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April 6

What's wrong with the “uno”?

Uno (unit) redirects to Parts-per notation#Uno (proposed dimensionless unit), a short paragraph, which cites that “the response to the proposal of the uno "had been almost entirely negative"”. What were the reasons against it? ◅ Sebastian 10:16, 6 April 2023 (UTC)[reply]

Have you read Reference 14 from that page? --Jayron 32 10:48, 6 April 2023 (UTC)[reply]

Unfortunately, the reference doesn't add anything to the quoted statement. Apparently, those responses (i.e. opinions solicited from peers) have not been published and were not discussed in detail. --Wrongfilter (talk) 10:58, 6 April 2023 (UTC)[reply]

Thanks, Wrongfilter. Your first sentence is exactly what i should have replied. But the second sentence goes a bit too far for me. Are we sure that they are not publicly available anywhere? I couldn't find any with a quick internet search, but that's not enough to rule it out. ◅ Sebastian 12:54, 6 April 2023 (UTC)[reply]

Searching a bit further, i found this from the IUPAC Interdivisional Committee on Nomenclature and Symbols (IDCNS):“Recommendation U3: […] [T]the use of the unit <U or uno> in combination with a prefix is to be preferred [over expressions such as ppm, ppb, and ppt].”[1] There are no considerations against this recommendation. ◅ Sebastian 13:48, 6 April 2023 (UTC)[reply]

See, however, Section 4.10 of the Report of the 15th meeting (17–18 April 2003) to the International Committee for Weights and Measures: "Dr Taylor suggested that the uno could be introduced as a special device for use with prefixes only so that, for example, the usage ppm could become μU, but the uno would not be a unit. This met with some objections and it was pointed out that such a change would require the approval of the General Conference."^[2] --Lambiam 19:48, 6 April 2023 (UTC)[reply]

In the old days, in math classes, we referred to 1 as the multiplication "Identity". ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:37, 7 April 2023 (UTC)[reply]

It's more usually called the "multiplicative neutral element" or "multiplicative identity element", because "identity" on its own is already taken up by the concept your link explains ;-). --Stephan Schulz (talk) 22:52, 11 April 2023 (UTC)[reply]