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Merging Rotational Motion

Both Rotational_motion and Rotation_around_a_fixed_axis are on near enough the same topic, and much of the content is shared word for word between both articles. I don't think there is really any dispute over whether they need merging, but what title should they be merged under? I think that 'Rotational motion' is the better option as it keeps things open. Also the article 'Rotation around a moving axis' does not exist, so 'Rotational motion' seems sufficient.

Once merged the article definitely needs some attention. The introduction in particular seems very comparative rather than directly informative. Iomesus 18:14, 12 June 2007 (UTC)

The simpler title is definitely preferable in my opinion. — Laura Scudder ☎ 23:25, 12 June 2007 (UTC)

The articles should clearly be merged. Both of them are about what I would call Rotation about a single axis, which would be my preferred title. This is the level at which first year physics textbooks talk about rotation. However, rigid objects can make more complicated rotations than just rotating around one axis at a time. This requires a much more sophisticated mathematical treatment than these articles attempt, which is useful for understanding tumbling projectiles and gyroscopes, among other things. In principle, Rotational motion could be about the general treatment of rotation, but I'm not offering to write it. Cardamon 07:51, 24 June 2007 (UTC)

New information on Lightning Page to Sprites

Appearently, the streeks or tendrils are incorrect. Using a fast past cameral, they found out that they are balls of lightning that shoot down then up at 0.1 the speed of light. Followed the talk page to here. So, not sure who takes care of lightning.

• Livescience article
• Video evidence
• older information, 1999

Thanks, CarpD 6/12/07.

• • I updated the Sprite information, please check my writing if you get a chance. Thanks, CarpD, 6/13/07.

Proposal for New Page

I would like to propose that someone who has enough knowledge on the subject creates a page called "Status of String Theory" which details the general consensus of the scientific community regarding the acceptance, falsification, and verifiability of String Theory.

I say this because as a layman, I do not have access to information on the latest tests with CERN or Fermilab colliders, and would like to know more about whether the theory ever is directly confirmed or not.

• This is an excellent suggestion, as most of us want to know about the state of the art in physics, appreciate that String Theory somehow meets this description, (if the hype is to be believed), but somehow are not easliy able to find accessible yet comprehensible summaries of this proposed physics. Maybe Ed Witten or someone of his calibre might jump in here. PD 19:43, 15 July 2007 (UTC)

Which special relativity?

It appears to me that there is not just one version of special relativity, but a range of versions which vary all the way from

• "Low" special relativity — Newtonian physics plus correction terms involving 1/c^2. For example, m is replaced in most places by m+E_k/c^2 to get the relativistic mass.

to

• "High" special relativity — general relativity with the Riemann curvature tensor fixed to be zero and thus the gravitational constant must also be set to zero.

Where in this wide range should we fix what we call "special relativity"? JRSpriggs 10:06, 22 June 2007 (UTC)

Should this kind of 'decision' not be based on what definition is used by most physicists? Or am I mis-interpreting your words "we" in your question, and you are asking what that definition actually is? Awolf002 20:51, 22 June 2007 (UTC)

To be more specific, we wikipedians sometimes use classical-like vector algebra with dot-products and cross-products (a 3+1 dimensional perspective), and sometimes use tensor algebra (a 4 dimensional perspective). In each case, we are describing the same physical content, but the way of thinking about it is different. Do we want to continue doing things in this haphazard way or do we want to settle on one method or the other? Or both, for that matter? JRSpriggs 07:17, 23 June 2007 (UTC)

Let's see, I do not have my physics text books handy, but I think what is mostly done is this: For the introduction of special relativity, tensor math is "overkill", since all you need conceptually is the 4 dimensional time+space vector and the Lorentz transformation. Then you insist on the necessary constraints (e.g. the invariance of physical variables in the equations) and you get to the mathematically correct formulation of special relativity. This seems didactically and historically sensible to me. Once, you need to expand this framework to address general relativity you would "complicate" the math by the more complex metric tensor g. How does that sound? Awolf002 08:08, 24 June 2007 (UTC)

Where, exactly, do you see "high special relativity" discussed? A quick skim of the WP article special relativity shows no such usage, which is in keeping with standard classroom presentation. The standard textbook presentation includes a hand-waving "just ignore gravity for now", and "you'd need to learn GR to understand gravity". Leave it at that. -- right? There are also concepts in cosmology about flat universes and what not, but these are inappropriate for an SR article. So I guess I'm saying that I don't understand what the issue is, or why there's an issue. linas 23:39, 28 June 2007 (UTC)

If you refer only to tensor math, then using both 3+1 and 4 is correct: the 3+1 approach is suitable for introductory discussion, while the 4D notation is for use after the concept is well-understood. Please note that even in GR, for calculations such as the precession of the perhilion of mercury, even then you eventually have to go back to 3+1 so that the astronmers can figure out where to aim the danged telescope. linas 23:39, 28 June 2007 (UTC)

I agree with Linas that the issue here confuses me. Is the issue that in elementary treatments one writes equations with time and space explicit and separate quantities, while in more advanced treatments one uses 4-vectors and the accompanying tensor notation? Joshua Davis 07:44, 29 June 2007 (UTC)

Tensor math does have a place in special relativity, even disregarding gravity altogether. The electromagnetic field is an antisymmetric tensor of order two, and the stress-energy tensor (also order two) does have uses in SR applications. Anarchic Fox 05:35, 4 July 2007 (UTC)

This occurred to me when I was thinking about the fact that I had written the section Lagrangian#Special relativistic test particle with electromagnetism in the 3+1D notation rather than the 4D notation, and I was wondering whether that was the right thing to do. Other than that, I did not really have any specific problem in mind. I just wanted to know whether you-all feel that we should have a policy about how we present special relativity. For example, the energy of a free particle could be written in several different ways:

${\displaystyle E_{k}={\frac {p^{2}+{\frac {E_{k}^{2}}{c^{2}}}}{2(m+{\frac {E_{k}}{c^{2}}})}}}$ where ${\displaystyle {\vec {p}}=(m+{\frac {E_{k}}{c^{2}}}){\vec {v}}}$ see Talk:Kinetic energy#Making the relativistic equation look more like the classical one

${\displaystyle E_{k}={\frac {mc^{2}}{\sqrt {1-{\frac {v^{2}}{c^{2}}}}}}-mc^{2}}$

${\displaystyle E=mc^{2}{\frac {dt}{d\tau }}={\frac {mc^{2}}{\sqrt {1-{\frac {v^{2}}{c^{2}}}}}}}$

${\displaystyle E=-mg_{0\beta }{\frac {dx^{\beta }}{d\tau }}}$.

Ultimately, these are equivalent, but they look quite different. JRSpriggs 10:31, 29 June 2007 (UTC)

The first eqn looks kind of weird and is pretty non-standard and confusing, suggest avoiding it entirely. The second and third are standard extbook presentation. The fourth is "landau-lifschitz"-y and is a part of a set of gymnastics routines for learning the 4D notation. In itself. its not very edifying; but as a part of a group of other related formulas having the metric tensor in them, it can help the reader get oriented. I remember dozens of expressions all having ${\displaystyle {\sqrt {-g_{00}}}}$ in the numerator or denominator. I call it "landau-lifschitz"-y because this material is suitable only for your brightest, most promising students ... linas 17:51, 29 June 2007 (UTC)

Fundamentals

In my opinion (and that doesn't say much), I think the most important thing to keep in mind on a topic like this is fundamentals. Think about it, if you set up your own equipment, it makes no sense not to continue and take it a step further! What do you lot think? — Preceding unsigned comment added by Deimtchek (talk • contribs)

Eh? What? What topic are you talking about? Which article? To what or whom are you responding? How about providing a little context! JRSpriggs 05:59, 24 June 2007 (UTC)

I think he was talking about SR--Cronholm 08:59, 24 June 2007 (UTC)

If so, I still do not know what he is asking. JRSpriggs 10:31, 29 June 2007 (UTC)

Magnetic field

Could we get some more eyes over at Magnetic field. I just stumbled onto it a few days ago, and it appears that an anon (81.***) seems rather insistent on passing of high school physics analogies as the real deal. I changed the intro, which had some oversimplification errors in it, using the intro in electric field as a model, which created IMO an accurate yet simple description. However, he/she reverted most of it this morning, I essentially reverted her/him, and I really don't want to be drawn into a revert war - hence my request to the project to bring in more outside eyes before going to a RFC. The anon seems obsessed with Faraday's lines of force, constantly saying the the Lorentz force law cannot explain all magnetic field interactions (like the attraction b/n two bar magnets) and even appears like he/she sees her/himself as a crusader against a conspiracy perpetuated by a physics "the Man" establishment (admittedly, some other knowledgeable editors may have been a bit gruff/short with the anon). Thanks in advance for any help. --FyzixFighter 15:55, 29 June 2007 (UTC)

A while ago I thought I'd take a stab at improving the page, but quickly realized it would take more effort than I was willing to put forth alone. One point: the introduction from a few months ago was mostly ok; you might want to dig back and look at it. --Starwed 10:26, 30 June 2007 (UTC)

Spin ice, Geometrical frustration and Geometrical frustrated magnets

I've just read the above articles. As far as I can see:

• Geometrical frustrated magnets should be called Geometrically frustrated magnets, and I propose to move it.
• Furthermore, much of the material there duplicates and expands upon what's at Spin ice.Theerfore, I propose to excise much of it and move it to Spin Ice

As far as I can see, a Spin Ice is not geometrically frustrated. It has a certain residual entropy, yes, but this is not as a result of any kind of frustration, but as a result of a large number of degrees of freedom. If this is correct (and I'm writing here in the hope that somebody will help!), then I think we should:

• Remove the example of ice from geometrical frustration
• Merge geometrical frustration and the newly created Geometrically frustrated magnets

Comments please! Chris 21:46, 29 June 2007 (UTC)

The new article, to which the old one was moved, is geometrically frustrated magnet; the title is singular, not plural. The plural would offend Misplaced Pages conventions unless some special reason for its use is cited. Michael Hardy 19:31, 6 July 2007 (UTC)

Abeles matrix formalism needs simplification and wikification

It would be greatly helpful if an expert could help simplify and explain Abeles matrix formalism. Anybody game?

-- Guroadrunner 07:58, 30 June 2007 (UTC)

No merge of thermal energy, internal energy, and heat

There seems to have been some kind of edit war brewing over the last weeks at the heat and thermal energy articles between several editors, primarily User:The Way, that caused User: ScienceApologist to quit Misplaced Pages. In any event, the situation still continues; please review Talk:Heat (disambiguation) and Talk:Heat and give your opinion or vote: here . --Sadi Carnot 04:08, 2 July 2007 (UTC)

Looks like this is resolved (no merges). Gnixon 16:41, 3 July 2007 (UTC)

Non-equilibrium thermodynamics: pseudophysics?

After a long period of stability, a number of edits were recently made to the John Bedini article in an apparent attempt to advance his unproven theories. This included replacing a longstanding statement that his device designs "do not adhere to the first or second laws of thermodynamics, which relate to conservation of energy" with what seems to be an agenda-advancing statement that the devices "(do) adhere to the laws of non-equilibrium thermodynamics".

I've reverted nearly all of the additions to restore the article to its relatively neutral and terse state. I did leave in a mention of non-equilibrium thermodynamics, though; it now says the devices "demonstrate principles of 'non-equilibrium thermodynamics' — that is, they do not adhere to the first or second laws of thermodynamics, which relate to conservation of energy."

However, I'm not sure the implied contradiction between the field of non-equilibrium thermodynamics and the laws of thermodynamics is correct; I'm just railing against what seems to be an attempt by proponents of his theories to dishonestly associate them with what is characterized in Misplaced Pages as a legitimate branch of physics.

So, is non-equilibrium thermodynamics legit, or is it pseudophysics? Should I characterize it differently? Is it even applicable? How can we continue to improve the John Bedini article? I'd appreciate some more eyes looking at it because I don't have time to police the article on my own. Thanks! —mjb 10:50, 5 July 2007 (UTC)

I looked over non-equilibrium thermodynamics and John Bedini articles. I've certainly know there is a field called "non-equilibrium thermodynamics"(although I think one would usually say "non-equilibrium statistical mechanics") but I'm not really qualified to judge an article about it. I would say that what I know about it loosely resembles what is in the article, but there could be major mistakes or misinterpretations. For instance, I know that entropy as it's usually thought of is an equilibrium concept and there is a bunch of research in progress about generalizing it to non-equilibrium settings. Also, the stuff about non-conservation of energy seems a bit dubious but could still be right. The energy of an open system has no reason to be constant(even in equilibrium thermo, if you have a system at fixed temperature one expects that the energy will have fluctuations about some mean value).

The John Bedini article seems fine as is. I think most(including myself) would say his ideas are pseudoscience but the article points out a lot of criticism leveled against him. The main issue there is whether or not he is notable enough for an article. If so, the existing article seems even-handed enough. Joshua Davis 20:33, 5 July 2007 (UTC)

After a very very quick skim of non-equilibrium thermodynamics, it looked perfectly legit. Was there something specific in there that seemed wrong? Joshua is right, this is a field generating active interest in physics. For example, recently, there was a new and quite legit experiment that demonstrated a momentary violation of the second law by building an actual Maxwell's daemon that somehow worked for a little while, using some trick I can't remember. Oh, why look, actually the article on Maxwell's daemon reviews this new work! Bravo. linas 02:24, 12 July 2007 (UTC)

The Maxwell's daemon article says the Leigh experiment (Nature 2007) doesn't violate the 2nd law because of its external power source. Gnixon 14:40, 12 July 2007 (UTC)

As to Bedini, this version is quite entertaining, a true melodramatic read, with dirt-floored basements and accusations of neglect. But Bedini is just a minor sub-plot to the real melodrama at Royal Rife. Wow! linas 02:44, 12 July 2007 (UTC)

(Light bulb goes off in Linas' head) I think I finally understand the appeal of pseudoscience: Its got all the thrills of reading fiction, be it whodunits or Harry Potter, with the added pleasure-twist that it might be true, and further, that you don't have to wait for the sequel, you can just dig more dirt yourself. Wow! linas 02:59, 12 July 2007 (UTC)

Exactly, and people who are into it always feel they're being censored and unfairly dismissed when they fail to achieve recognition for their untested but "clearly revolutionary (if it works)" theories. The author of the "1974 Crane, Rife, Bearden, Dr. Robert Strecker" section you're referring to and which I deleted is trying (and failing) to make a case for it to be restored on the grounds that Bedini and Rife's work needs more publicity, and on the grounds that if Albert Einstein's article and its forks can have controversial details explained at length, so should these guys' articles. I didn't point out the obvious bit that Einstein has been and continues to be written about at length, but I did mention that these arguments are typical of people who want to misuse Misplaced Pages and that WP policies were devised largely to prevent this sort of thing.

I acknowledged that he might have a case for retaining a mention (with careful wording) that in 1974 Bedini and others sought to validate certain claims of Rife and that the group drew certain conclusions and that a video exists which purports to demonstrate some of Rife's claims. However, all the drama and details of the experiments in the rambling prose that I deleted is inappropriate for a Misplaced Pages article. Why do pseudoscientists and their followers always ramble incoherently?

Anyway, I'm afraid the Rife and Bedini enthusiasts are going to continue to flout the spirit of the policies and guidelines while attempting to adhere to the letter, which could lead to more questionable references to perhaps legit but immature and possibly irrelevant fields like non-equilibrium thermodynamics and citations of books related to it. —mjb 08:39, 12 July 2007 (UTC)

Specifically, it is the personal drama that makes pseudoscience interesting. Real science tends to stick to cold, impersonal facts. The history of science can record the drama, but by the time the history is written, the science tends to be done, and the drama is over. By contrast, the history of pseudoscientists is rarely written and documented, and so one is very much in terra ingocnita, one is actively unravelling a mystery. Better yet, the mystery does not require a PhD and a research budget to unravel; almost anyone can participate. The drama is far from over; it remains a living thing that can continue to be mined. The very act of suppression is what makes it a gnostic pursuit. linas 04:26, 13 July 2007 (UTC)

Strange syntax

As a mathematician I'm accustomed to such usages as this:

It follows that

${\displaystyle a^{2}+b^{2}=c^{2},\,}$

where a and b are ....

etc. Lately I've come across a number of Misplaced Pages articles that say things like this:

It follows that

${\displaystyle a^{2}+b^{2}=c^{2}.\,}$

Where a and b are ....

A period is put at the end of the equation and the initial W in Where is capitalized as if it's the beginning of a new sentence. Or sometimes the period is omitted; it seems physicists (at least here on Misplaced Pages) often omit the period after an equation even when it's at the end of a sentence. The first time I saw this I thought it's obviously a gross gramatical goof by someone who wasn't paying attention to what he was writing. After a couple of dozen times, I'm thinking maybe this usage is actually standard among physicists. Can anyone confirm or deny anything? (Sometimes in certain moods I start to wonder if physicists consider it their sacred duty to be offended by any attempt to be precise in the use of language.) Michael Hardy 12:33, 5 July 2007 (UTC)

The second version looks like it uses incorrect grammar to me. Feel free to fix it. (I wish that the journals in my subject has some style guidelines regarding the integration of equations into sentences.) Dr. Submillimeter 12:47, 5 July 2007 (UTC)

Most physics journals officially use the Chicago Manual of Style, a document which most physicists (including me) have never read. Physicists are not offended by precise use of language but most don't consider it to be part of their job description. We tend leave journal copy-editors to fix errors like the one you mention (on WP, guess that means you!). On lax usage in general, it's telling that interational standards and conventions on fundamental physical quantities are usually agreed by engineering organisations (e.g. IEEE), not organisations of physicists. PaddyLeahy 16:52, 5 July 2007 (UTC)

The first version is correct. The second is a result of sloppiness or (forgivable) ignorance. Gnixon 18:51, 5 July 2007 (UTC)

I would agree that the first version is correct(the second seems very bad from a grammatical point of view). Out of laziness punctuation is often omitted after equations, but I wouldn't call it a "physicist style". It's true that we physicists get a little ornery when criticized on the precision of our language; kind of a quirk of the field, I guess. Joshua Davis 20:16, 5 July 2007 (UTC)

Tesla Coil

It's been suggested to me that I mention the status of Tesla Coil. I don't know how to put this delicately, but someone making extensive "contributions" is a free energy enthusiast and does not seem to know much about electricity. I haven't gotten through my electromagnetism book yet (blush), but I've designed and built a MOSFET Tesla coil, and done EE professionally for many years. Somebody put a banner on the page saying that it was within the realm of Misplaced Pages Project Physics, but they don't seem to have stuck around. Anybody who knows the subject is welcome to weigh in; very welcome; that's all I'm saying. FETSmoke 04:12, 6 July 2007 (UTC)

Relativity priority dispute

I'm wondering about the legitimacy of the sources in this article. In particular, some of the self-published stuff by Bjerknes raises some eyebrows, particularly since it's hosted on a website called jewishracism.com.-Wafulz 01:24, 10 July 2007 (UTC)

As it is generally taught in college courses, there was some dispute about the chronology of Einstein's discoveries and whether others had discovered some of the key ideas before him. This is especially true with regards to the differential geometry of G.R. which was a particularly amazing acheivement for Einstein seeing as he was not trained as a mathematician unlike Riemann and others working on the problem. Nevertheless, the consensus of historians of science has been that Einstein is rightly credited with the discovery, though the great man theory of history probably has something to do with why he is remembered more than his predecessors. Einstein disparaging is a popular anti-Semetic passtime and so we need to be careful that we do not give a springboard for that kind of advocacy. --Mainstream astronomy 13:47, 10 July 2007 (UTC)

The article's coverage of Bjerknes is interesting. He published a book "Einstein: the Incorrigible Plaigarist." An author of an earlier Science article on the subject reviewed the book very critically in Physics World, calling Bjerknes "monomaniacal." Bjerknes' reply to Physics World was declined publication. As Wafulz seems to be pointing out, that section of the article appears to take pains to describe Bjerknes favorably. Some sections of the article probably have WP:NPOV#Undue weight issues. Gnixon 03:10, 11 July 2007 (UTC)

The explanation I've heard is that Poincaré and Lorentz knew the transformation before Einstein published his paper on SR, but Einstein was the first to derive them from basic postulates (that the speed of light is universal and that the laws of physics are the same in all inertial frames). Anarchic Fox 09:34, 14 July 2007 (UTC)

Egads, why is the article so long? Huge chunks of it are block quotes, too. — Laura Scudder ☎ 14:48, 11 July 2007 (UTC)

X and Y bosons

There is a merge proposal, standing intact for months, to merge X boson and Y boson articles into X and Y bosons, just like W and Z bosons have common article. So it would be really good itea to merge those two, because X and Y bosons are related in same way as W and Z bosons.

It also looks like there is extremely low edit activity on those articles. --83.131.77.66 15:56, 10 July 2007 (UTC)

Incredibly mindless merge done. — Laura Scudder ☎ 20:28, 14 July 2007 (UTC)

Galileo

Galileo Galilei has been nominated for a featured article review. Articles are typically reviewed for two weeks. Please leave your comments and help us to return the article to featured quality. If concerns are not addressed during the review period, articles are moved onto the Featured Article Removal Candidates list for a further period, where editors may declare "Keep" or "Remove" the article from featured status. The instructions for the review process are here. Reviewers' concerns are here.

Fritz Zwicky and Tired Light

I have recently been cleaning up the biography of Fritz Zwicky. It had originally included an enormous amount of material relating to tired light, IMO far out of proportion to its importance in a biography. But much worse, all the material related to modern fringe ideas by Lyndon Ashmore in particular. Similar problems have existed, and been resolved, in the past in the Tired light page. My changes have just recently been reverted or partially reverted by an anonymous editor, and the modern tired light stuff is back, justified by appeal to the authority of Feynman and Ashmore. I am new to Misplaced Pages and don't know the best way to handle this. I requested 3rd party assistance; a 3rd party Misplaced Pages expert duly showed up and declared the dispute a bit too technical. I have flagged the contentious section as being under dispute and indicated a drastic edit I wish to apply in the discussion page; which is essentially another revert to what I did a few days ago. Input from people with good understanding of the relevant physics and of Misplaced Pages conventions would be very much appreciated! -- (Duae Quartunciae 10:51, 13 July 2007 (UTC))

I reverted back to your version which is more in keeping with WP:UNDUE policy. Good luck. --Mainstream astronomy 13:39, 13 July 2007 (UTC)

I reverted the changes by Mainstream astronomy, which were a little hasty. I think enough consensus is developing at Talk:Fritz Zwicky for trimming the section. We just need to give this a little more time, perhaps just a couple more days, to allow for other people to comment. (Besides, Duae Quartunciae could improve his passage.) Dr. Submillimeter 14:03, 13 July 2007 (UTC)

Thanks all. The problem seems to be fixed. One guy had some difficulties comprehending WP:NOR, and has now taken his ball and gone home. I've put up an improved version of what was there before (thnx Dr. Submillimeter) and am now cleaning up the rest and adding a bit more stuff to make it a real biography. We can call this a wrap; though if anyone has useful input on the article feel free to jump in. -- Duae Quartunciae 07:03, 15 July 2007 (UTC)

Cosmosophy prodded

User:Banno on July 12 2007 WP:PRODed cosmosophy. 132.205.44.5 18:51, 13 July 2007 (UTC)

Velikovsky

I lost my account password on my other computer and so began editing as User:Velikovsky to look at some of the catastrophism pseudoscience. I was surprised that Ian Tresman was editing he is extremely well-connected in the Society for Interdisciplinary Studies and makes much of his living by doing web-design for that group. I don't think he should be editing those pages and posted a WP:COI warning on his page which he did not take kindly too. He also reverted a change I made to Anthony Peratt's page about his new-found amicas with Velikovsky supporters. This user reverted it and placed a warning at User talk:Velikovsky. I'm in over my head. Can anyone help me? --Mainstream astronomy 20:04, 14 July 2007 (UTC)

I would recommend posting comments about this at WP:ANI and asking for administrator intervention. Dr. Submillimeter 20:19, 14 July 2007 (UTC)

• Project-Class physics pages
• NA-importance physics pages
• Project-Class physics articles of NA-importance