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How can a photon have angular momentum if its path is always a geodesic?

If angular momentum is to be conserved (fundamental conservation 'law'), unless a photon can have angular momentum, how can your 'orbiting' electron lose any? Is it transferred to the Nucleus, perhaps?Does this work for the Hydrogen atom?

Quote from: DoctorBeaver on 26/05/2008 13:44:46How can a photon have angular momentum if its path is always a geodesic?The translational path of the photon is still a geodesic, but it's "rotating" as it moves along that path.

Quote from: DoctorBeaver on 26/05/2008 13:44:46How can a photon have angular momentum if its path is always a geodesic?The answer is either spin or polarization. Polarization angular momentum is fairly new, but it appears that light that is appropriately polarized is made up of photons that carry angular momentum: ...sorry, you cannot view external links. To see them, please REGISTER or LOGINThe translational path of the photon is still a geodesic, but it's "rotating" as it moves along that path.

Angular momentum is just a form of energy

Momentum, for an object with mass, is mv

I wrote:QuoteMomentum, for an object with mass, is mvA photon doesn't have mass but, when it bumps into something, it demonstrates it has momentum. In this case, the momentum is h/λ, where h is the Planck constant and λ is the wavelength.

So, are we saying that the direction of the angular momentum vector is somehow related to the direction of its travel? That would imply directivity in the production of a photon by a change of electron energy level.For a decay which produces a photon with no angular momentum, the changes in spin and orbital momentums must cancel out. Without doing the sums it seems to me that this must be only in a minority of cases as the possible spins are only +/-1/2 but there are many possible orbital changes.As for spiraling beams; how does that apply to 'one photon at a time' situations?