Do Photons Conserve Angular Momentum?

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Discussion Overview

The discussion centers around whether photons obey the conservation law of angular momentum, exploring the implications of this conservation in various processes involving photons.

Discussion Character

  • Debate/contested, Conceptual clarification, Technical explanation

Main Points Raised

  • Some participants question if photons individually adhere to conservation laws, suggesting that conservation applies to processes rather than single particles.
  • Others propose that any physical system involving photons must adhere to the conservation of angular momentum.
  • Examples of processes involving photons, such as refraction and wave interference, are mentioned as contexts where angular momentum conservation is relevant.
  • A later reply asserts that photons are circularly polarized (helicity) to conserve angular momentum, indicating a specific mechanism by which this conservation occurs.

Areas of Agreement / Disagreement

Participants express differing views on whether conservation laws apply to individual photons or only to processes involving them, indicating that multiple competing views remain without consensus.

Contextual Notes

The discussion does not resolve the implications of conservation laws for single particles versus processes, nor does it clarify the definitions of the terms used.

Ontophobe
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Do photons obey the conservation law of angular momentum?
 
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There is no conservation law for single particles.
Processes with photons (and, in fact, all processes without external forces[/size]) 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
 
Last edited:
refraction for example, wave interference also.
 
Ontophobe said:
Do photons obey the conservation law of angular momentum?
Photons are circularly polarized ('helicity') to conserve angular momentum (Δl = ±1)
 

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