I think I understand this only up to a point.(adsbygoogle = window.adsbygoogle || []).push({});

1. Photon spin is quantized to be +1 or -1 and these represent left- and right-hand circular polarization.

2. A photon can have a superposition of 2 spin states in any proportion.

3. Having probability amplitude of 0.5 of spin 1 and 0.5 of spin -1 yields linear polarization, and the orientation depends on the phase angle between the two.

4. Here is my question:

Suppose I let a photon with vertical linear polarization (obtained from a vertical linear polarizer) pass through another vertical linear polarizer. What is the transmission probability?

Classical reasoning says 1.0.

But if the photon can REALLY have only spin 1 or -1, the transmission probability is only 0.5 in either case and therefore 0.5 overall.

I suspect the problem is with the word 'really' because we are not allowed to ask about objective reality. But please explain and, if possible, without ket signs or matrices.

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# Photon spin and polarization

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