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How does the electron make a photon in an antenna?

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raspberrypi:
We know how an electron makes a photon in an LED. It jump from a higher orbital to a lower one emitting a photon. But in an antenna its occupying the same valance just with a different nucleus each hop.  How is the energy transferred to a radio frequency photon?

switchedmodepsu:

--- Quote from: raspberrypi on February 07, 2017, 04:56:41 am ---We know how an electron makes a photon in an LED. It jump from a higher orbital to a lower one emitting a photon. But in an antenna its occupying the same valance just with a different nucleus each hop.  How is the energy transferred to a radio frequency photon?

--- End quote ---

I like that you think deeper than the average person. LIKE!  :-+  :-+  :-+

phliar:
In the electron case, it's about energy: if an electron needs to get rid of some energy it makes the appropriate photon.

The antenna case is easier to think about classically -- you're making changing electric and magnetic fields when you send a signal down a conductor, and these changing electric+magnetic fields have this cool self-propagation ability that we call electromagnetic radiation. The QM analysis is left as an exercise for the reader...  :)

calexanian:
I was taught, and I just did some google searching because its been so long, is that the actual radio wave propagation (In the common communication ranges) is purely electromagnetic and electrostatic based on Maxwells equations. They propagate independent of photons in a manner dictated by QED. The photons are just an emitted byproduct generated by the intrinsic energy of the signal itself. In other words an antenna is producing the EM field, but any photons that are being released are not the principal emission and nowhere near the frequency of the base band, or in other words the antenna does not emit electrons or photons as a primary mode, only fields. It emits no more photons than any other piece of metal with that amount of energy going on about it. Things get a bit more complicated as you go higher up in frequency though. Via QED more "Loss" of energy is expressed via photons until you have an infrared light source.  Somebody please correct me. Like I said. It has been a very long time.

Rick Law:

--- Quote from: raspberrypi on February 07, 2017, 04:56:41 am ---We know how an electron makes a photon in an LED. It jump from a higher orbital to a lower one emitting a photon. But in an antenna its occupying the same valance just with a different nucleus each hop.  How is the energy transferred to a radio frequency photon?

--- End quote ---

You are thinking too classical.

Photon is a wave.  "radio frequency photon" is just another packet of energy.  EM wave doesn't need to convert itself into a packet of energy called "radio frequency photon" in order to travel.  You can think of EM wave travels by endless induction.  Moving E field induces M field which induces E field which induces...

Don't dig too deep into how EM wave or photon travels.  You can't describe it unless you get into quantum mechanics.  Once you get into quantum mechanics, you are not longer dealing with electronics.   Electronics is largely a macro-science rather than micro-(quantum)-science of traveling photons.

In reality, or rather, in quantum reality, I really don't know what it means even for a particle to travel from point A to point B.  We all just have models that we think describes the world, but no one knows for sure.

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