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There is a problem which appears to afflict most of the articles on Special Relativity. They are not consistent with the International System of Units. Ultimately this is because you-all are using ct (i.e. meters) as the time coordinate rather than t (i.e. seconds). But it results in you having the wrong versions of the Minkowski metric, the momentum 4-vector, the velocity 4-vector, etc.. I cannot fix all of them myself because there are too many such articles and I am sure that I would encounter significant opposition from people who suffer from the mistaken prejudice that every component of a tensor must be in the same units. For a correct understanding of how to assign units to the components of a tensor see E.J.Post, Formal Structure of Electomagnetics: General Covariance and Electromagnetics, Dover Publications Inc. Mineola NY, 1962 reprinted 1997.
Even worse, some people do not seem to realize that one must distinguish between the covariant and contravariant versions of a tensor. JRSpriggs 07:49, 11 September 2006 (UTC)
Units are an unnecessary complication in physics. It's simpler to just put c = h-bar = G = 1 and stop arguing about this. If you want to express time in units of seconds then just convert it to seconds. There is no need to put the factor c in formulae just because people might use incompatible units for space and time. Count Iblis 16:40, 11 September 2006 (UTC)
For example, Four-momentum says
but I contend that it should say
and also
If (as SI units demand) we use t in seconds for time and give the spatial coordinates in meters, then the units of a component of a tensor should be (meter/second)^n times the units of the purely spatial components of the tensor where n is the number of covariant time indices minus the number of contravariant time indices of the component in question.
Is this merely a matter of convention? Yes, but so is the use of SI units. People need to use consistent conventions to avoid being confused and to get the right answers when doing calculations.
Why not use natural units? First, because they are not the standard which is generally used in society (i.e. SI units). Secondly, if c is left out of the equations, then people will have to figure out where to put it in when they convert units. If it is already there, they can just substitute in the appropriate value for the system of units they want to use, whether that value is "299,792,458" or "1" or "186,282.397" or whatever.
Is it merely a silly historical artifact that we use both meters and seconds? Not really. Human activities are conducted almost exclusively at speeds much lower than c. The units we use in everyday life should be such that they yield numerical values which are near one rather than many orders of magnitude off. That requires a different unit for time than for distance.
What you-all are doing currently is building a conversion of units into the process by which you apply your equations. But that makes no sense. Tensors are already designed to handle all such issues. Just let them do it. JRSpriggs 07:52, 12 September 2006 (UTC)
Count Iblis 16:53, 15 September 2006 (UTC)
Hi everyone,
Photon seems to be getting close to becoming a Featured Article. But we would really appreciate your suggestions on how to improve it before we submit it as an FA candidate. Please take a few minutes to review the article and give us your advice on whether it's ready to be an FA at Talk:Photon. Thanks muchly! :D Willow 19:21, 11 September 2006 (UTC)
Sort of. EmDrive. The keepers are already piling up at Wikipedia:Articles for deletion/EmDrive, so we have another of those pesky pages to look after. -- Pjacobi 16:43, 13 September 2006 (UTC)
Newton first published his remarkably concise and simple formalism about Nature in 1687. His three Laws of Motion turned out to be far ahead of their time, more accurate than the accuracy of experimental data available to Newton. More than three centuries later, after Classical Mechanics was taken to its climax, considered a dead science and resurrected once more, they remain the prototype of physical theories and high practical utility. More sophisticated reformulations of classical mechanics, while in many ways outstripping Newton's original formulation which seems almost childishly simple compared to the level of mathematical complexity inherent in these formalisms, still lose to Newton's Laws of Motion in terms of practical usefulness because of their failure to model systems with the dissipation approximation.
It is sad indeed, therefore, to see our article on this remarkable theory of Physics lie neglected. The level of exposition is suited to Children's Learning Library, not a serious encyclopedia. Nothing is mentioned about the significance of inertial reference frames. No reference is made to the interpretation of the first law of motion as a definition, no explanation is given why the first law must be considered independent of and preceding the second law. Detailed discussions are not provided about the validity of the third law in the context of classical electrodynamics. No mention at all of their reformulation without using the concept of force, depending on momentum and energy. Very important topics such as the role of Galilean relativity in Newtonian mechanics and the subsequent need to formulate the theory in terms of fiber bundles is absent.
My grasp of physics is not advanced enough to undertake these tasks without the fear of mistake, therefore I appeal to you to improve this article. The current state of the article, particularly in comparison with our articles on Lagrangian Mechanics, Hamiltonian Mechanics, Hamilton-Jacobi equation etc, gives the distinct impression that the contributors considered NLM to be a theory without any mathematical beauty or elegance behind it, something only children do. This situation must be rectified, most importantly for students just learning the theory who may visit our pages for an extended perspective and academics who may have lost sight of the theories remarkable power when faced with the cacophony of alternative theories. Loom91 11:53, 14 September 2006 (UTC)
Hi everyone,
Photon is now in peer review, in preparation for its Featured Article candidacy. Please take a few minutes to review the article and give us your advice on how to prepare it to be Featured — thanks! :D Willow 11:31, 15 September 2006 (UTC)
As per #Automatic adding of project banner to articles in Category:Physics above, I've put together an initial list of physics categories for auto-tagging with the project banner. The list is currently located at User:Mike Peel/Physics categories. I'd appreciate people's help at trimming down the list to only those appropriate to physics (my selection method wasn't that accurate), as well as adding any that I've missed. I'd also like to pose a question: does this Wikiproject also cover astronomy, or should a new wikiproject be established to cover that? Thanks. Mike Peel 18:38, 16 September 2006 (UTC)
Someone's theory of everything, "licensed" under the GPL!; this one says we all live inside a hydrogen molecule. The AfD is here...it started quite well, but now the usual accusations of being the people who burnt Giordano Bruno are coming up. Oh dear. Byrgenwulf 11:13, 18 September 2006 (UTC)
I've recently noticed User:Kingbotk's application of the Template:WPBiography template to articles within the living persons category. Would it be worth me approaching him to ask if he could do something similar with the articles in Category:Physics? Additionally, it seems that he can classify articles within the appropriate stubs section as class=stub, which also may be worth doing. The process would not be able to classify the articles by quality or class, excluding the stubs, so although they would appear in Wikipedia:Version 1.0 Editorial Team/Physics articles by quality, they would be marked as unclassified. Mike Peel 13:53, 21 August 2006 (UTC)
Another approach to getting this done would be to make a request at Wikipedia:Bot requests. What do people think - is this worth doing? Mike Peel 22:06, 29 August 2006 (UTC)
<-- Me again! My plugin has come on in leaps and bounds (see User:Kingbotk/Plugin) and I think the version I'm testing now ready for release later this evening will interest you.
The plugin can tag talk pages with WikiProject banners. If the template doesn't exist on the page, it creates one; if it exists under a different (redirected) name, it renames it to the "official" name. Existing parameters which are already on the page are retained, and new ones added which have been selected by the operator. If the article is a redlink (it sometimes happens that articles get deleted after the list has been built but before the bot gets there) it skips it. If the talk page template is misconfigured it skips and logs it. The beauty of all this is that it happens transparently - drop the plugin file into the AWB folder, click a few checkboxes, and off you go. A recent version also added support for reviewing and assessing articles manually, but I'm not aware that anybody's used that feature in anger yet.
Until now I've only supported specific, very complex templates ({{ WPBiography}}, {{ WPMILHIST}} and {{ WP Australia}}). The changes I've just been working on allow the plugin to work with the template of any WikiProject, provided it has a class= parameter (which yours does). Ideally, the template should have needs-infobox=, attention= and auto= parameters too (you can steal some code for these from {{ WPBiography}}). I call these templates " Generic WikiProject templates".
Anyway! To get to the end of a long story, I've just had my bot tag Category:Australian physicists with 3 templates, WPBIO, WPAUS, and "Physics generic template". Example diff: [1] Example where some templates already existed and only Physics got added: [2]
Hope that helps. Any more questions you can ask me here as I'll keep this page watchlisted for a while longer. -- kingboyk 18:08, 18 September 2006 (UTC)
John Baez has posted a public letter from Greg Egan about New Scientist magazine at The n-Category Café. Since the issue of this magazine's reliability (and how much "notability" its august aegis actually confers) has come up here a few times, I figured I should post a link. Quoting the first few paragraphs from Egan:
I like the word gobsmacked. Anville 17:46, 19 September 2006 (UTC)
Hey physics guruz, a couple questions have come up in recent editing, and I thought I'd get some expert advice. They both relate in some way to the possibility of physically real infinities. One is whether there is a consensus that the universe (the whole universe, not just the observable universe) has finite mass. The other is about just what "observable universe" means. I'll break them down into subsections for ease of discussion. -- Trovatore 07:46, 21 September 2006 (UTC)
This discussion came up at infinite monkey theorem. An editor there had made a calculation (a bit OR-ish, but that's not important right now) about how long it would take to get a certain part of Hamlet's famous soliloquy if every atom in the universe were a monkey, or something along those lines. He claimed that this means the whole universe, not just the observable universe.
I doubt that any such thing is known. As I understand it, if the universe is asymptotically flat or negatively curved, then it is infinite in extent. Thus if the universe has a more-or-less uniform density, less than the critical density, then there must exist infinite mass. Is there something wrong with this argument?
The other editor claims that an infinitely massive universe would contradict the big bang. I don't think that's so either; again as I understand it, if you take a hyperbolic universe of uniform density and consistent with known astronomical facts, and run the equations backward in time, you still arrive at a singularity (infinite density) some finite distance into the past. -- Trovatore 07:46, 21 September 2006 (UTC)
The above discussion led me to observable universe, which had some rather odd claims when I got to it. It appeared to claim that the observable universe was the whole universe. Moreover, it didn't have any reference to the observable universe depending on the observer, which it seems to me it obviously must, just assuming that the universe is a connected 3-manifold. As I understand it, point B may be in point A's observable universe, and point C may be in point B's observable universe, but point C may not be in point A's observable universe. So a photon could get from point C to point B, but by that time, the expansion of the universe would have carried B out of A's observable universe, so the information could not then be passed to A.
But I do have a little difficulty thinking about just how to express it mathematically. Suppose for convenience that the universe is asymptotically flat, so it can be treated as R3. Is it accurate to say, in the above situation, that C is outside A's observable universe because the universal expansion means that it is moving faster than the speed of light, from A's point of view, but that B is moving slower than the speed of light from A's point of view, and C is moving slower than the speed of light from B's point of view? But then what happened to the usual relativistic addition of velocities? Is it just not possible to consider an inertial coordinate system from A's point of view that extends to C? -- Trovatore 07:46, 21 September 2006 (UTC)
You asked "But then what happened to the usual relativistic addition of velocities? Is it just not possible to consider an inertial coordinate system from A's point of view that extends to C?". The notions of "relativistic addition of velocities" and "inertial coordinate system" are part of special relativity and cannot be applied, without modification, to general relativitiy. Imagine a model in which the manifold is R4 with the metric which corresponds to a universe dominated by the cosmological constant. Then every particle has a horizon surrounding it which asymptotically (exponentially) approaches it as time goes to infinity. If you go far enough into the past, you can see the early history of any other particle. But any two dust particles, no matter how close to each other, will eventually get so far apart that light rays emitted from them heading toward each other cannot ever meet. JRSpriggs 09:17, 22 September 2006 (UTC)
Hi everyone,
Thljcl ( talk • contribs) has made several edits, which seem questionable to me, to articles such as kinetic energy, E=mc², mass and special relativity. These edits have a theme of removing indications that mass is a form of energy (which is correct, as far as I know). Can anyone have a look and check if they are legitimate? -- Meni Rosenfeld ( talk) 06:39, 22 September 2006 (UTC)
User:Thljcl has clarified in Talk:Kinetic energy that he means to say that every form of energy is mass, that is, mass and energy are the same thing. Isn't that a legitimate interpretaion? What should be done about it? -- Meni Rosenfeld ( talk) 06:59, 23 September 2006 (UTC)
Well, they're certainly different as far as calculations are concerned. However, conceptually they describe the same physical reality. 200 g, 18 P J and 1.961 N (assuming a constant g = 9.805 m/s2) all describe the same amount of pastrami. This, I think, means we should at least give some thought about the merits of said edits. -- Meni Rosenfeld ( talk) 11:15, 23 September 2006 (UTC)
Very well. SCZenz, please note that I did not say we should include his edits (in which case I would probably have been, indeed, wrong), but only that we should take a look and see if they contain anything salvageable - which I'm sure you did, and support your conclusion that there is none. Perhaps it's worth mentioning that the idea that potential energy is manifested as mass is new to me, which is why I've brought this issue up here.-- Meni Rosenfeld ( talk) 21:23, 23 September 2006 (UTC)
Now I'm confused. See here. -- Meni Rosenfeld ( talk) 05:10, 24 September 2006 (UTC)
Wortzman ( talk · contribs) aka 162.84.136.215 ( talk · contribs) has been adding blab on some bollocks called the "Gyroverse" to the Theory of everything article. He has done it 3 times (once under the IP address), and I have reverted all 3 times and warned them, but if I revert again, I am in violation of 3RR whereas he isn't (because of the IP). If anyone has the chance to keep an eye on the article... Byrgenwulf 13:56, 22 September 2006 (UTC)
I was in trim down mood and reduced the other efforts section. And noticing one of these overgrown templates, I've put Template:Theories of gravitation of TfD. -- Pjacobi 16:49, 22 September 2006 (UTC)
I noticed that the WP pages on scalar field theory were fairly disparate, with no coherent description or even agreement on conventions. So, I've created the new page Scalar field theory, which no longer just redirects to Scalar field. I've also changed the links on a number of physics pages which used to link to Scalar field, so that they now point to the new article (I've been fairly selective when doing this, i.e. linking pages which clearly mean to refer to scalar field theory, rather than the more general concept of the scalar field.)
There are two things I'd appreciate feedback on. First, there's still more work to do on the page, so help would be appreciated. But also, I'd wondered whether it now might now be worth blanking and redirecting this page on scalar field theory and this page on phi^4 theory.
I'm not sure about the latter just yet, because there are a few things on there that are not yet on the new page. However, I believe the parts that do overlap are now more coherently described. Perhaps the phi^4 page could be reserved for more detailed information on that theory, I'm not sure at the moment.
I've left relevant messages on the talk pages, but thought they might not be widely watched. All the best-- Jpod2 09:55, 23 September 2006 (UTC)
Hi everyone,
Photon is now a Featured Article candidate. If you like the article, please leave lots of Support votes there, so that the WikiProject will get another FA. Thanks! :D Willow 10:00, 23 September 2006 (UTC)
Non existing key experiment added to quantum mechanics in May 2006
Just one edit before, there was some "asdf"-vandalism
Recent changes patroller Beek man removed the "asdf"-vandalism, but considered the key experiment to be legit:
Pjacobi 20:12, 24 September 2006 (UTC)
Discouraging people from reverting vandalism would be a mistake. The only solution I see is for more people to do what I usually do -- I look at each individual change in the revision history since the last time I checked that article. Unfortunately, there are some articles (like Golden ratio) which are so active that I do not have enough time to do that. But in those cases, there are usually other people I trust who are watching them more closely. Also there are often changes which I cannot verify because they lie outside the scope of my knowledge. So I just have to hope that errors in such changes will be corrected by someone else. JRSpriggs 04:33, 26 September 2006 (UTC)
Some comments:
Pjacobi 07:26, 26 September 2006 (UTC)
I was thinking of creating an article on the Harmonic coordinate condition. See http://mathworld.wolfram.com/HarmonicCoordinates.html You-all do not seem to have any articles or categories which fit exactly. The closest thing I see is Category:Frames of reference. Is that the appropriate category for it? JRSpriggs 06:50, 26 September 2006 (UTC)
I found another category which may be more appropriate, to wit Category:Coordinate charts in general relativity. Yes, General covariance might be a good place to put material on harmonic coordinates and other coordinate choices. It is frequently said that a choice of coordinate system is the analogue for gravity of choosing a gauge in electromagnetism. But I am not sure that that is exactly right. Perhaps it might be more correct to say that the gauge of gravity is a choice of a "background" (non-physical) connection whose Riemann-Christoffel (curvature) tensor is zero everywhere. Then the gravitational force-field is the physical connection minus the background connection (and thus a tensor field). Does that make sense? JRSpriggs 07:59, 28 September 2006 (UTC)
Hi, in articles on particles, the background colour of info tables is a dark grey. This isn't too legible, so the photon article has been edited to use "lightgray" instead of "gray". Would it be OK to spread the change to all articles? If yes, I propose we change them all. -- Kjoon lee 06:54, 26 September 2006 (UTC)
I'm not going to argue and find consensus with Kentforbes ( talk · contribs · block log) whether electrolysing water, burning the hydrogen, and having a net energy gain in the process should be considered to be a perpetuum mobile. Nor do I intend to put a humble "cite needed" tag to the claim, that this Water fuel cell powered a car driven across the United States. I will simply revert until someone blocks me for 3RR violation.
If someone is in the mood to resolve the problem by other means, don't hesitate.
Pjacobi 08:46, 26 September 2006 (UTC)
Do you consider it a sane question, to be asked for in-line cites, for e.g. the statement two events happening in two different locations that occur simultaneously to one observer, may occur at different times to another observer at Special relativity? See Talk:Special relativity#GA Re-Review and In-line citations. -- Pjacobi 08:55, 26 September 2006 (UTC)
Wow, I'm currently embroiled in the GOOD article nonsense that is non-expert Wikipedians saying that articles like Hubble's Law aren't good because they only have two in-line citations. Yuck. I say we start our own Wikipedia project "Good science articles". We can make it part of Wikipedia:Scientific peer review. -- ScienceApologist 18:53, 26 September 2006 (UTC)
To see what happens when a non-physicist decides that there isn't enough inline references, look no further than the current state of redshift which, I might add, is probably over-inline-cited right now (if you can believe it). If you don't feel like routing through this article, I'll give you an example. An enterprising FA reviewer thought it wise to put a {{fact}} tag on a statement that amounts to the idea that Rayleigh scattering accounts for the sky being blue. -- ScienceApologist 20:32, 26 September 2006 (UTC)
Yes, this is also going on at Talk:String theory. This makes very little sense to me. It is something that I've occasionally tried to bring up on WT:V and elsewhere, and made very little headway. (I can't remember what initially got me worrying about this.) The attitude of the rest of the Wikipedia community is "Well, if it's in so many books, then it should be easy to find a reference." This all originated from legitimate worries that information in Wikipedia wasn't sufficiently verifiable, which is true, but like many policies, some people seem intent on pushing it to its bone-headed extreme.
Part of the problem is that a lot of information that is common knowledge to specialists (or even undergraduates in physics) is hard to tell from genuinely controversial statements. This only reinforces the need for some mechanism by which specialists (or WikiProjects) can bless content. – Joke 20:35, 26 September 2006 (UTC)
I have made a request regarding this issue here. -- ScienceApologist 21:03, 26 September 2006 (UTC)
My attempt to edit the in-line citation criterion to be saner here was immediately knee-jerk reverted because the old version supposedly "had consensus." I believe this is false.
If, as it appears, most of us here agree that my version was more sensible, I propose that we make our voices heard. This being a wiki, a very reasonable course of action is to revert the criterion once each. -- SCZenz 00:21, 27 September 2006 (UTC)
@Homestarmy: This is not Citizendium, what the "experts" say isn't the final decision on things. This is wrong for at least two reason:
Pjacobi 07:33, 27 September 2006 (UTC)
I've agressively tried to get this problem fixed, with some limited success. Now I need to cool off and ignore Wikipedia for a while. If it's really important, I'm sure others here can take up the banner from this point. -- SCZenz 02:12, 27 September 2006 (UTC)
(Originally in reply to Anville's comment at 13:03 27 September.) "Precedence" does not appear to have much weight, unless presented as a "guideline". Can we, by a consensus process, establish a proposal guideline for citations in science and mathematics articles, and then declare them to be a Wikipedia guideline, just as by some mysterious process there are notability guidelines for different kinds of topics? -- -- Lambiam Talk 21:59, 27 September 2006 (UTC)
I propose we just ignore the good articles page. GA used to be an extra step between A- and B-class; now that step has moved, from my reading, above A-class. They are not responsive to our concerns over at the GA criteria page.
So let's just use A- and B- and Stub- and Start-, which are criteria internal to our project. I do not think we need a new bureaucracy for identifying A-class articles. Let's just keep rating articles on a volunteer basis and trying to improve them, and discuss it here if an article is badly mis-rated.
We do need outside feedback, and lots of it, but I think the far older and less-rigid Wikipedia:Peer review is a better place to get it. -- SCZenz 14:57, 27 September 2006 (UTC)
Ah, that's worthy of a wistful sigh or two. I wrote a few paragraphs about my attitude towards this whole thing at Wikipedia_talk:Good_article_candidates#Can a compromise be found?. The gist of it is:
I'd appreciate any comments. – Joke 16:34, 27 September 2006 (UTC)
Please see Talk:Rietdijk-Putnam Argument. -- Pjacobi 09:31, 28 September 2006 (UTC)
Tatonzolo 07:47, 29 September 2006 (UTC)
Heim theory has been proposed for deletion. Comment as you see fit. Anville 13:49, 28 September 2006 (UTC)
Look what one editor is doing to science articles. Can we say, anti-science bias perhaps? -- ScienceApologist 21:51, 28 September 2006 (UTC)
This is apparently the future of Wikipedia: Lancaster County, Pennsylvania. It'll be a heck of a lot of fun to write for the project then. – Joke 13:07, 29 September 2006 (UTC)
11 references in a stub of three sentences :-) Count Iblis 18:33, 29 September 2006 (UTC)
Let's try to get people at WP:CITE to listen to us. We have a suggestion that this guideline include a statement to the effect that elementary facts should not be cited. I tried to qualify this with a statement of what things I think (and maybe others think) should be cited in science articles and what things should not (and why). Please read, comment, and modify this work here. -- ScienceApologist 05:50, 29 September 2006 (UTC)
![]() | This page is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
There is a problem which appears to afflict most of the articles on Special Relativity. They are not consistent with the International System of Units. Ultimately this is because you-all are using ct (i.e. meters) as the time coordinate rather than t (i.e. seconds). But it results in you having the wrong versions of the Minkowski metric, the momentum 4-vector, the velocity 4-vector, etc.. I cannot fix all of them myself because there are too many such articles and I am sure that I would encounter significant opposition from people who suffer from the mistaken prejudice that every component of a tensor must be in the same units. For a correct understanding of how to assign units to the components of a tensor see E.J.Post, Formal Structure of Electomagnetics: General Covariance and Electromagnetics, Dover Publications Inc. Mineola NY, 1962 reprinted 1997.
Even worse, some people do not seem to realize that one must distinguish between the covariant and contravariant versions of a tensor. JRSpriggs 07:49, 11 September 2006 (UTC)
Units are an unnecessary complication in physics. It's simpler to just put c = h-bar = G = 1 and stop arguing about this. If you want to express time in units of seconds then just convert it to seconds. There is no need to put the factor c in formulae just because people might use incompatible units for space and time. Count Iblis 16:40, 11 September 2006 (UTC)
For example, Four-momentum says
but I contend that it should say
and also
If (as SI units demand) we use t in seconds for time and give the spatial coordinates in meters, then the units of a component of a tensor should be (meter/second)^n times the units of the purely spatial components of the tensor where n is the number of covariant time indices minus the number of contravariant time indices of the component in question.
Is this merely a matter of convention? Yes, but so is the use of SI units. People need to use consistent conventions to avoid being confused and to get the right answers when doing calculations.
Why not use natural units? First, because they are not the standard which is generally used in society (i.e. SI units). Secondly, if c is left out of the equations, then people will have to figure out where to put it in when they convert units. If it is already there, they can just substitute in the appropriate value for the system of units they want to use, whether that value is "299,792,458" or "1" or "186,282.397" or whatever.
Is it merely a silly historical artifact that we use both meters and seconds? Not really. Human activities are conducted almost exclusively at speeds much lower than c. The units we use in everyday life should be such that they yield numerical values which are near one rather than many orders of magnitude off. That requires a different unit for time than for distance.
What you-all are doing currently is building a conversion of units into the process by which you apply your equations. But that makes no sense. Tensors are already designed to handle all such issues. Just let them do it. JRSpriggs 07:52, 12 September 2006 (UTC)
Count Iblis 16:53, 15 September 2006 (UTC)
Hi everyone,
Photon seems to be getting close to becoming a Featured Article. But we would really appreciate your suggestions on how to improve it before we submit it as an FA candidate. Please take a few minutes to review the article and give us your advice on whether it's ready to be an FA at Talk:Photon. Thanks muchly! :D Willow 19:21, 11 September 2006 (UTC)
Sort of. EmDrive. The keepers are already piling up at Wikipedia:Articles for deletion/EmDrive, so we have another of those pesky pages to look after. -- Pjacobi 16:43, 13 September 2006 (UTC)
Newton first published his remarkably concise and simple formalism about Nature in 1687. His three Laws of Motion turned out to be far ahead of their time, more accurate than the accuracy of experimental data available to Newton. More than three centuries later, after Classical Mechanics was taken to its climax, considered a dead science and resurrected once more, they remain the prototype of physical theories and high practical utility. More sophisticated reformulations of classical mechanics, while in many ways outstripping Newton's original formulation which seems almost childishly simple compared to the level of mathematical complexity inherent in these formalisms, still lose to Newton's Laws of Motion in terms of practical usefulness because of their failure to model systems with the dissipation approximation.
It is sad indeed, therefore, to see our article on this remarkable theory of Physics lie neglected. The level of exposition is suited to Children's Learning Library, not a serious encyclopedia. Nothing is mentioned about the significance of inertial reference frames. No reference is made to the interpretation of the first law of motion as a definition, no explanation is given why the first law must be considered independent of and preceding the second law. Detailed discussions are not provided about the validity of the third law in the context of classical electrodynamics. No mention at all of their reformulation without using the concept of force, depending on momentum and energy. Very important topics such as the role of Galilean relativity in Newtonian mechanics and the subsequent need to formulate the theory in terms of fiber bundles is absent.
My grasp of physics is not advanced enough to undertake these tasks without the fear of mistake, therefore I appeal to you to improve this article. The current state of the article, particularly in comparison with our articles on Lagrangian Mechanics, Hamiltonian Mechanics, Hamilton-Jacobi equation etc, gives the distinct impression that the contributors considered NLM to be a theory without any mathematical beauty or elegance behind it, something only children do. This situation must be rectified, most importantly for students just learning the theory who may visit our pages for an extended perspective and academics who may have lost sight of the theories remarkable power when faced with the cacophony of alternative theories. Loom91 11:53, 14 September 2006 (UTC)
Hi everyone,
Photon is now in peer review, in preparation for its Featured Article candidacy. Please take a few minutes to review the article and give us your advice on how to prepare it to be Featured — thanks! :D Willow 11:31, 15 September 2006 (UTC)
As per #Automatic adding of project banner to articles in Category:Physics above, I've put together an initial list of physics categories for auto-tagging with the project banner. The list is currently located at User:Mike Peel/Physics categories. I'd appreciate people's help at trimming down the list to only those appropriate to physics (my selection method wasn't that accurate), as well as adding any that I've missed. I'd also like to pose a question: does this Wikiproject also cover astronomy, or should a new wikiproject be established to cover that? Thanks. Mike Peel 18:38, 16 September 2006 (UTC)
Someone's theory of everything, "licensed" under the GPL!; this one says we all live inside a hydrogen molecule. The AfD is here...it started quite well, but now the usual accusations of being the people who burnt Giordano Bruno are coming up. Oh dear. Byrgenwulf 11:13, 18 September 2006 (UTC)
I've recently noticed User:Kingbotk's application of the Template:WPBiography template to articles within the living persons category. Would it be worth me approaching him to ask if he could do something similar with the articles in Category:Physics? Additionally, it seems that he can classify articles within the appropriate stubs section as class=stub, which also may be worth doing. The process would not be able to classify the articles by quality or class, excluding the stubs, so although they would appear in Wikipedia:Version 1.0 Editorial Team/Physics articles by quality, they would be marked as unclassified. Mike Peel 13:53, 21 August 2006 (UTC)
Another approach to getting this done would be to make a request at Wikipedia:Bot requests. What do people think - is this worth doing? Mike Peel 22:06, 29 August 2006 (UTC)
<-- Me again! My plugin has come on in leaps and bounds (see User:Kingbotk/Plugin) and I think the version I'm testing now ready for release later this evening will interest you.
The plugin can tag talk pages with WikiProject banners. If the template doesn't exist on the page, it creates one; if it exists under a different (redirected) name, it renames it to the "official" name. Existing parameters which are already on the page are retained, and new ones added which have been selected by the operator. If the article is a redlink (it sometimes happens that articles get deleted after the list has been built but before the bot gets there) it skips it. If the talk page template is misconfigured it skips and logs it. The beauty of all this is that it happens transparently - drop the plugin file into the AWB folder, click a few checkboxes, and off you go. A recent version also added support for reviewing and assessing articles manually, but I'm not aware that anybody's used that feature in anger yet.
Until now I've only supported specific, very complex templates ({{ WPBiography}}, {{ WPMILHIST}} and {{ WP Australia}}). The changes I've just been working on allow the plugin to work with the template of any WikiProject, provided it has a class= parameter (which yours does). Ideally, the template should have needs-infobox=, attention= and auto= parameters too (you can steal some code for these from {{ WPBiography}}). I call these templates " Generic WikiProject templates".
Anyway! To get to the end of a long story, I've just had my bot tag Category:Australian physicists with 3 templates, WPBIO, WPAUS, and "Physics generic template". Example diff: [1] Example where some templates already existed and only Physics got added: [2]
Hope that helps. Any more questions you can ask me here as I'll keep this page watchlisted for a while longer. -- kingboyk 18:08, 18 September 2006 (UTC)
John Baez has posted a public letter from Greg Egan about New Scientist magazine at The n-Category Café. Since the issue of this magazine's reliability (and how much "notability" its august aegis actually confers) has come up here a few times, I figured I should post a link. Quoting the first few paragraphs from Egan:
I like the word gobsmacked. Anville 17:46, 19 September 2006 (UTC)
Hey physics guruz, a couple questions have come up in recent editing, and I thought I'd get some expert advice. They both relate in some way to the possibility of physically real infinities. One is whether there is a consensus that the universe (the whole universe, not just the observable universe) has finite mass. The other is about just what "observable universe" means. I'll break them down into subsections for ease of discussion. -- Trovatore 07:46, 21 September 2006 (UTC)
This discussion came up at infinite monkey theorem. An editor there had made a calculation (a bit OR-ish, but that's not important right now) about how long it would take to get a certain part of Hamlet's famous soliloquy if every atom in the universe were a monkey, or something along those lines. He claimed that this means the whole universe, not just the observable universe.
I doubt that any such thing is known. As I understand it, if the universe is asymptotically flat or negatively curved, then it is infinite in extent. Thus if the universe has a more-or-less uniform density, less than the critical density, then there must exist infinite mass. Is there something wrong with this argument?
The other editor claims that an infinitely massive universe would contradict the big bang. I don't think that's so either; again as I understand it, if you take a hyperbolic universe of uniform density and consistent with known astronomical facts, and run the equations backward in time, you still arrive at a singularity (infinite density) some finite distance into the past. -- Trovatore 07:46, 21 September 2006 (UTC)
The above discussion led me to observable universe, which had some rather odd claims when I got to it. It appeared to claim that the observable universe was the whole universe. Moreover, it didn't have any reference to the observable universe depending on the observer, which it seems to me it obviously must, just assuming that the universe is a connected 3-manifold. As I understand it, point B may be in point A's observable universe, and point C may be in point B's observable universe, but point C may not be in point A's observable universe. So a photon could get from point C to point B, but by that time, the expansion of the universe would have carried B out of A's observable universe, so the information could not then be passed to A.
But I do have a little difficulty thinking about just how to express it mathematically. Suppose for convenience that the universe is asymptotically flat, so it can be treated as R3. Is it accurate to say, in the above situation, that C is outside A's observable universe because the universal expansion means that it is moving faster than the speed of light, from A's point of view, but that B is moving slower than the speed of light from A's point of view, and C is moving slower than the speed of light from B's point of view? But then what happened to the usual relativistic addition of velocities? Is it just not possible to consider an inertial coordinate system from A's point of view that extends to C? -- Trovatore 07:46, 21 September 2006 (UTC)
You asked "But then what happened to the usual relativistic addition of velocities? Is it just not possible to consider an inertial coordinate system from A's point of view that extends to C?". The notions of "relativistic addition of velocities" and "inertial coordinate system" are part of special relativity and cannot be applied, without modification, to general relativitiy. Imagine a model in which the manifold is R4 with the metric which corresponds to a universe dominated by the cosmological constant. Then every particle has a horizon surrounding it which asymptotically (exponentially) approaches it as time goes to infinity. If you go far enough into the past, you can see the early history of any other particle. But any two dust particles, no matter how close to each other, will eventually get so far apart that light rays emitted from them heading toward each other cannot ever meet. JRSpriggs 09:17, 22 September 2006 (UTC)
Hi everyone,
Thljcl ( talk • contribs) has made several edits, which seem questionable to me, to articles such as kinetic energy, E=mc², mass and special relativity. These edits have a theme of removing indications that mass is a form of energy (which is correct, as far as I know). Can anyone have a look and check if they are legitimate? -- Meni Rosenfeld ( talk) 06:39, 22 September 2006 (UTC)
User:Thljcl has clarified in Talk:Kinetic energy that he means to say that every form of energy is mass, that is, mass and energy are the same thing. Isn't that a legitimate interpretaion? What should be done about it? -- Meni Rosenfeld ( talk) 06:59, 23 September 2006 (UTC)
Well, they're certainly different as far as calculations are concerned. However, conceptually they describe the same physical reality. 200 g, 18 P J and 1.961 N (assuming a constant g = 9.805 m/s2) all describe the same amount of pastrami. This, I think, means we should at least give some thought about the merits of said edits. -- Meni Rosenfeld ( talk) 11:15, 23 September 2006 (UTC)
Very well. SCZenz, please note that I did not say we should include his edits (in which case I would probably have been, indeed, wrong), but only that we should take a look and see if they contain anything salvageable - which I'm sure you did, and support your conclusion that there is none. Perhaps it's worth mentioning that the idea that potential energy is manifested as mass is new to me, which is why I've brought this issue up here.-- Meni Rosenfeld ( talk) 21:23, 23 September 2006 (UTC)
Now I'm confused. See here. -- Meni Rosenfeld ( talk) 05:10, 24 September 2006 (UTC)
Wortzman ( talk · contribs) aka 162.84.136.215 ( talk · contribs) has been adding blab on some bollocks called the "Gyroverse" to the Theory of everything article. He has done it 3 times (once under the IP address), and I have reverted all 3 times and warned them, but if I revert again, I am in violation of 3RR whereas he isn't (because of the IP). If anyone has the chance to keep an eye on the article... Byrgenwulf 13:56, 22 September 2006 (UTC)
I was in trim down mood and reduced the other efforts section. And noticing one of these overgrown templates, I've put Template:Theories of gravitation of TfD. -- Pjacobi 16:49, 22 September 2006 (UTC)
I noticed that the WP pages on scalar field theory were fairly disparate, with no coherent description or even agreement on conventions. So, I've created the new page Scalar field theory, which no longer just redirects to Scalar field. I've also changed the links on a number of physics pages which used to link to Scalar field, so that they now point to the new article (I've been fairly selective when doing this, i.e. linking pages which clearly mean to refer to scalar field theory, rather than the more general concept of the scalar field.)
There are two things I'd appreciate feedback on. First, there's still more work to do on the page, so help would be appreciated. But also, I'd wondered whether it now might now be worth blanking and redirecting this page on scalar field theory and this page on phi^4 theory.
I'm not sure about the latter just yet, because there are a few things on there that are not yet on the new page. However, I believe the parts that do overlap are now more coherently described. Perhaps the phi^4 page could be reserved for more detailed information on that theory, I'm not sure at the moment.
I've left relevant messages on the talk pages, but thought they might not be widely watched. All the best-- Jpod2 09:55, 23 September 2006 (UTC)
Hi everyone,
Photon is now a Featured Article candidate. If you like the article, please leave lots of Support votes there, so that the WikiProject will get another FA. Thanks! :D Willow 10:00, 23 September 2006 (UTC)
Non existing key experiment added to quantum mechanics in May 2006
Just one edit before, there was some "asdf"-vandalism
Recent changes patroller Beek man removed the "asdf"-vandalism, but considered the key experiment to be legit:
Pjacobi 20:12, 24 September 2006 (UTC)
Discouraging people from reverting vandalism would be a mistake. The only solution I see is for more people to do what I usually do -- I look at each individual change in the revision history since the last time I checked that article. Unfortunately, there are some articles (like Golden ratio) which are so active that I do not have enough time to do that. But in those cases, there are usually other people I trust who are watching them more closely. Also there are often changes which I cannot verify because they lie outside the scope of my knowledge. So I just have to hope that errors in such changes will be corrected by someone else. JRSpriggs 04:33, 26 September 2006 (UTC)
Some comments:
Pjacobi 07:26, 26 September 2006 (UTC)
I was thinking of creating an article on the Harmonic coordinate condition. See http://mathworld.wolfram.com/HarmonicCoordinates.html You-all do not seem to have any articles or categories which fit exactly. The closest thing I see is Category:Frames of reference. Is that the appropriate category for it? JRSpriggs 06:50, 26 September 2006 (UTC)
I found another category which may be more appropriate, to wit Category:Coordinate charts in general relativity. Yes, General covariance might be a good place to put material on harmonic coordinates and other coordinate choices. It is frequently said that a choice of coordinate system is the analogue for gravity of choosing a gauge in electromagnetism. But I am not sure that that is exactly right. Perhaps it might be more correct to say that the gauge of gravity is a choice of a "background" (non-physical) connection whose Riemann-Christoffel (curvature) tensor is zero everywhere. Then the gravitational force-field is the physical connection minus the background connection (and thus a tensor field). Does that make sense? JRSpriggs 07:59, 28 September 2006 (UTC)
Hi, in articles on particles, the background colour of info tables is a dark grey. This isn't too legible, so the photon article has been edited to use "lightgray" instead of "gray". Would it be OK to spread the change to all articles? If yes, I propose we change them all. -- Kjoon lee 06:54, 26 September 2006 (UTC)
I'm not going to argue and find consensus with Kentforbes ( talk · contribs · block log) whether electrolysing water, burning the hydrogen, and having a net energy gain in the process should be considered to be a perpetuum mobile. Nor do I intend to put a humble "cite needed" tag to the claim, that this Water fuel cell powered a car driven across the United States. I will simply revert until someone blocks me for 3RR violation.
If someone is in the mood to resolve the problem by other means, don't hesitate.
Pjacobi 08:46, 26 September 2006 (UTC)
Do you consider it a sane question, to be asked for in-line cites, for e.g. the statement two events happening in two different locations that occur simultaneously to one observer, may occur at different times to another observer at Special relativity? See Talk:Special relativity#GA Re-Review and In-line citations. -- Pjacobi 08:55, 26 September 2006 (UTC)
Wow, I'm currently embroiled in the GOOD article nonsense that is non-expert Wikipedians saying that articles like Hubble's Law aren't good because they only have two in-line citations. Yuck. I say we start our own Wikipedia project "Good science articles". We can make it part of Wikipedia:Scientific peer review. -- ScienceApologist 18:53, 26 September 2006 (UTC)
To see what happens when a non-physicist decides that there isn't enough inline references, look no further than the current state of redshift which, I might add, is probably over-inline-cited right now (if you can believe it). If you don't feel like routing through this article, I'll give you an example. An enterprising FA reviewer thought it wise to put a {{fact}} tag on a statement that amounts to the idea that Rayleigh scattering accounts for the sky being blue. -- ScienceApologist 20:32, 26 September 2006 (UTC)
Yes, this is also going on at Talk:String theory. This makes very little sense to me. It is something that I've occasionally tried to bring up on WT:V and elsewhere, and made very little headway. (I can't remember what initially got me worrying about this.) The attitude of the rest of the Wikipedia community is "Well, if it's in so many books, then it should be easy to find a reference." This all originated from legitimate worries that information in Wikipedia wasn't sufficiently verifiable, which is true, but like many policies, some people seem intent on pushing it to its bone-headed extreme.
Part of the problem is that a lot of information that is common knowledge to specialists (or even undergraduates in physics) is hard to tell from genuinely controversial statements. This only reinforces the need for some mechanism by which specialists (or WikiProjects) can bless content. – Joke 20:35, 26 September 2006 (UTC)
I have made a request regarding this issue here. -- ScienceApologist 21:03, 26 September 2006 (UTC)
My attempt to edit the in-line citation criterion to be saner here was immediately knee-jerk reverted because the old version supposedly "had consensus." I believe this is false.
If, as it appears, most of us here agree that my version was more sensible, I propose that we make our voices heard. This being a wiki, a very reasonable course of action is to revert the criterion once each. -- SCZenz 00:21, 27 September 2006 (UTC)
@Homestarmy: This is not Citizendium, what the "experts" say isn't the final decision on things. This is wrong for at least two reason:
Pjacobi 07:33, 27 September 2006 (UTC)
I've agressively tried to get this problem fixed, with some limited success. Now I need to cool off and ignore Wikipedia for a while. If it's really important, I'm sure others here can take up the banner from this point. -- SCZenz 02:12, 27 September 2006 (UTC)
(Originally in reply to Anville's comment at 13:03 27 September.) "Precedence" does not appear to have much weight, unless presented as a "guideline". Can we, by a consensus process, establish a proposal guideline for citations in science and mathematics articles, and then declare them to be a Wikipedia guideline, just as by some mysterious process there are notability guidelines for different kinds of topics? -- -- Lambiam Talk 21:59, 27 September 2006 (UTC)
I propose we just ignore the good articles page. GA used to be an extra step between A- and B-class; now that step has moved, from my reading, above A-class. They are not responsive to our concerns over at the GA criteria page.
So let's just use A- and B- and Stub- and Start-, which are criteria internal to our project. I do not think we need a new bureaucracy for identifying A-class articles. Let's just keep rating articles on a volunteer basis and trying to improve them, and discuss it here if an article is badly mis-rated.
We do need outside feedback, and lots of it, but I think the far older and less-rigid Wikipedia:Peer review is a better place to get it. -- SCZenz 14:57, 27 September 2006 (UTC)
Ah, that's worthy of a wistful sigh or two. I wrote a few paragraphs about my attitude towards this whole thing at Wikipedia_talk:Good_article_candidates#Can a compromise be found?. The gist of it is:
I'd appreciate any comments. – Joke 16:34, 27 September 2006 (UTC)
Please see Talk:Rietdijk-Putnam Argument. -- Pjacobi 09:31, 28 September 2006 (UTC)
Tatonzolo 07:47, 29 September 2006 (UTC)
Heim theory has been proposed for deletion. Comment as you see fit. Anville 13:49, 28 September 2006 (UTC)
Look what one editor is doing to science articles. Can we say, anti-science bias perhaps? -- ScienceApologist 21:51, 28 September 2006 (UTC)
This is apparently the future of Wikipedia: Lancaster County, Pennsylvania. It'll be a heck of a lot of fun to write for the project then. – Joke 13:07, 29 September 2006 (UTC)
11 references in a stub of three sentences :-) Count Iblis 18:33, 29 September 2006 (UTC)
Let's try to get people at WP:CITE to listen to us. We have a suggestion that this guideline include a statement to the effect that elementary facts should not be cited. I tried to qualify this with a statement of what things I think (and maybe others think) should be cited in science articles and what things should not (and why). Please read, comment, and modify this work here. -- ScienceApologist 05:50, 29 September 2006 (UTC)