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by mygo 2550 days ago
> Objects also have other internal (non-space/position) related properties. For example, light has polarization.

So the angular momentum of light would be put under the same category as polarization, which is a property that a single photon can have?

Or is it a property like wavelength, momentum, frequency, intensity, etc -- a property of light that can be observed only when the light is a system of lots of photons, instead of just an individual photon?

Also, sorry if my categories are wrong. If so, I hope it doesn't take away from my main question of whether it is a property of a single photon or a property of a system of photons

2 comments

Every category you have named, wavelength/frequency, intensity (function of frequency), linear momentum (function of frequency), polarization are properties that individual photons have. It is possible to construct photon detectors that are able to resolve these properties for a single photon thrown at them.

Orbital angular momentum is also a property of single photons, related to the shape of their wave function. You can read about it and see some example shapes on the wikipedia page https://en.wikipedia.org/wiki/Orbital_angular_momentum_of_li...

I can't think of a property of light that is only in the bulk and not at the single photon level (somebody correct me if I am wrong). But I haven't read this paper in any detail to find if the "torque" is a bulk property or a single photon property.

Wavelength = 1 / frequently and is directly related to photon's energy. You only need one photon to observe these.

Intensity is number of photons per unit area per unit time, so it takes many photons normally, but a single photon produces a non-zero intensity.