User talk:JRSpriggs/Archive 3

This is the archive file "User talk:JRSpriggs/Archive 3".

Reverting Your Reversion to Ordinal Notation

I understand that narrower notion might be how the term ordinal notation is used in proof theory and the like but I'm writing up my thesis right now in computability theory and I can quickly find you several references that use the term ordinal notation to refer to Kleene's O since that is standard terminology in my field. If you wish to further clarify that in SOME areas ordinal notation refers to the specific notion you mention go ahead but standard usage in one area shouldn't be deleted just because that isn't the way you use the term. Also the obviously NPOV violation about Kleene's O needs to stay out of the article.

Just what I found in 5 minutes: "Hyperarithmetical Index Sets In Recursion Theory" by Stephen Lempp "Constructive Ordinal Notation Systems" by Fredrick Gass "Theory of Recursive Functions and Effective Computability" by Hartley Rogers. (p205)

The last one is particularly definitive as he doesn't just use the term but straight out defines what it means to be an ordinal notation, credits the notion to Kleene and the book is considered one of THE reference books for recursion theory. Logicnazi (talk) 12:21, 6 March 2008 (UTC)

F.Y.I. My thesis was on ordinal notations. I will respond further at Talk:Ordinal notation. JRSpriggs (talk) 05:27, 7 March 2008 (UTC)

Since your thesis was on ordinal notations, you might be able to answer the following question: can you recommend a "standard" system of ordinal notations for wikipedia to use for impredicative ordinals? R.e.b. (talk) 21:13, 8 March 2008 (UTC)

To R.e.b.: Thank you for your work on articles about large countable ordinals and ordinal notations. I am not in touch with the latest developments. I worked on my thesis thirty years ago. As of that time, there was no standard set of notations. And as I indicated on the talk page, "...no scheme of ordinal notations could include notations for all recursive ordinals without also either: including some "notations" for things which are not ordinals (types of pseudo-well-orders); or being non-effective (non-recursive) and thus not being usable for communication by human beings.". This implies that no standard is possible for the larger recursive ordinals.

I get the impression from your edits that you know more than I do about this subject (except for my own original and unpublished system of notations). The best reference I have in my possession is Larry W. Miller's "Normal functions and constructive ordinal notations". JRSpriggs (talk) 08:52, 10 March 2008 (UTC)

Mass-energy

While it is certainly your right to undo changes you think are "wrong and misleading" in general relativity, please note that the article is currently undergoing peer review, and that the change in question was in direct response to a reviewer's request. It would be very helpful if you could lay out your reasons of reverting the change on the review page. Otherwise, the reviewer might well wonder why a change that I claimed had been made is suddenly not there any more. Markus Poessel (talk) 01:12, 9 April 2008 (UTC)

replacement/collection

I saw you rephrased the axiom names at the ZFC article. Kunen does call that axiom "replacement", so there may be some confused comments on the talk page. My personal opinion is that it's a losing battle to try to use the Right Word for ZFC axioms, because the literature is hopelessly contradictory about the terms replacement/collection/bounding and specification/selection/comprehension. But I appreciate that other people may be more eager for precise terminology. Anyway, I have no plans of changing the terms back, since that would just prolong this very minor issue. — Carl (CBM · talk) 13:48, 10 April 2008 (UTC)

Kilogram v.s. volt

JRSpriggs, can you help me out here? Note the first paragraph of the Kilogram article, here. Of all the SI units of meausure, those last few sentences of that paragraph don’t mention the volt because I left it out on purpose and left a short editors note explaining why—the kilogram appears once in the numerator and denominator of the formula describing the volt (V = W⁄A). Random832 changed it after concluding (erroneously I believe) that the volt would be affected by a change in the kilogram. Well, as you know, a volt is defined by the BIPM as a W/A. Here’s a short nutshell of it all.

• V = W⁄A
  
• W = J⁄S = J·s^–1
  
• J = N·m
  
• N = m·kg·s^–2
  
• The second and the meter are the other SI base units (the ampere being the first) but I won’t bother with them since we all know what they are and they are immaterial to this discussion.

Thus, we can define the volt in all the following equivalencies:

V = W⁄A = J·s^–1⁄A = (N·m)·s^–1⁄A = (m·kg·s^–2)·m·s^–1⁄A = (m·kg·s^–2)·m·s^–1⁄K · 2×10⁻⁷ N = (m·kg·s^–2)·m·s^–1⁄K · 2×10⁻⁷ (m·kg·s^–2)

My conclusion of course is that since the newton (and therefore the kilogram) appear only once each in the numerator and denominator, the value of the volt is unaffected by changes in the kilogram. Details are here on Talk:Kilogram and my full reasoning is here. Can you help me out here? Greg L (my talk) 00:53, 13 April 2008 (UTC)

To Greg_L: From briefly looking at the talk page, I think that you have already realized that you were mistaken. The Ampere is proportional to the square-root of the kilogram. Thus the Volt is also proportional to the square-root of the kilogram. Sorry. JRSpriggs (talk) 06:32, 13 April 2008 (UTC)

Prod and AfD

Actually, it may make sense to have all three {{db}}, {{prod}}, and {{AfD}} on the same article. In Dwyer function, I brought the AfD because an editor was disputing the prod, and might actually have gotten around to removing it. But, if you want to remove the Prod, I really can't object. — Arthur Rubin (talk) 01:47, 23 April 2008 (UTC)

We both believe that that editor did not want the PROD to go forward and cause deletion on Friday. Apparently, he failed to remove it because he does not yet understand our system. And he was making attempts to improve the article in the hope of saving it. So I removed the PROD for him.

I also feel that having more than one of those templates on the article at the same time is an abuse of the process. People have a hard enough time understanding even one of them. Being confronted with two or three simultaneously just makes it more difficult for them to figure out what they should do. And why waste people's time with an AfD until the PROD is gone? Anyhow, doing both seems like double jeopardy to me. JRSpriggs (talk) 02:04, 23 April 2008 (UTC)

I prefer to have the entire Wikipedia:walled garden on approximately the same schedule. The professor went to AfD, so I felt his function should also. Note that, although created by the same author, the equation is being protected by a student, so he might not be aware of the other article. — Arthur Rubin (talk) 02:43, 23 April 2008 (UTC)

I understand and agree with your desire to finish this process, but my reservations remain about multiple templates. By the way, could it be that the professor and his student are the same person? Especially since both are named "John". JRSpriggs (talk) 02:53, 23 April 2008 (UTC)

I don't think so. They seem to have different writing styles, and the student has a personal web site corresponding to the name of another co-author of one of the papers. If they're the same, then it would seem there's fraud going on outside of Wikipedia in the related sites. — Arthur Rubin (talk) 12:40, 23 April 2008 (UTC)

Yeah, one's photograph is of an middle-aged man, the other of a teenage boy. JRSpriggs (talk) 13:30, 23 April 2008 (UTC)

Brent's method

Hello, Could you please take a look at a question I asked on Talk:Brent's method? Thanks a lot for your help. laug (talk) 04:32, 14 May 2008 (UTC)

Please see my answer there. JRSpriggs (talk) 19:59, 14 May 2008 (UTC)

Regarding your reversions of the term "G-unit" in Gravitational constant

I have the page on my watchlist and noticed this slow-pace semi-editwar and would like to point out that perhaps discussing the changes with the IP address would help to either stop this from happening or come to agreement of it's addition. And also, please remember that if you revert the user more that three times in 24 hours you are liable to be blocked (WP:3RR) and that civility is a must.  Atyndall93 | talk  10:48, 23 May 2008 (UTC)

I am well aware of the 3RR rule and I am nowhere near violating it in this case. I have only reverted that change twice and the second reversion was more than 42 hours after the first. Do you have any evidence that that "G-unit" is actually used to mean "gravitational constant"?

It just seems like vandalism (and possibly spam advertising the G-Unit band) to me. Notice that (so far at least) user 152.1.53.8 (talk · contribs) has only two edits to his name, both to the same effect. This is common among a certain class of vandal.

By the way, I have not said anything uncivil to him; I just reverted him with "rvv" as the edit summary in the first case and no edit summary in the second case. You are mistaken in thinking that I was uncivil to you earlier. JRSpriggs (talk) 18:27, 23 May 2008 (UTC)

I am also aware that your two reversions are spaced far apart, my idea was that the vandal would attempt to perform that addition more that four times in a day and you would revert it, thus violating 3RR and potentially getting yourself blocked. A quick Google Books search turned up a few mentions of the term [1] (but this is probably just coming from the term G being paired with unit, not necessarily making it a colloquial) which may explain why this user tried to add the term to the article. I know that you have not been uncivil to this user, but sometimes when editors become frustrated, they can take their anger out on the newbies and bite them. In regards to your response to me on gravitational constant, the past is past, but please keep in mind in the future that what may not be perceived as an insult to yourself, may be perceived as one by the recipient ("Please do not edit articles which you know nothing about" may seem like a simple request to some [Me] but to someone with a hot head, it may be seen as an insult to their intelligence because you have made such a statement on one edit alone).  Atyndall93 | talk  02:37, 24 May 2008 (UTC)

As you say, these examples appear to be merely accidental — a "g" followed by a "unit" having no connection to each other. And they have no relationship to the gravitational constant in any case.

A truthful and relevant comment should not be construed as an insult.

However, unnecessary "advice" or "corrections", especially if mistaken, may be insulting. JRSpriggs (talk) 21:21, 24 May 2008 (UTC)

zero to the zero

I don't know if you were around last time this came up. I wanted to make sure you know that I really don't care how 0^0 is, or should be, defined. I use the 0^0 = 1 rule routinely, like everyone else does. My concern is just to get an article that presents the whole picture about 0^0, rather than only one aspect. So I am concerned with how 0^0 is treated in calculus and complex analysis in addition to discrete mathematics. I think that the exponentiation article currently does a pretty decent job of describing the conventions used in practice. The issue on the empty product article is just that I don't agree with flat statements "0^0 = 1" that ignore context. I am perfectly happy with statements like "When it represents an empty product, 0^0 is always taken to be 1." — Carl (CBM · talk) 11:05, 13 June 2008 (UTC)

Countable sets

To JRSpriggs:

I believe that the reason you had for deleting what I wrote (a topological proof of the uncountability of the real numbers) is invalid. If you know what topology is, you wouldn't have called it 'incompetent' in the first place. Please see the link provided:

topology

Topology Expert (talk) 09:00, 16 June 2008 (UTC)

There is also the discussion of this topic on my talk page. Perhaps, to avoid duplication, we can continue this there (if you have anything to add). Oded (talk) 16:56, 16 June 2008 (UTC)

Dear JRSpriggs,

You said on the talk page of countable set that the proof I gave for the uncountability of the reals is 'incorrect'. I am afraid it is correct as several people may have told you. You also said that you have limited knowledge of topology. If this is true then don't delete something that contains topology; in fact avoid it. I find it quite surprising that someone will say that a proof is incompetent without even knowing what the proof is about. This is why I feel obliged to revert your edit and if you plan to revert it back, please first of all discuss the issue on my talk page, User talk:Topology Expert. However, I am highly doubtful that this proof is wrong if you want to discuss it I will.

Topology Expert (talk) 10:23, 20 June 2008 (UTC)

intro to systolic geometry

Hi,

Thanks for your edit to introduction to systolic geometry, I think it goes in the right direction. Unfortunately, User:Loom91 did not like it, and deleted the Introduction template. Now I am glad he is interested in systolic geometry but this is already the third time he deleted the template. If wikipedia values input from experts I think there should be policy guidelines in such a situation. Katzmik (talk) 12:19, 25 June 2008 (UTC)

Inaccessible cardinal

Dear JRSpriggs, why did you remove the anon edit on Godel's second incompleteness theorem?Kope (talk) 06:15, 18 July 2008 (UTC)

The sentence I removed from Inaccessible cardinal said "Therefore, the existence of an inaccessible cardinal is unprovable in ZFC, for if said existence was provable in ZFC, then ZFC would be capable of proving itself consistent, in violation of Gödel's Second Incompleteness Theorem.". This sentence is unnecessary given the information available in the next paragraph. More importantly, this sentence makes an invalid inference — ZFC being inconsistent is not (known to be) a violation of Gödel's incompleteness theorems, so you cannot thereby infer that the existence of an inaccessible cardinal is unprovable in ZFC. In fact, if you could show that, then ZFC would be inconsistent by Gödel's theorem. JRSpriggs (talk) 12:11, 18 July 2008 (UTC)

Wait. "Con(ZFC)implies Con(ZFC+no inacc)" and "Con(ZFC) does not imply Con(ZFC+inacc)(unless ZFC is contradictory)" are two totally different statements. Kope (talk) 16:40, 18 July 2008 (UTC)

Now you have lost me — what is the connection between those two sentences and what was being talked about earlier?

"Con(ZFC)implies Con(ZFC+no inacc)" is true and is, essentially, the same as the last sentence in the second paragraph of Inaccessible cardinal#Models and consistency. It is most of what is needed to justify the statement "Therefore, inaccessible cardinals are a type of large cardinal." which is the last sentence of the first paragraph.

"Con(ZFC) does not imply Con(ZFC+inacc)(unless ZFC is contradictory)" is equivalent to saying "Con(ZFC) => Con(ZFC+Con(ZFC)+ not Con(ZFC+inacc))" which implies "not Con(ZFC)" which is hopefully false. JRSpriggs (talk) 17:21, 18 July 2008 (UTC)

Sorry, I became confused. I actually crossed out my notes, can't that be seen? Kope (talk) —Preceding comment was added at 17:46, 18 July 2008 (UTC)

The anon contribution was stylistically imperfect but generally correct; I'm not sure it needed to appear just there, though, so I don't seriously object to its removal. However I see JR's objection to it as coming from a fundamentally unsustainable epistemology -- you can't equate knowledge with provability in ZFC. If ZFC is reliable then it must be consistent, whereas if it's unreliable then we can't take its theorems to be known. For most purposes it is reasonable to say we do know that you can't prove in ZFC that there exists an inaccessible, even though of course that non-provability statement is not itself a theorem of ZFC. --Trovatore (talk) 18:24, 18 July 2008 (UTC)

To Kope: We had an edit conflict. When I finished writing my reply, I discovered that you had crossed out your message. I decided to post my message anyway since I had gone to all the trouble of writing it. You may ignore my message, if it does not tell you anything which you do not already know.

My larger point is that you should be careful to avoid saying that anything cannot be proved, unless you make it conditional on some hypothesis which is adequate to show that fact.

To Trovatore: I disagree with your epistemology. You are saying that we can somehow know more about formal systems like ZFC than what can be proven within those systems. Since those systems already incorporate all our known valid means of acquiring knowledge of higher mathematics, that is unlikely. If you find another way, let me know.

To say that ZFC must be consistent because we have not yet found an inconsistency in it amounts to accepting as a rule of inference that ${\frac {\forall n<T\lnot (n\,\,\operatorname {proves} (0=1))}{\forall n\lnot (n\,\,\operatorname {proves} (0=1))}}$ for some sufficiently large T. This is invalid and can be proven to lead to contradictions.

To say that ZFC (in its entirety) must be consistent because we need it to be consistent is just wishful thinking. JRSpriggs (talk) 08:20, 19 July 2008 (UTC)

If you don't accept that we know ZFC is consistent, then why should you accept that we know that the consequences of ZFC are true?

I think you are demanding too much from the word know. The sort of apodeictic knowledge that the ancients wanted from mathematics simply does not exist, in mathematics or anywhere else. We "know" that ZFC is consistent in a sense similar to the way we "know" other scientific claims -- it's falsifiable and has not been falsified, fits into an explanatory framework, etc etc. (Of course the explanatory framework is not simply that ZFC is consistent, but that it's actually true.) --Trovatore (talk) 08:44, 19 July 2008 (UTC)

I must apologize. The removed argument shows that Con(ZFC) does not imply Con(ZFC+IC) (unless trivially), so the consistency strength of ZFC+IC is larger than that of ZFC. This is stronger than the statement that ZFC does not imply ZFC+IC. This is a well known remark in set theory, appears, e.g., on p. 19 of A. Kanamori: The Higher Infinite. All the best. Kope (talk) 08:34, 19 July 2008 (UTC)

surface transport

Hi,

I adjusted the section on Riemannian connections at differential geometry of surfaces to fit better with the case of surfaces. Please take a look. Katzmik (talk) 10:39, 20 August 2008 (UTC)

Katzmik, thank you for improving the article. JRSpriggs (talk) 15:28, 20 August 2008 (UTC)

Well, user mathsci should certainly get a lot of the credit for developing the page. I have the impression he may have already moved most of the material I deleted to an alternative page. Katzmik (talk) 08:35, 21 August 2008 (UTC)

Thanks for heads-up

It was all in there once, but somebody or other deleted it. I'll see if I can't extract it from the archives and make further clarifications as appropriate.—PaulTanenbaum (talk) 20:34, 29 August 2008 (UTC)

I've added an explanation that I hope will scratch people's itch. On a bigger point, though, that explanation now links to a moderately complete article that I've finally gotten around to producing on set notation. I'd appreciate any comments you might have on both of these efforts.—PaulTanenbaum (talk) 16:32, 30 August 2008 (UTC)

Set notation#See also

I woulda included Set-builder notation but it was already mentioned in the body of the article. I thought that "See also" was intended for add'l stuff that hadn't yet been mentioned anywhere else. If that understanding is off, then I could add some more to this one.—PaulTanenbaum (talk) 14:56, 31 August 2008 (UTC)

I do not pay much attention to that particular "rule" since I do not see how it hurts to have a repeated link. In some cases (not this one), I think it is necessary to put the link into "See also" even though it is already in the text because the link in the text is hard to find or does not use the same word(s). JRSpriggs (talk) 15:04, 31 August 2008 (UTC)

non-standard uniform continuity

Hi, Thanks for your comment. I guess I only meant that the non-standard definition is simpler in the sense of Kolmogorov complexity :) but seriously, doesn't uniform continuity say that if the points are close then their images are close? Katzmik (talk) 12:54, 2 September 2008 (UTC)

Doesn't plain continuity also say that if the points are close then their images are close? — Carl (CBM · talk) 13:09, 2 September 2008 (UTC)

Of course :) Clearly this informal idea needs to be made precise, and depending which way you make it precise you get either continuity or uniform continuity. What I was trying to point out is that the non-standard definition captures the flavor of the "informal idea" better than the epsilon-delta quadruple quantifier. Katzmik (talk) 13:33, 2 September 2008 (UTC)

I think they're two rather different ways of looking at uniform continuity: the standard definition says that not only if points are close then their images are close, but that the degree of closeness you can expect doesn't depend on where you pick your points. The non-standard definition says that not only if points are close then their images are close, but that this holds for infinite or infinitesimal points. The standard definition is inherently global; the non-standard is 'local at infinity'. The standard definition corresponds more closely with my informal ideas of uniform continuity, but your intuitions may vary. Algebraist 14:20, 2 September 2008 (UTC)

One basic point here is that internally, there is no difference between finite points and infinite points, i.e. you cannot distinguish them internally. This is the same point as in the discussion of the proof of the IVT that was clarified by Arthur Rubin. Katzmik (talk) 14:32, 2 September 2008 (UTC)

Controversy over Cantor's theory

I'm going to work on editing Controversy over Cantor's theory. I'm torn about whether it should just be merged into Cantor's theorem. If you have an opinion, please let me know. — Carl (CBM · talk) 12:42, 4 September 2008 (UTC)

If I may be allowed to add my penny's worth, they should not be merged, as one is an article in the history of math while the other, in math itself. Furthermore, Bishop_''vs''_Keisler could reasonably be included at the controversy but not at the theorem :) Katzmik (talk) 12:46, 4 September 2008 (UTC)

I'm glad to hear opinions. The main justification for a merge is the general practice of avoiding "controversy" articles, since they invariably attract crank posts and degrade in quality. I wonder if the article could be renamed to "Objections to set theory" or something like that. In any case, the article as it stands has quite a bit of information very little structure. — Carl (CBM · talk) 13:03, 4 September 2008 (UTC)

That's interesting. I am not (yet) familiar with the crank post phenomenon. I suppose I will soon find out at Bishop-Keisler controversy :) Can you give me an example of this sort of thing? Katzmik (talk) 13:09, 4 September 2008 (UTC)

The "Controversy" issue comes up more often with political controversies. What often happens is that, when someone feels that an article doesn't focus enough on an recent incident that they think is important, they make a new article dedicated to focusing on that one issue with no regard to its overall importance. This is described somewhat at Wikipedia:Content forking.

For an example of a single-issue account in mathematics, see Special:Contributions/Manifesto50. That added content isn't so bad, in the end, and nobody has gotten around to trying to improve it. But it's clearly just this person's opinion that he/she wanted to see added to the encyclopedia. With forked articles there are fewer other editors watching to detect if an addition is in need of urgent help.

The article on Goedel's incompleteness theorem also tends to attract a decent number of crank posts, especially on the talk page.

I'd recommend looking through Talk:Controversy_over_Cantor's_theory/Archive1 to get a sense of the origins of that article. — Carl (CBM · talk) 13:24, 4 September 2008 (UTC)

To CBM: I agree with Katzmik that the two articles should be separate. Cantor's theorem should link to Controversy over Cantor's theory and vice versa, but they already do so. JRSpriggs (talk) 07:17, 5 September 2008 (UTC)

spin stabilization

hey, thanks for the fast footwork on making spin stabilization a redirect to Spin-stabilized satellite... but I really don't think that's the best plan of attack. Spin stabilization is a process that is not limited to satellites; it needs its own article. Ling.Nut ^(WP:3IAR) 08:38, 5 September 2008 (UTC)

epsilon numbers

I agree that there is little need for separate articles for ε₀ and "epsilon numbers" generally. I thought some of Mr Death's content was enlightening, so I merged it into the ε₀ article, along with some more exposition about the connections between Knuth's up-arrow notation and the "epsilon map", and between Conway's surreal epsilon numbers and fixed points of the exponential map generally. I did those bits from memory, and will turn up a proper reference for them ASAP. OK? Michael K. Edwards (talk) 23:12, 11 September 2008 (UTC)

Gravity drag

Can you perhaps clarify the meaning and relevance of the equation that you added to the gravity drag article ? See my post at Talk:Gravity drag for more details. Gandalf61 (talk) 09:49, 12 September 2008 (UTC)

Relativistic Force Reverted

Why did you revert the section I wrote on the derivation of the relativistic force? The formula that you reverted to isn't even correct. DS1000 (talk) 23:40, 18 September 2008 (UTC)

infraneologism

Hi, Probably you should save your energy and avoid further edits of inframetric as it is likely to be deleted as a neologism. Katzmik (talk) 08:18, 19 September 2008 (UTC)

Using the metric

Please explain why

$\eta ^{\mu \alpha }\eta ^{\nu \beta }F_{\alpha \beta }=F^{\mu \nu }.\,$

is not true. --Michael C. Price ^talk 06:39, 23 September 2008 (UTC)

The main point of my reversion was that permittivity and magnetic permeability are not always related by

$\varepsilon \mu ={\frac {1}{c^{2}}}$

which is what your edits were assuming. Furthermore, the very concepts of permittivity and magnetic permeability do not always apply to material media. Sometimes one must use non-linear expressions for the electric polarization and magnetization instead.

I agree with you that it is standard (and OK) to define

$F^{\mu \nu }=\eta ^{\mu \alpha }\eta ^{\nu \beta }F_{\alpha \beta }.\,$

However, it is not reasonable to assume that the audience of the article special relativity is familiar with that definition. Thus we should not use it (without giving the definition first). JRSpriggs (talk) 06:27, 24 September 2008 (UTC)

The metric is defined and linked earlier in the article. --Michael C. Price ^talk 21:54, 24 September 2008 (UTC)

Brent's method

Hi JRSpriggs,

I just posted a question on that article's talk page, your kind help would be greatly appreciated.

Thanks, laug (talk) 11:58, 25 September 2008 (UTC)

Wikipedia's Expert Peer Review process (or lack of such) for Science related articles

Hi - I posted the section with the same name on my talk page. Could you take part in discussion ? Thanks ARP Apovolot (talk) 00:12, 26 October 2008 (UTC)

Why have you accussed me of vanalism ?

Why have you accussed me of vanalism ? You have reverted my edit with no explanation. What are you doing ? Delaszk (talk) 18:02, 30 October 2008 (UTC)

Warning

Please do not attack other editors. If you continue, you will be blocked from editing Wikipedia. re comments made at Wikipedia talk:WikiProject Physics#De Sitter relativity at AfD; do not promote your opinions of other editors and do not edit war to return them. LessHeard vanU (talk) 13:39, 28 November 2008 (UTC)

It was not my intention to make the other user feel bad. I was trying to draw attention to an ongoing situation which is causing problems in several articles about relativity. I am sorry that my method went beyond the boundaries. JRSpriggs (talk) 05:02, 29 November 2008 (UTC)

References added, please don't delete again

Hi, I added references that prove that the relativistic formulation is correct< ref>http://academic.reed.edu/physics/courses/Physics411/html/411/page2/files/Lecture.10.pdf</ref>. Please don't delete again. DS1000 (talk) 00:40, 17 December 2008 (UTC)

I regret to inform you that the material you added is still wrong. See the talk page Talk:Hamiltonian mechanics#DS1000's added material. JRSpriggs (talk) 05:19, 18 December 2008 (UTC)

I think that this is repeat of the "Relativistic Force" entry, where you edited things out because you didn't understand them. I asked you not to delete without talking, is this too difficult to understand? I separated the relativistic Hamiltonian from the classical one, I hope that this will put an end to this. DS1000 (talk) 05:38, 18 December 2008 (UTC)

Good collaboration on Relativistic charged particle in an electromagnetic field

This collaboration worked out well between the two of us. We need to try working the same way next time DS1000 (talk) 06:17, 20 December 2008 (UTC)

Re: NOR

I'm sorry, JR, that I had not yet activated my user page. It is now active. Meanwhile, my question for you is - Specifically what in my editing addition(special relativity page) constituted, in your opinion, a NOR issue. Thankyou, Ray. —Preceding unsigned comment added by Rayclipper (talk • contribs) 01:49, 2 January 2009 (UTC)

Re: NOR (2)

Sorry. Let me try again, this time remembering to sign, so that it will hopefully be editable: What specifically, in your opinion, constituted a NOR issue with my special relativity addition pertaining to an absolute frame of reference? Thankyou, Ray. Rayclipper (talk) 02:01, 2 January 2009 (UTC)

g-force

I noticed you were on the relativity task force, and you'd edited recently.

There's a discussion over at Talk:g-force about whether g-force is a measure of acceleration. Could you cruise over if you have a chance and give your opinion? Many thanks- (User) Wolfkeeper (Talk) 23:33, 19 January 2009 (UTC)

Epsilon tensor

I've added a proof to the talk page of why there should be a minus sign to the talk page. If you still disagree, please first find the fault in the proof. Tomhosking (talk) 17:52, 27 January 2009 (UTC)

Action

I'm sorry to revert without discussion, but I wanted to get in before any further edits made recovery difficult.

The principal reason for my prompt revert is that your "correction" applies only to the quantum mechanical interpretation of action. Since the rest of the article is devoted almost entirely to the action in classical mechanics, this was likely to be confusing, especially to the les well-informed reader (who should, after all, be the primary target audience for the article intro). It is notable that the term "wave function" that you introduced in your "correction" is not mentioned anywhere else in the article - which will surely confuse the keen teenage would-be physicist at whom I aim my contributions.

It is possible that you are one of the specialists (I meet a lot of them), who believe that classical mechanics died with the discovery of quantum mechanics — believe me, it did not! For any macroscopic system under normal thermodynamic conditions (that is, wherever the Ehrenfest theorem applies), classical mechanics is the only practical tool for analysis. I would guess that for every physicist applying quantum analysis to a problem, there are at least a hundred engineers applying classical mechanics! ... and of course, that means that there are still loads of people being taught classical mechanics, who may seek help and inspiration from Wikipedia. It is also the case that almost everyone who studies mechanics will encounter the classical action before they are introduced to its quantum interpretations, so the classical action should at least appear first in the article.

With regard to my intro, there ARE some "deficiencies" of which I am well aware:

• "energy distribution" is an ambiguous term, and would indeed be likely to be misunderstood (as, for example, a Boltzmann distribution) by an informed reader if used in isolation. I used this term to capture the essential physical content of the Lagrangian (that is, the distribution of energy between kinetic and potential) for less informed readers who had not (yet, or perhaps ever) been formally taught about the (classical) Lagrangian. The link to the Lagrangian article was available for anyone who wanted to understand more.
• "state L(t)" of course the Lagrangian is a function of the state (not a state); I could have explained this (perhaps introducing some general state vector as an explicit argument of the function), but I felt this would break the flow of the introduction, and make it less readable by the less well-informed. This simplification is fully elaborated later in the article, for anyone with the education and perseverance to read on that far.

Please think carefully about my intentions before "correcting" these "deficiencies".

On a more positive note - I do agree that the article lacks any coherent presentation of the development of the action concept in quantum mechanics, and so is seriously distorted. If you could put together a section in the main body of the article summarising this area, I'm sure it would enhance the value of the article. FredV (talk) 01:02, 12 February 2009 (UTC)

See Action (physics) and Talk:Action (physics). JRSpriggs (talk) 05:29, 13 February 2009 (UTC)

AFDNote|Peter Lu

An article you had created Peter Lu has been nominated for deletion. Shawn in Montreal (talk) 04:30, 26 February 2009 (UTC)

Good one!

Excellent amendment! Cheers, DVdm (talk) 18:36, 2 April 2009 (UTC)

Thank you. I am glad that you appreciate it. JRSpriggs (talk) 20:38, 2 April 2009 (UTC)

Natural number

Dear JRSpriggs: Could you please provide your reasons for undoing my recent edit to Natural number? I gave my reasons for the edit in the edit summary, but you did not give any reason for undoing it, so I do not know what you are thinking. I might add that my edit, in addition to eliminating redundancy, goes along with a suggestion in the Wikipedia Manual of Style for mathematics articles: "A general approach is to start simple, then move toward more abstract and technical statements as the article proceeds." Looking forward to your reply, FactSpewer (talk) 02:49, 13 April 2009 (UTC)

Since "countably infinite" and "aleph-null" are defined in terms of the set of natural numbers, it seems appropriate to me to mention that fact in the section dealing with notations for the natural numbers and related things.

A little redundancy helps communication.

The section on generalization seems too far down in the article to introduce these ideas. JRSpriggs (talk) 05:02, 13 April 2009 (UTC)

Thank you for the explanation. I still find my reasons more compelling, so I guess I'll ask at the Natural number Talk page to see what other people think. FactSpewer (talk) 03:15, 15 April 2009 (UTC) P.S. For the future, you may wish to read Help:Reverting#Explain reverts.