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October 29

E-Z notation: why not just use "cis" and "trans" as infixes?

(Z)-1-Bromo-1,2-dichloroethene could just be bromotransdichloroethene.

Are there any cases in which cis-trans notation would still be ambiguous if -cis- and -trans- were used as infixes before pairs of substituents? For example, (Z)-1-Bromo-1,2-dichloroethene could just be called bromotransdichloroethene. (Note the advantage of also being able to eliminate the numeric infixes in that case, since 1,1-dichloro wouldn't be transdichloro.) Likewise, the haloalkene with SMILES C(/Cl)(\Br)=C/F would be 1-chloro-cis-1-bromo-2-fluoroethene. Neon Merlin 11:59, 29 October 2017 (UTC)[reply]

I think it is hard to answer this sort of "why didn't they do it like that?" question. The rules used have some arbitrary components. At this point though, practically, suppose someone introduces your rule. What does it mean? Well, sometimes you can use it, sometimes you might use it, often you would encounter things labelled with E/Z notation. So it means we have to learn your scheme and how to apply it to compounds like [1] with four different kinds of atoms attached to the double-bonded carbons (which is actually not recommended according to our cis-trans article) and whether the "cis" applies to the thing directly after it or the two things in the "di" or ... whatever. And then we also have to be ready to understand E-Z notation. Which amounts to more trouble to learn, more entries in the tables of synonyms in a PubChem entry (exponentially more, since this permutes with every other arbitrary decision we make between naming systems), more errors. I think many people would not be pleased to encounter this kind of creativity in their chemical closets. Wnt (talk) 15:52, 29 October 2017 (UTC)[reply]

This explains situations where cis-trans is different from Z-E. Cis-trans is a subset of Z-E notation, such that all cis are Z and all trans are E, but the inverse is not true. The Z-E notation, it should be noted, is formal IUPAC convention, where as cis-trans is more informal (i.e. the difference between "ethanoic acid" and "acetic acid") As noted, there is no meaningful way to answer a question "why didn't they". Because they didn't. This is the system. --Jayron 32 12:18, 30 October 2017 (UTC)[reply]

Your first statement is not true either. Trans-2,bromobut-2-ene is (Z)-2,bromobut-2-ene, because the groups with the higher priority on each end of the double bond are CH₃ and Br respectively. So the E-Z convention compares the CH₃ and the Br, while the cis-trans convention compares both CH₃ groups, producing opposite results. Double sharp (talk) 13:04, 30 October 2017 (UTC)[reply]

Even more reason why there are two systems. Thank you, Double Sharp! Well answered! --Jayron 32 13:23, 30 October 2017 (UTC)[reply]

Thank you!

As for the OP's original question: in principle, you could indeed build a consistent system this way. However, (1) it's not used by anyone, and (2) it seems to be more problematic to decode because cis and trans only encode relative stereochemistry, whereas E and Z use an absolute frame of reference from the priority rules, as can be seen from my previous example. But you can certainly be the judge: try decoding the molecule name (4E,6Z)-1,1,7-trichloro-4,6-dimethyl-1,4,6-nonatriene (an example I got from the wonderful resource Master Organic Chemistry), and then try writing its name under your proposal. I think you'll find that the need to constantly shift your frame of reference in the relative nomenclature and nest the "cis" and "trans" in such a case is not worth the backward compatibility for the simple cases. Double sharp (talk) 14:51, 30 October 2017 (UTC)[reply]

J. E. Hogarth

There is no direct reference to J. E. Hogarth in Wikipedia, or the WEB, except for indirect links that cite his published work as for example in Stephen Hawkings dissertation. Why is this?

Is he notable in the Wikipedia sense? If he is, then he will have been written about elsewhere (try libraries if not on the web), and if not then he doesn't merit an article here. Dbfirs 16:38, 29 October 2017 (UTC)[reply]

I think maybe not? Here [2] is all the records for JE Hogarth on Google Scholar. Many of those are clearly not a guy who Hawking would be citing in his dissertation. His most notable work is published in Proc. Roy. Soc. A in 1962 (PDF here [3], it's about the arrow of time, among other things, and it seems the sort of cosmological thing that Hawking would have been interested in. It has attracted only 130 citations since then. Now, bibliometrics alone cannot establish or rule out notability on their own, but honestly, that's just not a very big impact (e.g. I have a paper with around that many citations published in 2011, and I'm a total nobody as far as WP notability is concerned, even if a few famous folks have cited my work).

Other than that, I can see a record of his dissertation and abstract [4], and that he was an editor for a few years [5] for the Ontario Association for Mathematics Education, and a member of the Canadian Mathematical congress [6] SemanticMantis (talk) 18:47, 29 October 2017 (UTC)[reply]

If you search Google Books rather than Google Scholar, you will find at least one that describes his work rather extensively, so I think he meets the notability criteria. The real problem is that hardly any information about him. He was in the Math Department at Queen's University in Ontario for many years, and has children living in the area, but that's basically all I can find out about him. He doesn't seem to have published anything significant after 1963. Looie496 (talk) 18:53, 29 October 2017 (UTC)[reply]

From what is accessible using Google, the most detailed might be this. Curiously, or ambiguously it states: "Although Hogarth only published his analysis in 1962, it was generally known to many people before that time." I think there is mention of a thesis of him dated 1953, if that is correct I would be curious to know what was the situation precisely between 1953 and 1962. --Askedonty (talk) 19:37, 29 October 2017 (UTC)[reply]

I suppose it could go either way. For this kind of guy, we'd have to specifically apply Wikipedia:Notability_(academics)#Criteria, not just general notability standards. Maybe his "research has had a significant impact in their scholarly discipline", but that seems a little odd given his frankly thin publication and citation counts. Then again, it's quality not quantity that counts, so perhaps the book you mention could be used as an RS to demonstrate significant impact. SemanticMantis (talk) 14:32, 30 October 2017 (UTC)[reply]

(To be fair, in taking a bibliometric approach to notability I would tend to weight individual citations from fifty years ago more heavily than citations from today—there were fewer journals, fewer papers, and fewer footnotes per paper back then; each cite represented a much bigger slice of the total-citation pie.) That said, for questions of Wikipedia "notability", we might wish to invite – or even defer to – the expertise of Wikipedia:WikiProject Physics. TenOfAllTrades(talk) 00:16, 3 November 2017 (UTC)[reply]