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There are no particles, there are only fields (2012)

36 points| primroot | 1 year ago |arxiv.org

35 comments

order

GlibMonkeyDeath|1 year ago

From the paper: "Phenomena such as 'particle' tracks in bubble chambers, and the small spot appearing on a viewing screen when a single quantum interacts with the screen, are often cited as evidence that quanta are particles, but these are insufficient evidence of particles."

Really? Wave packets that are indivisible energy blobs, and that make individual "clicks" on my detector sure seem to act like particles to me.

I get that the math implies these bundles are waves - that's the duality part. I don't think any physicist thinks that there is a "particle" embedded in the wave packet, though, like this guy is arguing - the quantized wave packet is the particle!

mensetmanusman|1 year ago

Are fields real though? If so, they point to a mathematical reality that is non physical.

strogonoff|1 year ago

There’s nothing “real” in physics. Everything is a model, and every model is necessarily flawed—otherwise would imply a provably correct, complete formal description of the actual-really-“real”. To obtain that even in theory we would have to observe the real from the outside, which we by definition cannot: we’re necessarily part of what we’re describing, so if we could look at it from the outside all we would get then is a new indescribable “real”.

Hence, a question like “are fields real?” is besides the point: it is impossible to tell whether that theory is wrong or qualify how wrong it is, because the reference point is never available. It’s a model—it works for some purposes, it doesn’t for others.

russdill|1 year ago

It really depends on what you mean by real. Many philosophers have adopted the stance that if a concept provides a useful way to talk about reality, it's real. There's no such thing as tables or chairs, but we consider them real because doing so is useful. By the same token particles are real because they are a really useful way to subdivide reality, even though their appearance is just a consequence of field theory.

andyferris|1 year ago

Why are fields non-physical?

ww520|1 year ago

Fields are real. They are physical as well as they are the basis of the physical world.

alphazard|1 year ago

The names are made up; the structures aren't, but they are only as good as they need to be and no better.

breck|1 year ago

Are there fields plural or is there one field singular?

My latest check of QFT is that there are 37 fields.

This leads me to believe:

- There is only 1 undiscovered fundamental field

- There are multiple gods and each complains about there being too many fields and how much simpler universe management would be if there was just 1 field and then https://xkcd.com/927

fsmv|1 year ago

Pretty sure you can just concatenate the field values together into one giant tensor and call it one field if you want.

tejohnso|1 year ago

> It's important to clarify this issue because textbooks still teach a particles- and measurement-oriented interpretation that contributes to bewilderment among students and pseudoscience among the public

Is this mostly settled then? And if so why do we continue to teach a bewildering model?

Starman_Jones|1 year ago

It's well settled, but not very useful. We still teach Newton's laws of motion, even though we know they're wrong, because it's a lot easier to work with than Lorentz transformations, and most of the time, the result is just as useful (eg, the Apollo missions used Newton's equations). When introducing chemistry, it's much easier to understand a water molecule as a combination of two hydrogen atoms and one oxygen atom than it is to understand it as fields representing the two elements interacting with fields representing fundamental forces. Heck, in order to even explain the forces, you would probably need to introduce particles.

munchler|1 year ago

Because it is way more intuitive to think about particles, at least at first. For example, particles have mass and momentum. Fields do not.