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Definitely,i feel i have no way to understand this topics or related, what is auto-interacting or self-interacting particles, self energy,self-force, what is a self-interactive effect?

It's a broad question, but, i would like to know what questions one can make to learn more about it, how can i look for in google some literature, or is there some starting point.

I know there is a lot of threads that address this issue in a indirect way like Why isn't it obvious that a particle doesn't interact with its own field, classically? or others, but i like to know if exist some literature, in detail of this issue.

Community
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sigma2sigma
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  • In QFT we deal with self-interacting fields all the time. These occur anytime that the Lagrange an density has field products higher than quadratic. QCD is an obvious example. – Lewis Miller Jul 17 '16 at 03:04

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In physics a "particle" is the name of an approximation in classical mechanics in which we ignore all degrees of freedom but the center of mass motion of an extended body. Obviously, the "particle" in your question is a misnomer.

The problem you are talking about arises in classical electrodynamics with Coulomb's law. If we apply the formulas for the energy density of the electric field to a point charge (which is not the same thing as a particle!) and integrate over the entire space, then we get a divergent integral. This classical self-energy is therefor not well defined in classical electrodynamics. We have a number of options to deal with this. We can say that Coulomb's law is not valid below a certain radial scale (but then we need to find evidence for that, which fails) or we can acknowledge that classical electromagnetism can not deal with self-energies, at all. Strictly speaking, though, electrodynamics is incompatible with all forms of matter and one can not expect it to describe something that lies beyond its range of applicability. Just like matter in Newtonian mechanics is "a given" without self-consistent internal explanation, point charges in electrodynamics have to be accepted to exist and to behave in certain ways, without any further insight into their nature within the theory itself.

The solution to the riddle of stable matter comes in quantum mechanics, where matter becomes the low energy expression of quantum fields. However, even there the equivalent problem (vacuum self-energy) hasn't found a physically satisfactory explanation and we basically have to treat it, for now, as an unsolved issue.

CuriousOne
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  • Thanks. and the other question that involves fundamental forces, that there are some particles (or whatever) that, besides communicate the force, also they suffer it, like gluons. Now, is always desirable to kick off the self-interactions or whatever from a theory or alternatively, there is a way to deal directly, how to measure it or derive consequences from this "self-thing" ? – sigma2sigma Jul 17 '16 at 00:18
  • In a sense we do have self-interacting fields in the standard model. When multiple different fields (let's say A-field and B-field) interact with each other, the interaction between A and B will automatically induce effective A-A and B-B effects trough A-B-A , B-A-B etc. terms. That's part of what makes field theories so hard to work with. – CuriousOne Jul 17 '16 at 02:25
  • It's kind of mad[-dening], how can you answer a question you voted to close because it's unclear what you asking? –  Jul 19 '16 at 09:45
  • @user104372: The OP deserves to be told just how far off his current intuition is from proper physics. If I could have done this in a comment, I would have, but the comment format is simply too short. – CuriousOne Jul 19 '16 at 14:01
  • @CuriousOne, so it was pretty clear what he was asking, huh? :) –  Jul 19 '16 at 14:03
  • @user104372: If the question contains nonsensical language, it can never be clear what is being asked. It has four down votes, already, because it is not helpful for other users of the site. – CuriousOne Jul 19 '16 at 14:12
  • @CuriousOne, (a downvote came exactly with your last comment, what a coincidence, for an old thread!): it is your comment that is nonsensical and contradictory: if you think the question can never be clear and vote to close it, if you are consequent you refrain from answering it, actually you are saying it is impossible for a sensible reader to answer it. end of story. –  Jul 19 '16 at 14:18
  • @user104372: It doesn't seem to me that you have anything productive to contribute here. If you like to argue for arguments sake, so be it. Otherwise please take it up with the moderators. – CuriousOne Jul 19 '16 at 14:26
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    @user104372 I am with you. I have been following some of this person's writing. It is a shame he has so much reputation and probably so much funding from whomever unfortunate enough to be his source of funding. –  Jul 21 '16 at 12:19