Talk:Democratic principle
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[edit] Ill-definition
The current version of this article fails to clarify the role of "distance" in computing the weights applied to each term (vote) before adding up the terms. This is of course a key weakness, since no-one seems able to explain what notion of distance is to be used here or why this notion would be physically preferred to all other possibilities. ---CH 23:47, 1 February 2006 (UTC)
[edit] Over-definition. DP is simple. Explain it simply. Don't invent new mathematical overhead to "explain" it, and then invent a whole research project around problems with the "new" explanation!
This is very odd: When I've come across Wheeler discussing the Democratic Principle, he's used it as a simple way of bypassing mathematical formalism, and demonstrating that you can work these things out without having to be a mathematician. I kinda thought that that was the whole point of it.
In his section on Gravity Probe B, he argues that all you need to do is to pick a location, use the relative gravitational field strengths of the Earth and the Background Universe at that location, and use that proportion to decide how much relative influence these two rotating bodies will have on defining "what constitutes a nonrotating frame" at the location.
The point of the democratic principle, I thought, was to show that you could use this simple argument to calculate effects like the GPB result as a "back of an envelope" calculation, to the accuracy of current experimental hardware, without needing any sophisticated mathematics. It was supposed (I thought) to be a quick-and-dirty principle that anyone could understand and follow.
So what happens? One Wiki editor decides that Wheeler was negligent in not providing an "advanced" specific mathematical formula for his principle, proceeds to supply one, then goes on to explain what the mathematical background might be for the equations that Wheeler didn't provide, and then sets out a plan for an entire math research project (!!) around filling in this additional (and apparently quite inappropriate) detail.
There may be a difference here between how a theoretical physicist sees a problem and how a mathematician sees it. If a physicist buys a pint of milk, its a pint of milk. Technically it might be 768 millilitres, but the filling machines may not be all that accurate, so really, practically, it's "a pint". To a mathematician, this may be equivalent to 769,000 microlitres, but to a physicist, to quote those extra figures is a professional sin -- it's inventing additional detail that can't be justified by context. One of the first things you are taught in physics classes is that you must NEVER overspecify data.
And that's what's happened in this article. It's over-specified. In physics, if a thing is vague, then one is supposed to reflect that vagueness in its description. If you are told that an event has happened, "Oh some time about mid-day, I guess", then when you write up your report, you don't log it as happening at 12:00:00.000 .
I think what's wrong with this article can be summed up by a comment in an earlier edit:
- " This engaging but ultimately exasperating book, which is difficult to classify as either an essay, a monograph, or a textbook, but contains elements one might expect to see in any of these, offers no mathematical statement of the democratic principle, but the version offered above seems close to what Wheeler might have in mind in Eq. (1.1.1). This book extensively discusses the gravitational vector potential and the gravitomagnetic vector field, unfortunately in a manner which encourages confusing GEM with a Mach principle.'
To me, this suggests that the editor has gotten frustrated that the material doesn't fit their usual classification schemes, has decided that there should be a strict formulation, and that it should fit, and has then set out to "correct" Wheeler's work by inventing their own statement of what they think he should have written instead. The editor then effectively defines a Wiki programme to explore how that editor's equations and formalism tie in (or don't tie in) with other branches of mathematical theory.
This is a perfect example of how specialists can sometimes take a simple idea and screw it up by not understanding appropriate context. If Wheeler didn't need, want or supply a precise math formulation, then Wiki shouldn't attempt to manufacture one on his behalf, especially if the result produces new problems that weren't there in the original work. If there's no accepted math formulation for the principle (perhaps for good reason), we shouldn't attempt to invent one ourselves as a "best guess". Since Wheeler is primarily a theoretical physicist rather than a mathematician, his principle seems to do its job admirably: it lets us predict physical results in situations like GPB to the limits of experimental accuracy as well as General Relativity does, without requiring all the additional overhead. To complain that it's "not sufficiently mathematical" seems to be rather missing the point.
I'm going to cut this article right down so that it corresponds to what Wheeler actually seems to have used, rather than some "better" principle that the editor might have preferred Wheeler to have come up with instead. I know that there's been a fair bit of work done on the article extending it, and I hate deleting other people's work on principle, but this piece seems to have turned into a monster that seems to be extrapolating wildly away from the original subject material, and where the editor seems to have stated that the specifics that they've introduced aren't in the literature and can't be cleanly obtained from it.
Involved technical discussions of Mach's Principle should be on those pages, and if the editor is hungry for a wider discussion of "Mach principles" , they have a page for that, too. But it shouldn't be here. Wheeler's "democratic principle" is simple ("everything votes"), and this page should reflect and honour that. ErkDemon 05:50, 26 April 2007 (UTC)
[edit] Lose the list?
 To-do list for Democratic principle: |
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Tasks for expert:
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I think this to-do_list should be removed, for the reasons above. It's contents don't seem to be justified, and I don't see any reference s to the discussion and consensus that are supposed to take place before one of these lists is created. ErkDemon 05:58, 26 April 2007 (UTC)
[edit] Finding reliable sources
I'm finding it hard to find any online reliable sources to back up this article.
A Google search for '"democratic principle" wheeler mach' finds some blog posts (eg: [1], [2]), but nothing more. The article itself contains an ArXiv link to a paper by Bahram Mashhoon, (the paper has since been updated to a new edition [3] -- I've fixed the link), but the word "democratic" does not appear to occur anywhere in the paper, and "Wheeler" occurs only once, in a citation used in the context of the statement 'gravitomagnetism ("GEM") has been discussed by a number of authors'. Can anyone find a reference to the "democratic principle" in this paper? Or indeed anywhere in the peer-reviewed physics literature, since an ArXiv search for the exact phrase "democratic principle" only finds two hits, both apparently referring to something else involving branes?
I can find a near-miss reference to "Galileo's democratic principle" in the Google Books preview of Magic universe: the Oxford guide to modern science, that mentions Wheeler in the next sentence, but it doesn't anywhere directly back up what the article says. -- The Anome (talk) 11:47, 15 May 2008 (UTC)
