Talk:Glossary of mathematical symbols

says who?

The lead includes the claim the standard typeface is ... upright type for upper case Greek letters. Really? According to what standard? Dondervogel 2 (talk) 09:37, 11 January 2025 (UTC)

See Donald Knuth's TeXbook. Also, if you type <math>(\Gamma,\gamma)</math> you get $(\Gamma ,\gamma ).$ This show that LaTeX, the standard fo mathematical typesetting, implements this standard by default. D.Lazard (talk) 15:43, 11 January 2025 (UTC)

I was under the impression that international (ISO) standards required upper case Greek symbols to be in italics. Hence the tag. However, a brief search did not reveal evidence to support my impression. I'll come back here if I find something. Dondervogel 2 (talk) 15:55, 11 January 2025 (UTC)

In any case, ISO is a standard developped for engineering and is generally not accepted by mathematicians. D.Lazard (talk) 22:10, 11 January 2025 (UTC)

That might be your opinion. I don't share it. In any event, I've found the standard I was looking for (ISO 80000-1:2002), which confirms my impression is correct (indeed, it is likely the source of that impression. I'll come back with the details. Dondervogel 2 (talk) 22:28, 11 January 2025 (UTC)

In any case, ISO is a private company, and its standards apply only to corporations and communities that decide to apply them. For the typography of formulas, it is not the case of the mathematics community, and more generally the academic world. It is also not the case of English Wikipedia, see MOS:MATH#Greek letters. D.Lazard (talk) 10:46, 12 January 2025 (UTC)

Your 'not invented here' attitude has no bearing on the relevance of ISO. I can clarify here if you wish, or just edit the article to correct the imbalance. Which do you prefer? Dondervogel 2 (talk) 13:36, 12 January 2025 (UTC)

On the contrary, you appear to be applying "not invented by ISO". Although I am a strong supporter of international standards in general and ISO in particular, context matters. Mathematics has long established customs and practices and the form that a symbol takes matters. The "same" letter presented in different typefaces has different meanings. ISO has no interest in this level of detail and you should not try to enforce it outside its domain. See Scope creep.

Put simply, you will not get consensus for such an insertion. 𝕁𝕄𝔽 (talk) 17:12, 12 January 2025 (UTC)

Three questions:

1. If ISO has no interest in this level of detail, why does it publish ISO 80000-2:2019 Quantities and Units - Mathematics?
2. What insertion are you suggesting there would be no consensus for?
3. Are you saying that the scope of this article is limited to mathematical symbols not defined by ISO?

Dondervogel 2 (talk) 17:32, 12 January 2025 (UTC)

Saying otherwise: for that matter, ISO 80000-2:2019 is a WP:Primary source; so, for being acceptable, one needs a reliable WP:secondary source that discusses the matter and concludes that it applies in mathematics. Without such a secondary source this is WP:original research produced by ISO consortium, and so, ISO 80000-2:2019 cannot be accepted as a source for mathematical articles. D.Lazard (talk) 21:51, 12 January 2025 (UTC)

Pointing out the existence of ISO 80000-2, while observing that compliance with its requirements would conflict with Donald Knuth's TeXbook, does not seem like WP:OR to me. They are simple and indisputable facts. Dondervogel 2 (talk) 06:14, 13 January 2025 (UTC)

Huh, what? You can indeed deduce facts via original research—surely this would be the goal much of the time.

This is functionally identical to the fourth example given at WP:SYNTH. Likewise, it would be original research, and Wikipedia does not publish original research. I am interested a bit in whether you have heard the phrase "verifiability, not truth" here before. Remsense ‥ 论 06:17, 13 January 2025 (UTC)

If something is obvious to anyone who reads and understands the sources that are supposed to support it, then it's not SYNTH. Dondervogel 2 (talk) 06:56, 13 January 2025 (UTC)

Well, no. Any claim not directly supported by a particular RS is original research, and that's pretty incontrovertible. Sometimes we feel like doing it anyway because we feel it to be obvious or otherwise harmless, but the fact remains no matter how many smarmy sections we pen in an essay about it. (Cards on the table, if I could ask God to send a little solar flare that results in exactly one page getting erased from project space forever, I might just pick this one. I disagree at least in part with most of the sections, and I think at best it encourages a proudly sloppy approach to research, and at worst it is directly contradicted in spirit by the plain meaning of our core content policies. Using IAR as a thumbs-up for SYNTH if you feel like it is just...gah, I have to stop now.)Remsense ‥ 论 06:59, 13 January 2025 (UTC)

A more appropriate reply would have been "Well, yes". The words you were responding to were not my interpretation but were copy-pasted from not SYNTH, so perhaps I should have put them in quotation marks. Try it like this: "If something is obvious to anyone who reads and understands the sources that are supposed to support it, then it's not SYNTH." Dondervogel 2 (talk) 07:25, 13 January 2025 (UTC)

Firstly, yes it is! Original research can be as obvious as you like.

Secondly, this argument isn't meaningful because I don't know what extrapolations and deductions would be obvious to everyone, and neither do you. The best I can do is sticking to tertiary analysis that presents only those claims that sources themselves say directly. That's the point of the policy as far as I can tell, but everyone's got a few edge cases they think are obvious or harmless. Remsense ‥ 论 07:32, 13 January 2025 (UTC)

Not being made of money, I have no idea what is in ISO 80000-2, perhaps you will enlighten us? But the abstract seems to suggest it is nothing more than a glossary of symbols used in Mathematics that may be relevant to science and technology, not a standard for mathematical typeface choice irrespective of context. The abstract reads:

This document specifies mathematical symbols, explains their meanings, and gives verbal equivalents and applications.
This document is intended mainly for use in the natural sciences and technology, but also applies to other areas where mathematics is used.

That second statement, I suggest, tells us all we need to know.

No, the scope of this article is the set of symbols used in mathematics. The set of mathematical symbols listed in the ISO standard is almost certainly a subset of it: if you find any that are not, then it is probably an oversight that should be rectified.

You will need to quote verbatim the relevant text from the standard if this is to be taken any further because right now it is impossible to take it seriously. I think it most unlikely that ISO would presume to contradict the thousands of mathematics publications and their authors. 𝕁𝕄𝔽 (talk) 00:41, 13 January 2025 (UTC)

You seem to be saying that mathematics, once applied to the physical sciences, is no longer mathematics. That makes no sense to me, and I doubt it is your intended meaning. Please clarify.

Happy to provide examples. There are likely others, but one is the ISO requirement to use italics for upper case Greek characters when they represent variables. I'll return with a verbatim quote. Dondervogel 2 (talk) 06:23, 13 January 2025 (UTC)

Even with a verbating quote, ISO's original research would remain original research. D.Lazard (talk) 09:51, 13 January 2025 (UTC)

No, WP:NOR only applies to Wikipedia itself. OSI standards are WP:RSs and are generally written by subject experts. (Though, if Dondervogel has read it correctly, clearly not mathematical subject experts.) 𝕁𝕄𝔽 (talk) 12:00, 13 January 2025 (UTC)

No, what I am saying is that ISO appears [rather astonishingly] to be specifying the form that mathematical symbols should take when used in science and technology. It is not (I hope!) purporting to tell mathematicians what symbols they should use, for what purpose, with what meaning, in which typefaces and fonts. 𝕁𝕄𝔽 (talk) 11:57, 13 January 2025 (UTC)

Ah, OK. I knew I must have misunderstood. Your first sentence makes complete sense to me. The second one is less clear though. ISO 80000-1 (and ISO 80000-2) do not tell anyone what do do. Instead they provide requirements and recommendations for those who wish to follow the standard on a voluntary basis, including any mathematicians applying they skills to science and technology. As far as I can tell, the present article is not limited to pure mathematics, which means the scope also includes applied mathematics, and ISO 80000 is most relevant to the latter scope. Dondervogel 2 (talk) 12:08, 13 January 2025 (UTC)

Well let's see the quote. But I really can't see it meriting more than a footnote. See WP:UNDUE.

But cheer up, it could be worse: in the days when typesetters had to deal with handwritten manuscripts, this is what they were up against: The printing of mathematics (Oxford University Press, 1994) The only reference to upright v slanting Greek is to π on page 2: upright when used as a constant, slanted when a variable. 𝕁𝕄𝔽 (talk) 13:09, 13 January 2025 (UTC)

LoL. ISO's position is that all constants (1, 2, 3, ..., pi, e, i, etc) are upright, which is consistent with the OUP 1994 advice. It's probably to avoid use of the symbol pi for anything other than it's usual 3.14159265...

A footnote might work. I still need to find the text for you, although you can find a preview at ISO/IEC 80000 Dondervogel 2 (talk) 15:06, 13 January 2025 (UTC)

I pointed out the existence of this discussion at ISO/IEC 80000 Dondervogel 2 (talk) 18:03, 13 January 2025 (UTC)

• Here's the verbatim extract (clause 7.1.1) from ISO 80000-1:2022

Symbols for quantities are generally single letters from the Latin or Greek alphabet, sometimes with subscripts or other modifying signs. Symbols for characteristic numbers, such as the Mach number, symbol Ma, are, however, written with two letters from the Latin alphabet, the initial of which is always capital. It is recommended that such two-letter symbols be separated from other symbols if they occur as factors in a product.

The quantity symbols shall be written in italic (sloping) type, irrespective of the type used in the rest of the text.

The quantity symbol is not followed by a full stop except for normal punctuation, e.g., at the end of a sentence.

Notations for vector and tensor quantities are given in ISO 80000-2.

Symbols for quantities are given in ISO 80000-3 to ISO 80000-5 and ISO 80000-7 to ISO 80000-12 and IEC 80000-6 and IEC 80000-13.

No recommendation is made or implied about the font of italic type in which symbols for quantities are to be printed.

• Clause 7.4 contains the Greek symbols in four different forms (upper case v. lower case, italic v. upright).
• Annex A.5.3 includes some examples (see ISO 80000-1).

Dondervogel 2 (talk) 15:19, 13 January 2025 (UTC)

So coming back to your statement that kicked off this discussion (I was under the impression that international (ISO) standards required upper case Greek symbols to be in italics.), can we now say that your recollection was mistaken, that the rubric only applies to quantities? (How does it define quantities? When or where are uppercase Greek letters used? (not micro- or nano-, obviously). But in any case it certainly can't be declared to apply of generic use of Greek letters in mathematics (pure or applied – or physics, for that matter), but there may be specific cases (such as?). --𝕁𝕄𝔽 (talk) 18:31, 13 January 2025 (UTC)

Argh! Perhaps everyone should take a step back. Firstly, Donald Knuth is evidently talking about (his?) TeX specifically (the statement needs rewording to make this restriction clearer, and IMO does not belong in the lead). Secondly, ISO is, as has been noted, a recommendation that can be followed by those who choose to (it acts to help produce more uniform presentation). Thirdly, and most importantly, this article is clearly just an informal glossary with no claims made about general applicability, and should in no sense claim to describe a uniform standard – at best, it could serve as a guide for the MoS to reference, i.e. usable in the domain of WP, and not claiming to apply anywhere else other than possibly describing specific uses that occur. All this talk of OR, verifiability, etc. seems to be misplaced. —Quondum 18:43, 13 January 2025 (UTC)

My recollection was correct, though I might have phrased it better. I was referring to any upper case Greek symbol representing a quantity (the example given by ISO 80000-1 is Φ, but it can be any one of 24 upper case Greek characters). The point is that ISO 80000 requires the character to be italic (Φ), not upright (Φ).

I believe the full set is ΑΒΓΔΕ ΖΗΘΙΚ ΛΜΝΞΟ ΠΡΣΤΥ ΦΧΨΩ. If any of those 24 characters are used to represent a quantity (as opposed to an object or concept or operator), compliance with ISO 80000 means the symbol for that quantity would be italic. As an example, imagine the quantity Χ is defined as the sum of Ψ and Ω. The equation relating these three quantities is Χ = Ψ + Ω and not Χ = Ψ + Ω.

I hope this clarifies. Dondervogel 2 (talk) 19:25, 13 January 2025 (UTC)

I have edited the lead. The statement being commented on in this thread might or might not belong: I'm not sure myself, so I've left it as an invisible comment, in a less contentious form that simply describes the different conventions, in case someone wishes to change it into visible text. —Quondum 00:05, 14 January 2025 (UTC)

Thank you. Your edit completely addresses my concern. Dondervogel 2 (talk) 08:52, 14 January 2025 (UTC)

Lazy-S redirects here, but 'lazy' not mentioned

Page Lazy-S redirects here, but the page doesn't mention 'lazy' so searching within the page is no help. I'd expect any page redirection to ideally anchor to the relevant section, and for the page to mention the term. Ralph Corderoy (talk) 16:40, 18 January 2025 (UTC)

According to this site, it represents the inverse hyperbolic cosine. Dondervogel 2 (talk) 17:09, 18 January 2025 (UTC)

Lazy-S is not a mathematical symbol. At least, it is so rarely used that no mathematical article of Wikipedia mention it. So, I have redirected Lazy-S to Lazy S Ranch. The Unicode name of the symbol ∾ is "inverted lazy S", but the only mention of this symbol name that I have found in Wikipedia is in List of XML and HTML character entity references. As there is no other content related to this symbol in this article, this is not a relevant target. D.Lazard (talk) 19:23, 18 January 2025 (UTC)

Equals with asterisk?

I see that U+2A6E ⩮ EQUALS WITH ASTERISK (&easter;) has a html mnemonic but is not mentioned in this article. Significant? 𝕁𝕄𝔽 (talk) 12:11, 20 January 2025 (UTC)

What does it mean? Dondervogel 2 (talk) 12:19, 20 January 2025 (UTC)

This article mention only symbols that have a common mathematical usage. Having a html mnemonic is not sufficient for being listed here, even if the Unicode name consitsts of mathematical terms. D.Lazard (talk) 14:31, 20 January 2025 (UTC)

Ok, it was just curiosity, because I had never come across it before. The fact that it has a html shortcut suggested that it might have some special significance. (I see that Equality (mathematics) doesn't mention it either, so no point in spending any more time on it.) End. 𝕁𝕄𝔽 (talk) 16:42, 20 January 2025 (UTC)

Recent reversion

I recently added the prime power divisibility relation symbol to the glossary, with a source, only to have it promptly reverted. While I concede that it's not the most common notation (in fact, I added it for that very reason; it took me ages to find it defined anywhere after I saw it in multiple academic papers without being defined), I take issue with @D.Lazard's rationales on the following grounds:

1. Nowhere on MOS:GLOSSARIES (at least that I can see) does it mention that the defined terms actually have to be used elsewhere on Wikipedia. (In fact, it would make no sense to reference many of the terms in a glossary on other pages in various topics, like fictional universes.)
2. MathWorld may not be the best source, but at least I provided a source. The vast majority of the glossary is unsourced. I challenge WP:WPMATH to actually source the definitions on this article before calling out someone new to the WikiProject for providing a "weak" one. Though some symbols seem obvious to anyone with at least basic math knowledge, practically none of the entries cite anything that attests to their "common usage", or even their existence. This whole page is a bunch of hot air as far as WP:V goes.

Lack of sourcing was an issue that kept this page from being promoted to FL. In 2007. The issues are old enough now to vote and drink in many countries. Please fix them. -happy5214 11:45, 5 May 2025 (UTC)

WP:LISTGLOSSARY says Glossaries – alphabetical, topical lists of terms, rather than of notable entities – are encyclopedic when the entries they provide are primarily informative explorations of the listed terminology, pertaining to a notable topic that already has its own main article on Wikipedia.

When elaborating this article, the choice has been done to restrict the glossary to symbols commonly used in mathematics, and to deport citations to WP articles where the symbol is defined and used. Indeed the mathematical coveage of Wikipedia is sufficient to insuring that a symbol that is not used in Wikipedia is not commonly used. This choice was done indepedently of the above quotation, but is validated by it.

Providing a single source is never sufficient for inclusion in Wikipedia, especially when the source is as unreliable as MathWorld.

All of this implies that, for adding a glossary entry for prime power divisibility, you have first to write an article or an article section on this subject that has a sourced content and a reliable source for the notation. Then it will recommended to add the symbol to the glossary. But before that, I'll oppose to edits such as yours. D.Lazard (talk) 13:35, 5 May 2025 (UTC)