Talk:Wigner distribution

Wigner function vs. Wigner distribution

Hi, there's confusion at least on my part about Wigner functions and Wigner distributions. Earlier I was focusing on Wigner function disambigution page, which was:

Wigner function may refer to:

• Wigner quasiprobability distribution, a quasiprobability distribution used in quantum physics
• Wigner D-matrix, an irreducible representation of the rotation group SO(3)

==See also==

• Wigner distribution (disambiguation)
• Breit–Wigner distribution (disambiguation)

{{disambiguation}}

Although this Wigner distribution page was linked I was not properly aware of it. This page was:

Wigner distribution may refer to:

• Wigner semicircle distribution, a probability function used in mathematics
• Wigner quasiprobability distribution, a quasiprobability distribution used in quantum physics
• Wigner distribution function in signal processing
• Modified Wigner distribution function

==See also==

• Breit–Wigner distribution (disambiguation)
• Wigner function (disambiguation)

{{disambiguation}}

For reasons I explained at Talk:Wigner function I redirected Wigner function to Wigner quasiprobability distribution (call that "W q d"). I have just undone the redirect in order to discuss here. I was perhaps incorrectly guessing that usages of Wigner function or Wigner Function in 8 or 9 articles (see the Talk page) were intended to go to Wigner quasiprobability distribution. And per explanation I added a hatnote at Wigner quasiprobability distribution in (and i mistakenly deleted another hatnote) this edit, which was since reverted by this edit by Cuzkatzimhut. Then I see that this current "Wigner distribution" page was edited to drop the last "See also" which no longer made sense (because it redirected to "W q d", already an option given).

Hey now I wonder, can the two terms "Wigner function" and "Wigner distribution" be covered in one combined dab page (merging the othBer one to here, so this page would start "'Wigner distribution' or 'Wigner function' may refer to..." and would have "Wigner D-matrix" as a 5th meaning. Would that make sense?

And, now I am very unsure whether the 8 or 9 inbound links to the dab page, which I list at Talk:Wigner function, can correctly be edited to point to "W q d" or not. (My redirect was effectively implementing those changes; i have effectively undone them now though.)

I must say I have very little understanding of these topic areas; I am just trying to improve disambiguation, including by refining "dablinks" to dab pages that should link to a specific article instead. Help! --doncram 23:50, 22 August 2015 (UTC)

Hi, it is a royal mess, but i am glad you undertook to fix it... If you got the gumption, then, yes your "I wonder" merge-of-dabs proposal makes plenty of sense , but it takes too much work.

Indeed, as you say on the other dab page, correctly, "Also, the Wigner D-matrix article does not mention "Wigner function" much less that it is a synonym. Superficially, it seems to me that referring to a Wigner D-matrix as a Wigner function is technically wrong; the first is literally a square matrix, not a function."

Also, 9 times out of 10, "Wigner function" is the Wigner quasiprobability distribution (*) linked. However, information scientists have appropriated the expanded term wigner distribution function (#) to mean their, time-frequency variant of the above primary (*), sometimes also called Wigner-Ville distribution and then branch out into generalizations, etc... But the original physics (*) and information science (#) streams are "joined at the hip". (They do not belong to the same article, however, by din't of huge cultural gaps and practices.) The rule of thumb is that regiments of the function x and p signify (*), while t and f signify (#). More significantly, foreign articles /equivalents to each of the above link to different, often wrong quasi-equivalents, by dint of this ambiguity---I see that by now they are largely correct.

So most of the distributions or functions you mentioned are indeed (*), but a small splinter are part of the info science stream and the rest are sloppy expressions or misunderstandings, nicely disambiguated here and at the mergable page... Your efforts are greatly appreciated! Cuzkatzimhut (talk) 12:07, 23 August 2015 (UTC)

Wow, thanks, your comments are very helpful. You give me confidence to make the following changes, though I am hoping you will please review them:

• I re-redirected the Wigner function disambiguation page to here, the "Wigner distribution and Wigner function" disambiguation page.
• I revised this page by this diff with clarifying (I hope) notes copied/adapted from your wordings above, and putting Wigner D-function in only as a 2nd "see also".
• I revised the Wigner distribution function page by this diff to insert a very-much-needed topic sentence, IMO and to replace ambiguous "Cf."
• I revised the Modified Wigner distribution function page to give a hatnote notice about abbreviations being different there, but mainly to insert a topic sentence and to remove confusing appearance that the article was about the Wigner distribution function!
• no change made at Wigner quasiprobability distribution, which remains with hatnote suggesting "see Wigner distribution (disambiguation)"

Given what you've said and my readings of the ledes plus a little bit more of the articles, I am pretty sure these are mostly improvements. I would be very grateful if you would review and make any big changes needed or even very tiny wording improvements, please.

By the way, with all this consideration applied, if I get to re-consider the 8 changes at the other Talk page, I then might or might not earn a 8 lousy points in what is a monthly disambiguation-fixing competition, the Monthly DAB Challenge of the wp:DPL project. I have never ever gotten nearly as far as I am now, but it requires thousands of points to win...i'm currently atop the leaderboard, but others are moving faster. :( (Oh yeah, I am supposed to "remember, it is more important to disambiguate correctly than to disambiguate quickly"...whatever. :) )

Thanks so much, --doncram 02:07, 24 August 2015 (UTC)

Yes, thanks, superficially it all looks fine. The foreign language pages' linkages appear unaffected and the WDF/WD stunt looks sensible, provided the community using that page won't get confused... and come to this disambiguation page!Cuzkatzimhut (talk) 10:54, 24 August 2015 (UTC)

Wow, thanks again, i didn't pick up on your mentioning other language linkages before, and am glad you've reviewed them. Now I see that they could be very important in this topic area, where scientists may well be more fluent in other languages and want to go back and forth between different wikipedias' coverage, in their reading and/or potential editing. I just had to fix my User Preferences (under "Beta Features" to turn off "Compact language links") in order to see any language links at all!

Next i want to review the inbound links (dablinks, actually), which we were saying would usually be fixed by converting them to link more specifically to Wigner quasiprobability distribution ("Q p d").

Cuzkatzimhut have you used the DabSolver tool before? It's easy to use to fix a link to a dab page, by clicking on the highlighted ambiguous term and then selecting, from a drop-down menu, the correct choice on the relevant dab page. To save the page requires two steps: at bottom of page the "Save" button cannot be selected. Select "Show changes" instead to get to another page, where you could make other edits too, and go down to bottom to select "Save" which works this time.

I set up DabSolver links below. In some of them there are multiple usages of "Wigner function" that all need to be fixed. After viewing all the usages, with my extremely shallow understanding, I think but am not sure they should all be converted to link to "Q p d", easily done by selection from drop-down menu. In at least two articles the usage is "Wigner function time evolution" which starts to sound like another choice should be made, but I think they mean "Q p d" there too. --doncram 17:34, 24 August 2015 (UTC)

Tool applications set up:

• Trying: "Dab Fix List" tool applied to "Wigner distribution" dab

Ah that worked. It shows all inbound links from mainspace articles only, including via redirects. NOT LIVE, updates daily. Crossed out items have been edited (maybe fixed, maybe not) since last update. "FIX" for any item brings up DabSolver in a NEW PAGE which can be closed when done.

• Applications of DabSolver tool set up manually to review the inbound links to "Disambiguation function": :::::With inbound links found by "What links here", live. Replaces current page, does not generate new page, so one wants to return to here by hitting "back" one or two times in one's browser. When I write this there are only 5 remaining from mainspace (and there are some non-mainspace ones) to fix:

• Squeezed_coherent_state (switch the one usage to "Q p d" looks good to me)
• Quantum tomography (switch all four usages to "Q p d" looks right to me. One usage is "Wigner function time evolution" though.)
• Phase space formulation] (switch all three usages to "Q p d" looks good to me)
• Koopman–von_Neumann_classical_mechanics‎ (switch to "Q p d" looks good to me)
• Segal–Bargmann_space (switch to "Q p d" looks good to me)
• and one maybe could do a favor and even fix disambiguation at a few user pages?

• User:PieCrate/Discrete_Finite_Phase_Space (switch to "Q p d" looks good to me)
• User:Zeroimpl (switch to "Q p d" looks good to me)

Cuzkatzimhut, could you possibly please make the changes in DabSolver or advise me that I can use "Q p d" for all?

--doncram 17:01, 24 August 2015 (UTC)

Sorry, I was busy. yes, all "Q p d" proposed usages appear good! Go ahead. No, have never used DabSolver. I do editing in quick, scatterbrained spurts, so would rather not take global responsibilities of this type... Thanks. Cuzkatzimhut (talk) 18:31, 24 August 2015 (UTC) Aw, OK, i suppose i did the whole dab list... Cuzkatzimhut (talk) 22:12, 24 August 2015 (UTC)

Thanks for reviewing and for doing the switches! Easily done when the DabSolver is set up, right? Responsibility disavowal notwithstanding, pretty soon you may be listed on the dab challenge leaderboard for this month, you just need 2 more disambiguations!  :) Thanks, really for your help. I think together we made this area better for readers to navigate. sincerely, --doncram 12:50, 25 August 2015 (UTC)