User talk:Double sharp

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"You have new messages" was designed for a purpose: letting people know you have replied to them. I may not watch your talk page and I will likely unintentionally IGNORE your reply if you do not ping me in it, use Template:Talkback, or copy it to my page, as I will not be aware that you replied! I also prefer to keep the conversation in one place and not split across multiple pages. Thank you.

The following users watch my talk page (feel free to add yourself to this list if you do so too).

FAC chat[edit]

Can you take care of the remaining problems? Those "unreferenced para" claims that I did not object are especially important. Not sure if I'll be able to make further edits today.--R8R (talk) 14:27, 18 February 2017 (UTC)

I think there's a good source for the "In space" paragraphs somewhere in my talk page archives (I think I might have mentioned it while talking to you about nucleosynthesis). I should be able to find that one very quickly; the others should come a little bit later. Double sharp (talk) 14:45, 18 February 2017 (UTC)

Nergaal wants a talk about "double magic" numbers. One question that hasn't been clear to me anyway: how does this double magicity affect lead-208? It's the heaviest known stable nuclide, but still theoretically unstable and still there is a heavier practically stable one.--R8R (talk) 10:54, 19 February 2017 (UTC)

209Bi, I imagine, doesn't want to undergo alpha decay because that would breach the filled subshell as well as the single proton outside it; it is still single magic, after all. Double magicity is not a guarantee of stability: look at 78Ni and 132Sn, for example. All the shell effects in the world will not save you from having such a terribly mismatched proton–neutron ratio! ^_^ It does do a lot for its abundance; not only is there the cycling factor to deal with if anything does manage to pass Pb, but making 209Bi in the first place is not so likely because the double-magicity means that 208Pb has a very low cross-section for capturing another nucleon (and for this reason it has been suggested to use 208Pb as a neutron moderator and reflector). Double sharp (talk) 11:19, 19 February 2017 (UTC)
Okay, I got it why 209Bi is stable. Still, does double magicity do much in lead-208 given that lead-207 is stable as well? I checked and all even-numbered elements with Z>=70 have an even-even isotope as their most stable one; not just lead.--R8R (talk) 11:36, 19 February 2017 (UTC)
I don't think it does much except make 208Pb significantly more common, since 207Pb is not unhappy to capture a neutron while 208Pb is (if I may personify the nuclides)! The footnotes give 207Pb a greater predicted half-life than 208Pb, after all, although both of them make Brahma seem like a mayfly. ^_^ I'm not sure what you mean by the "most stable" isotope if almost all the natural ones really are stable; if you mean the most common one, then Pt is an exception. Double sharp (talk) 14:46, 19 February 2017 (UTC)
Oh, right. Wanted to say "all even-numbered elements with Z>=70 have an even-even isotope as their heaviest stable one." :)
Thank you for the reply.--R8R (talk) 15:20, 19 February 2017 (UTC)
@R8R Gtrs: I realise I never quite explained that feature of the nuclides chart: the line of stable nuclides does tend to look like a connected "continental shelf", with some double-beta-decaying islands off it (like 180W on the proton-rich end and 150Nd on the neutron-rich end). As for why these islands are exclusively even-even: if you plot binding energy against proton number for some consecutive isobars for A odd, you will alternate between even-odd and odd-even nuclei, so pairing effects will be similar for each, and that contribution can mostly be ignored as rather constant. So, bearing in mind the narrow range of beta stability, your graph should look like an upward-opening parabola with the minimum at the most stable nuclide of that mass number: for A = 127, you'd get it at 127I, and for A = 105, you'd get it at 105Pd. But the situation is slightly different for A even; then you alternate between even-even and odd-odd nuclei, so you alternate between having a double dose of pairing effects (which help stability) and having none at all (which clearly doesn't help). So you are going to have two parabolae, one lower down (for even-even nuclides) and one higher up (for odd-odd nuclides). This creates those islands; 204Hg cannot beta decay to 204Tl, even though both 203Tl and 205Tl are stable, because the distance between the parabolae is such that 204Tl is much higher on the graph than 204Hg, which is only a tiny bit higher than 204Pb. So the only decay open to it would be double beta decay, with the minuscule amount of energy released, and so it is no wonder that nobody has actually seen 204Hg decay.
Of course, this is the "normal" behaviour that things settle down to around the third period, when you first get these kinds of islands. Before that, the parabolae are very narrow, because there are very few protons and neutrons and having an imbalance is rapidly fatal to the newborn nucleus. For A = 2, there is only one parabola, and a rather degenerate one at that, because apart from deuterium no nuclide with A = 2 is even bound at all. Deuterium is very weakly bound – you cannot excite it without having it fall apart – but it is bound, so it is by default the nuclide with A = 2 of minimum binding energy, and much the same thing happens with A = 6, 10, 14. Pairing does progressively have more and more of an impact here: 6He and 6Be are both mayflies (actually the latter is not even bound), but 10Be is pretty stable, and 14C is even more so, until at last at 18O we get a truly stable nuclide. Furthermore, 4He is so tightly bound that A = 5 and A = 8 both have a big problem with staying stable, as they fall apart too readily. The most instructive (and perhaps saddest, if you like personifying the nuclides) situation is with A = 8; again you get the two parabolae (quite narrow ones), and of course 8Be is at the bottom, being quite tightly bound for its size. Alas, its half-life is a fleeting 70 attoseconds, because it breaks up immediately into two 4He nuclei which are together just a tiny bit more bound, a cautionary tale that demonstrates that you can only use these parabolae to examine beta decay, and not alpha decay or spontaneous fission.
Well, this was fun to write, although I'm not sure how much of it will be of use. If you need clarification for anything, or if you need me to go look for some of the sources I learned this stuff from, please, ask away. ^_^ Double sharp (talk) 14:10, 17 March 2017 (UTC)
P.S. Someone made an illustration of the parabolae for even A! Double sharp (talk) 14:22, 17 March 2017 (UTC)
Thank you. I got it as I looked at the picture prior to reading your reply. :)
Yeah, I'm sort of uneasy about that now. Can't think of an application for this story off the top of my head.--R8R (talk) 22:10, 18 March 2017 (UTC)
I can think of one article it does belong in: double beta decay. ^_^ Other than that, I agree, although some of it might belong in some of the nuclear physics articles. Even and odd atomic nuclei hints at this, but doesn't go all the way to the parabolae and the edge cases like I talked about here. Double sharp (talk) 04:04, 19 March 2017 (UTC)

And another one. N also added this comment: "I think fundamentally, it should be pointed out more explicitly somewhere that any heavier elements than Pb/Bi that existed when the solar system formed have decayed into Pb/Bi, except for the relatively small amounts of U and Th. it's a bit unclear right now to non-experts." I definitely think we should follow but haven't thought of a way to do so. Could you help me?--R8R (talk) 11:08, 19 February 2017 (UTC)

I'd start by noting that all elements outside H–Mo, Ru–Nd, Sm–Bi, Th, and U have half-lives much shorter than the age of the universe, which easily accounts for their absence. The half-life of Th is about the same as the age of the universe, so there is no problem in explaining why it's still there, and U has only had time for three half-lives, so we should still have one-eighth of the original amount. (Of course I know they weren't created in the Big Bang, but the approximation is okay since the numbers are so large.) Their daughters are the elements in the gap of stability in between (Po–Ac and Pa in the main decay chains, with traces of Tc, Pm, Np, and Pu), which now only exist on the basis of secular equilibria with their parents. Double sharp (talk) 11:19, 19 February 2017 (UTC)
This is an okay story for a general explanation, but as is it doesn't seem very suitable for lead as we have to keep the story focused on lead. Besides, we need to incorporate that into the current text somehow. Could you give it a try?--R8R (talk) 11:36, 19 February 2017 (UTC)
How about something like "Lead and bismuth are the heaviest practically stable elements. Thus, any heavier elements that were produced in the progenitor supernova of the Solar System have long since decayed to lead and bismuth, with the exceptions of thorium and uranium: alone among the heavier elements, they have half-lives comparable to the age of the universe and have thus not had enough time to decay away completely. As they continue to decay, the amount of lead in the universe is increasing, albeit very slowly." That could actually tie in well with the first paragraph of "In space", come to think of it. Double sharp (talk) 14:08, 19 February 2017 (UTC)
Thank you. You helped me realize I don't want this talk in Isotopes at all. We'll get to discuss this in In space.--R8R (talk) 14:36, 19 February 2017 (UTC)

Oh, and thanks for fixing the mass-number issue; it just gets too long. I suppose the real way to say it would be that any mass number not congruent to 1 mod 4 becomes Pb, and any mass number that is congruent to 1 mod 4 becomes Bi, but I think that's too much detail that distracts from the main focus. Double sharp (talk) 14:52, 19 February 2017 (UTC)

Yeah, that's too complicated so I didn't bother.--R8R (talk) 15:20, 19 February 2017 (UTC)

There are yet many points to reply to in the review, and while I could use some help with the load, I would especially appreciate your help with this one: Nergaal wants a talk about alchemy. I'd love you to bring it back into the article, but not limiting the discussion to the European tradition, but also extending it to the Arabian one. See also this.--R8R (talk) 15:06, 22 February 2017 (UTC)

Well, I know almost nothing about this, but I shall go do some research! ^_^ Double sharp (talk) 15:19, 22 February 2017 (UTC)
Great. I'm going not to edit Wiki for a couple of days. I've reacted to many points raised but I hope you help me finish the backlog while I'm away.--R8R (talk) 19:54, 24 February 2017 (UTC)
No problem. I'll continue looking for a few sources about the Arabian alchemical tradition, but if I haven't got something about that written by tomorrow I'll work on the rest of the backlog first! Double sharp (talk) 13:50, 25 February 2017 (UTC)
@R8R Gtrs: I don't find many differences between the Arabian tradition and the Western one in the practice, in part because so much knowledge from the latter came ultimately from the former (there were medieval forgeries of Geber, for example). Pb was certainly known to Geber (although he thought it was a combination of some ideal Hg and ideal S, and that transmutation would involve changing the quantities of each; but that links directly to the idea of the philosopher's stone and turning Pb into Au, and that is so basic that I feel confident in saying that we already have it without opening the Pb article in a new tab ^_-☆). The one distinct thing I can find in Alchemy and chemistry in medieval Islam is that Geber had some numerology of connecting the properties of an element to its name in Arabic, but it feels kind of unconnected to the rest, and some of the citations (e.g. Holmyard) seem to not lead to anything in the list of references(?!). So in general, I don't think it really adds all that much. Double sharp (talk) 14:17, 17 March 2017 (UTC)
I learned from alchemy that there are other alchemies than the European and Arabian ones (which both descend from an Ancient Greek tradition if I got that right), but also Ancient Egypt and India. Given this, I don't think saying that hurts.--R8R (talk) 17:26, 17 March 2017 (UTC)
Yes, yes, of course it doesn't hurt! ^m^ But I just thought that there might not be that much to add, even though we should have it there of course. ^_^ Double sharp (talk) 15:21, 18 March 2017 (UTC)

Feedback from Scerri[edit]

Hi Double sharp; did you get my e-mail? Sandbh (talk) 23:52, 18 February 2017 (UTC)

Yes, I did. I'm going through it and thinking about how best to respond. Double sharp (talk) 04:04, 19 February 2017 (UTC)
Excellent! Sandbh (talk) 05:13, 19 February 2017 (UTC)
Thinking aloud before sending you an actually more definitive version:
Regarding the blocks, I suppose they are to some extent a useful fiction, but then so are a lot of things. I have a nice quote about this: "bonding is not an observable quantity; only bonding distancies and electron density are amenable to observation" (J. F. Lehmann, G. J. Schrobilgen, K. O. Christe, A. Kornath, R. J. Suotamo, Inorg. Chem., 2004, 43, 6905); as a result, even telling us which orbitals are involved in bonding (e.g. all the d-orbital explanations for hypervalence) is mostly of pedagogical value, and obviously a rationalisation of blocks based on that is stacking useful fictions on useful fictions. As p-block elements go, it seems to me that the noble gases are a massive outlier from the rest of the elements in their unwillingness to react, so saying that He fits better in the p-block obscures the fact that its whole group does not exactly fit well in the p-block or any block at all. (If I may speculate within parentheses, maybe the reason people are used to that is because the general unreactivity noble gases gets covered so early in chemistry courses!)
The next three are fine, and maybe we should note that even as group 3 gets ripped from the rest of the d-block, the elements in it are at least next to each other in the d-block, while He is not near any of the s-block elements.
Given how we are stacking useful fictions on useful fictions in creating the blocks, there surely cannot be a decisive argument; we can, at best, assign the blocks to create a compromise table that preserves as many advantages as possible, and when push comes to shove, the chemistry ought to win over the useful fictions, as they did with He, no matter how unnerving or unaesthetic the loss of symmetry might be felt to be. (When I actually send the final version this is surely not going to be one long sentence, but I think that is kind of the entire point we were trying to make; maybe I didn't phrase it well enough. Such are the pitfalls of having thought about things for too long; one's reasoning becomes crystal clear to oneself and to no others! ^_-☆) Double sharp (talk) 02:54, 22 February 2017 (UTC)
This is timely. Your thoughts match my own. I'll probably be skyping Scerri next Wed arvo my time, to discuss the submission =:o so it would be good to get back to him shortly about his feedback. Sandbh (talk) 04:42, 22 February 2017 (UTC)
May I have that definitive version soon? It's Sunday morning here and I'd like to give Scerri some thinking time before I speak with him. Sandbh (talk) 22:08, 25 February 2017 (UTC)
Coincidentally, I was going to give it a last read through and send it today anyway. ^_^ Double sharp (talk) 03:44, 26 February 2017 (UTC)
All right, I've sent it. I've been thinking for way too long on it, so I tried to clarify it several times. Now I'll get back to looking at the Pb FAC and fixing things... Double sharp (talk) 15:43, 26 February 2017 (UTC)


Seaborgium.svg Congratulations, it's a...
...Wikipedia Good Article!! Shearonink (talk) 08:34, 20 February 2017 (UTC)
Thank you! Double sharp (talk) 08:51, 20 February 2017 (UTC)
Congrats! And, to speak of the current problems, hopefully this will free you up for some FAC replies.--R8R (talk) 15:39, 20 February 2017 (UTC)
Yeah, it probably would; the hilarious problem with Sg is that I wrote it so many months ago (August 2016?!) that I forgot most of it and link rot happened in the meantime. Thankfully there wasn't much to change. ^_^ Hopefully you don't have to wait so long for Db! Double sharp (talk) 15:43, 20 February 2017 (UTC)

Your GA nomination of Seaborgium[edit]

The article Seaborgium you nominated as a good article has passed Symbol support vote.svg; see Talk:Seaborgium for comments about the article. Well done! If the article has not already been on the main page as an "In the news" or "Did you know" item, you can nominate it to appear in Did you know. Message delivered by Legobot, on behalf of Shearonink -- Shearonink (talk) 08:41, 20 February 2017 (UTC)

March 2017 WikiCup newsletter[edit]

And so ends the first round of the competition, with 4 points required to qualify for round 2. It would have been 5 points, but when a late entrant was permitted to join the contest in February, a promise was made that his inclusion would not result in the exclusion of any other competitor. To achieve this, the six entrants that had the lowest positive score of 4 points have been added to the 64 people who otherwise would have qualified. As a result, some of the groups have nine contestants rather than eight. Our top four scorers in round 1 were:

  • Scotland Cas Liber, last year's winner, led the field with two featured articles on birds and a total score of 674.
  • European Union Iry-Hor, a WikiCup newcomer, came next with a featured article, a good article and a tally of 282 bonus points for a score of 517. All these points came from the article Nyuserre Ini, an Ancient Egyptian pharaoh,
  • Japan 1989, another WikiCup newcomer, was in joint third place at 240. 1989 has claimed points for two featured lists and one good article relating to anime and comedy series, all of which were awarded bonus points.
  • South Australia Peacemaker67 shared third place with five good articles and thirteen good article reviews, mostly on naval vessels. He is also new to the competition.

The largest number of DYKs have been submitted by Vivvt and The C of E, who each claimed for seven, and MBlaze Lightning achieved eight articles at ITN. Carbrera and Peacemaker67 each claimed for five GAs and Krishna Chaitanya Velaga was well out in front for GARs, having reviewed 32. No featured pictures, featured topics or good topics yet, but we have achieved three featured articles and a splendid total of fifty good articles.

So, on to the second round. Remember that any content promoted after the end of round 1 but before the start of round 2 can be claimed in round 2. Invitations for collaborative writing efforts or any other discussion of potentially interesting work is always welcome on the WikiCup talk page. Remember, if two or more WikiCup competitors have done significant work on an article, all can claim points equally.

If you are concerned that your nomination—whether it is a good article candidate, a featured process, or anything else—will not receive the necessary reviews, please list it on Wikipedia:WikiCup/Reviews. If you want to help out with the WikiCup, please do your bit to help keep down the review backlogs! Questions are welcome on Wikipedia talk:WikiCup, and the judges are reachable on their talk pages or by email. Good luck! If you wish to start or stop receiving this newsletter, please feel free to add or remove yourself from Wikipedia:WikiCup/Newsletter/Send. Godot13, Sturmvogel 66 and Cwmhiraeth 13:52, 1 March 2017 (UTC)


Hello again. You helped me translate several film entries from the French wikipedia in the past (e.g. The Angel). Would it be possible for you to please kindly translate these two short articles from the French wiki? If that would be possible, could you please also upload here these films' posters? Many thanks!-- (talk) 16:09, 14 March 2017 (UTC)

Sure, no problem. It should be done by this weekend, I think. Double sharp (talk) 03:06, 15 March 2017 (UTC)
Many thanks!-- (talk) 10:30, 15 March 2017 (UTC)
First one is up: Reconstitution (1970 film). As always, if I messed anything up, please do not hesitate to correct it. I haven't put in the sources yet. The next one will come tomorrow, I think. Double sharp (talk) 15:50, 19 March 2017 (UTC)
Excellent! Please also do not forget about the posters. I will work on enlarging it now.-- (talk) 15:52, 19 March 2017 (UTC)
The first is at File:Reconstitution film poster.jpg. I shall upload the other one when I translate that article – otherwise it'll get deleted without an article using it. ^_^ Double sharp (talk) 15:54, 19 March 2017 (UTC)
Thank you so very much once again for all this work!-- (talk) 17:05, 19 March 2017 (UTC)
Thank you too for improving Wikipedia's coverage of Greek films! ^_^ Double sharp (talk) 02:24, 20 March 2017 (UTC)
Argh, I've been rather short on time today, so you might have to wait a day longer. I wonder though: is it really okay that the sources for Reconstitution are listed in French and Greek? They might be a little more difficult to find for English speakers without a translation (or in the case of Greek, a transliteration). Double sharp (talk) 16:04, 20 March 2017 (UTC)
Thanks for the kind words earlier. I have no problem with waiting another day, please take your time... As for listing sources in languages other than English with no translation given, do you know if there is an official Wiki policy? In books, at least, this stays the norm.-- (talk) 16:06, 20 March 2017 (UTC)
I am not certain, but for music articles (an area I am more active in) it does seem to be the case on Wikipedia that an English translation is always given (e.g. Pyotr Ilyich Tchaikovsky and The Five, in which the Russian is not even given in Cyrillic, but in transliteration). Double sharp (talk) 16:14, 20 March 2017 (UTC)
In that case, I will insert translations in brackets.-- (talk) 16:16, 20 March 2017 (UTC)
OK, I checked WP:HOWCITE: yes, one of the items listed as typically included for WP is "translated title of the book in square brackets after the title if not in English". Double sharp (talk) 16:17, 20 March 2017 (UTC)
Oh, edit conflict. Thank you! Double sharp (talk) 16:17, 20 March 2017 (UTC)
You're most welcome.-- (talk) 16:23, 20 March 2017 (UTC)
The other one is ready: Days of '36. The poster will be uploaded in a moment. Double sharp (talk) 08:43, 22 March 2017 (UTC)
...and Yes check.svg Done Double sharp (talk) 08:46, 22 March 2017 (UTC)
Wonderful! Will start enlarging it soon...-- (talk) 09:44, 22 March 2017 (UTC)
Oh, one last thing: Can you please make sure all foreign-language Wiki articles about this film will appear on the left? Thanks.-- (talk) 10:29, 22 March 2017 (UTC)
Yes check.svg Done Double sharp (talk) 11:28, 22 March 2017 (UTC)
Many thanks once again!-- (talk) 11:30, 22 March 2017 (UTC)
You're welcome! Double sharp (talk) 11:32, 22 March 2017 (UTC)
By the way, I have four submitted drafts waiting for approval. Once these (hopefully) go through (two in fact already have), would you be able to please kindly upload here their theatrical release posters, available at their IMDb pages? Thanks.-- (talk) 19:08, 22 March 2017 (UTC)
The last two articles are now up, so, when you get the chance, I would highly appreciate it if you could upload the aforementioned posters. Thanks again!-- (talk) 18:51, 23 March 2017 (UTC)
Hi. Did you see my latest messages?-- (talk) 10:09, 24 March 2017 (UTC)
Yes, I did. I've just been a little bit busy IRL, so my WP time for the previous two days has mostly been focused on the chemistry-related replies I left outstanding for a while. ^_^ Double sharp (talk) 10:34, 24 March 2017 (UTC)
That's perfectly fine. Just wanted to know that you have no objections to doing so.-- (talk) 10:53, 24 March 2017 (UTC)
Okay, I've uploaded all four and put them in their respective articles. Double sharp (talk) 13:54, 25 March 2017 (UTC)
Many thanks! And, now, for the time being, I am done...-- (talk) 13:57, 25 March 2017 (UTC)
No problem! If you need anything in the future, of course, my talk page is always open. ^_^ Double sharp (talk) 14:04, 25 March 2017 (UTC)