effects due to the measureand, except where the affect the former.

Comments invited.

 

 

Edited March 13, 2019 by studiot

[Eise]

I think one should read the Wikipedia page carefully. There might be many examples of an observer effect in QM, but the HUP isn't one of them, as the article itself clearly states:

Quote

The uncertainty principle has been frequently confused with the observer effect, evidently even by its originator, Werner Heisenberg. The uncertainty principle in its standard form describes how precisely we may measure the position and momentum of a particle at the same time – if we increase the precision in measuring one quantity, we are forced to lose precision in measuring the other.

 

[studiot]

5 minutes ago, Eise said:

I think one should read the Wikipedia page carefully. There might be many examples of an observer effect in QM, but the HUP isn't one of them, as the article itself clearly states:

 

But some parts are just plain old fashioned wrong and some parts give the wrong impression because they are not specific.

Why, for instance pick out QM, which has a well publicised 'Uncertainty Principle' ?

So yes, read it carefully skeptically, then burn after reading, Ethan Hunt.

Edited March 13, 2019 by studiot

[Carrock]

4 hours ago, studiot said:

But I also think that Wikipedia is wrong to suggest that there are no methods of measurement that are theoretically error free or that quantum effects should be attributed to the observer.

Confusing Wikipedia article at best.

I read it as

Quote

I think that Wikipedia is wrong to suggest that there are methods of measurement that are theoretically error free and correct that quantum effects should not be attributed to the observer.

From Wikipedia

Quote

In particular, a measurement of momentum is non-repeatable in short intervals of time.

The clear implication (in context) is that momentum is unchanged if you take a longer time. Contradicted by the equation a few lines later.

 

Just working out what the author means is an effort and I'm not sure which of us got the meaning right.

 

[Strange]

5 hours ago, studiot said:

But I also think that Wikipedia is wrong to suggest that there are no methods of measurement that are theoretically error free

I can't see where it suggests that.

5 hours ago, studiot said:

or that quantum effects should be attributed to the observer.

It explicitly says that they are not.