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Comment by soveran | Hacker News Reader

All the paradoxes disappear if we use Quantum Field Theory instead of Quantum Mechanics. I would really like someone with deep knowledge on Quantum Theory to explain if something is wrong with a theory that otherwise makes a lot of sense to me. A good read on the topic is the paper "There are no particles, there are only fields" — https://arxiv.org/pdf/1204.4616.pdf

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Surprisingly, physicists are very much aware of the field nature of all "entities" in the world, having invented QFT themselves. Even more surprisingly, popular journalistic explanations simplify things considerably, making it seem that the thoughts of physicists are much less refined than they really are. To complete the trifecta of surprises, in the refined thought process of us physicists, using QFT, many problems and paradoxes of interpretational nature or otherwise remain with quantum theory that need to be resolved.

Regarding "in the refined thought process of us physicists...many problems and paradoxes...remain".

It seems to me that a true paradox in physics must mean a theory provides at least two different incompatible predictions for a given physical situation. Given the success of the Standard Model, that surprises me. Do you have an example?

The use of the word "paradox" in physics usually means any conclusion that is considered unacceptable or unnatural for any reason, even intuitive. In logic there are no paradoxes, only contradictions. As far as we know there aren't any contradictions in the standard model, but there are plenty of suspicious conclusions that we would like to see resolved either with greater understanding or a better theory.

Did you read the paper I linked to?

I did not read the whole thing, but I skimmed it. Its not a new-results type of paper. It is just collecting the works of other people and being careful about the language used. I have grappled with some of these issues/formalism/language in my own research as have many other physicists over the decades. The purpose of this paper is to argue that "Textbooks need to reflect that fields, not particles, form our most fundamental description of nature. This can be done easily, not by trying to teach the formalism of QFT in introductory courses, but rather by talking about fields, explaining that there are no particles but only particle - like phenomena caused by field quantization."

Notice that he is talking about teaching/talking/explaining. It is a for-teachers paper, not a for-researchers-working at-the-cutting-edge-of-fundamental-physics paper. And its nothing new. I taught an introductory level course on quantum mechanics recently and I refused to use the words "particle" or "wave" at any point in the course because I think they are confusing. I talked instead in terms of wavefunctions which is just an easier word for fields - at least as far as undergraduates are concerned.

This.

I did condensed matter Physics, where QFT isn't that essential, but from the QFT I did study the "it's all fields" way of looking at it came out quite naturally (well, how natural something as profoundly weird as QM can be, can be discussed..). So I fail to see how this can be considered particularly controversial.

I mean, if you want something controversial and non-mainstream, take the subject of this article, pilot wave theory.

PS: Do you have suggestions on a good introductory QM study materials (textbooks, online stuff,...) that emphasize the fields viewpoint?

You can say that the only thing that exists is the quantum wave function, as what basically this paper says (particles are epiphenomena). That is basically hard-line Everettianism e.g. many worlds. There are still problems. QFT does not explain gravity very well either.

The paper claims "it's neutral on the interpretations" - it is not.

You have the most senior research professor of physics at caltech admitting there are problems still - there are of course physicists that insist they have the correct answer or interpretation - the hard part is convincing enough physicists to agree with them, which they universally do not agree.

> You have the most senior research professor of physics at caltech

What is the ranking of seniority of research professors at Caltech? Are you implying that a research professor is somehow better than a “regular” professor?

>Are you implying that a research professor is somehow better than a “regular” professor?

Probably when it comes to understanding and forming opinions on cutting edge research. . .

The only reason why that particular research professor is not “just” a professor is that he was denied tenure at the University of Chicago.

irrelevant - what is the endgame of what you are trying to drive at in this thread?

I’m trying to understand if “most senior research professor of physics at caltech” is supposed to mean something different from “professor of physics at caltech”.

I don't think the paper assumes a many worlds interpretation.

that's what it claims, but that is the only way to make sense of "particles are epiphenomena" + "Thus the Schroedinger field is a space-filling physical field whose value at any spatial point is the probability amplitude for an interaction to occur at that point."

it is saying that the only thing that exists is the quantum wave function

the only theory with a hope of credibility/coherence that says the only thing that exists is the quantum wave function is many worlds.

Quantum Field Theory in plain English means "3D Array of Integers Theory".

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