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The known forces, other than gravity, are mediated by specific particles that have characteristic masses and other properties.

https://en.m.wikipedia.org/wiki/Gauge_boson

(there might be a graviton, too)

With a Grand Unification Theory, they might turn out to be one force with several aspects (eg electroweak force), but that's not really a continuum.




Is "particle" the correct model, or is it just very useful?


What do you think a model is?

There are phenomena explained by the particle model, and there are phenomena that are not. This is true of all models, and it's a a strong claim that we could eventually land on a "correct" model at all.

To be fair, a "particle" as the term is used in quantum field theory doesn't refer to a billiard ball, it's a perturbation in a "field" and encapsulates behaviour which could be described as wave or particle or neither.


Oh come on, what do you think a leading question is?


"All models are wrong, but some are useful." [1]

[1] https://en.wikipedia.org/wiki/All_models_are_wrong


Or to paraphrase Beer:

The utility of a model is what it describes.


Noether's theorem [1] says particles vs. fields are the same thing. So "yes" to both.

[1] https://en.wikipedia.org/wiki/Noether%27s_theorem


Is the "correct model" even well-defined or remotely falsifiable?

In my view, we're sailing awfully close to metaphysical waters with phrases like that.


It is currently known that to probe the Planck scale is practically impossible, or implausible depending on your level of optimism.

That scale is the point at which we might gain some level of confidence that we know what "really" is a particle (or its constitution), whether it is truly a point particle or if it is just convenient to assume that at the present time.


Not just practically impossible, it is theoretically impossible. Given Heisenberg's uncertainty principle, observing a position with a certainty of the planck length would require it to have so much energy that it forms a black hole. Since you cannot get information out of a black hole, this makes observations below this scale impossible.

Of course, the scales involved are far beyond anything we have been able to probe. And this arguement relies fundamentally on the interaction between gravity and quantum mechanics, even though those theories are famously not compatable. So the 'theoretically' in theoretically impossible is doing a lot of work.


Are you asking if a photon is a particle or a wave? It is widely known to be something that our brains have trouble understanding, since it behaves as both at the same time. Thus, "shut up and calculate!" as the response when students try to figure out what quantum physics "means."


The latter.




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