Particle vs Wave Interpretations of QM

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selfsimilar said:
everything is made of energy
One issue with this statement is that energy is not an invariant. Different reference frames will give a different accounting of energy.
 
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Ordinarily yes we look at energy as a property and an accounting system more or less. But at the highest level in QFT eventually particles are created with creation operator pumping energy in a space time point. which although it does not indicate what it is it just says raised by so and so energy. So to me this time we are talking complete different language. Although, early on when relativity was in early stages even Einstein came up with the "relativistic mass" term which included the energy due to momentum pc. note we are talking about the energy that creates invariant mass that later was accepted. All I am saying is what QFT is saying, you can correct me if I am wrong.
 
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selfsimilar said:
at the highest level in QFT eventually particles are created with creation operator pumping energy in a space time point. which although it does not indicate what it is it just says raised by so and so energy.
A creation operator does not represent an actual physical process. (It's not even an observable since it has no eigenstates.) It's a mathematical device to construct states containing particles from the vacuum state.
 
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selfsimilar said:
But at the highest level in QFT
What do you mean by "highest level"? QFT and GR both form our fundamental understanding of physics.

selfsimilar said:
particles are created with creation operator pumping energy in a space time point.
Creation operators are a mathematical construct we use to do free field theory. We know how to manipulate the algebra of quantum harmonic oscillators so we took that mathematical machinery and use it in QFT.

I don't know what you mean by "pumping energy in a space time point".

selfsimilar said:
note we are talking about the energy that creates invariant mass that later was accepted.
We just call this the rest mass. It would be wrong / confusing to call it "energy".

selfsimilar said:
All I am saying is what QFT is saying, you can correct me if I am wrong.
No, what you wrote is not what QFT is saying.
 
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selfsimilar said:
pumping energy in a space time point

Again, energy is one of many of particles properties! As others have said, it does not work the way you think, but even if it did, those operators would "pump" also other quantities besides energy. I really don't like how pop-sci sources elevate energy to some superior quantity. The "holy trinity" of qunatities that arise from considerations about invariance of lagrangian under time translation, space translation rotaion is energy, momentum, and angular momentum. Latter two are equally important.
 
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A fundamental "particle" is an excitation in its quantum field. An excitation in a quantum field is energy. I don't think you can blame "pop sci" (although I think you can potentially blame "pop sci" for elevating the role of consciousness in quantum theory).

99% of baryon mass is the result of kinetic energy trapped inside the particle by the strong nuclear force, described by Quantum Chromodynamics (QCD).
 
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jeffn1 said:
An excitation in a quantum field is energy.
No, an excitation in a quantum field has energy.

jeffn1 said:
99% of baryon mass is the result of kinetic energy trapped inside the particle by the strong nuclear force
Sure, energy and mass are equivalent. That doesn't mean a quantum field excitation "is" energy, any more than it "is" mass. Energy/mass is a property of quantum fields.
 
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jeffn1 said:
An excitation in a quantum field is energy.

Sigh... Why on earth, after so many posts about what energy is, you decide to write this nonsense? Why did you ignore everything we said about that? Can you find any textbook that says what you said? Why not?

jeffn1 said:
I don't think you can blame "pop sci"

Then what can I blame? You won't findy what you wrote in any textbook on the subject. If not laymen literature, then you are just making stuff up. And that is against PF rules.


EDIT. Sorry for beating this dead horse, I didn't see @PeterDonis response.
 
weirdoguy said:
after so many posts about what energy is
is probably a Pandora's box better left closed. Physics is very good at defining how energy is calculated and what role it plays in a theory, but much less so at answering the ontological question of what energy is.
 
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Roberto Pavani said:
is probably a Pandora's box better left closed. Physics is very good at defining how energy is calculated and what role it plays in a theory, but much less so at answering the ontological question of what energy is.
Disabusing people of notions like everything is made of energy is well within the wheelhouse of physicists.
 
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Roberto Pavani said:
is probably a Pandora's box better left closed. Physics is very good at defining how energy is calculated and what role it plays in a theory, but much less so at answering the ontological question of what energy is.
I don't view it that way.

Energy as a concept is quite well defined and precise within each physical theory. Indeed that definition involves mathematics, but that does not suggest the theory only tells you how to calculate. For the theory does give labels to the mathematical objects and e.g. tells you that energy and velocity are not the same concepts.

As others have pointed out repeatedly, within our physical theories, energy is a property of "the stuff there is". What really is "the stuff there is" is a difficult ontological problem but that's not a problem with energy.
 
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