Have electromagnetic waves any polarity?

live4physics

Hi,

My doubt is how can the EM waves interact with an electron, i.e.,
electron is a particle with negative charge.. have EM waves any charge to attract or to repulse an electron ?

An example is the microwaves oven when waves interact with water molecules.

Thanks

Academic

Remember, charges interact with each other via the electric field.

live4physics

very good... but the electric field (or magnetic) on EM waves has something like positive or negative signals?

LostConjugate

The energy of the wave is measured in the 2D plane perpendicular to the direction of the field. There is 2 orthogonal dimensions and linear combinations of these. So the polarization of the wave is the direction (within this 2D plane) the field is moving in.

If you attach a string to an object and think of the string as the electric field, you can shake the string up and down or left and right or any linear combination of this. That is polarization.

physicsdoubts

why electromagnetic waves doesnot require any medium to propagate

live4physics

Only the electron particle can emit and interact with EM waves ?

cragar

protons by them selves can emit photons , as well as other particles .
And some particle anti-particle collisions .

live4physics

But can an EM wave emitted by the proton interact with electron ?

cragar

it could interact through the gravitational force , I wonder how the magnetic field of the electron would permeate through a photon's localized energy , if it would be different than permeating through a vacuum .

Academic

Yes.

K^2

That's basically the Quantum Electrodynamics description of Hydrogen atom right there. Proton emits photons that are absorbed by electron, and vice versa.

Virtual off-the-shell photons, mostly, by the way.

cragar

does a photon interact with electric and magnetic fields .