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Pseudomonad

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I created Draft:Pseudomonad, but I noticed that Pseudomonad is currently a disambiguation page, so should I rename it to Draft:Pseudomonad (Category theory) or Draft:Pseudo-monad? (Which is better?) By the way, should I also post this question on WT:MICRO?--SilverMatsu (talk) 16:22, 22 January 2026 (UTC)[reply]

I think Draft:Pseudomonad (Category theory) would be the best approach and then update the DAB page for the new entry. Pseudo-monad doesn't seem like a common spelling. If you go this way, then nothing needs to be changed on the microbiology side. --{{u|Mark viking}} {Talk} 19:01, 22 January 2026 (UTC)[reply]
If you're doing parenthetical disambiguation, it should definitely be Pseudomonad (category theory) . --JBL (talk) 20:00, 22 January 2026 (UTC)[reply]
Yes, "pseudomonad (category theory)" is much more clear. Stepwise Continuous Dysfunction (talk) 20:51, 22 January 2026 (UTC)[reply]
Thanks everyone for teaching me about the draft title. Since there is already a DAB page, I will send a request to move the draft without creating a redirect.--SilverMatsu (talk) 02:13, 23 January 2026 (UTC)[reply]
New title:Draft:Pseudomonad (category theory) --SilverMatsu (talk) 02:38, 23 January 2026 (UTC)[reply]

By the way, is there a connection between Pseudomonad and Doctrine (mathematics)?--SilverMatsu (talk) 06:44, 3 February 2026 (UTC)[reply]

A doctrine is a kind of pseudomonad.[1] --{{u|Mark viking}} {Talk} 12:21, 3 February 2026 (UTC)[reply]
Thank you. I added Pseudomonad to the section of See also in Doctrine (mathematics).--SilverMatsu (talk) 08:28, 4 February 2026 (UTC)[reply]

Comparison with Fourier series in Taylor series

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I am not sure the Fourier series is included in Taylor series#Comparison with Fourier series. But is there any relationship between these two series? I prefer to delete this section. Dedhert.Jr (talk) 00:03, 29 January 2026 (UTC)[reply]

The Fourier series is more closely related to the Laurent series (like a Taylor series but also including negative exponents), of which it is merely a change of variables. The Taylor series is the best polynomial approximation to a function defined near a specific point, whereas the Laurent series is the best Laurent polynomial (polynomial including negative exponents) approximation to a function defined near a circle. –jacobolus (t) 00:41, 29 January 2026 (UTC)[reply]
The section should not be kept as is, but is vaguely recalling something useful from approximation theory. Instead of comparing Taylor series with Fourier series, I think the section should be comparing them with Chebyshev approximation, a polynomial approximation technique over a fixed, finite interval with (IIRC) uniformly bounded error (provided the original function is absolutely continuous). E.g. the following sentences should be readily sourceable if you swap out Fourier series for Chebyshev series:

The computation of Taylor series requires the knowledge of the function on an arbitrary small neighbourhood of a point, whereas the computation of the Fourier series requires knowing the function on its whole domain interval. In a certain sense one could say that the Taylor series is "local" and the Fourier series is "global".

(Chebyshev basis projections over are equivalent to Fourier cosine series over under the change of variable , which might explain the confusion here.) Preimage (talk) 12:39, 31 January 2026 (UTC)[reply]
As you say, a Chebyshev series is a type of Fourier series under a change of variables (specifically, a Fourier series for an even function on the periodic interval ⁠⁠). –jacobolus (t) 15:02, 31 January 2026 (UTC)[reply]
@Preimage. I'll see if I can find some sources for writing. Dedhert.Jr (talk) 13:20, 1 February 2026 (UTC)[reply]

Bhāskara II

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This entire article has problematic statements with a lot of unreliable sources added in many sections like The Siddhānta-Śiroma and Mathematics and it is there for a long time Myuoh kaka roi (talk) 19:19, 30 January 2026 (UTC)[reply]

Infobox images for polyhedra

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There has been some dispute about which images should be used in infoboxes on articles about polyhedra. I was under the impression that these should all be from "the green set" (https://commons.wikimedia.org/wiki/Category:Set_of_polyhedra;_green) unless there is a strong reason to prefer another image. Can anyone chime in on this? — LucasBrown 07:34, 2 February 2026 (UTC)[reply]

I don't really have an opinion on that but I have seen some back-and-forth on my watchlist over whether to use bitmap or vector versions of these images. (In general for new images of this sort of thing I prefer vector formats but in these specific instances I'm not convinced that the vector images were improvements or enough of an improvement to make the exercise worthwhile.) —David Eppstein (talk) 07:51, 2 February 2026 (UTC)[reply]
If someone wants a higher resolution, it should also be entirely possible to re-render all of these POV-ray images. –jacobolus (t) 08:37, 2 February 2026 (UTC)[reply]
The pentagonal bipyramid looks like it is being rotated, difficult to perceive the illustration
On the other hand, this bipyramid gives a better perspective. One can think of the bipyramid in general as two pyramids attached base-to-base. Color can be discussed if it is problematic in the case of colorblindness.
I am fine with using any color provided by Wikimedia Commons. However, it is preferable to provide an illustration with a more general perspective of the given polyhedra, and possibly a symmetrical appearance.
This has happened before in some articles. For example, @David Eppstein's illustration for Triaugmented triangular prism has been discussed, generally not recommended because of different color, ought to match the green color with other polyhedral articles, which is traditionally accepted. Another one is Truncated tetrahedron, which replaces the green color from File:Afgeknotte driezijdige piramide.svg. In some cases, I sometimes convert the polyhedral images to green because of better perspective, like Diminished icosahedron and Pentagonal trapezohedron. Dedhert.Jr (talk) 14:54, 2 February 2026 (UTC)[reply]
To me the green-and-rust-and-gray coloring of many of the images looks arbitrary, like they took a side trip through a clown factory. What kind of 3d environment would actually produce those colors? Look at the pentagonal bypyramid you linked above. We have a bluish-green top front face, an olive top right face, a rust face behind it, a gray face at the bottom, and no change of color at all from the back faces. Why? I'd rather have something closer to monochrome than something that looks fake. I'm sure they were produced by a valid 3d model in povray but it's a model that doesn't resemble reality and where the deviations from reality have no mathematical significance. —David Eppstein (talk) 18:23, 2 February 2026 (UTC)[reply]
Someone could certainly also set up different lighting, material properties, camera angles, etc. and re-render all of these images, if they wanted. Maybe it would be worth pinging the various folks involved in their original creation to ask about the choices they made. –jacobolus (t) 19:23, 2 February 2026 (UTC)[reply]
Haha, is a clown factory a factory where clowns work, or a factory that manufactures clowns?
It looks like all of the green set were produced using this code written by User:Cyp in POV-ray. For individual pictures that don't have a great camera angle, the code could just be used again for a new image of the same model.
Making a whole new set of images with tweaked colors is something I could perhaps get behind, but it would probably be a lot of effort re-doing it for all the green set polyhedra. But on that note, maybe it's actually not a good thing for all of the polyhedra to be the same color! For example, for the elongated square gyrobicupola, the image could maybe do a better job of conveying why it's different from the rhombicuboctahedron if the faces were colored similar to how the net is colored in the same infobox.
As much work as it would be, it could be a fun project! MEN KISSING (she/they) T - C - Email me! 03:32, 5 February 2026 (UTC)[reply]
Both images of nets have atrocious choices of colors in my opinion, so we shouldn't use those colors as-is if we can choose anything else. –jacobolus (t) 04:01, 5 February 2026 (UTC)[reply]
Our article Regular polyhedron has list of polyhedra with mixed colors of shades of green, orange, rust, and heather purple. The tetrahedron use dark green and dark brown, with the edges resembles the almost orthogonal projection. Luckily, I have found a better image and it is nowadays exhibit in both articles Regular tetrahedron and Polyhedron. Dedhert.Jr (talk) 04:52, 5 February 2026 (UTC)[reply]
Proposed alternative color scheme for the same image
Current colors
Hmm, yes, those colors aren't so great of a choice.
How about something like this instead? I feel like cool colors would be more fitting for polyhedra in general than warm colors, and I'd like for faces with fewer edges to be lighter (to tell them apart better, and lighter instead of darker so that the truncated cuboctahedron would look less like a soccer ball).
(Now that I look at it smaller, the color contrast between the squares could certainly be improved, but this is more for demonstration of what a new color scheme could be). MEN KISSING (she/they) T - C - Email me! 04:57, 5 February 2026 (UTC)[reply]
@MEN KISSING. Maybe using three different colors. One is for the eight squares arranged horizontally, the squares from an octagonal prism. You can choose two different colors for the triangles and the other squares. The same can be applied to the net of a rhombicuboctahedron. Dedhert.Jr (talk) 05:00, 5 February 2026 (UTC)[reply]
When choosing colors, I would recommend you use a color space which is relevant to human perception. Oklab is a fast-to-compute option, with some nice online implementations (e.g. oklch.com has a convenient UI), but you could also use CIECAM02 or IPT or the like. For this purpose, you should pick colors with roughly comparable and relatively moderate chroma (doesn't have to be identical, but you don't want one color to be much more intense than the others), and varying lightness (because lightness contrast is the most visually salient to humans, so colors of the same lightness tend to blend together even when other attributes differ). You can pick the hues based on personal preference. –jacobolus (t) 20:47, 5 February 2026 (UTC)[reply]
To be precise, your chosen colors here are something like
  •   oklch(0.77 0.11 213),
  •   oklch(0.80 0.09 247),
  •   oklch(0.82 0.09 277),
  •   oklch(0.91 0.07 166).
I would instead recommend using lightnesses which differ by at least 5 (maybe 0.7, 0.75, 0.8, 0.85), and to the extent possible, uniform chroma. We can keep to this general hue range. Maybe along the lines of
  •   oklch(0.70 0.1 200),
  •   oklch(0.75 0.1 260),
  •   oklch(0.80 0.1 230),
  •   oklch(0.85 0.1 170).
–jacobolus (t) 21:06, 5 February 2026 (UTC)[reply]
For reference, the "current colors" (with numbers rounded a bit and kept in gamut, for ease of comparison) are along the lines of:
  •   oklch(0.87 0.28 142),
  •   oklch(0.82 0.17 110),
  •   oklch(0.63 0.25 29),
  •   oklch(0.45 0.30 265).
The display primary colors are much too intense, the purplish blue is too dark, there isn't enough lightness contrast between the olive and yellowish green colors relative to the lightness contrast between the others, the chroma is much too inconsistent, and the hues are essentially arbitrary. –jacobolus (t) 21:25, 5 February 2026 (UTC)[reply]
If we wanted to stick with the (I assume) originally intended green/yellow/red/blue theme, we also could, with something like:
  •   oklch(0.73 0.16 159),
  •   oklch(0.80 0.16 93),
  •   oklch(0.59 0.18 19),
  •   oklch(0.66 0.14 236).
Which could look like this:
Elongated square gyrobicupola
Edit: though it would probably be better to color alternate squares, along the lines of
Elongated square gyrobicupola
–jacobolus (t) 21:46, 5 February 2026 (UTC)[reply]
I agree; if we're going to color the polygons of a net we should choose a coloring that makes sense relative to the symmetries of the folded polyhedron. Your alternating square coloring does this; the other colorings with one equatorial band of squares colored differently from the rest do not. —David Eppstein (talk) 00:54, 6 February 2026 (UTC)[reply]
@MEN KISSING. Why not? You can trace the edges from a three-dimensional graph drawing with the given coordinates, and choose any color that you want for the surface. Dedhert.Jr (talk) 04:56, 5 February 2026 (UTC)[reply]
I'm not sure what your "why not" refers to, general encouragement? Or do you mean why shouldn't all of the polyhedra be green? MEN KISSING (she/they) T - C - Email me! 05:02, 5 February 2026 (UTC)[reply]
Oh sorry. I thought you wanted to draw polyhedra without using POV Ray, or other three-dimensional drawing software thingy. Dedhert.Jr (talk) 05:04, 5 February 2026 (UTC)[reply]
Ahh, gotcha. If I get enough spare time, I could check out POV-Ray and see if I could get some shapes with fancier colors using Cyp's code. MEN KISSING (she/they) T - C - Email me! 05:07, 5 February 2026 (UTC)[reply]
I have successfully installed POV-Ray on my computer and used it to generate images using Cyp's code. However, that code only implements the Platonics, Archimedians, Catalans, prisms, antiprisms, bipyramids, and trapezohedra—it will take me some time to figure out how to implement the numbered Johnson solids, and also how to adjust things like colors, transparency, line widths, and other fanciness. — LucasBrown 17:57, 5 February 2026 (UTC)[reply]
@AndrewKepert has extended @Cyp's code to include the Johnsons: User:AndrewKepert/poly.pov. — LucasBrown 18:44, 5 February 2026 (UTC)[reply]

Negaton RFD

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Back in the middle of the 20th century "negaton" was used in physics for a negative charge (vs "positon" and not equal to "electron", maybe). The term drop out of use for the most part. However it seems like it was picked up for solutions of PDEs related to solitons in the KdV hierarchy. Just in case someone in math wants to rescue this one: Wikipedia:Redirects for discussion/Log/2026 February 4 § Negaton Johnjbarton (talk) 02:32, 5 February 2026 (UTC)[reply]

Three citations needed in Mayer–Vietoris sequence

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For those who are experts in topology, I need assistance for adding three citations for the article Mayer–Vietoris sequence's topics in the following:

  • "...many other important (co)homology theories, especially singular (co)homology, are not computable directly from their definition for nontrivial spaces."
  • "In general, this does not allow (co)homology groups of a space to be completely computed. However, because many important spaces encountered in topology are topological manifolds, simplicial complexes, or CW complexes, which are constructed by piecing together very simple patches, a theorem such as that of Mayer and Vietoris is potentially of broad and deep applicability."
  • "...so in addition to existing in ordinary cohomology theories, it holds in extraordinary cohomology theories (such as topological K-theory and cobordism)."

Regards. Dedhert.Jr (talk) 01:35, 7 February 2026 (UTC)[reply]

One-dimensional symmetry group

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If someone could please add sources to this page I would appreciate it. It's been unsourced for 21 years.4meter4 (talk) 20:54, 7 February 2026 (UTC)[reply]

Maybe merge with frieze group? —David Eppstein (talk) 21:09, 7 February 2026 (UTC)[reply]

Recent edits to Normal distribution by Bert Niehaus

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I'm having what I think is turning into a bit of a conflict with @Bert Niehaus. Since that user is an academic in mathematics and since the controversy revolves around the addition of ~bachelor-level material to the article Normal distribution, I though I would ask for third-party input here before going through general-purpose conflict resolution procedures.

In a nutshell: Bert Niehaus insists on adding material to the article which — in my opinion — isn't improving it. This started with a batch of objectively clumsy edits, which I reverted. The reason why I'm saying these edits were "objectively clumsy" is that they created a duplicated section, contained grammatical errors, were unsourced and could legitimately be called "OR" (although I dislike the term). I reached to Bert Niehaus on their talk page to explain why I reverted their edits.

This started a lengthy discussion, both on Bert Niehaus' talk page and on the article talk page. Throughout this discussion, I had the impression of repeating the same thing over and over again, namely:

Wikipedia is a not a textbook; in an article such as "Normal distribution", we should simply give the power series expansion of the CDF of the normal distribution with a reference to a source where it is derived, rather than explain in detail how it is derived on the page. We can mention that it is readily obtained by integrating the power series expansion of the PDF term by term, but there is no need to explain in detail why that can be done.

I stand behind that opinion, especially since in my view a detailed argument would only be helpful to a very small number of readers (before having taken a course in complex analysis, one cannot really understand it; and after having taken such a course, it becomes somewhat trivial; so basically the details of the derivation are only going to be useful to a few math students — when the article "Normal distribution" should be aimed at a very large audience).

During this discussion, Bert Niehaus kept making batches of edits to the article — presumably in good-faith, but without really taking into account what I was saying (or perhaps not understand it, since in their latest edits they added a reference to support a notion [uniform convergence] rather than a statement). Also, I'm presuming good-faith here, but having in mind that I was asking Bert Niehaus to slow down, some of these edits did feel like they could have been trolling (e.g, this edit to the lead).

The current situation on my side is this: I am done talking with that use and do not wish to invest any more time in this. But I also do not think their edits are improving the article. So I am not sure what to do: should I just revert everything mechanically until that user gives up? Or ask for third-party input for edit warring?

14:47, 15 February 2026 (UTC) Malparti (talk) 14:47, 15 February 2026 (UTC)[reply]

I can't offer much advice on the best course of action for how you should proceed. But many probability wikipages, especially those for particular distributions, are pretty unwieldy and messy. So it's good to remove material if it is not well-attested to in standard sources like well-recognized probability and statistics textbooks, of which there are many. Anything like original research or original computations should absolutely be removed. Since these pages are so messy, even if the material were to appear somewhere in some random research paper, it is probably good to remove it.
Personally I'm not aware of any reason for interest in the Taylor series for the pdf or cdf of the normal distribution. And taking a quick look through this material, it doesn't seem like any (standard) sources for this have been put forward. So, unless I missed a reference, that means that all this material should be removed. And, regardless, any derivation or calculation details should certainly be removed. Gumshoe2 (talk) 16:10, 15 February 2026 (UTC)[reply]
The formula for the distribution seems potentially useful, but also like an easy exercise. Given the Taylor series for , it's not hard to find the formula for , and from there to get the series for . A section about the Taylor series probably would help statisticians and other such readers, but the benefit would be marginal, and it could make the article more difficult for lay readers. The BooleanTalk 21:04, 15 February 2026 (UTC)[reply]