Have electromagnetic waves any polarity?

AI Thread Summary
Electromagnetic (EM) waves do not possess a charge but can interact with charged particles like electrons through their electric and magnetic fields. The polarization of EM waves is defined by the direction of the electric field within a two-dimensional plane perpendicular to the wave's propagation. While electrons can emit and interact with EM waves, protons can also emit photons, leading to interactions with electrons as described in Quantum Electrodynamics. The discussion highlights that these interactions can occur through various forces, including gravitational force, and emphasizes the role of virtual photons in these processes. Overall, the interaction between EM waves and charged particles is a complex interplay of electric and magnetic fields.
live4physics
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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 ? :confused:

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

Thanks :smile:
 
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Remember, charges interact with each other via the electric field.
 
very good... but the electric field (or magnetic) on EM waves has something like positive or negative signals?
 
live4physics said:
very good... but the electric field (or magnetic) on EM waves has something like positive or negative signals?

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.
 
why electromagnetic waves doesnot require any medium to propagate
 
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Only the electron particle can emit and interact with EM waves ?
 

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live4physics said:
Only the electron particle can emit and interact with EM waves ?
protons by them selves can emit photons , as well as other particles .
And some particle anti-particle collisions .
 
But can an EM wave emitted by the proton interact with electron ?
 
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 .
 
  • #10
live4physics said:
But can an EM wave emitted by the proton interact with electron ?

Yes.
 
  • #11
live4physics said:
But can an EM wave emitted by the proton interact with electron ?
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.
 
  • #12
does a photon interact with electric and magnetic fields .
 
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