Do photons obey the conservation law of angular momentum?
There is no conservation law for single particles.
Processes with photons (and, in fact, all processes without external forces) conserve angular momentum.
Thank you for the straight forward answer. What would constitute a process of photons?
Every physical system where photons are involved.
Edit: Fixed weird typo
refraction for example, wave interference also.
Photons are circularly polarized ('helicity') to conserve angular momentum (Δl = ±1)
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