Electric field and light and stuff

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SUMMARY

The discussion centers on the interaction between light beams, specifically laser beams, and electric fields, particularly in the context of parallel plate capacitors and nonuniform electric fields like those around a large metallic sphere. Participants assert that while Maxwell's equations suggest no effect in steady electric fields, quantum mechanics indicates that strong electric fields can lead to particle creation, specifically electron-positron pairs. Additionally, gravitational effects on light beams due to energy density in strong electric fields are acknowledged, alongside the Faraday effect's influence on light in magnetic fields.

PREREQUISITES
  • Understanding of Maxwell's equations and their implications in classical electromagnetism
  • Familiarity with quantum mechanics, particularly concepts of particle creation
  • Knowledge of gravitational effects on electromagnetic radiation
  • Awareness of the Faraday effect and its impact on light in magnetic fields
NEXT STEPS
  • Research the implications of quantum electrodynamics in strong electric fields
  • Explore the Faraday effect in detail, including its applications in optics
  • Investigate the relationship between energy density and gravitational effects on light
  • Study the behavior of light in nonlinear optical media
USEFUL FOR

Physicists, electrical engineers, and anyone interested in the interactions between light and electromagnetic fields, particularly in advanced optics and quantum mechanics.

crx
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Is there any effect on a light beam in a strong electric field? I'm thinking to a laser beam that passes trough a very long parallel plate capacitor. And what if we have an nonuniform, electric field, like in the case of a very large metallic sphere at a high electric potential? Thanks!
 
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Maxwell's equations are linear, so I don't think there would be an effect. The only way I could see there being an effect would be in the presence of a nonlinear medium instead of free space.
 
crx said:
Is there any effect on a light beam in a strong electric field? I'm thinking to a laser beam that passes trough a very long parallel plate capacitor. And what if we have an nonuniform, electric field, like in the case of a very large metallic sphere at a high electric potential? Thanks!

I would have thought that there would be no effect in a steady electric field but there might be a very very small effect during the build up of an electric field or an alternating electric field.
 
Quantum mechanics predicts that in a strong enough electric field, two light quanta of sufficient energy can turn into an electron and a positron. Actual real particles with mass, fermionic spin, charge and all.

Someone will no doubt point out that other conditions are needed, but the equations indicate that the probability of particle creation depends on the electric field strength.
 
That is a good point. I should emphasize that I was speaking in strictly classical terms.
 
If the field is Very strong, one could also add the effect of gravitational bending of the beam passing close to the region of higher field, but it would be due to the field's high energy density and not to the fact that it's an electric field.
 
Electromagnetic fields are not self interacting, per Dalespams post #2.

As lightarrow points out, there is a small gravitational interaction since the electromagnetic fields (the light beam and the electromagnetic field) both carry energy. (energy is a component of the Einstein stress/energy/momentum tensor.)

Another way to think of the answer:all radiation is affected by gravity...following the above logic.
 
sorry but have any of you heard of the Faraday effect?

light traveling through a medium IS effected by magnetic field and I presume, similarly an electric field.

http://en.wikipedia.org/wiki/Faraday_effect

right?
 

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