Light in electrostatic potential

[lightarrow]

Is electromagnetic radiation affected, in any way, by a strong electrostatic field (or gradient of field)? Specifically, is it possible to reflect light with such a field or to confine an EM wave inside an electrostatic potential well?

 

[xepma]

From a classical point of view: no. Light does not interact with itself, therefore the resulting electromagnetic field would just be the sum of the electrostatic field and the radiated field.

From a quantum point of view scattering between photons is possible through the exchange of virtual electrons/positrons. However, it's contributions are of order $\alpha^4$ and higher, so these effects are severely suppressed.

But come to think of it, the electrostatic field doesn't store any momentum (you need a magnetic field as well for that), but the radiated field does. Conservation of momentum in the direction of propagation can't be violated, so reflection would be impossible.

 

[v2kkim]

If photons got scattered then do they change courses ? How about wave lengths ?

 

[akhmeteli]

Is electromagnetic radiation affected, in any way, by a strong electrostatic field (or gradient of field)? Specifically, is it possible to reflect light with such a field or to confine an EM wave inside an electrostatic potential well?

You may wish to google "delbruck scattering" - this is scattering of light in the Coulomb field of a nucleus.