Can electric field or magnetic field interact with an Electromagnetic radiation? And can 2 electromagnetic radiations interact with each other? Rather than the interference effect.
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1. Can electric or magnetic fields interact with an electromagnetic radiation?
- Electromagnetic radiation in terms of a classical interpretation is a combination of an electrical and magnetic field! Taking the classical Maxwell equations gives an explanation of how . The easiest way to see it is to look at the Poynting Vector.
$$ \mathbf{S} = \frac{1}{\mu_0} \mathbf{E} \times \mathbf{B} \\ u = \frac{1}{2}\! \left(\varepsilon_0 \mathbf{E}^2 + \frac{1}{\mu_0} \mathbf{B}^2\right)\!, \\ \frac{\partial u}{\partial t} = - \nabla \cdot \mathbf{S} -\mathbf{J} \cdot \mathbf{E}.$$
The Poynting vector $\mathbf S$ represents the directional energy flux of an em-field. If the energy density $u$ (B and E field) changes in time, you got radiation and Joulsche's dissipation. This is what the last equation express.
- In case you mean: Can an em-radiation, interpreted as an amount of photons, interact with em fields, the answer is also yes. But it is much more difficult to explain, and you have to use a quantization version of Maxwell equations --> quantum-electrodynamics (QED).
2. Can two radiation interact with each other?
Yes, QED, and especially quantum field theory (2nd quantization) shows a lot of such examples.
- For instance the superposition is violated for strong fields! That means:
$$\mathbf E \ne \mathbf E_1 + \mathbf E_2$$
- Photon-photon scattering
You can find a good and short description on this link.
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