Talk:Zitterbewegung

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[edit] Deletions by Linas

Linas, please explain why you keep deleting stuff. So far you've proceeded to call some very well regarded physicists "cranks", and me a "vandal" for restoring information which is both relevant and sourced. I am willing to work with you here, but you're not giving me much to work with. Ok, so you don't like semi-classical theories, I got that, but that doesn't by itself make them invalid. ObsidianOrder 23:10, 29 December 2005 (UTC)

The article, as it was just a few minutes ago, looked good. Zitterbewegung is a rather old-fashioned term that should be defined because it is of historical interest, and does appear in textbooks. There's nothing wrong with stating its a semilcassical idea, and documenting how difficult it was to understand during the 1930's, and how much trouble it caused for physicists of that era, and how they got into serious arguments over it. But by the 1940's, physicists were finally able to "wrap thier minds" around the concept, and understood it to imply that anti-particles exist, and understood it to mean that the mass of the positron is equal to the mass of the electron. Indeed, the frequency is nu = E/h = mc^2/h with m just twice the electron mass. At this point, the term was set aside, and no longer actively "researched". Instead, it was pointed out to students first learning the Dirac equation, as a curious aspect of the theory of spin-1/2 particles. However, its nothing more than that; its a curiousty of the Dirac equation and its plane-wave solutions.
What I objected to was the linking of this old and curious term to some highly questionable "modern" research. Trying to turn it into something "more" is essentialy numerology that is unsupported by any exprimental knowledge or theoretical understanding.linas 01:33, 30 December 2005 (UTC)
I would say there has been quite a bit of interesting recent work that relies on this "historical curiosity": first, classical theories of electron structure with spin such as Barut & Zanghi (Phys. Rev. Lett., vol. 52, pp. 2009–2012, 1984, and also the Salesi & Recami cite you deleted); and second, stochastic electrodynamics, which is not really a single well developed theory (yet), but rather a number of attempts to formulate a stochastic classical theory that reproduces the results of quantum mechanics and quantum electrodynamics, but without some of the shortcomings. By the way if you doubt that zitterbewegung is closely related to SED, please read Haisch & Rueda (Phys. Lett. A, vol. 268, pp. 224–227, 2000).
"Highly questionable"? Says who? Regardless of what you or I think of these theories, we have to rely on sources, rather than on our opinions. I have cited (numerous) peer-reviewed papers, which supports my assertion that this is valid science. You have produced no evidence to the contrary, other than your own opinion. That's the problem in a nutshell. ObsidianOrder 03:02, 30 December 2005 (UTC)
I believe you are POV-pushing, and I really dislike the tone of this conversation. There are tens of thousands of papers published annually. There are libraries filled with tens of thousands of books. You can get a pretty good idea of what's mainstream and what's not by visiting a university library. What "evidence to the contrary" are you fishing for? The fact that Ed Witten has never written about this topic? What do you want, someone famous to drop by, and make a ruling or judgement on this? Would you accept that opinion? I believe that there is a vast amount of interesting physics and mathematics, and I believe that the saying "truth is stranger than fiction" is particularly apt for physics and math. It doesn't need to be embellished. linas 06:09, 30 December 2005 (UTC)
OK, there is one "objective" way of looking at this. Google up some of the other "zitterbewegnung in layman's terms" articles on the net, and you will not find a single ref to SED or Heisch or anything else along those lines. Instead, you will find detailed historical and mathematical accounts that this article is lacking. And if you don't want to google, then go to the library and look up Bjorken and Drell, and Itzykson and Zuber, or Landau and Lifshitz. These are standard references that treat this topic in a standard way. Anything outside the purview is non-standard. I read some of the cites you gave, and they are not just a little non-standard, they are a very non-standard. linas 06:18, 30 December 2005 (UTC)
Non-standard? Yes, you're absolutely right about that, but that's not what we were discussing. Your original claim was that it was pseudoscientific, which is something completely different from "non-standard". Are you not claiming that anymore? And does "non-standard" mean it shouldn't be included in an encyclopedia? You seem to be implying that "non-standard" or "non-mainstream", but scientifically valid, theories should not be included here. I think that would be very unfortunate. There are huge problems with SED and related theories as they stand now, but as you know there are different huge problems with the current "standard" theory as well, and that's exactly why it is important to include valid alternative theories. I think that as long as there is no mis-representation of the status of these theories, this is a very suitable subject for wikipedia. Science is a process, not a single truth from on high, and that what is standard now may not be so in a few years.
Regarding what evidence - well, if you could point to a physicist who has said on the record that it is pseudoscientific, I suppose, or evidence that papers on the topic have difficulty being publushed. It was your claim, you figure out how to support it. Incidentally, the three well-known books you mention may not discuss SED-like theories, but they were all written before 1980, and there was very limited work on SED at that time, as you can see from the bibliography. ObsidianOrder 16:50, 30 December 2005 (UTC)

[edit] Not responsible for spin

Although there were some suggestions in the past that zitterbewegung was responsible for spin this is no longer a mainstream view. An argument against this is found in the article itself. If zitterbewegung is the result of the interference between the large and small components of the Dirac wavefunction, a free particle at rest, which has no small component, should have no spin. But of course it does. The best explanation for the existence of spin seems to be that it is an intrinsic property of the Dirac equation. Xxanthippe (talk) 22:10, 19 February 2008 (UTC).