Are photons energy? What is energy, anyway?

So this whole "is a wave energy, or is it a form of energy", I think depends on the following:

Is a "wave" what the wave is made out of; water waves are "made out of water", right?
Is a "wave" what propagates in a medium, in which case it's not the medium but a state of the medium? I think that argument was settled way back in this thread.
(but, this is sciforums)

Water waves depend on water as they propagate, but the waves aren't the medium; in some sense they map a medium to itself, something like how a purely mathematical function can map a domain to itself.

And I really think the claim "energy is not stuff", should be amended to "energy is not measurable stuff, but it is physical".

 

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You know why. I already told you why in the ufo thread. Limit yourself to one or two paragraphs per post like everybody else does.

 

http://www.sciforums.com/threads/in-defence-of-space-aliens.160045/page-151#post-3601340

 

Read your sources more carefully. A photon is a quantisation of a field. It does not itself constitute the field. In the QFT picture, I mean.

Yes, a field has energy in it. No need to tell me to read Einstein's papers as this is what I have been saying throughout. However, saying it has energy in it does not mean it "is" energy. After all, a moving cricket ball has energy, too.

And yes, waves in a field can transmit energy: since they possess energy, move, and can be absorbed, this obviously follows.

 

Energy is just as "physical" as momentum, no more, no less.

That is to say, a quantity that cannot be directly measured but can be calculated from measurements, which is very useful in analysing the behaviour of physical systems.

Oh, and pass us that jug of momentum, would you, when you have a moment?

 

I'm just offering you some helpful advice. It's all on you if that somehow offends you.

 

This may be of interest;

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Light behaves as both particles and waves at the same time, and scientists have been able to observe this duality in action using an ultrafast electron microscope. The wave nature is demonstrated in the wavy upper portion, while the particle behavior is revealed below, in the outlines showing energy quantization.
(Image: © Fabrizio Carbone/EPFL)
https://www.space.com/wave-or-particle-ask-a-spaceman.html?utm_source=notification
Paul M. Sutter is an astrophysicist at The Ohio State University, host of Ask a Spaceman and Space Radio, and author of "Your Place in the Universe." Sutter contributed this article to Space.com's Expert Voices: Op-Ed & Insights.

 

Are solids compressed waves?

 

Just this, informs me that you don't have any real idea what I actually said about the Coulomb gauge. I said nothing about "pretending the proton isn't there", where do you get this stuff?
The Coulomb gauge you wrote down, is a way to represent the nuclear energy in the equation without redundant degrees of freedom. It isn't really an approximation, either, and that's another thing I want to ask: where do you get that from?

 

Because it's rubbish, mostly. Ok?

 

Oh, "physical" is a weasel word? I see.
But you seem to struggle with its meaning, repeatedly.

Physical need not be a thing which is "stuff you can put in a bottle". I can put a vacuum in a bottle, the bottle has "nothing" in it, is nothing a physical thing? It has a volume, maybe that's the physical thing. Or maybe nothing isn't really empty, or something equally vague.

 

Not until you show it fixes the charge of the proton at the origin, then its quite a reasonable assumption, James.

 

But there's a professor emeritus saying the particle is its field. An electron is its field, why isn't a photon its field?
This guy apparently does know a bit of QFT . . .