ELI5: Why can’t magnets bend light, considering light is an electromagnetic wave?

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Photons don’t have an electric charge and thus are not affected by electro magnetic fields.


If you consider it as a particle, photon, it has no charge and so would not be bent. If you consider it as a wave, Linearity. Where the magnets field and the lights field would sum linearly, leaving each “undisturbed” by the other.


Light is a duality it acts like a wave and as a particle (depending on which is easier for you to work with) Light is essentially the byproduct of electrons – i.e. photons. Electrons and protons are impacted by the magnetic field of a manger because they are *charged* For example, engines and turbines and generators. Large amounts of electrons being impacted by magnets to generate large amounts of energy. Electromagnets are another great example. Photons on the other hand are *not charged* thus do not get impacted by the magnetic field of a magnet.


I remember placing a speaker with a large magnet on top of our CRT television when I was a kid and the screen colors at the top were all messed up… Taking the magnet off didn’t change the effect right away. It took a while for it to return to normal color. Is this not bending light with magnets?


When some particle moves due to an electromagnetic field, it’s due to the Lorentz force. The Lorentz force is calculated using F=q(E + v✕B). That is to say, the electromagnetic field, E, plus the cross product of the velocity of the particle with the magnetic field, v✕B, all multiplied by the charge of the particle q. So we don’t even need to worry about fields and vectors and cross products, because photons have no charge (q=0). Hence there is no force on the photon from any electromagnetic field, hence no bending of light.