I have a fundamental question regarding the uncertainty principle (position and momentum). This principle states that it is impossible simultaneously to(adsbygoogle = window.adsbygoogle || []).push({}); knowboth position and momentum with arbitrarily good precision - even in principle.

Now, what does "know" mean? No one can prevent you from doing a simultaneous measurement on position and momentum, and the values you get must be the position and momentum at the time of measurement (within the accuracy of the apparatus, which - in principle - can be made as small as you like). The position and momentum becomes well-defined when measured.

By my understanding the only thing that the uncertainty principle says is that if we performidenticalexperiments and we get a small spread in x-values we will get a large spread in p-values according to [tex] \Delta x \Delta p_x \geq \bar{h} [/tex]. [tex]\Delta x[/tex] should be interpreted as the standard deviation in the measured x-values and [tex]\Delta p_x[/tex] as the standard deviation in the measured p-values.

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# Interpretation of the uncertainty principle

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