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apeiron
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One of the curiosities of 20th century physics was that the complementarity principle was central to the QM revolution, yet physics only took heed of uncertainty. Why?
Kote would certainly have an opinion. But here are some relevant snippets to remind others.
Niels Bohr on the importance and universality of complementarity or conjugate pairs...
[So it was not just about QM but a general philosophical fact - profound truths come in opposing pairs.]
[The familiar statement of particle~wave and location~momentum duality.]
[Now we can see that the dualities are not states but limits. So it is not a case of either/or when it comes to a question like is it looking like a wave or a particle? Instead it is about the separation towards limits, in which an electron becomes increasingly particle-like as it becomes increasingly less wave-like.]
[Again, what is fundamental is not a binary division that just exist, but instead the separation of a particle's potential in one or other possible direction.]
[Again the social perspective. Bohr thought he was on to something fundamental. But the physics community didn't want to go there.]
Kote would certainly have an opinion. But here are some relevant snippets to remind others.
Niels Bohr on the importance and universality of complementarity or conjugate pairs...
One of his favorite maxims was that there are two types of truths: trivial truths whose opposites are plainly absurd, and profound truths which can be recognized by the fact that the opposite is also a profound truth.
[So it was not just about QM but a general philosophical fact - profound truths come in opposing pairs.]
We can think of electrons as both a particle or a wave or stream of particles depending on the situation. An object being a particle AND a wave is seemingly mutually exclusive and not possible. But an electron, in some sense, is both at once.
A profound aspect of complementarity is that it not only applies to measurability or knowability of some property of a physical entity, but more importantly it applies to the limitations of that physical entity’s very manifestation of the property in the physical world. All properties of physical entities exist only in pairs, which Bohr described as complementary or conjugate pairs.
http://en.wikipedia.org/wiki/Complementarity_(physics )
[The familiar statement of particle~wave and location~momentum duality.]
An electron can manifest a greater and greater accuracy of its position only in even trade for a complementary loss in accuracy of manifesting its momentum. This means that there is a limitation on the precision with which an electron can possesses (i.e., manifest) position, since an infinitely precise position would dictate that its manifested momentum would be infinitely imprecise, or undefined (i.e., non-manifest or not possessed), which is not possible.
[Now we can see that the dualities are not states but limits. So it is not a case of either/or when it comes to a question like is it looking like a wave or a particle? Instead it is about the separation towards limits, in which an electron becomes increasingly particle-like as it becomes increasingly less wave-like.]
Both behaviors can be observed at the same time, but each only as lesser manifestations of their full behavior (as determined by the duality relation). This superposition of complementary behaviors exists whenever there is partial "which slit" information...
...a stronger manifestation of the particle nature leads to a weaker manifestation of the wave nature and vice versa.
[Again, what is fundamental is not a binary division that just exist, but instead the separation of a particle's potential in one or other possible direction.]
The group surrounding Bohr soon came to perceive complementarity and uncertainty as so closely intertwined that in 1928 Heisenberg gave Bohr's concept precedence over his own...In the larger physics community, however, the uncertainty principle became inseparable from any presentation of quantum mechanics, while complementarity figured little in the teaching of the new physics. It tended to be regarded as overly philosophical, vague, and irrelevant.
In recompense, complementarity took on a life beyond physics. Bohr sought to generalize its application, first to psychology, then to biology, and ultimately beyond the scope of natural science. Although he did not complete the book on the topic that he had hoped to write, Bohr conceived complementarity as a general epistemological argument of great import for humanity.
http://science.jrank.org/pages/48960/complementarity-uncertainty.html
[Again the social perspective. Bohr thought he was on to something fundamental. But the physics community didn't want to go there.]
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