Revision as of 11:13, 12 September 2009 editMichael C Price (talk | contribs)Extended confirmed users19,197 edits →Comment on Physchim62's allegations← Previous edit | Revision as of 11:23, 12 September 2009 edit undoFDT (talk | contribs)7,708 edits Michael Price's statement here is the very epitome of what needs to be investigated in this disputeNext edit → | ||
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Here again we see Michael Price and Physchim62 attempting to misrepresent the argument and invoking sensational terms such as 'pseudoscience'. The facts are that the ] in SI units is a defined quantity that is beyond measurement, whereas the physical speed of light is a measured quantity. Hence we have two different concepts. If the best argument that Michael Price can come up with is to state that his opponents are wrong, then he doesn't have much of an argument. As regards the point made by Physchim62, the c in the equation ''E'' = ''mc''<sup>2</sup> follows from the measured value of E/m. Based on Maxwell's equation (132) in his 1861 paper, this is the electromagnetic/electrostatic ratio as determined experimentally using a discharging capacitor. Maxwell uses the density and the transverse elasticity of the medium that light is propagating in. Hence E/m is equivalent to 1/(εμ), where μ is the density and where ε is related to the inverse of the transverse elasticity. In other words, E refers to the energy in the medium. In 1908, ] derived ''E'' = ''mc''<sup>2</sup> from Maxwell's radiation pressure equation, although I've read that he probably derived it as early as 1903. From all of this, it is clear that we cannot use the SI defined ] in the equation ''E'' = ''mc''<sup>2</sup>. ] (]) 10:50, 12 September 2009 (UTC) | Here again we see Michael Price and Physchim62 attempting to misrepresent the argument and invoking sensational terms such as 'pseudoscience'. The facts are that the ] in SI units is a defined quantity that is beyond measurement, whereas the physical speed of light is a measured quantity. Hence we have two different concepts. If the best argument that Michael Price can come up with is to state that his opponents are wrong, then he doesn't have much of an argument. As regards the point made by Physchim62, the c in the equation ''E'' = ''mc''<sup>2</sup> follows from the measured value of E/m. Based on Maxwell's equation (132) in his 1861 paper, this is the electromagnetic/electrostatic ratio as determined experimentally using a discharging capacitor. Maxwell uses the density and the transverse elasticity of the medium that light is propagating in. Hence E/m is equivalent to 1/(εμ), where μ is the density and where ε is related to the inverse of the transverse elasticity. In other words, E refers to the energy in the medium. In 1908, ] derived ''E'' = ''mc''<sup>2</sup> from Maxwell's radiation pressure equation, although I've read that he probably derived it as early as 1903. From all of this, it is clear that we cannot use the SI defined ] in the equation ''E'' = ''mc''<sup>2</sup>. ] (]) 10:50, 12 September 2009 (UTC) | ||
:The argument is simple and has been given many times before. "''the ] in SI units is a defined quantity that is beyond measurement, whereas the physical speed of light is a measured quantity. Hence we have two different concepts.''" They are not different concepts; by measuring the speed of light you are, by definition, measuring the metre. It doesn't matter how many times you state they are different, they are the same ''by definition''. --] <sup>]</sup> 11:13, 12 September 2009 (UTC) | :The argument is simple and has been given many times before. "''the ] in SI units is a defined quantity that is beyond measurement, whereas the physical speed of light is a measured quantity. Hence we have two different concepts.''" They are not different concepts; by measuring the speed of light you are, by definition, measuring the metre. It doesn't matter how many times you state they are different, they are the same ''by definition''. --] <sup>]</sup> 11:13, 12 September 2009 (UTC) | ||
::Michael, If I measure the ], I measure the ]. If in this new system you claim that I am measuring the metre, then we are talking about two completely different concepts. No definition can make a measured quantity the same thing as a defined quantity. I hope that the arbitrators examine your statement above very very carefully because this is the very kind of thing that I have been strongly objecting to. Your statement above, and the fact that you believe in it is the very epitome of what needs to be investigated here. This statement constitutes pure confusion. It is the kind of deliberate confusion that has been used on an ongoing basis to spam out rational argument in relation to this controversy. It is on Michael Price's statement above that I rest my case, and I will engage no further in this matter here. I will leave it for the arbitrators to decide. ] (]) 11:23, 12 September 2009 (UTC) | |||
==Comment on Totientdragooned's proposals at the workshop== | ==Comment on Totientdragooned's proposals at the workshop== |
Revision as of 11:23, 12 September 2009
Comment on evidence presented by Tim Shuba
I am not a physicist so feel free to discount what I say accordingly. I have not edited any of the articles in question. However, I have had a few opportunities in the past to engage in conversation on-Wiki with Tim Shuba, and I can report that in my opinion he is a cautious, circumspect and helpful editor, who shows no trace of arrogance or condescension to lay people and is pleased to volunteer helpful information. Arbitrators may want to take my comments into account as they consider criticism launched at Shuba by Tombe and Brews. --Goodmorningworld (talk) 17:49, 9 September 2009 (UTC)
- The following also might be taken into account as indicative of a grave acceptance of responsibility:
Brews ohare (talk) 00:20, 10 September 2009 (UTC)“Primarily, I use wikipedia for enjoyment rather than attempt to edit seriously. Since I am aware of how and why so much blatantly bogus information gets into articles, and why a large number of articles are highly unreliable, it doesn't affect me adversely as a user. Therefore, whether the speed of light article gets better or gets worse isn't too important to me.″ Tim Shuba
Goodmorningworld, You seem to be totally overlooking the fact that Tim Shuba is the one who launched the criticism at Myself and Brews. The only thing that I have written that might be interpreted as criticism of Tim Shuba was my reference to the fact that he deleted a large and very important sub-section from the history section of the speed of light article on 29th August, hence leaving an inexplicable gap in the chronology. I wasn't the one who actually put in that sub-section on the luminiferous aether, however, I made substantial modifications to the paragraph regarding Maxwell's role in that part of the history of the speed of light. I challenged Tim Shuba on his talk page as to why he had removed that sub-section, and he replied with double irony disguised as humour. It's all very nice that you can come here as a non-physicist and give a character reference for Tim Shuba, but eventually the merits of Tim Shuba's removal of that section will have to be judged by somebody with a knowledge about electromagnetism. David Tombe (talk) 08:46, 10 September 2009 (UTC)
What is really going on with David Tombe (moved from Evidence page)
In part of a longish rant to Jimbo Wales' talk page, Dave Tombe wrote, "I have therefore attempted to introduce specialized knowledge back into wikipedia in areas that I have done alot of research in."
As regarding physics articles, this statement refers to nineteenth century theories. In particular, the period of "the old real physics", before "the new nonsense physics" of Einstein's theory of relativity. Most of David Tombe's contributions to physics article have this extreme fringiest of the fringe motivation (since the word crank can be incivil, I will endeavor to use euphemisms, though I admit to having used it freely when I first commented about David Tombe). Here are some examples of the kind of "specialized knowledge" we can expect to be introduced.
- "It is likley that Einstein misunderstood Maxwell's equations."
- "Einstein on the other hand appears to have totally failed to grasp anything that Maxwell said at all."
Please arbitrators and other uninvolved interested parties, find an acquaintance who is conversant in physics and ask about these quotes. They are utterly preposterous, show no expertise whatsoever, and bode ill for anything but the attempted introduction of disruption and pseudoscience into the encyclopedia. Many of the recent arguments in the speed of light article center around this 1983 definition, and this undoubtedly leaves outsiders bemused. Well, the theoretical reasoning (there are other reasons) for this definition is solidly based on Einstein's theory of relativity. As such, it is antithetical to David Tombe's extreme minority point of view. In his words, "his most important chapter of scientific history has now degenerated into the abominable post-1983 new physics that is summed up in the lead to the vacuum permittivity article."
David Tombe's participation in physics articles is the epitome of what needs to be addressed within the context of the intent of the arbcom pseudoscience decision. Tim Shuba (talk) 04:18, 10 September 2009 (UTC)
Statement transferred from Evidence Page
Despite all that Tim Shuba has said above, I have not been putting original research into the articles. My major contribution to the speed of light article was in the history section. It passed the consensus and remained there for a few weeks until Tim Shuba deleted it. Here is the content material in question as removed by Tim Shuba. I wrote most of the middle paragraph beginning with Wilhelm Eduard Weber and Rudolf Kohlrausch in 1856, down to Maxwell's 1865 paper. With the exception of a few modifications relating to Maxwell's 1865 paper that were made by Martin Hogbin, that paragraph is essentially mine. So why did Tim Shuba remove it? That is perhaps the most crucial aspect in the entire history of the speed of light. It relates to how James Clerk-Maxwell showed the linkage between the measured speed of light and the electic and magnetic constants (nowadays referred to as the electric permittivity and the magnetic permeability). I have expanded on this issue in a series of articles that are published in an on-line journal entitled 'The General Science Journal'. There was actually a wikipedia article page about that journal until Tim Shuba had it deleted about a week ago.
Until last month, I knew absolutely nothing about the decision to re-define the metre in 1983 in terms of the speed of light. When I investigated the matter, I discovered that Brews was absolutely correct. The metre is now defined as the distance that light travels in a specified fraction of a second. That means that in SI units, the speed of light is then defined in terms of itself, and so it immediately loses the connection with the physical speed of light and becomes a mere definition with an arbitraily assigned number. It means that in SI units, the speed of light is beyond measurement and it is therefore important that the article introduction clearly makes a distinction between the new SI speed of light on the one hand, and the physical speed of light as is expressed in other systems of units and which can be measured. My involvement in the main article in relation to that issue was minimal and I was not involved in the edit war. Instead, I went to investigate the knock-on effect that this new definition would have on the electric permittivity, and how Maxwell's discovery in 1861 would be written up in the textbooks in the context of the new 1983 definition. The experiment in question was still in my 1979 edition of 'Nelkon & Parker'. I brought up the subject at WT:PHYS. An editor Headbomb tried to tell me that since 1983 we can no longer put a ruler across the plates of a capacitor and measure the distance. He told me that instead we will be in fact merely calibrating the ruler. I considered this to be total nonsense and I made my opinions about it clear on the speed of light talk page. An editor called Physchim62 then ran to AN/I to complain that I was engaging in disruptive editing, and I got promptly page banned without any apparent investigation into the truth of the allegation. Meanwhile, Christopher Thomas, who was the only one who seems to have understood my argument at WT:PHYS came along and maliciously presented the WT:PHYS thread as evidence of disruptive behaviour. Since then, I have been to the science library and confirmed my suspicions, that since 1983, the capacitor experiment that links the electric permittivity to the speed of light has disappeared from the textbooks. I did find one exception, and that was the 1995 (seventh edition) of 'Nelkon & Parker'. This then goes full circle to the bit in the history section that Tim Shuba deleted. The main question that needs to be asked at this hearing is, 'Why did Tim Shuba remove that edit? In doing so, he removed a vital chunk from the chronology in the history section. I questioned him about it on his talk page and all I got in return was double irony disguised as humour. And whatever the answer is, you'll find that it is the exact same reason why he and certain others don't want Brews to elaborate on the significance of the 1983 definition of the metre. That's why I've suggested that the article be handed over to Steve Byrnes and semi-protected for six months, with a voluntary withdrawal of all the disputing parties. David Tombe (talk) 08:07, 10 September 2009 (UTC)
Comment on Physchim62's allegations
Physchim62 has just made a statement on the evidence board to the extent that he believes that I believe that I own the speed of light article. He then asks whether or not he must present evidence that I don't believe it. The answer is that he doesn't have to. But he must present evidence that I do believe it, and so far, he has presented none. And he would have a very hard job presenting any such evidence in view of my minimal involvement in the article. Ultimately it was Physchim62 that started all this. He started it when he went to AN/I to report me for disruptive behaviour without presenting any evidence of what disruption was actually caused. It is because of that singular action on the part of Physchim62 that this whole arbitration hearing has come about. Therefore it might be a good idea if the hearing begins with Physchim62 presenting evidence of the actual disruption that was caused by my edits. If he can't present evidence of any actual disruption, then questions need to be asked by the higher authorities. David Tombe (talk) 13:45, 10 September 2009 (UTC)
- Several uninvolved administrators decided that your behaviour at Talk:Speed of light was sufficiently disruptive to merit a topic ban from such articles. If you continue such an editing style on these pages, it will hardly do much for your case. The single talk page section , quoted in my evidence section, shows your desire to have editing at Speed of light "handed over" (that was your term in the title of the talkpage section) because "verybody else tried to sweep that experiment under the carpet because it isn't compatible with the new unmeasurable speed of light"; that is, so that (you hope) your absolutely fringe view of physics will continue to be promoted on Misplaced Pages. I think that justifies any accusations against WP:OWN although it is not, of course, my decision to make at this venue. Physchim62 (talk) 14:10, 10 September 2009 (UTC)
Physchim62, An experiment in physics disappeared from the textbooks because of a new system of units. There are plenty of sources on the library shelves to prove that. Practically any modern physics textbook proves it. Do you want to subordinate real physics to a system of units? Bringing that issue to attention at WT:PHYS is not disruptive behaviour, and the term 'fringe physics' has got nothing to do with it. You need to learn to start actually debating these issues rather than running off to noticeboards trying to get your opponents disqualified. The issue here is, "do we report the physical speed of light and the defined speed of light as two distinct topics, or do we only report the defined speed of light and sweep the physical speed of light under the carpet? Do we sacrifice the physical speed of light to the SI system?". David Tombe (talk) 14:28, 10 September 2009 (UTC)
- We do none of the above. We simply report that the speed of light is defined in terms of metres/second. Measuring the speed of light is the same as measuring the length of the metre. Only Brews and you have a problem with that. I don't have to measure the number of inches in a foot to know that it is 12 inches per foot. But that doesn't tell me how long an inch is. Only Brews and you can't see the analogy.--Michael C. Price 15:13, 11 September 2009 (UTC)
Michael, That of course is the big problem. You want to limit the article to reporting about a defined speed of light in metres/second that is beyond measurement. Brews on the other hand additionally wants to report about the physical speed of light as is expressed in other systems of units, and which can be measured. David Tombe (talk) 15:52, 11 September 2009 (UTC)
- David, Brews is mistaken, as are you. See below. Your objection to the speed of light being defined in metres/second is as fundamentally pointless as objecting to the foot being defined as 12 inches. --Michael C. Price 04:48, 12 September 2009 (UTC)
- Michael C. Price: Your remark: "Measuring the speed of light is the same as measuring the length of the metre." is untrue, at least if you stay within the SI units. In the SI units the "speed of light" is a defined numerical value of 299,792,458 m/s “a defined constant, not to be measured again″. The metre is defined as (BIPM SI Units brochure, § 2.1.1.1, p. 112) the distance light travels in 1/299,792,458 s, regardless of whatever the true value of the real speed of light might be, so ipso facto the SI units' "speed of light" is 299,792,458 m/s, period. Of course, one can go outside the SI units and measure the metre in (say) wavelengths, and then the actual speed of light can be measured in units of wavelengths per second. That measurement is entirely unrelated to the number 299,792,458 m/s. Perhaps that is what you mean, although I have no evidence that other editors on Speed of light such as Martin Hogbin, TimothyRias or Finell share that opinion. Brews ohare (talk) 18:25, 11 September 2009 (UTC)
- My statement as quoted is true, regardless of any qualification about SI, since the metre is defined via SI. None of your following statements change this. And this is understood by the other editors. As we saw when this was queried by you, no one dissented. --Michael C. Price 04:48, 12 September 2009 (UTC)
- "regardless of what the true value of the speed of light may be…" That is absolutely classic Brews. "The Truth Is Out There", "Trust No One", "I Want to Believe". The speed of light measured as the product of a wavelength and a frequency and the speed of light which is defined as 299,792,458 m/s are exactly the same physical constant. As far as we can tell, this is also the same physical constant which appears in E = mc and in the Lorentz transformations used in Special Relativity, although if someone were to show that the two are very slightly different then it would hardly be the end of modern physics. All the time that Brews and David cannot accept this, they will be spouting pseudoscience. Physchim62 (talk) 09:40, 12 September 2009 (UTC)
- My statement as quoted is true, regardless of any qualification about SI, since the metre is defined via SI. None of your following statements change this. And this is understood by the other editors. As we saw when this was queried by you, no one dissented. --Michael C. Price 04:48, 12 September 2009 (UTC)
Here again we see Michael Price and Physchim62 attempting to misrepresent the argument and invoking sensational terms such as 'pseudoscience'. The facts are that the speed of light in SI units is a defined quantity that is beyond measurement, whereas the physical speed of light is a measured quantity. Hence we have two different concepts. If the best argument that Michael Price can come up with is to state that his opponents are wrong, then he doesn't have much of an argument. As regards the point made by Physchim62, the c in the equation E = mc follows from the measured value of E/m. Based on Maxwell's equation (132) in his 1861 paper, this is the electromagnetic/electrostatic ratio as determined experimentally using a discharging capacitor. Maxwell uses the density and the transverse elasticity of the medium that light is propagating in. Hence E/m is equivalent to 1/(εμ), where μ is the density and where ε is related to the inverse of the transverse elasticity. In other words, E refers to the energy in the medium. In 1908, Gilbert N. Lewis derived E = mc from Maxwell's radiation pressure equation, although I've read that he probably derived it as early as 1903. From all of this, it is clear that we cannot use the SI defined speed of light in the equation E = mc. David Tombe (talk) 10:50, 12 September 2009 (UTC)
- The argument is simple and has been given many times before. "the speed of light in SI units is a defined quantity that is beyond measurement, whereas the physical speed of light is a measured quantity. Hence we have two different concepts." They are not different concepts; by measuring the speed of light you are, by definition, measuring the metre. It doesn't matter how many times you state they are different, they are the same by definition. --Michael C. Price 11:13, 12 September 2009 (UTC)
- Michael, If I measure the speed of light, I measure the speed of light. If in this new system you claim that I am measuring the metre, then we are talking about two completely different concepts. No definition can make a measured quantity the same thing as a defined quantity. I hope that the arbitrators examine your statement above very very carefully because this is the very kind of thing that I have been strongly objecting to. Your statement above, and the fact that you believe in it is the very epitome of what needs to be investigated here. This statement constitutes pure confusion. It is the kind of deliberate confusion that has been used on an ongoing basis to spam out rational argument in relation to this controversy. It is on Michael Price's statement above that I rest my case, and I will engage no further in this matter here. I will leave it for the arbitrators to decide. David Tombe (talk) 11:23, 12 September 2009 (UTC)
Comment on Totientdragooned's proposals at the workshop
Totientdragoon has made a series of noble proposals at the workshop. But until he can show where these issues have been breached up until now, it's hardly going to get to the root of the problem. The problem at speed of light has got absolutely nothing to do with original research, righting wrongs, soapboxing, disruptive behaviour, or fringe views. The problem at speed of light is about what balance to apply regarding two different concepts of the speed of light as in (1) the defined speed of light in SI units that is beyond measurement, and (2) the physical speed of light as is measured in most other systems of units.
It follows therefore that Totientdragooned's proposals are tantamount to pre-empting the judgement. The proposals assume that some of the involved editors have been guilty of breaching these issues. Until it can be proved that some of the editors have been guilty of disruptive behaviour, or soapboxing, or whatever, then these proposals are totally irrelevant as far as solving the problem is concerned, and they should be shelved until the judgement is completed. In fact, Totiendragoond's proposals are merely a re-statement of the existing wikipedia rules. David Tombe (talk) 08:01, 11 September 2009 (UTC)
- Yes, that is correct. They are proposed principles, not evidence or findings of fact about any particular party.TotientDragooned (talk) 14:59, 11 September 2009 (UTC)
OK. But they are already part of wikipedia's rules and regulations. We need to be aware of the fact that one side in particular in this dispute is making unsubstantiated allegations about behaviour. I am not interested in sanctions being imposed against anybody. However, when all of this is over, I would hope that warnings are given to all parties who have made unsubstantiated allegations, because it is those unsubstantiated allegations that have been the only thing so far that have disrupted the debate on the speed of light talk page. David Tombe (talk) 16:00, 11 September 2009 (UTC)
Comment on Steve Byrnes's evidence
Once again we see a series of allegations relating to my off-wiki activities. But not a single shred of evidence has been presented as regards inserting original research into main articles. I began my dealings with Steve Byrnes before I started using my proper username. The issue in question was Faraday's law. Steve Byrnes believed that he had detected two Faraday's laws in electromagnetism, and he wanted to amend the Faraday's law article to that end. I tried and succeeded in holding him back from doing so, while explaining to him that in fact there is only one Faraday's law, but that it contains two aspects, and that only one of those aspects is catered for in the modern version of Maxwell's equations, which is why we have to supplement those equations with the Lorentz force. Steve finally realized the inter-relationships after I had demonstrated them to him. There was somewhat of a hitch over the issue of the fact that I was using Maxwell's original papers, and that Maxwell's idea of 'electromotive force' does not correspond exactly with the modern notion of the concept. I was using the term E for F/q in the equation F = qvXB. Hence I was writing E = vXB which is a format that is not used nowadays. But that is the format that is needed in order to show the inter-relationship between the two aspects of Faraday's law. I then had a debate with Steve about the Biot-Savart law and how to reconcile its singularities with its solenoidalness. That steered me into having to divulge the fact that I believe that the Biot-Savart law, just like the centrifugal force, has to obey the inverse cube law, and not the inverse square law as is commonly believed. But I never wrote that in the main article. Others have tried to do that, but I never have.
In my dealings with Steve, I found him to be very knowledgeable in physics, and competent in mathematics, but there were certain patterns which he clearly hadn't seen until I drew his attention to them. In a few other exchanges he has proved to have taken a very balanced approach, which is why I recommended him to be a neutral arbitrator in this dispute. I'm sorry that he has refused the olive branch, and I'm sorry that he has now misrepresented my position in this current speed of light dispute. I didn't say that the BIPM definition was impossible. It is quite possible, but I do believe that it was a mistake. Having said that, I have never once attempted to write my opinions on that matter into the main article. I have attempted to explain on the talk page why the BIPM definition of the metre means that the ensuing speed of light is a definition that is beyond measurement, and hence why it is a different concept than the physical speed of light, that can be measured. I entered the dispute on the talk page to help out Brews who was being rounded on by a crowd, who in my opinion were wrong, and who were trying to hush up this important 'sourced' fact.
I have already suggested that Steve Byrnes should now be allowed a free hand to write the article himself, which should then be semi-protected for six months. I still think that that would be a good idea. Steve has made it clear that he is no ally of mine, and so that should dispel any doubts that he would be biased towards my point of view on the matter. He knows his stuff. Somebody has to write the article coherently. At the moment it is just a pie throwing contest and something needs to be done. I know that Steve will write the article in a balanced fashion, irrespective of his prejudices towards me. If you ban me, as Steve has proposed, it's hardly going to make much difference. I haven't edited the main aticle since 12th August and I have made minimal edits to the talk page in recent weeks. I am not the source of the trouble at that article, and I don't believe that Brews is either. The source of the ongoing trouble at the speed of light article is the confusion that has been sewn by the 1983 BIPM definition.
So I say to Steve, put your bitterness about the Faraday's law argument behind you and move forward. David Tombe (talk) 13:29, 11 September 2009 (UTC)
Comment on Martin Hogbin's evidence
Martin Hogbin has now decided to parrot what Tim Shuba and Steve Byrnes have said. My dealings with Martin Hogbin relate to the history section in the speed of light aticle. Martin, attempted to do exactly what Tim Shuba did after I had been banned. Martin tried to remove all mention of Maxwell's 1861 paper in relation to how Maxwell linked the speed of light to the electric and magnetic constants. Ironically, Martin was happy enough to reinsert this material, but in relation to Maxwell's later approach in his 1865 paper. The difference with the 1865 paper that made it more acceptable to Martin was the fact that it didn't involve any explicit references to Maxwell's sea of molecular vortices. In the end, both the 1861 paper and the 1865 paper were treated in the history section, even though I was of the opinion that the latter was superfluous to requirements. At any rate, both of them dealt equally with the importance of Weber and Kohlrausch's experimental result that linked the electric and magnetic constants to the measured speed of light.
When Martin first removed the material about Maxwell's 1861 paper, he wrote in the caption "Remove Crackpot Physics". Martin has no qualms about referring to his opponents as crackpots even when that opponent is James Clerk-Maxwell. Once again today, he is referring to crackpot physics that I have been inserting into wikipedia. Can we all please see some examples of this crackpot physics. I suggest that the arbitrators cross-examine Martin Hogbin on two issues. (1) Why did Martin Hogbin remove the material on Maxwell's 1861 paper from the history section? and (2) Why does Martin Hogbin think that the physical speed of light should be ignored in the article to the exclusion of the defined speed of light as per the 1983 BIPM metre? Martin argues that the SI system is the official system and that as such only the SI speed of light should be mentioned. The SI system may well be the official system of units, but we cannot sacrifice the physical speed of light for a system of units. If we ever have to measure the actual speed of light, we have to use another system of units, and that needs to be made clear in the article. David Tombe (talk) 13:54, 11 September 2009 (UTC)