What is the Electromagnetic Wave in this Animation?

[marksyncm]

I've found this animation of an accelerated charge creating an electromagnetic wave:

http://www.tapir.caltech.edu/~teviet/Waves/field_a.gif

My question is regarding the perturbation I've encircled in green below:

Is this what we call a photon?

 

[ZapperZ]

Is this what we call a photon?

No.

Zz.

 

[marksyncm]

No.

Thank you.

Is it possible for you to point out the "photon" in the context of this illustration of the electromagnetic wave?

 

[ZapperZ]

Thank you.

Is it possible for you to point out the "photon" in the context of this illustration of the electromagnetic wave?

A photon is not an “object” that one can point to.

Zz.

 

[phinds]

@marksyncm, to expand a bit on what zz said, a photon exists only a the point of interaction between an electromagnetic wave and an atom. That is, an electromagnetic wave (a "beam" of light for example) does not contain any photons, it's just a wave.

 

[Nugatory]

Is this what we call a photon?

It is not, but you might perhaps be hoping for a more elaborate answer than that. Here's one:

You won't find a photon in any picture that shows electrical field lines, because field lines are a classical way of visualizing electric fields at a macroscopic scale; the diagram you posted shows how accelerating a charged object can generate classical electromagnetic radiation, no photons or other quantum mechanical effects involved.

As @ZapperZ says above, a photon is not an object that you can point at. You might want to try this thread and especially the first two posts for more information, or give Feynman's layman-friendly book "QED: The strange theory of light and matter" a try.

A quick and hand-waving answer is that when electromagnetic radiation (a classical phenomenon) interacts with matter, we observe that the radiation always delivers its energy and momentum in discrete amounts at a single point; when that happens we say "a photon was detected" at that point. However, the photon doesn't exist in any sense that even remotely corresponds to our intuition about the word "particle" unless and until that interaction with matter has happened.

 

[marksyncm]

Thank you all, this is now much clearer.