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If a photon has polarization.



Dear friends

I have some questions about the polarization of light. From classical Mexwell
Equation, one can give out a electromagnetic wave with polarization. And visible
lights has polarization as well. However, one can not say that a photon has polarization.

Spin is the property of photon to substitute polariztion in the field theory.
However, I still cannot understand why visible lights has polarization, but a visible
photon has not.

Let's think out a ideal experiment:
There are three tubes, each one has a film in its bottum. Two of these tube have

polarization foils (PF). I mark them 2 and 3. The polarization foils in 2 tube
are parallel, while the polarization foils in 3 tube are vertical. 'Parallel' means
the parallel of polarization, the same of 'vertical'.



----------------------------------|
| 1
----------------------------------|

film

--------|----------------|--------|
| | | 2
--------|----------------|--------|

| | film


--------|----------------|--------|
| | | 3
--------|----------------|--------|

| \ film

They are put into a dark room, i.e. a vacuum of lights. However it is not absolute
vacuum of lights. After a week, there may be a photon enters a tube and reach the film
in tube 1. The question is that, after several monthes, can some photon reach the
film in 2 and 3 tubes?