Do Photons Conserve Angular Momentum?

In summary, a photon is a particle of light that carries energy and acts as both a particle and a wave. Its angular momentum is related to its polarization and can be broken down into orbital and spin components. Photons can only have positive or zero angular momentum due to their spin, and angular momentum is always conserved in interactions with matter.
  • #1
Ontophobe
60
1
Do photons obey the conservation law of angular momentum?
 
Physics news on Phys.org
  • #2
There is no conservation law for single particles.
Processes with photons (and, in fact, all processes without external forces) conserve angular momentum.
 
  • #3
Thank you for the straight forward answer. What would constitute a process of photons?
 
  • #4
Every physical system where photons are involved.

Edit: Fixed weird typo
 
Last edited:
  • #5
refraction for example, wave interference also.
 
  • #6
Ontophobe said:
Do photons obey the conservation law of angular momentum?
Photons are circularly polarized ('helicity') to conserve angular momentum (Δl = ±1)
 

1. What is a photon?

A photon is a fundamental particle of light that carries energy and behaves both as a particle and a wave. It has no mass and travels at the speed of light.

2. How is angular momentum related to photons?

Angular momentum is a physical quantity that represents the rotational motion of an object. In the case of photons, their angular momentum is related to their polarization, or the direction of their electric and magnetic fields.

3. What is the difference between orbital and spin angular momentum of photons?

Orbital angular momentum of photons refers to the rotation of the photon's trajectory around an axis, while spin angular momentum refers to the intrinsic spin of the photon itself.

4. Can photons have a negative angular momentum?

No, photons can only have positive or zero angular momentum. This is because they have a spin of 1, which is always a positive value.

5. How is angular momentum conserved in the interaction of photons with matter?

Angular momentum is always conserved in any interaction, including those involving photons. This means that the total amount of angular momentum before and after the interaction remains the same. In the case of photons, their angular momentum can be transferred to the matter they interact with, or vice versa.

Similar threads

Replies
5
Views
1K
Replies
3
Views
1K
Replies
1
Views
322
Replies
2
Views
919
Replies
9
Views
3K
Replies
4
Views
1K
Replies
9
Views
1K
Replies
40
Views
2K
Replies
2
Views
873
Back
Top