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advanced_notions:uncertainty_principle [2018/05/18 07:30]
77.10.73.75 [Why is it interesting?]
advanced_notions:uncertainty_principle [2018/07/26 17:56] (current)
77.177.199.249 [FAQ]
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 <​cite>​https://​www.scientificamerican.com/​article/​common-interpretation-of-heisenbergs-uncertainty-principle-is-proven-false/</​cite>​ <​cite>​https://​www.scientificamerican.com/​article/​common-interpretation-of-heisenbergs-uncertainty-principle-is-proven-false/</​cite>​
 </​blockquote>​ </​blockquote>​
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 +<​blockquote>​Bohr,​ for his part, explained uncertainty by pointing out that answering certain questions necessitates not answering others. To measure position, we need a stationary measuring object, like a fixed photographic plate. This plate defines a fixed frame of reference. To measure velocity, by contrast, we need an apparatus that allows for some recoil, and hence moveable parts. This experiment requires a movable frame. Testing one therefore means not testing the other. <​cite>​https://​opinionator.blogs.nytimes.com/​2013/​07/​21/​nothing-to-see-here-demoting-the-uncertainty-principle/</​cite></​blockquote>​
  
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 \begin{equation} ​ \sigma_A \sigma_B \geq \big | \frac{1}{2i} \langle [A,B] \rangle \big|^2 . \end{equation} \begin{equation} ​ \sigma_A \sigma_B \geq \big | \frac{1}{2i} \langle [A,B] \rangle \big|^2 . \end{equation}
  
 +See also
 +
 +  * [[https://​arxiv.org/​abs/​quant-ph/​0608138|The certainty principle (review)]] by D. A. Arbatsky
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 <tabbox FAQ> ​ <tabbox FAQ> ​
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 --> Is there a time-energy uncertainty relation?# --> Is there a time-energy uncertainty relation?#
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---->​What'​s the origin of the uncertainty?​ #+-->​What'​s the origin of the uncertainty?#​
  
 <​blockquote>​Quantum mechanics uses the generators of the corresponding symmetry as measurement operators. For instance, this has the consequence that a measurement of momentum is equivalent to the action of the translation generator. (Recall that invariance under translations leads us to conservation of momentum.) The translation generator moves our system a little bit and therefore the location is changed.<​cite>​Physics from Symmetry by J. Schwichtenberg</​cite></​blockquote>​ <​blockquote>​Quantum mechanics uses the generators of the corresponding symmetry as measurement operators. For instance, this has the consequence that a measurement of momentum is equivalent to the action of the translation generator. (Recall that invariance under translations leads us to conservation of momentum.) The translation generator moves our system a little bit and therefore the location is changed.<​cite>​Physics from Symmetry by J. Schwichtenberg</​cite></​blockquote>​
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advanced_notions/uncertainty_principle.1526621425.txt.gz · Last modified: 2018/05/18 05:30 (external edit)