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A short, simple enough question, if you know about field theory, which unfortunately I don't.

Are vacuum fluctuations more probable near a charge, for example an electron with negative charge?

I think this is one of the problems the renormalization procedure resolves, but if they are more probable, is there a clear mechanism for this?

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  • $\begingroup$ Vacuum fluctuations are not physical phenomena. In a sense they are a very unfortunate choice of words because they imply the existence of thermodynamic fluctuations in a quantum mechanical object. That's just not the case if you reflect on the actual meaning of the dynamics in quantum mechanics. $\endgroup$ – CuriousOne Jun 9 '15 at 19:08
  • $\begingroup$ What precisely do you mean by vacuum fluctuation? To see that this is really a crucial question, compare the notion in the following questions: physics.stackexchange.com/q/146003/50583, physics.stackexchange.com/q/16851/50583, physics.stackexchange.com/q/168398/50583 and others, where various notions are declared non-existent, trivial or interesting but misunderstood. $\endgroup$ – ACuriousMind Jun 9 '15 at 20:22
  • $\begingroup$ @ACuriousMind yes , from other posts I have read, I fully admit that I could easily be getting this concept confused and that it is crucial to get the wording and physical ideas underlying it correct. I will look through the links you provided, thanks very much. $\endgroup$ – user81619 Jun 9 '15 at 20:33
  • $\begingroup$ @CuriousOne as I have commented above, mea culpa for paying too much attention to popsci versions of this concept. In my defence, I think it is a widely misunderstood notion, maybe not. If I can't figure it out from the posts listed above, I might try a question to try and nail down the concept correctly. Thanks v. much $\endgroup$ – user81619 Jun 9 '15 at 20:41
  • $\begingroup$ It's perfectly fine to bring these questions. We are trying to correct misinterpretations of physical terms wherever we can. Physics is, after all, more than just math. $\endgroup$ – CuriousOne Jun 9 '15 at 20:53
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Are vacuum fluctuations more probable near a charge, for example an electron with negative charge?

I'm going to say no, because renormalization is more to do the virtual particles of QED rather than vacuum fluctuations. As for virtual particles, see Matt Strassler's article and note this:

"The best way to approach this concept, I believe, is to forget you ever saw the word 'particle' in the term. A virtual particle is not a particle at all".

They aren't short-lived real particles that pop into existence like spontaneous worms from mud. Instead they're "field quanta". It's like you divvy up an electron's field into chunks and say each is a virtual particle. The field is more intense closer to the electron, or a proton. Then when the electron and the proton attract one another they "exchange field" such that the hydrogen atom doesn't have much in the way of a field left. But there aren't any actual photons flying back and forth. Hydrogen atoms don't twinkle. And vacuum fluctuations aren't the same thing as virtual particles. For an analogy, if a real photon is an oceanic swell wave barrelling along at 8 knots, the virtual photons are a sloped abstract chunks of it, and vacuum fluctuations are something like the little ripplets on the surface of the sea. They're responsible for the Casimir effect. But the force there is very weak, unlike the immensely strong Coulomb force between the electron and proton.

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  • $\begingroup$ Thanks very much for your time John, I need to read a good bit more to get the full picture. I did look up the Casmir effect earlier but it did not click with as it should have done. As you told me before, ask more questions if needed and I probably will on this subject. I will read your answer very carefully, I see my wrong assumptions jumping out at me already. $\endgroup$ – user81619 Jun 9 '15 at 20:49
  • $\begingroup$ Classical comparisons are really not helpful. You can look at the fluctuation-dissipation theorem and then it's obvious that all these "ripplets" would automatically act as a dissipating force. Quantum field theory simply doesn't work like that and there is no such dissipating force, not even on photons across the entire visible universe. $\endgroup$ – CuriousOne Jun 9 '15 at 22:04
  • $\begingroup$ @Acid Jazz : my pleasure. But do note that it can be very difficult to give an answer that's both simple and accurate. And that problems then arise because popscience is often incorrect, and even qualified physicists believe in it. For example, Wikipedia says a virtual particle is "an explanatory conceptual entity". That's good. But compare and contrast with this or this. Some seemingly authoritative descriptions are popscience garbage, and it really doesn't help. $\endgroup$ – John Duffield Jun 10 '15 at 7:12

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