Talk:Kelvin/Archive 2

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Archive 1 Archive 2

Temperature problem

The article states that the triple point of water is precisely 0.01 degrees centigrade, but the article on triple point, states that more accuately the triple point of water is 0.0098 cegrees centigrade.

I do not know which is correct, although one might assume the 'more accurate' figure would be correct.

Can someone with knowlege edit this please?

Philip.t.day (talk) 17:49, 23 March 2008 (UTC)


There is an additional mistake at the "Kelvin temperature conversion formulae" on the right hand side: There it is written that 1 K = 1 C = ... it should be 274,15 K = 1 C = ... or 1 K = - 272,15 C but than F and all the other after it need to be changed too. — Preceding unsigned comment added by 87.77.204.237 (talk) 14:27, 8 January 2013 (UTC)

No! You need to read it again. That part says specifically: "For temperature intervals rather than specific temperatures, ..." - David Biddulph (talk) 14:59, 8 January 2013 (UTC)

Inconsistency in this article and many linked to it

Is the plural form of the kelvin "kelvin" or "kelvins"?

"Ten million kelvin" OR "Ten million kelvins"

67.171.43.170 03:40, 19 January 2007 (UTC)

Kelvin. Are we the only ones here? (-: 207.63.251.215 19:01, 5 February 2007 (UTC)
Kelvins. The belief that it should be 'kelvin' dates from before 1968 when the SI system used the 'Kelvin scale'. There were then 'degrees Kelvin', just as there are still 'degrees Celsius'. People used to abbreviate 'n degrees Kelvin' to 'n Kelvin', just as they still do with the Celsius scale.
The SI abolished the 'Kelvin scale' in 1967/68, and now states that the kelvin is just another unit. Therefore we now have 'n kelvins' just as we have 'n metres' and 'n seconds'. The SI brochure itself uses the term '273.16 kelvins' [1], and just in case you think this is a US/EU thing, here's the NIST saying the same thing: [2] --Heron 22:01, 6 February 2007 (UTC)
Even if plausible examples of the use of "kelvins" can be found, it has in my view not been generally adopted. One reason for this might be that we do not talk about "fahrenheits" and "celsiuses" and never have. — Preceding unsigned comment added by Loris Bennett (talkcontribs) 16:10, 8 December 2015 (UTC)
This can be found explained in many books. In fact, some scientific books go into some length on this matter (just check google books). When referring to the scale, it's "Kelvin." When referring to the unit of temperature, it's "kelvins." When referring to the color temperature of a light, it's "kelvin." Scientifically, this helps avoid confusion between the meanings, but, in general use, either or all three can be found. Like most of the English language, there are no standardized rules for pluralizing units of measurement. Society in general just makes this stuff up as they go along, and all we can do is follow the language as it changes. Zaereth (talk) 23:50, 15 December 2015 (UTC)

It makes no sense to use capital letters in many instances of the entry, then claim lowercase is the SI standard when spelled out. Besides which, you claim a capital "K" when abbreviated is preferred. A person's name is ALWAYS capitalized. The River Kelvin is named for a person, and the Baron Kelvin was titled for it. If I get a majority of people to claim SI is no longer SI, but si, does that make it right? Tradition has its place, and if William Thomson would not recognize what you have done to his work, no majority can make it right. —The preceding unsigned comment was added by 70.230.157.167 (talkcontribs).

See ohm, joule, coulomb, watt, and the other SI derived units. - mako 12:37, 19 February 2007 (UTC)

Colour vs. Color, and related spelling issues

The issue of British English vs. American English has been a subject of heated debate. Wikipedia’s current policy seems to be the most equitable, encourages contributions, and settles conflict. Per Wikipedia: Manual of Style: Disputes over style issues, the term originally used in the article by the first major contributor(s) should be retained. Greg L (my talk) 01:50, 1 April 2007 (UTC)

Deleting the existence of the “Kelvin scale”

Someone made this giganzo series of edits on the novel and most original notion that Resolution 4 of the 13th CGPM in 1967/68, which better defined the unit increment of thermodynamic temperature (as distinct from the scale), somehow “abolished” the “Kelvin scale” out of existence. You know, the “scale;” that “thing” created in 1954 by Resolution 3 of the 10th CGPM wherein absolute zero equals zero kelvin and the triple point of water equals 273.16 K. Perhaps the proponent of this theory should point this out to Encyclopedia Britannica since those poor fools believe the Kelvin scale still exists! (and repeated their error in this article too). Encyclopedia Britannica even took the effort to capitalize the word “Kelvin” when referring to this imaginary scale.

OK, I’m done being facetious. I’ve gone out on a limb here and restored the article with the reality that the word “kelvin” refers to both the unit increment and the scale upon which kelvin temperatures are based. This contributor’s wild notion isn’t supported by any number of Web sites like this site by the National Center for Atmospheric Research, or this NIST site, and this NIST site too, or this NASA site. Note that all these sites also took care to ensure that “Kelvin scale” is capitalized.

And to any contributor desiring to erase the Kelvin scale from existence, please cite an authoritative source to buttress your claim rather than simply flat declaring the scale no longer exists. Merely citing Resolution 4 of the 13th CGPM doesn’t cut it. Resolution 4 doesn’t say anywhere that the temperature scale is abolished, only that the unit increment is better defined. Oh, one other thing: please resist the temptation to declare that Encyclopedia Britannica and others like the NIST are wrong. You know, Encyclopedia Britannica actually hires and pays experts to write their articles. They also use professional (paid) editors to edit articles to make them flow well and to make them harmonious with articles on related topics. Though expensive, this way of making an encyclopedia does have its advantages.

Now, if you still can’t reconcile how the unit increment can peacefully coexist with the scale, just remember that the unit increment known as the kelvin is defined as 1/273.16th the difference between absolute zero and the triple point of water. It is a distinct noun; a thing, like the kilogram or meter. The combined intended effect of the 13th CGPM’s two back-to-back resolutions (Resolution 3 and Resolution 4), was there was now a clear, consistent, rational basis established for why one could measure both temperatures and intervals (like a 30 K temperature rise on a heatsink), without using a degree symbol (°) in front of the “K” symbol. However, the Kelvin scale still exists and its 1954 definition still holds whereby absolute zero is 0 K and the triple point of water is 273.16 K.

If you still feel that something in Resolution 4 of the 13th CGPM somehow abrogated the definition of the thermodynamic temperature scale, examine the wording at the beginning of the resolution:


And what does does Resolution 3 of the 10th CGPM say? It starts out with the following:


As you can see, far from abrogating Resolution 3 of the 10th CGPM, the 13th CGPM in 1967/68 was abundantly clear that they were keeping the thermodynamic temperature scale and were only “more explicitly” defining the unit comprising that scale. This is all sort of a Well… DUHHH  thing. After all, without the scale, we couldn’t measure temperatures; we could only measure temperature intervals. Note too that the CGPM never named the thermodynamic temperature scale, not even back in 1954; they referred to it by description: “the thermodynamic temperature scale.” Why? you might ask. Going back even further, to Resolution 7 of the 9th CGPM (1948), the formal name of the unit increment of temperature on the “thermodynamic temperature scale” was also somewhat descriptive rather than a good, proper name: “degree absolute” (symbol °K). So it was obvious to everyone and Koko the gorilla what the scale’s name became when the unit increment got its new name in 1967/68. It was, of course, even more obvious that nothing the 13th CGPM did erased the scale from existence.

And last: while the edits in question certainly met Wikipedia’s advise to contributors to “be bold” when making edits, a quick sanity check would have been helpful before deciding that the Kelvin scale “no longer exists.” Remember, Resolution 4 of the 13th CGPM (the one creating the unit increment called the kelvin) dates back to 1967/68. This event preceded the World Wide Web by over 22 years. One should have asked: “Why then, are there so many Web sites that mention the existence of the Kelvin scale?” It’s not like the term could be some sort of legacy holdover from bygone days. Greg L (my talk) 03:18, 1 April 2007 (UTC)

I seem to remember that I reworded the article to get rid of the clumsy first sentence - "Kelvin is, or relates to, a unit increment of temperature known as the kelvin (symbol: K)" - and various other minor style problems. My objection to that sentence is that its subject is the word "kelvin", not the kelvin or the Kelvin scale. Wikipedia articles are about things, not words, so this sentence needs to change.
I do admit, however, that the statement I made in my edit summary that "there is no longer a Kelvin scale" was wrong, although it was based on my Google search of the BIPM's website which revealed eight instances of "thermodynamic temperature scale" and none of either "Kelvin scale" or "Kelvin temperature scale". That was my sanity check. I know that the phrase "Kelvin scale" is widely used, even in the hallowed and infallible EB, but I thought it might have been superseded by the BIPM's usage. --Heron 19:43, 2 April 2007 (UTC)
Where do you get off declaring that “This article is about the kelvin [the unit]“? Is there a separate Wikipedia article for the Kelvin scale? No, there isn’t. This one article must properly address both nouns. The Kelvin scale” is a noun. So too is “the kelvin” (the unit increment). The word "kelvin” is part of either noun. Unless there are to be two entirely different Wikipedia articles, one titled “Kelvin (unit)” and another titled “Kelvin scale” (a highly inadvisable approach), it is important for readers to know that the word kelvin refers to two “things.” Further, this introductory format has been used successfully on the Celsius article for a long time with great success. A good indicator of the proper way to tackle this is how Encyclopedia Britannica handled it. They wrote in the introductory paragraph that the word applies to two different things. Any good encyclopedia would use this approach. What are you going to do, create a separate article for the Kelvin scale just to get your way? Give it up. Your logic makes no sense and is unsupportable. Greg L (my talk) 23:56, 2 April 2007 (UTC)
Update: After sleeping on it, I understood better what your objection is over how the “subject is the word ‘kelvin’”. I agree that the wording was rather dictionary-like than encyclopedia-like in nature. I hope you approve of the new wording. By making the first word in the sentence “The”, the following word “kelvin”, is lowercase (which is good when one is discussing the unit increment). As now revised, it deletes the “is, or relates to,” (which I suspect goes to the heart of what you felt was “clumsy”). And the new wording retains the important virtue of not deleting the Kelvin scale from existence; it addresses both nouns: the unit increment, and the scale. Peace? Greg L (my talk) 21:47, 3 April 2007 (UTC)
Yes, peace, Greg. I can find nothing to object to, factually, in the current wording, although having two successive sentences starting with 'The kelvin is...' is not ideal. Anyway, I'm not going to change them in case this starts to look like a tit-for-tat exercise. I'll let someone else take care of that. Thank you for accommodating my views, which is generous of you given my misinterpretation of Resolution 3/13th. I guess I must have seen the abolition of the term 'degree Kelvin' and jumped to the conclusion that the term 'Kelvin scale' had been abolished at the same time. You have convinced me with copious evidence that the latter term has not been abolished. --Heron 21:00, 4 April 2007 (UTC)
You’re right. Excessive redundancy fixed: second instance of “The kelvin is” replaced with “It is”. Greg L (my talk) 21:24, 4 April 2007 (UTC)

Conversion Chart

And to whoever screwed up the conversion table: Drag out a calculator and do the math yourself; it's not that complex. I checked the history log. At the exact moment I was actually making something (creating this image for the Close-packing article), you were over here fouling things up when all you needed to do was take the time to perform a simple, calculator-based sanity check on what was already here. Just so someone doesn’t have to restore the chart again, I’ll step you through how the now-restored math is correct. Examine the fifth conversion down in the chart:
To find Fahrenheit, From kelvin: °F = (K × 1.8) − 459.67
Plug a number into it, the melting point of water for instance…
?? °F = (273.15 K × 1.8) − 459.67
Try it. You’ll see it works as the answer is the correct 32 °F. Whatever you were copying elsewhere on the Web probably had different column headings on the chart (like, “To convert from…” or something like that).
Greg L (my talk) 00:25, 3 April 2007 (UTC)

I may be wrong (I haven't had my coffee yet) but I believe the equations for kelvin to celsius and celsius to kelvin are reversed in the chart. 0 degrees kelvin is absolute zero, 0 degrees celsius is the substantially higher melting point of water under standard conditions. The chart gives degrees celsius as "degrees kelvin MINUS the constant 273.15" and degrees kelvin as degrees celsius PLUS 273.15. Unless I am parsing this incorrectly, this places the freezng point of water at "absolute zero" and "absolute zero" at an impossibly lower temperature. I believe the constant 273.15 is correct, as kelvin and celsius use degrees of the same quantity, but it has been transposed in the chart. I don't want to chck out and correct the whole chart right now, but if I am right, and/or if the above poster is right, this chart needs substantial revision. 71.208.133.126 (talk) 18:51, 19 July 2010 (UTC)

I think you need that coffee. From the chart: taking 0 degrees celsius on the top line, equates to + 273 Kelvin, +32 degrees Farenheit, etc, which is correct. From the Infobox (Kelvin temperature conversion formulae), if we take 273.15 kelvin, the Celcuis equivalent = (273.15 - 273.15) = zero Celcuis, which is what we expect. Pyrotec (talk) 20:11, 19 July 2010 (UTC)

Georgia peach

This is a bad example, as Georgia is always capitalized, while kelvin is not always capitalized. --Scottandrewhutchins 20:19, 16 July 2007 (UTC)

SI prefixed forms of kelvin

What does this table listing everything from yoctokelvin (1e-24 K) to yottakelvin (1e+24 K) add to the article? I think it would suffice with a remark along the lines of as with other SI units, standard SI prefixes can be used with the K symbol, for example mK for millikelvin (1e-3 K) and MK for megakelvin (1e6 K). Temperatures of MK occur in <insert field of science here>. The whole idea of SI prefixes is that you can use them for ANY unit. Why not add such tables to Tesla (unit), Pascal (unit), parsec, and every other SI unit in existence as well? It makes just as much sense to mention that the word "temperature" can be prefixed with "high", "low" and any other adjective. It does not add any new information. Note that yottaparsec makes as little sense as yottakelvin. Is there any notable scientific publication that actually uses yottakelvins? If not, it should not be mentioned on this page, since Wikipedia is not a place for original research. Han-Kwang (t) 09:29, 23 August 2007 (UTC)

It doesn't add anything - it just bulks up the article a bit. --Yath 14:12, 23 August 2007 (UTC)
Agreed. The same argument holds for the articles on metre, joule, watt, kg, katal, coulomb, steradian, gray, radian, siemens (unit), henry (unit), weber (unit). Maybe it's good to build consensus about removing these tables. Han-Kwang (t) 15:44, 23 August 2007 (UTC)
I've nominated Template:SI multiples for deletion. I think the deletion discussion could serve as a place to build consensus. Han-Kwang (t) 16:02, 23 August 2007 (UTC)
Hankwang: You should read the article on original research as you don’t seem to understand what it means. The SI prefixes may be applied to any SI (or even non-SI unit of measure). The chart lists the full range of SI-prefixed forms of the kelvin. Further, it serves a purpose that a general link to SI prefixes can't do: it shows which prefixed versions of the kelvin (in bold) are the common one's that one might want to limit themselves to to avoid being too obscure. Yath: Finally, as had been explained in the editors’ note imbedded within the Kelvin table section, other articles link directly to this table. For instance, the Absolute zero article might mention 450 nk and the link takes the reader to the table. Articles would become bloated if they each had to individually explain every prefixed form of the kelvin. This issue is addressed most efficiently by including tables in their respective units of measure for other articles to link to. When you delete referenced sections like you did, you break numerous links in other Wikipedia articles because the referenced section is gone. Most importantly, you should read and comprehend what editors notes are saying. Ill-considered, wholesale deletions of entire sections of articles—especially when an editors’ note advised of the ramifications—are disruptive to others. Greg L (my talk) 17:39, 23 August 2007 (UTC)
This is the second time we've met up in an article and your immediate response is to revert me. Have you considered that my edits improve the articles, and that I don't perform them without good reason? --Yath 18:38, 23 August 2007 (UTC)
Don't play games. The last time you edited this article was nearly a year ago. Yet nine hours after I restored the table, you visit this article and delete the section. Perhaps this is shear coincidence; I doubt it. As regards "improving" articles, for the reasons clearly stated above, absolutely no; your deletion broke numerous other links. As I stated above, read and comprehend editors’ notes so you understand the ramifications of what you’re doing. If it can be convincingly demonstrated that you are just trying to be disruptive and are not making good faith edits, you might be blocked. Greg L (my talk) 18:44, 23 August 2007 (UTC)
Now let's keep a cool head, okay? Join the discussion on WP:TFD and contribute to a consensus for either keeping or deleting these tables. Han-Kwang (t) 20:02, 23 August 2007 (UTC)
I am keeping a cool head. Your baseless insinuation that I’m not does not establish you as the wise voice of reason. I will, however, visit the provided link. Greg L (my talk) 20:07, 23 August 2007 (UTC) P.S.: I added my comments to your nomination for deletion. Greg L (my talk) 20:52, 23 August 2007 (UTC)

I'm in absolute agreement that a full table with all SI prefixes is completely unnecessary and unwanted. There should absolutely be a reference to the "SI prefixes" page in wikipedia, which explains the usage of the prefixes, but it makes no sense to have it in every article with SI units. And especially not right at the very beginning of the page in the introduction. Bvis08 (talk) 00:13, 12 April 2008 (UTC)

SI table via template

I've reverted the table back to its Wiki table form. That is, after all, what Wiki table syntax is for: creating tables. Whereas templates are nice tool to have (thank you for creating the template) when creating new articles or brand new tables, they can not serve every need for every article. The main disadvantage of templates is that templates can be deleted at a later date and this would delete the table, would it not? Attempts to do precisely this—delete a table-generating template—have been attempted in the recent past after certain users objected to the very existence of SI tables. I guess I can’t ignore the preceding discussion topic (see above): as a matter of fact, once such user was you. I’m very pleased to see that you’ve had a 180° change of heart. I’m actually somewhat surprised at this, given your well articulated arguments above as to why they had no value whatsoever. You also advanced a good argument as to why they have no value in your nomination to have the SI table template deleted, (which was not affirmed by consensus). But I see that you now wholeheartedly embrace them. Unfortunately, the table you entered into this article had the symbols and names reversed. Here’s the original table, and here’s what you replaced it with. Notice the mix up. I’m actually rather surprised you hadn’t noticed that when you placed it here.

Please allow other users to use your recently created template for new projects and don't replace existing tables. Greg L (my talk) 22:55, 27 September 2007 (UTC)

I reversed to submultiples/multiples now and changed the headings. Please continue the discussion on Template talk:SI multiples. Han-Kwang (t) 09:59, 28 September 2007 (UTC)

Unicode use

Someone wrote the following in the section titled The special Unicode sign:

Unicode includes the "kelvin sign" at U+212A (K). However, the "kelvin sign" is normalized into U+006B (the ordinary Latin letter K), and is thereby seen as a (pre-existing) encoding mistake. The ordinary K should be used directly.[1]

Note that the cited reference, The Unicode Standard, Version 5.0, Chapter 15: Symbols (632 kB download, here) states precisely the following regarding the kelvin symbol:


(Emphasis added)

The section as originally worded misrepresented the facts and cites a reference that doesn’t support the statement. In fact, any computer capable of displaying Unicode should—and usually will—display the Unicode kelvin character.

Shown below is what my browser (Safari under Mac OS X) shows when the kelvin character and the letter K are showed side-by-side:

In fact, some browsers can display the kelvin character, which is coded in Unicode as &#x212A; . And in fact, some old browsers can’t handle Unicode and display weird, box-like characters. And in fact, others may normalize them. It is however, entirely incorrect to state that “[it is normalized and] is thereby seen as a (pre-existing) encoding mistake.”

It is obvious on the face of it that if one specifies a Unicode character, many computers will properly display them; that’s what Unicode is for after all. For instance, when I measure four microvolts (4 µV), the “µ” symbol is a special Unicode ‘micro’ symbol, which is different from the Greek lowercase mu character (μ). If you can read these characters and see the difference between the two, then your computer is properly displaying Unicode.

The end conclusion in the text that used to be in the article is the same one as in my new text: one should use a regular uppercase K so it displays properly on all computers. This is also consistent with the advise given in The Unicode Standard, Version 5.0, Chapter 15: Symbols.

Greg L (my talk) 21:39, 10 October 2007 (UTC)

It is actually entirely correct in saying that “[it is normalized and] is thereby seen as a (pre-existing) encoding mistake.” That's exactly what canonical normalization means; that Unicode encoded a duplicate of an existing character, either as an error, or as in this case, for compatibility with a different standard, and therefore it should be treated exactly same as that existing character (in this case, K).--Prosfilaes (talk) 03:33, 7 March 2008 (UTC)

References

  1. ^ "Symbols". The Unicode Standard (PDF) (Version 5.0 ed.). p. 493. ISBN 0-321-48091-0. Retrieved 2007-07-06. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)

electronVolts

Should we include eV in the table in this article? eV are a unit of energy, not temperature. While it may be convenient to use it as a unit of temperature in certain limited contexts, that's not generally the case, and this really will only confuse Wikipedia users. -Nathan J. Yoder 07:51, 27 October 2007 (UTC)

At least we should make it clear that without the Boltzmann constant the quantity calculus is inconsistent. --DrTorstenHenning (talk) 17:16, 27 November 2007 (UTC)
I removed it, since it only complicates things (and after all, if we have eVs, then we should also have cm^-1, J and all other units that have some sort of temperature equivalent).--141.154.246.202 (talk) 21:53, 28 December 2007 (UTC)

Population Inversion

It's been over 20 years since I studied any statistical mechanics, but I believe that population inversions, which can occur inside lasers for instance, have "temperatures" measured in negative Kelvin.

I'd like to see some mentione of the existence and interpretation of negative Kelvin temperatures. See Negative_absolute_temperature.

I have added that link to the "See also" section. Man with two legs (talk) 13:41, 4 April 2009 (UTC)

"In Short"

I corrected the use of the degree symbol here, as well as making it marginally more informative. However, I question the need for this section at all. dclayh (talk) 20:24, 24 January 2008 (UTC)

Heat vs. Temperature

The section labeled "Uppercase/lowercase, plural form usage, and written conventions" ends with the statement "an absolute unit of measure which can be manipulated algebraically (e.g. multiply by 2 to indicate twice the amount of heat)." This should read "multiply by 2 to indicate twice the amount of kinetic energy." As a change in the amount of heat does not necessarily correspond to a change in the temperature, even Kelvins, as in a phase change. elle317K (talk)

I agree with that, but it's a very subtle point: the change in temperature (e.g. doubling its absolute value) does not imply at all doubling the energy in the system -- you can even change temperature along an adiabatic process!
This is an old issue concerning the fact that temperature does not represent a fully-qualified physical quantity: in fact there is no sense in the statement "System A has twice the temperature of System B" in a unit-independent meaning. In contrast, for every other physical quantity Q like volume or mass, a statement like "System A has twice Q of System B" makes sense even without reference to any unit of measurement. Even more, it is just this property that make it possible to choose/define a physical unit for that quantity. Temperature is different, it is only a scale of comparison between systems which make order among them based on the heat flow direction: any non linear rescale of any good scale is good as well. (ok, absolute T is "more good" since it's linearly related to a physical quantity, namely energy...).
To make a long story short, the change you propose is by far better that the current statement, so I'm going to change the sentence the way you suggested, but there should be a place where the story is explained in its full length (like I did for it.wiki here. Ciao, Hronir (talk) 09:44, 29 November 2008 (UTC)

color temp

I restored this section. It was deleted by a user without any discussion. This is a common and important usage of the Kelvin scale. I don't accept the assertion that color temperature has no relation to kelvin. 61.114.206.106 (talk) 10:33, 23 November 2008 (UTC)

273.15 vs. 273.16

The article uses both the figures and 273.15 and 273.16. To the naive eye this looks like a typo or bad rounding; I found a forum thread elsewhere saying it's because the difference between the triple point and the freezing point. I think a few words on this distinction (if it truly exists) would be a good addition. --216.171.189.244 (talk) 00:50, 8 September 2009 (UTC)

Kelvin is defined to use 273.16 K for the triple point of water. However the degree Celsius is defined (in terms of kelvin) to be: T_Celsius = T_kelvin - 273.15. The Celsius definition uses the ice point and not the triple point. So I think the text is correct? but it is a bit confusing.
Apis (talk) 06:23, 28 October 2009 (UTC)
WP:Lead now modified. Pyrotec (talk) 10:39, 13 November 2009 (UTC)
As the triple point of VSMOW is at 273.16 K, the last sentence of Kelvin#Proposed_redefinition should be: "water will still freeze at 0 °C (273.15 K)." and not 273.16 K. Kelsklan (talk) 09:07, 24 April 2010 (UTC)
The paragraph that you are refering to, was added on 22 February 2010, and as you correctly pointed it is was wrong. The triple point of water is not the same as the freezing point; the latter being 0.01 K lower than the former. Pyrotec (talk) 17:08, 25 April 2010 (UTC)
The triple point is the freezing point for that pressure which is not atmospheric pressure. Jimp 11:04, 17 May 2015 (UTC)

Removal of discussion regarding Thomson's calculation of absolute zero

I removed the sentence noting the accuracy of Thomson's estimate of absolute zero. Since Thomson's data only had three significant figures, he could only estimate absolte zero to three significant figures - the agreement in the fourth significant figure was a fluke. Furthermore, as no refernces was given to this, so I must assume a bit of well-intentioned, but poor WP:OR.

History is confusing

The History section is confusing it seems to suggest there were two third revisions. The second Revision 3, mentions a 4th revision.

Mjoyce (talk) 00:13, 12 October 2010 (UTC) Confused of Sydney

Verification of general statements

This article is packed with very general statements, particularly about usages, such as abbreviations, capitalizations and the the like. None of those statements carry citations. Since I passionately hate the "citation needed" tag, I've not gone in and marked such spots. The number of such spots is so high that result of doing so would look like vandalism. But really, somebody either needs to back off on the general usage of unsupported generalizations such as:

"When reference is made to the unit kelvin (either a specific temperature or a temperature interval), kelvin is always spelled with a lowercase k unless it is the first word in a sentence.[6] When reference is made to the "Kelvin scale", the word "kelvin"—which is normally a noun—functions adjectivally to modify the noun "scale" and is capitalized."

or get busy on supporting them. Poihths (talk) 21:06, 23 September 2012 (UTC)

Kelvin is not better than Celsius

Celsius has a defined point. It's a constant. Kelvin doesn't have a constant or a base because it's point of "absolute zero" isn't defined, readable or able to be practically applicative. 58.7.161.46 (talk) 04:08, 9 December 2012 (UTC) Harlequin

The kelvin is an interval on an absolute temperature scale, it is defined by the Boltzmann constant.--Damorbel (talk) 08:14, 12 December 2012 (UTC)

One Ke·lvin is defined as the 1/273.16 water's triple point [solid-liquid-vapor equilibrium] (you don't need to define zero meter, zero ampere ... and also zero kelvin; all you got to do is "to measure" ). e.g. Sun's radiative power is 400 YW, dividing by its surface (take average diameter 1.40 Gm, gives you S = 6.2 Gm2 ) so its intensity, I = P/A would be 64.5 MW/m2, I /σ (stefan's cons. = 57 (nW/m2):K4) gives T4, so T4 = 1.13 P-K4 and T = 5.80 KK (famous 6000 °C sun surface temperature)

Tabascofernandez (talk) 23:28, 22 September 2017 (UTC)

I'm not familiar with water's triple-point, but will take your word for it. At some point in history (if not today) Celsius was zeroed at the freezing point of water at sea level, and 100 degrees was supposed to be the boiling point. When Kelvin began doing his experiments with extreme cold, it became apparent that thermometers of the time were not accurate enough to get the precise readings he needed, because the freezing and boiling points of water vary with air pressure, and air pressure is constantly fluctuating. Absolute zero, on the other hand, never fluctuates, so having an absolute scale was the only way to get truly precise measurements at such low temperatures. For measurements that don't need such precision, Celsius works just fine.
It's a very similar thing with pressure. When Kelvin, Edison and the others were experimenting with deep vacuums, normal gauges gave fluctuating readings, thus, like kelvin, torr was zeroed at total vacuum and redefined to equal 1/760 of a standardized atmospheric pressure. The only way to get precise, accurate reading was with an absolute scale. However, that is not always a better scale, because when measuring things like blood pressure, the differential pressure between the blood and the air is far more important than the absolute pressure, because the former determines the burst pressure.Zaereth (talk) 23:47, 22 September 2017 (UTC)
I understand what you're saying, but how do you define "zero ampere" when stray electrical currents are constantly moving around? How could you define an absolute zero speed without a completely stationary reference frame? Aside from meters, the measurements you speak of are not inherently absolute, so there is no way to apply such a scale to them. Zaereth (talk) 08:45, 24 September 2017 (UTC)

Plurals

The scale is Kelvin, but can the units ever be Kelvins, plural? Should temperatures be cited as "42 kelvin" or "42 kelvins"? (and is there a style guide source for this?)

I've never used kelvins in my life, but per this edit. Andy Dingley (talk) 09:21, 10 May 2013 (UTC)

yes it can indeed be plural (with lower case k). see the SI brochure. JMiall 10:14, 10 May 2013 (UTC)
My understanding is that you can use the plural form of kelvin for expressing differences (it is 20 kelvins between freezing and room temperature), but a temperature is expressed as 293 kelvin (singular), since it defines a point on the scale, not a number of intervals. Tarl.Neustaedter (talk) 17:58, 10 May 2013 (UTC)


What's the most CLEAR Non-Ambiguous symbol of Kelvin temperature scale? (°K) or (K)?

I was taught using the degree mark symbol (°) when using Kelvin scale, and now I understand why my past teacher taught me the pre-"13th CGPM in 1967/68" symbolization of Kelvin scale, with the degree mark (°K), but he never mentioned of the possible misinterpretation to "Kilo" interval scale to us until I realize it now.

After I browsed all thru this Talk page length, almost none mentioned the misinterpretation possibility of the letter "K" misusage between units and scales defined in SI standard, specifically the Metric interval scale standard.

My point is, how can you differ the "6900 K" written statement is for "6900 Kilo" (6.9 Mega) or for "6900 (degree) Kelvin"? This is a good example of my past confusion when reading the lamp color temperature of "Cool White" light color. "Kilo of what unit?" Until I realized later, it's referring to Kelvin temp-scale unit.


By using a degree symbol (°) before "K" letter, people can understand it's referring to Kelvin temperature scale (regardless of temperature absolutism/relativism/whatever issue - people have shown it can be inter-related to degree Celcius ['C] so easily anyway, so why SI in the 1st place removed the degree scale symbol if this can cause a mix-up with its own "Kilo" symbol? Ambiguity with Rankine scale? How come? it's written in "R" letter and not "K", for godsake! Just like all SI temperature scale units such as Celcius ('C), Kelvin ('K) belongs to this one too: the "temperature-scale" unit, so why "Kelvin" must omit the degree symbol while "Celcius" use it?). If you omit this degree symbol (sometimes replaced by ['] aposthrope/single quote symbol for chatting/fast-typing convenience, e.g: 'C for degree Celcius, 'K for degree Kelvin) people may mistake this with "Kilo" which is often abbreviated with uppercase "K" letter (in sync with SI recommendation itself) - even in practice, those who didn't know SI standard writings may mistakenly write it in lowercase letter "k" and think it refers to "Kilo" too (as mentioned in this Talk page debate, lower-cased "k" letter is used for Kelvin temp-scale too, making things worse).

FYI, SI defines all MAJOR/UP-SCALE intervals (multiple-upwards, e.g: 100x, 1000x) must be written in uppercase letter such as [K]ilo, [M]ega, [G]iga, [P]eta, and so on - and all MINOR/DOWN-SCALE intervals (multiple-downwards, e.g: 1/100x, 1/1000x) must be written in lowercase letter such as [c]enti, [m]illi, [n]ano, [p]iko, and so on. I'm sure at least one people remember this SI rule of its popular interval scale used throughout almost all the countries in the world (even USA mention their people wage/salary in "K" or "k" for shortening "Kilo", though along with UK, they are the last Imperial standard bastion/homebase).



So, I highly protest about the degree removal of Kelvin temp-scale unit, then recommend, and humbly suggest SI people for scientific world and people sake to revert to pre-"13th CGPM in 1967/68" convention, which used the degree symbol for Kelvin scale (°K, or 'K) to avoid misinterpretation with its own world-wide popular multi-interval scale, specifically the uppercase "K" letter for "Kilo" (1000x by basepoint). For this one, I agree with "Greg L" for using back the degree mark before "K" letter, but mainly for avoiding the misinterpretation reason, and nothing else (such as plural degree and lower/upper-case "K" letter issues).



Just to add comment to the "pluralistic" usage issue: it shouldn't be SI case though which deals only to metric standards and not grammatical/vocabulary issue between world languages, since it's merely English (Anglo-Saxonian base) grammatical/vocabularic problem that any plural object must be suffixed by "s", and reference to human/object must be gender-based/bias (he/she/his/her, etc - i.e: why reference to a ship must be 'her' in first place? can't it just be 'it'? can we melt down the 'he/she' text into just 'it' or similar short genderless singular word to avoid gender-bias and too-long-to-type problems?), since some nations (other than UK/US) have no obligation to mention things in plural form, thus saves text space and brain utilization so much :).

For example, I would highly prefer "123 Kilo" rather than "123 Kilos", since both refers to the same idea, it states the unit name clearly/distinctly w/o possible misusage for some non-English speakers (e.g: "1 Kilos" instead of "1 Kilo"), and this will save much lines of programming codes needed to determine whether the number is over/below 1 and when it's true then append "s" letter after the "Kilo" text (only dumb can-not-count-number people can't figure out it's plural or not without the suffix "s" - only when a clearly-stated number is not involved/stated then the "s" suffix can be quite useful to mention the plural degree of object family/class). It's also better (no mix-ups), shorter, and easier to write (273 'K), (273 °K), (273 [degree] Kelvin) instead of (273 K), (273 Ks), (273 degrees Kelvin), (273 [degree] Kelvins). This way the unit name will stand out clearly and readable correctly w/o pluralistic thing involved, thus prevents possible unit name misuse/wrongly-used later on some non English-aware countries/nations. What if the people in far far far Asia (for example) w/o plural-reference awareness think the unit name is "Kelvins" instead of "Kelvin" (or the scale name is "Kilos" instead of "Kilo")? Does SI board/people ever consider that possible misuse also?



"A global standard should be FREE from possible MIX-UPs/MisInterpretations/Misuses, especially with its own (already) defined units/scales/markings." - [Ois1974].



If lowercase "k" letter would be used for Kelvin temp-scale then please do a cross-check 1st with SI own metric units/scales - has it defined yet already? If not, then it can be used as one of SI scale/unit standard, otherwise try other ways to define this clearly without possible mix-ups with SI own standard units/scales.

It's unbelievable how this misinterpretation/mix-up issue can arise on the global popularly-accepted SI metric standard, in form of terms/writings collision in its own defined standard - and no one (SI standard users) even mentioned about it a bit.

--->[Ois1974 @ 2013-07-20 Sat] — Preceding unsigned comment added by 114.79.3.122 (talk) 08:36, 20 July 2013 (UTC)

Wikipedia is about collating information that already exists, it is not a forum for personal viewpoints. I suggest that you visit the BIPM website to see how best to progress your views, though I don't guarantee that it will be of any use. Martinvl (talk) 09:30, 20 July 2013 (UTC)
Yes, I knew that "WP only gathers links and info from existing others (or not the primary original source of info)" stuff already. But please tell me, why people above/before me use this TALK page for expressing their views also just like me? If they were for article's editorial reasons, why using this TALK page instead of the special editorial board section? They use this TALK page for discussing the related article and forbid themselves from ruining the main article with comments (they know how to behave here) - this TALK page is like a mini discussion forum for them since Wikipedia doesn't provide other right media for discussing the article and expressing their views about the article contents. If you have read contents of many articles' TALK pages in Wikipedia, you know what I'm talking here. May be Wikipedia want to try to start as the first TRUE interactive online encyclopaedia in th world? In offline world, people are usually making sidemarks/sidenotes on their science bibles, the encyclopaedia books, or whatever they are for correcting things obsolete/contradictive to current views or standards - In online world, people now can interactively making online suggestions/corrections to their shared online encyclopaedia 'books' like Wikipedia here (in form of suggestions to board of editors or whatever it might be called). Why would Wikipedia restrict itself from being the BEST MOST TRUE INTERACTIVE shared online Encyclopaedia, and the #1 recommended and referenced by ALL scientists/knowledge-seekers in the world? "Want to advance your knowledge FAST and share your nerdy (constructive) opinions FREEly without those stupid (deconstructively-commenting) trolls? Simply quantum-jump yourself to Wikipedia!" - A good educational ad, eh? :) Have you ever think kind of the possibilities this far? Watch out, others may snatch this idea quickly and start it anyway, sooner or later! A brand new version of social-media in a TRUE scientifical/knowledge-base taste, and they have their own (#1) online encyclopaedia for global references/standards used by most scientists and teachers in the world, why not?!

Wikipedia is highly regarded as (quite reliable) source/resource of knowledges by some people inclined to science/education world. If those who think they are so clever and sitting on boards of standards never think about reading Wikipedia's TALK page for gathering people comments/expressions/whatever to make for better standards/whatever to the world, then they should step down and replaced by some clever people commenting here (or from editors board of Wikipedia). If I were one of those high board committee or whatever dealing with global/regional standards, I would read public/scientific forums related to the (open) standards, including this Wikipedia TALK page, for external source of informations, and for decision making, for current and future possible issues. As you said also, going to BIPM won't guarantee anything (is this also picturing how 'snob' they are like commonly assumed by people regarding boards of something? Only hear themselves and not others?), why would I bother going there on first place? At least one clever and honored by boards of standards like BIPM could carry these people comments and suggestions to the boards and discuss those for better CLEAR standards. But I might pay a visit there on my leisure time though, to see how many people visiting and commenting there and comparing to Wikipedia visits by people. It's amazing to see how clever these people are commenting in Wikipedia, so smartly serious (as it should be here) and forgetting to trash this page with stupid short chat-like and/or deconstructive trolling comments (such as: "You imbecile luddite must..., etc, etc") just like other public forums (moderated/not) - they know how to behave/socialize here in a knowledge-base media. Thank you for not trashing and vandalizing this TALK page, all smart/clever people! Thanks again in my humble deep honor! --->[Ois1974 @ 2013-07-21 Sun].

Just in case someone else reads the rant at the top of this section and wonders if it should be taken seriously, please note a few errors made by that original poster. (1) SI symbols for multiples less than a million are LOWERCASE, e.g., kg=kilogram, hm=hectometer, etc. Above one million, they become capital: Mg=megagram, GW=gigawatt, etc. So, the OP is fundamentally confused about capitalization conventions for SI. "K" can never be mistaken for "kilo" because the abbreviation of "kilo" is lowercase "k". (2) "Kilo" is not a unit. In many countries, people say "kilo" when they really mean "kilogram," and the context is clearly about weight. But the standard SI symbol for that is ALWAYS kg, not k or K or anything else. (3) The OP worries that someone might think that "kelvins" is a unit. Well, it IS the plural of the unit "kelvin," as discussed in the article. (4) There are actually other examples of SI symbols which would be better examples of the OP's problem: G = Gauss as well as "giga," T = Tesla as well as "tera", etc. But the problem is, like "kilo," these are only PREFIXES and thus can never be encountered alone. So, "T" by itself as a derived unit MUST mean Tesla, not just "tera" -- tera... what? Similarly, "K" must mean kelvin.
In sum, the OP requests that the SI system be free from misinterpretation, but it already is -- BY DESIGN. The people who created the standards thought long and hard just to avoid all the sorts of confusion the OP thinks exists... except it only exists because he/she doesn't understand that correct use of the SI system. 98.25.50.67 (talk) 21:27, 26 April 2014 (UTC)
this unit is named after him (like volt, watt, etc) and he didn't inroduce it as Celsius and Fahrenheit did. so "degree" isn't needed. [compare: degree of Oechsle, degree of Delisle, degree of Plato ...]

Tabascofernandez (talk) 23:23, 22 September 2017 (UTC)

Capitalisation in the table

The conversion table says "Kelvin" with a capital K. Shouldn't it be lower case?212.9.31.12 (talk) 09:23, 10 December 2013 (UTC)

Template

The conversoin template spells Kelvin instead of kelvin, due to the use of the page title as a parameter. Nijdam (talk) 12:48, 2 May 2014 (UTC)

Fixed

Well, "to/from Kelvin" could be interpreted as short for "to/from the Kelvin scale" but it's been changed to "to/from kelvins" anyway. Jimp 10:59, 17 May 2015 (UTC)

Does "degree" really indicate an arbitrary reference point?

The article states:

The omission of "degree" indicates that it is not relative to an arbitrary reference point like the Celsius and Fahrenheit scales (although the Rankine scale continued to use "degree Rankine"), but rather an absolute unit of measure which can be manipulated algebraically (e.g. multiplied by two to indicate twice the amount of "mean energy" available among elementary degrees of freedom of the system).

That sentence implies that the term "degree" somehow distinguishes scales with an arbitrary reference point from scales with an absolute reference point. If that is true, it needs a citation. Wikipedia's article for degree gives no indication that the term has any such meaning. -TC 98.108.203.102 (talk) 00:11, 11 February 2016 (UTC)

I have seen that explained just that way in many different scientific books. (See my comments near the top of this page.) However, the thing to understand is that the English language is very fluid and constantly changing. The word "gear" is one of my favorite examples. In Old English this meant "habits and mannerisms." In Middle English it referred to "any goods, supplies or arms carried with a person." In the renaissance it became "any internal workings of a machine." It was only in the last century that a gear became "a wheel with interlocking teeth." Scientific words are adopted by the general population and altered all the time, and visa versa.
This notion of removing the term "degree" is really an attempt to change the unit from a circular reference to a linear one. For instance, we don't speak of degrees of inches or meters, degrees of weight, pressure, etc... The term "degree" was adopted from measurements of arc, which are not specific to any actual distance. (The distance of one degree is dependent on the size of the circle, or the "defining parameters.") I have no idea why it became used in temperature measurements at all, but it did.
In the scientific sense, removing the term "degree" gives it the sense that is fully defined measurement with a very specific "distance." (I'm using the term "distance" in a rather symbolic fashion here.) In contrast, the "length" of one unit of Celsius depends on both the freezing and boiling points of water. Because these points change ever so slightly depending on air pressure, the unit or "degree" of Celsius is not a fixed one. (The "distance" changes depending on air pressure.) Having 2 zero-points, one fixed and the other not, provides that circular parameter. Scientists wanted to make a distinction that the distance of one kelvin was always the same. They did the same thing with Torr, because mmHg was constantly fluctuating with air pressure, and made deep vacuum measurements nearly impossible. When working with extreme cold, the same problem became evident.
Nearly all of the scientific data has caught up to this distinction, but the general population has not, and may never. There are no set rules for how units of measurement must be written. Each unit has its own way of doing things, and that doesn't alter how the term "degree" is used in other units. Like all language, these things are something society as a whole just makes up as they go along through a process of groupthink. Some catch on and some don't, but that is a very condensed explanation of what you can find in most books. When I get some more time, I'll be glad to add sources and maybe a little clarification. Zaereth (talk) 01:21, 11 February 2016 (UTC)
Thank you for the well-considered reply. I must agree with your persuasive argument that language is fluid and constantly changing, but I'm not sure that is relevant here. The bottom line is that if the article explains why "degree" is omitted from the unit name and symbol, then that explanation must either be intuitive or must be supported with a citation. The current explanation is neither intuitive nor supported. -TC 98.108.203.102 (talk) 20:34, 15 February 2016 (UTC)
These things are rarely intuitive. Just look at the etymologies of "moose," "bird" or "dog," or the scientific vs the general definition of glass, to name a couple. You are more than welcome to find some citations and make changes that will make the text more understandable and well defined. You can find lots of reliable stuff on google books. Personally, I'm extremely busy and only spend about ten minutes a day on the computer anyway (this is just something to do when I'm on hold) so I have no time to do it right now. I only have this article on my watchlist because I added a wikilink once and haven't de-watchlisted it yet, but etymology fascinates me, so I decided to answer your question. Like I said, I may be able to get back to this in the future, but not now. Zaereth (talk) 21:49, 15 February 2016 (UTC)
The issue with your explanation though Zaereth is that while it does make sense at a glance, celcius in practical usage is a set measure, kelvin itself is based upon celcius, what constitutes 1 increment in the measurement is thus abitrary (Why is the split between Absolute zero and the triple point 273.16 and not 200 or 500 for example) and both measures have changed and will change over time.
It seems more like a random and pointless change than anything... 2A02:C7F:A41A:AA00:94E8:D26A:2E13:4502 (talk) 14:44, 8 September 2016 (UTC)

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Lowercase kelvin

According to the CIPM committee, the unit kelvin is lowercase, so I changed all references to it to lowercase in the article. That same reference used, e.g., 144 kelvins; I didn't realize the the plural form is indeed different, with that added "s".

The statement below seems dubious to me, so I removed it. If it is reinstated, I hope an appropriate reference is included.

When reference is made to the "Kelvin scale", the word "Kelvin"—which is normally a noun—functions adjectivally to modify the noun "scale" and is capitalized.

In the context of referring to the scale proposed by Lord Kelvin, that might be called the Kelvin scale. However, in the context of referring to a scale based on the kelvin unit, that would surely be the kelvin scale. --Christopher King (talk) 15:37, 12 May 2017 (UTC)

I reverted it. The name of the scale is unaffected by that CIPM brochure, it refers specifically to the use of the unit itself. Common usage in current published material is to refer to it as the Kelvin scale. Whether the scale is named after the unit or the Lord is a angels-on-a-pinhead question, but current published material uses capitalization there. Tarl N. (discuss) 01:02, 13 May 2017 (UTC)
In which case the statement about capitalization should be cited to the "current published material". --David Biddulph (talk) 01:50, 13 May 2017 (UTC)
Possibly. The change in the unit name being lower case "kelvin" dates back to the 1980s (my recollection is that we changed from degree Kelvin (˚K) to kelvin (K) at the same time), and usage I see in the various recent textbooks all use "Kelvin scale" while using "kelvin" as the unit. The uncited statement could be removed, because its uncited - I restored it because it provided an explanation for a non-obvious typographical usage. Either way, there is no justification for changing the name of the scale, the literature doesn't seem to reflect it. Tarl N. (discuss) 02:24, 13 May 2017 (UTC)

Temperance & temperation

temperance, T, is measured in Ke·lvins, while temperation, ΔT = T − T0, where T0 = 273.15 Ke. so normal body temperance would be 310.15 Ke, while its temperation is 310.15 − 273.15 = 37 Ke. so we can easily use kelvin unit in everyday expressions such as weather predictions etc. e.g. my room "temperation" is 25 Ke.
Tabascofernandez (talk) 23:16, 22 September 2017 (UTC)

Phraseology

@Dondervogel 2: just marked a sentence as dubious, with the edit comment: I don't buy this; "273 kelvin" is way more common than "273 kelvins".

I don't have a cite, but I'll comment that as a current student, but someone who grew up knowing kelvin used degrees, calling the triple point of water 273 kelvin or 273 kelvins is purely a matter of where I'm swallowing the "degrees". Is it "273 degrees kelvin", or "273 kelvin degrees", where I'm keeping the degrees silent? In the former, the plural gets eaten, but in the latter, it's natural to move the plural to the remaining word. Certainly in offsets (Nitrogen liquifies 13 kelvins cooler than oxygen) the plural tends to be used. Some people would prefer "degrees" be used in that sentence, but being in an a region where Fahrenheit is used, the term "degree" is avoided unless a qualifier is added. Tarl N. (discuss) 23:38, 25 February 2018 (UTC)

In my experience (confirmed by Google Scholar [3]) people do not say "273 kelvins" when referring to zero degrees Celsius, but "273 kelvin", and this is my main point. There's no "degrees" to swallow because there are no degrees Kelvin, just kelvin (or kelvins). Dondervogel 2 (talk) 00:14, 26 February 2018 (UTC)
There are a lot of over-conceptualized arguments for the use of non-pluralized "Kelvin" for temperature. Some would argue it's a unit and not a degree, while others say a degree is also a unit. Other units like Millimeters, Radians, or Pascals are pluralized, while still others like Torr, Bar, and Rankin are not. Like most language, this doesn't seem to have developed with any rhyme nor reason other than "that's the way it turned out." As far as I can tell it is simply a matter of convention amongst scientists to use the non-pluralized form for temperature and quite often the pluralized form for color temperature (possibly as a mere matter of convenience, who knows). Or possibly, as Tarl points out, for differential temperature as well, just because it flows off the tongue better. I don't have any sources that actually say this, I've just noticed in books that it is more common than not to use them this way.
That's the trouble with English, because you can't always apply rules like pluralization to everything equally, across the board, and expect everyone else to follow. There are always exceptions to every so-called rule, because that's just the way we speak. (We could just as easily say "units Kelvin", but nobody does ... except I guess in cases of division, as in "per units Kelvin".) Zaereth (talk) 19:59, 26 February 2018 (UTC)

kilowatt.hours?

A little off-topic, but has anyone come across kelvin as an historic synonym for kW.h, the unit of electrical energy used by electric supply companies for charging consumers? In this 1919 Australian report of a customer illegally diverting power (electricity for lighting purposes being charged at a higher rate) it is so used, and their equivalence noted here. Doug butler (talk) 00:18, 13 May 2018 (UTC)

Nope. It was certainly never standardized, and from the pointers you give, appears to have been a purely Australian usage, which fortunately disappeared almost without a trace. Tarl N. (discuss) 01:07, 13 May 2018 (UTC)

Is there a name for the constant 273.15?

I wonder if there is a name for the constant, 273.15? So you don't need to utter the value, which is a bit cumbersome to do, each time when you need to mention it. --Roland (talk) 06:37, 14 February 2019 (UTC)

From everything I've read, that's called the "freezing point of water" ... at standard atmospheric pressure of course. The triple point is slightly higher than that, which is where water can exist in all three states (solid, liquid, and gas, or as we Alaskans call it, slush) at the same time. (Slightly higher than the triple point is the melting point of ice.) Zaereth (talk) 19:22, 14 February 2019 (UTC)