

A quantum effect you can observe with the naked eye - lcedp

http:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=-Yh-U8Ro-P0<p>I find it amazing.
You can repeat the experiment using lenses from polarized sun glasses with sun or computer monitor light.<p>Does anybody know of other examples?
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rom16384
Well one could argue the world is quantum, so that would give you lots of
examples! But more to the point:

* The colors you can see on a puddle of water with a bit of oil on it is due to interference [1]

* Certain butterflies wings colors are not due to pigments, but to microscopic structures that cause interference.

* One very striking example is superconductivity [2], where a material can conduct electricity without resistance, and expels magnetic fields, leading to magnetic levitation.

* Diamagnetism: Since water is slightly diamagnetic, that is, it creates a small magnetic field that oposes an external magnetic field applied to it, things with lots of water can be levitated in a strong enough magnetic field. [3]

[1] [http://www.kentshillphysics.net/light-optics/thin-films-
and-...](http://www.kentshillphysics.net/light-optics/thin-films-and-
interference/)

[2]
[https://www.youtube.com/watch?v=4HHJv8lPERQ](https://www.youtube.com/watch?v=4HHJv8lPERQ)

[3]
[http://www.ru.nl/hfml/research/levitation/diamagnetic/](http://www.ru.nl/hfml/research/levitation/diamagnetic/)

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andrewcooke
why can't this (three polarizers) be explained classically? googling turns up
this explanation, for example
[http://van.physics.illinois.edu/qa/listing.php?id=16544](http://van.physics.illinois.edu/qa/listing.php?id=16544)
or this one
[http://www.lhup.edu/~dsimanek/14/polaroid.htm](http://www.lhup.edu/~dsimanek/14/polaroid.htm)

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DavidPlumpton
Double slit experiment with a key ring laser. Liquid Helium.

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db48x
Fluorescent lightbulbs, you may have seen one.

