User talk:Rgdboer

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To facilitate current discussion an archive has been established to clear this page for 2017.Rgdboer(talk)02:40, 22 December 2016 (UTC)[reply]

Undoing edits

Hey, there!

I see that you undid all of my edits from last night onProtein combiningwithout entering any information as to why. Please refrain from doing that. Let me know if you have any questions.

Thanks!

--SaletteAndrews(talk)20:47, 13 January 2017 (UTC)[reply]

The article is very controversial, with dietitians versus biochemists. My contributions to the article ceased in January 2017. However, recently two sources forLiebig's law of the minimum#Protein nutritionhave been provided, and these support the biochemists.Rgdboer(talk)03:04, 5 September 2022 (UTC)[reply]

Laurence Clancy

Hello Rgdboer. I was delighted to see you started a new article onLaurence Joseph Clancy!I started an article on the same person in about 2008 but after a few months it was listed for deletion and, despite my best efforts, the listing was successful. You can read the deletion debate atWikipedia:Articles for deletion/Laurence Clancy.This will show the sort of argument people brought to bear to have "my article" deleted in 2008, and the sort of argument we need to be able to combat in 2017.

You may wish to ask an Admin to retrieve my 2008 article in order to see what it said, and what citations were supplied. Either way, I am happy to contribute to your new article to make it as robust as possible so it can withstand any future deletion debate.

I continue to cite Clancy in most of the aerodynamics articles I work on, so I am very glad Wikipedia again has some information about him. Best wishes,Dolphin(t)03:42, 16 January 2017 (UTC)[reply]

PS: I have asked an Admin to send me the text of my 2008 article; see mydiff.Let me know if you want a copy.Dolphin(t)02:41, 18 January 2017 (UTC)[reply]

PPS:User:RHaworthhas restored the 2008 edits to the history ofLaurence Joseph Clancy.Earlier versions can be seen by selecting them in the history of the current article.Dolphin(t)04:04, 19 January 2017 (UTC)[reply]

I was going to be eliminating those subheader titles that you changed, but thanks!

The way that the section inSpacetimewas going, I was going to delete the subheaders, but thanks! I've always appreciated your contributions!Stigmatella aurantiaca(talk)23:13, 24 March 2017 (UTC)[reply]

Liebmann (1905)

You wrote inMöbius_transformation#Lorentz_transformation,that Liebmann (1905) noted the isomorphism between Lorentz group and Möbius group. However, the1905 editionof his "Nichteuklidische Geometrie" does not contain (as far as I can see) any discussion of the Lorentz group (in the1923 editionthere is a little bit). I think a better source isHerglotz (1909),who pointed out that"Lorentz transformations definitely correspond tohyperbolic motionsin $R_{3}$ ",transforming the unit sphere into itself (p. 407). Using Klein's classification of hyperbolic motions, Herglotz separated the one-parameter Lorentz transformations into loxodromic group, hyperbolic group, elliptic group, and parabolic group (p. 408). --D.H(talk)11:30, 28 June 2017 (UTC)[reply]

Thank you for the notes and links on this fascinating topic. Given that special relativity is a branch of linear algebra (with physical content), the alignment of theRiemann spherewith thecelestial sphereaccomplishes the Möbius-Lorentz group correspondence. Liebmann was cited because Coxeter mentioned him, but now it seems Herglotz is more appropriate. These century-old sources show that Penrose was a late-comer to this topic. —Rgdboer(talk)23:22, 28 June 2017 (UTC)[reply]

I've now included a description of the formulas of Fricke & Klein (1897) and Herglotz (1909) inSpherical_wave_transformation#Conformal_group_isomorphic_to_Lorentz_group.Regarding Liebmann (1905), on pp. 52ff. he discussed the relation between hyperbolic motions and "Kreisverwandtschaften" (Möbius transformations), obtaining and extending some results of Fricke & Klein (without citing them). In the third edition of his book from 1923 (on p. 143), Liebmann mentioned the relationship between Lorentz transformations and motions of the hyperbolic plane using Weierstrass coordinates. --D.H(talk)11:59, 20 July 2017 (UTC)[reply]

The following relevant reference has flaws:

Remi Langevin (2015)Integral Geometry from Buffon to Geometers of Today,chapter 18 "Integral geometry of Lorentz spaces", page 147,Société mathématique de France ISBN 978-2-85629-822-0

The misprint in the description of P_z(third line from bottom of page) has

{\mathcal {L}}(x,z)=1

where it should be

{\mathcal {L}}(x,z)=0.

This orthogonality property is given at the outset, but omits to mentionhyperbolic orthogonalityas the non-perpendicular meaning in this case. The use of Möbius name is overly broad, being invoked for SO(1,1) and the termMobused instead ofLorentz groupas is standard. Langevin's effort to sketch the Mobius-Lorentz group isomorphism is a gloss, not a proof.Rgdboer(talk) 01:37, 25 December 2017 (UTC) —Rgdboer(talk)01:46, 25 December 2017 (UTC)[reply]

Unblock

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Accept reason:It looks like collateral damage. I've unblocked you. Let me know if you have further trouble.NinjaRobotPirate(talk)03:33, 1 October 2017 (UTC)[reply]

Thank you. —Rgdboer(talk)02:42, 1 October 2017 (UTC)[reply]

History of logarithms

R,this versionyou wrote has a story similar to the one we just fixed atNapierian logarithm.The ref 13 doesn't appear to support what's said about this. Care to weight in on where to take this?Dicklyon(talk)02:33, 13 May 2018 (UTC)[reply]

Please correct. That text was copied from Logarithm when History of logarithms was begun. November 24, 2015, the Logarithm article was seen to be too long, with much historic material. The namespace "History of logarithm" had a redirect to Logarithm, so text was moved to reduce Logarithm and begin an independent article. The prehistory ofnatural logarithmincludes the story of Napier, but my efforts have been expended onA. A. de SarasaandGregoire de Saint-Vincent.While mathematics resists the notion of paradigm shifts, the invention of logarithms was revolutionary for productivity and setting up calculus. —Rgdboer(talk)21:27, 14 May 2018 (UTC)[reply]

Relational view on functions

I just came here to express my wish/hope that you do not bother my use ofyour ideafor these edits. Besides your unlucky use of a (typoed?) link, I shared D.Lazard's view of the original place not really being an optimal one. I expect that the new place and the reduced content might find grace in the eyes of the lords. It is beyond me to invite you to possibly add contents, according to your ideas (composition as another example?), but at least I want to say thanks for the trigger.Purgy(talk)11:04, 7 September 2018 (UTC)[reply]

You’re welcome Purgy! Thank you for moving the material higher up the article. Editing on an frequently-viewed article is adventurous! But of course,relationis prior tofunction.—Rgdboer(talk)02:19, 8 September 2018 (UTC)[reply]

Kutta condition

Hi Rgdboer. We are under siege atTalk:Kutta condition# "An aircraft with a wing with a smoothly rounded trailing edge would generate little or no lift.".If you are able to comment that would be appreciated. Regards.Dolphin(t)13:21, 7 October 2018 (UTC)[reply]

A figure fromflow separationwas used to comment onlift (force)and use ofpotential flow.—Rgdboer(talk)02:14, 9 October 2018 (UTC)[reply]

Many thanks for your contribution. I have commented on the Talk page.

I’m sure you are aware that potential flow is based on the assumption of zero viscosity, whereas flow separation occurs because of viscosity, so I find mention of both in the same sentence to be challenging.Dolphin(t)12:25, 9 October 2018 (UTC)[reply]

Relevance?

In reading the list of Hotel Fires (List of hotel fires in the United States), I was struck by the abrupt introduction of what appeared to me as an irrelevant detail. I see that you added that detail on 2013 January 18‎ at 18:32, yet I don't see why.

It may be true that Lucius W. Nieman had become editor of a paper, but what does that particular detail have to do with Hotel Fires in general? I could see that that part could be rephrased to give similar info but without reference to Mr Nieman: A local newspaper (The Daily Journal) told the "appalling...

The fact that he had become the editor a few weeks prior to the fire leads to a belief that he was somehow responsible for the article about the fire, yet there is no clear connection nor even a clear indication of when that article was published. The rest of that paragraph, referencing the other newspapers in town doesn't seem to be relevant either.

Could you please readdress that article and see if the details can be either tied in to the topic or removed?

Thanks!WesT(talk)18:00, 31 December 2018 (UTC)[reply]

The contribution has been re-written and moved to its section. The article has grown over six years, and that particular fire was recalled in a 1913 reference detailing other deaths on the Hotel's block. Nieman exploited the tragedy in his newspaper for gain, as noted by Scott Cutlip. In 2013 contributions topublic relationsandhistory of public relationsled to the Cutlip observation. Thank you for calling attention to the Newhall house fire; the accent now is on the "death block" rather than media exploitation. —Rgdboer(talk)00:28, 1 January 2019 (UTC)[reply]

Asking for clarification in an old entry

InSplit-quaternion,when you created it in Feb 2007, there is something like this:

where u* = w - x i and v* = y - z i (complex conjugates of u and v), represents q in the ring of matricies in the sense that multiplication of coquaternions behaves the same way as the matrix multiplication. For example, the determinant of this matrix u u* - v v* = q q*; the appearance of this minus sign where there is a plus in H leads to the alternative name split-quaternion for a coquaternion. Historically coquaternions preceeded Cayley's matrix algebra; coquaternions (along with quaternions and tessarines) evoked the broader linear algebra.

What do you mean by "H", I wonder.

Dụng hộ danh vĩnh viễn dĩ tồn tại(talk)19:47, 2 June 2019 (UTC)[reply]

Convention uses ℍ to designatequaternions,like ℂ forcomplex numbersand ℝ forreal numbers.Will edit to clarify. Thank you for noticing. —Rgdboer(talk)21:52, 2 June 2019 (UTC)[reply]

Use of INTDAB for disambiguation, August 23, 2019

An automated process has detected that when you recently editedMurphy,you added a link pointing to the disambiguation pageAlex Murphy(check to confirm|fix with Dab solver).

(Opt-out instructions.) --DPL bot(talk)07:42, 23 August 2019 (UTC)[reply]

Usually these notifications are deleted once the disambiguation has been made. In this case it can be left to show the bot's failure to comprehend that the Alex Murphy page should be on the Murphy page even when there are several people called Alex Murphy. —Rgdboer(talk)20:53, 23 August 2019 (UTC)[reply]

Standard approach to this situation is described atWP:INTDAB,a Project convention. —Rgdboer(talk)21:48, 28 August 2019 (UTC)[reply]

Conformal symmetry

HelloRgdboer.The purpose of my edit onconformal symmetrythat you just reverted was to start bringing some order to the noodle soup of articles onconformal symmetry,conformal map,conformal geometry,conformal group.There is much duplicated material there, and in my opinion we need one or two articles instead of four. What do you think?Sylvain Ribault(talk)07:41, 9 October 2019 (UTC)[reply]

Noodle soup is a metaphor, hardly applicable. Why contract the Project? A challenge in the topic is finding sources that acknowledge thathyperbolic angleis an invariant of Lorentz transformations. That fact makes conformal physics much more involved than theinversive geometrythat started the subject. In this project Physics and Mathematics are largely merged (not forcompactification), so sources can conflict due to silos in academia. Please refer tosplit-complex numberandlinear fractional transformationfor mathematical understanding. As for the soup, sip slowly from the bowl edge as it’s very hot. —Rgdboer(talk)22:46, 9 October 2019 (UTC)[reply]

Respond to edit on talk page

You undid two of my edits onTemplate: number systemswithout responding to my comments on the talk page. I think it's worth grouping the planar numbers together. Also, where are the dual-complex numbers listed as a hypercomplex system? They aren't listed anywhere. As such, I'm reversing the edit. --Svennik(talk)23:44, 22 October 2019 (UTC)[reply]

This issue stems fromHypercomplex number#Two-dimensional real algebras.The discussion continued atTemplate talk:Number systems.—Rgdboer(talk)00:32, 19 November 2019 (UTC)[reply]

Disambiguation link notification for January 18

An automated process has detected that when you recently editedAllegory (mathematics),you added a link pointing to the disambiguation pageGroup(check to confirm|fix with Dab solver).

(Opt-out instructions.) --DPL bot(talk)10:05, 18 January 2020 (UTC)[reply]

November 2020

Hi Rgdboer! I noticed that you recently marked an edit as minor atMusic and mathematicsthat may not have been. "Minor edit" has a very specific definition on Wikipedia – it refers only to superficial edits that could never be the subject of a dispute, such astypo correctionsor reverting obviousvandalism.Any edit that changes themeaningof an article is not a minor edit, even if it only concerns a single word. Please seeHelp:Minor editfor more information. Thank you.Kj cheetham(talk)18:48, 20 November 2020 (UTC)[reply]

The change was a disambiguation ofmusical performancetomusical phrasing.My impression was thatWP:Dabis a minor edit, but that may be wrong. The article WP:Dab does not indicate either way. Thank you for the notification and caution in marking an edit as minor is in order. —Rgdboer(talk)04:46, 21 November 2020 (UTC)[reply]

It was the edit before that about 53 equal temperament I was thinking of. Happy editing in any case though! -Kj cheetham(talk)09:44, 21 November 2020 (UTC)[reply]

bounded, negative, finite ordinals

A simpler version of the Russell idea you mentioned atOrdinalsand its talk page, that does work adequately with the usual idea of ordinals, is to pre-pend a specified finite number of negative steps before the start point. E.g., begin counting at -17 rather than 0 or 1. This doesn't change the order type of any infinite ordinal, or finite ordinals if the definition of (the notation for) those is modified to mean the interval between the number and 0. The union of all such negative prefixes to the usual ordinals is not allowed, in that it violates well ordering, but particular cases are compatible with the standard language.73.89.25.252(talk)20:19, 3 December 2020 (UTC)[reply]

Hello Somerville, Massachusetts, USA, yes, we clicked atTalk:Scientific notation#Order as a scale, not a number.The consequentdoubly infinitesequence came up on another article. The issue has existed since Russell mentioned inThe Principles of Mathematicsthe counting backward from any position in a progression. Perhaps he forsaw the study of luminosity of Campanus, planets, moon, and sun on the scale of Hipparchus. Your suggestion appeals as an accomodation of that situation in an order of magnitudes. But negative twenty-seventh magnitude for the Sun is at one astronomic unit, so a scale going closer to the sun, would call for another position for the zero. Admitting the doubly infinite is part of scientific notation, regardless of Georg Cantor. Indeed, the doubly infinitegeometric progression10ⁿ,n in Z, sections the positive reals for access. You are invited to become aWP:User.—Rgdboer(talk)02:19, 7 December 2020 (UTC)[reply]

The accomodationist strategy is often used where allowing some kind of extension, but only a finite amount of it, does not qualitatively change things (e.g. field or ring extensions, coverings) but throwing in all the finite adjustments at once gives a different sort of creature that does not belong to thecategoryof interest. Typical use case is where a finiteness condition appears, such as finite dimension, finite ascending or descending chains, well ordering. Or using "almost" to denote a finite number of exceptions.

The problem with allowing the infinite modifications is not that it's wrong or can't exist but that the category of allowed objects would lose nice properties in the name of inclusiveness. Literal "can't have nice things" so that the extension is allowed for its own sake.73.89.25.252(talk)18:01, 7 December 2020 (UTC)[reply]

Indeed, the doubly infinite geometric progression 10^n sections the positive reals for access.The distinction between "ordinal number" (having levels or layers or a hierarchy), and "integer" as in the stuff of arithmetic, seems to be a matter of linguistic custom or historical tradition that is orthogonal to the scientific notation discussion. The problems with OOM as an integer approximation function to the logarithm are practical mathematical concerns. 1) that anything physically meaningful (invariant) for dimensionful quantities has to be a binary relation, i.e., based on a ratio; 2) that the specific binary relation "same OOM" does not reduce to a unary function; 3) that if you do take it to be a function of one variable, it becomes dependent on a choice of rounding scheme, so again non-invariant; 4) if you do fix a rounding scheme anyway, it has to be discontinuous, so that almost identical quantities "have different order of magnitude" if OOM is defined in such a way; 5) that log-scale is unnatural for OOM approximations, we want them to be on the same scale as the input. All this is why (6) cognoscenti use the binary relation and the unary convention hasn't caught on, except maybe for people who only teach (or are forced to learn-and-forget) the stuff rather than use it for real. I tried drafting a re-write of theorder of magnitudearticle and it's quite a pain to start over. Probably easier to do a minor fix onscientific notationfirst.73.89.25.252(talk)06:42, 8 December 2020 (UTC)[reply]

This is being discussed at the Decade talk page in case you are interested.73.89.25.252(talk)01:27, 18 December 2020 (UTC)[reply]

Proposed deletionof2 × 2 real matrices

The article2 × 2 real matriceshas beenproposed for deletionbecause of the following concern:

SeeTalk:2 × 2 real matrices#This article must be deleted

While all constructive contributions to Wikipedia are appreciated, pages may bedeleted for any of several reasons.

You may prevent the proposed deletion by removing the{{proposed deletion/dated}}notice, but please explain why in youredit summaryor onthe article's talk page.

Please consider improving the page to address the issues raised. Removing{{proposed deletion/dated}}will stop theproposed deletion process,but otherdeletion processesexist. In particular, thespeedy deletionprocess can result in deletion without discussion, andarticles for deletionallows discussion to reachconsensusfor deletion.D.Lazard(talk)11:02, 8 February 2021 (UTC)[reply]

Nomination of2 × 2 real matricesfor deletion

A discussion is taking place as to whether the article2 × 2 real matricesis suitable for inclusion in Wikipedia according toWikipedia's policies and guidelinesor whether it should bedeleted.

The article will be discussed atWikipedia:Articles for deletion/2 × 2 real matricesuntil a consensus is reached, and anyone, including you, is welcome to contribute to the discussion. The nomination will explain the policies and guidelines which are of concern. The discussion focuses on high-quality evidence and our policies and guidelines.

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D.Lazard(talk)10:20, 9 February 2021 (UTC)[reply]

The article, slightly edited, is available throughWikibooks:

b:Abstract Algebra/2x2 real matrices

Readers may comment on linear algebra here.Rgdboer(talk) 04:16, 10 October 2021 (UTC)Rgdboer(talk)04:26, 10 October 2021 (UTC)[reply]

Your edit of "transformation semigroup" 03:13, 3 October 2019‎

Hi: I somehow feel that your changes at 03:13, 3 October 2019‎ were adding confusion, if not wrong. You changed the explanation of "transformation" from "function" to "partial function", which seems to be in contradiction to the definition of "transformation semigroup" in the first sentence, which reads:

"a transformation semigroup (or composition semigroup) is a collection of functions from a set to itself that is closed under function composition."

It seems also in contradiction to a paragraph below:

"The set of all transformations of X is a transformation monoid called the full transformation monoid (or semigroup) of X."

where the "full transformation monoid/semigroup" usually means the monoid/semigroup of all functions (e.g., in Howie's book), not partial functions.

Or did I misunderstand your edits?ALife(talk)07:19, 22 February 2021 (UTC)[reply]

SeeTransformation semigroup.The reader was right, thank you. Link toPartial functionnow placed in next sentence. —Rgdboer(talk)03:43, 22 February 2021 (UTC)[reply]

Looks good. Thanks.ALife(talk)07:19, 22 February 2021 (UTC)[reply]

Proposed deletionofAbraham Cornelius Benjamin

The articleAbraham Cornelius Benjaminhas beenproposed for deletionbecause of the following concern:

Not notable byWP:GNGorWP:PROF

While all constructive contributions to Wikipedia are appreciated, pages may bedeleted for any of several reasons.

You may prevent the proposed deletion by removing the{{proposed deletion/dated}}notice, but please explain why in youredit summaryor onthe article's talk page.

Please consider improving the page to address the issues raised. Removing{{proposed deletion/dated}}will stop theproposed deletion process,but otherdeletion processesexist. In particular, thespeedy deletionprocess can result in deletion without discussion, andarticles for deletionallows discussion to reachconsensusfor deletion. –Fayenatic London 10:25, 14 April 2022 (UTC)[reply]

References to many reviews of his books were added; notability per Author.Rgdboer(talk)04:37, 18 May 2022 (UTC)[reply]

The utility for mechanics was noted by Aleksandr Kotelnikov.

Do you have a source for"The utility for mechanics was noted by Aleksandr Kotelnikov."?I consolidating this history page:https://en.wikipedia.org/wiki/Cross_product#History— Precedingunsignedcomment added by'wɪnd(talk•contribs)13:36, 17 May 2022 (UTC)[reply]

The thesis he wrote at Kazan University refers to cross product in its title. Reference entered in History today.Rgdboer(talk)04:33, 18 May 2022 (UTC)[reply]

Great.:) Do you know if the paper is accessible somewhere in the Russian original, in a collection, translation, quoted, or otherwise a way to verify its content? I find nothing herehttps://zbmath.org/?q=ia%3Akotelnikov.a-pand a mention without source here:https://mathshistory.st-andrews.ac.uk/Biographies/Kotelnikov/'wɪnd(talk)16:06, 18 May 2022 (UTC)[reply]

Going toAll-Russian Mathematical Portaland entering 1895 and Kotelnikov generates an article in the University journal wherescrew theoryreplaces cross product in the title. Perhaps the thesisisthe article, with some translator substituting cross product. Thescrew displacementat the heart of the theory is a sufficient generator of theEuclidean groupE(3). Like the vector representation of the cross product, the screw displacement has ascrew axis.It involves both a rotation about the axis and a displacement along it. I have not read Kotelnikov’s work, but this Euclidean kinematic motion (somewhat related to cross product) is another subject, so the sentence you note may be a misdirection, so it can be deleted.Rgdboer(talk)17:10, 20 May 2022 (UTC)[reply]

Mention of Kotelnikov atCross product#Historyhas been removed as unverified.Rgdboer(talk)03:38, 23 May 2022 (UTC)[reply]

Screw theorylook fascinating!:) Thank you also for the pointer toAll-Russian Mathematical Portal.That will help me research another article I'm working on:https://en.wikipedia.org/wiki/Moment_(physics)#History

I've heard that Chebychev and others might have played a role in the origins of moments in probability theory and statistics, but I haven't found any direct attestations. This might help.'wɪnd(talk)20:48, 23 May 2022 (UTC)[reply]

Questions regarding your use of "beam space"

Hi Robert,

InRapidity,you introduced the notion of "beam-space" which is novel to me. For some time now, I have tried to find other references on this particular parametrization of the Lorentz transform and have not been successful. The nearest I have come is in some work by Garret Sobczyk where he makes use of a similar technique that he identifies as a novel type of spectral decomposition. In particular, I am interested in whether there is a "beam-space" version of (2+1) and (3+1) Minkowski spacetime. I have tried using a simple 3x3 matrix transformation, but I seem to be missing some crucial conceptual ingredients.

I have intended to contact you for some time on this topic, so I hope that I am not overly forward in writing directly to your wikipedia talk page. Please let me know if there is a better way to contact you (for instance, over email would be very convenient for me as well).

Sincerely yours,

John FriesJqgatsby(talk)22:41, 15 November 2022 (UTC)[reply]

Thank you for your interest in this topic. The answer in mathematics lies with the equivalence ofbinary quadratic formsxy and xx − yy. The points (x,y) satisfying the quadratic forms when set to 1 lie on hyperbolic curves. The latter is called theunit hyperbolaas it has minimal radius 1 while the other, a standard hyperbola, passes closest to the origin at (1,1), a distance of square root of two. Thenatural logarithmwas born from this standard, but the unit hyperbola is used with rapidity in spacetime. The equivalence of the two quadratic forms uses a linear transformation that moves the clock and meter-stick coordinates to the beam space. Perhaps the article onsplit-complex numbers,where the unit hyperbola replaces the unit circle, with its references 3 to 8 on spacetime interpretation, will be helpful. The stories of young Einstein imagining chasing light, and the two alternate directions, form a popular background to this topic. —Rgdboer(talk) 01:17, 16 November 2022 (UTC) RevisedRgdboer(talk)04:02, 16 November 2022 (UTC)[reply]

Let’s stick to two dimensions here, relating temporal to spatial metrics. The linear transformation

(x,\ t){\begin{pmatrix}1&1\\-1&1\end{pmatrix}}=(x-t,\ x+t)

has determinant 2 so the equivalence atbinary quadratic formdoes not apply.

Nevertheless, the connection of the twoquadratic formsis made linearly, and the form xy occurs when the asymptotes of the hyperbola are the coordinate axes. In the temporal interpretation, they are the beams to the left and right from a given (here, now). —Rgdboer(talk)01:10, 17 November 2022 (UTC)[reply]

SeeSqueeze mapping#Relativistic spacetimeandLight-cone coordinatesfor this concept. —Rgdboer(talk)02:24, 7 February 2023 (UTC)[reply]

Reference desk answer 23/09/23

Gregoire de Saint-Vincentnoted in 1647 that rectangular hyperbolas arestableundersqueeze mapping,so planar areas are preserved not only in the whole plane, but also under the hyperbola. Thus thehyperbolic logarithmdeveloped a century before Euler’s exponential functions a^x.

The correct statement is

\log x=\int _{1}^{x}{\frac {dt}{t}}

wheretis abound variable.

Here the case a>1 and b>1 is considered first so the areas extend to the right ofx=1 and the integral is seen as the area over [1,x] and under the hyperbolaxy=1. Usingbas squeeze parameter,

\log a=\int _{1}^{a}{\frac {dt}{t}}=\int _{b}^{ab}{\frac {dt}{t}}.

Then

\log b+\log a=\int _{1}^{b}{\frac {dt}{t}}+\int _{b}^{ab}{\frac {dt}{t}}=\int _{1}^{ab}{\frac {dt}{t}}=\log ab.

The cases where one or both ofa, bare in theunit intervalare similar whensigned areasare noted.

Copied here for ease of reference.Rgdboer(talk)22:34, 26 September 2023 (UTC)[reply]

Your edit inBinary relation

In your recent edit inBinary relation,you changed "functional relation" to "univalent relation" in the definition of this type of relation. This change leaves many occurences of "functional" (in this article) without any definition. Also, there are many articles that contain "functional relation" and certinly some of them redirect toBinary relation.Please, fix these issues.

By the way, perWP:LEAST,it is not a good idea to redirectUnivalent relationtoPartial function,and I have reverted this.D.Lazard(talk)12:55, 28 January 2024 (UTC)[reply]

IMO, "functional relation" must be restored in the article. However, this requires some care, as it appears that, depending on the author it may refer either to a function or to a partial function.D.Lazard(talk)14:20, 28 January 2024 (UTC)[reply]

The termfunctional relationis fraudulent. The redirect has been proposed for deletion. Inclusion of the term at Binary relation is expected to be removed. —Rgdboer(talk)22:28, 31 January 2024 (UTC)[reply]

Edit warring

You currently appear to be engaged in anedit waraccording to the reverts you have made onRelativity of simultaneity.This means that you are repeatedly changing content back to how you think it should be although other editors disagree. Users are expected tocollaboratewith others, to avoid editingdisruptively,and totry to reach a consensus,rather than repeatedly undoing other users' edits once it is known that there is a disagreement.

Points to note:

Edit warring is disruptive regardless of how many reverts you have made;
Do not edit war even if you believe you are right.

If you find yourself in an editing dispute, use the article'stalk pageto discuss controversial changes and work towards a version that represents consensus among editors. You can post a request for help at anappropriate noticeboardor seekdispute resolution.In some cases, it may be appropriate torequest temporary page protection.If you engage in an edit war, youmay beblockedfrom editing.-DVdm(talk)06:12, 13 March 2024 (UTC)[reply]

See discussion atTalk:Relativity of simultaneity#Conjugate hyperbola & diameter—Rgdboer(talk)02:22, 15 March 2024 (UTC)[reply]

Yes,dosee discussion atTalk:Relativity of simultaneity#Conjugate hyperbola & diameterindeed. -DVdm(talk)08:03, 15 March 2024 (UTC)[reply]

Administrator research

Research:Wikipedia_Administrator_Recruitment,_Retention,_and_Attritioncontains a link to a project surveying Administration. —Rgdboer(talk)00:53, 25 October 2024 (UTC)[reply]
updated:Wikimedia research page—Rgdboer(talk)00:57, 13 November 2024 (UTC)[reply]

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If you wish to participate in the 2024 election, please reviewthe candidatesand submit your choices on thevoting page.If you no longer wish to receive these messages, you may add{{NoACEMM}}to your user talk page.MediaWiki message delivery(talk)00:06, 19 November 2024 (UTC)[reply]