User talk:Quondum/Archive 4

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Archive 4

Flat'n sharp

Thank you for [this edit]. I don't store the complete unicode character tables stored in my memory, and actually anticipated your edit. (Normally I'd just have asked.) YohanN7 (talk) 14:17, 19 July 2015 (UTC)

And the point of mentioning a trivial edit on my talk is what? I hadn't noticed that that section had just been added so recently, since I was not looking at a diff. —Quondum 14:57, 19 July 2015 (UTC)

The point is to let you know that I am not mad at you for this. YohanN7 (talk) 15:22, 19 July 2015 (UTC)

You have a distinctly oblique way of communicating that; it could have been interpreted as an expression of irritation. Even Maschen has evidently grown guardedly neutral in these interactions. —Quondum 15:37, 19 July 2015 (UTC)

You're correct Quondum, I have been neutral in these interactions by neglecting your lecturing authoritative tone, and never ever, not once at all, challenging what you say. In future I will not hold back challenging what other editors say when they make confident statements without sources. I will actually think, compose my answer, and back it up by sources. M∧Ŝc²ħεИ_τlk 15:53, 19 July 2015 (UTC)

Good to know; it's a pity if you felt thus constrained in the past. Though I would have appreciated knowing earlier about the apparent antipathy on your part. Clearly my communication style leaves something to be desired. —Quondum 16:10, 19 July 2015 (UTC)

For one thing, it would help if you used less elaborate language and not ramble on talk pages especially talk:Thomas precession (hence your own principles of clarity and terseness when writing).

For another, the Thomas precession incident just highlights that you do write with an authority, and when others disagree because people "couldn't align the basics" with what you said, you just walked off. The fact you even made an accusation that we (YohanN7 and myself) were the ones doing OR despite the sources provided, while you made a statement without sources, was just hypocrisy. Surely you realize your dialogue throughout the incident started off authoritative but ultimately was rather childish/stroppy? This is not an insult, it is an honest criticism.

That said, I wasn't "feeling constrained" in the past. I just didn't make any effort to challenge in case I appeared forceful on my own ideas, and since your collaboration has long been positive I was willing to follow your lead. M∧Ŝc²ħεИ_τlk 16:23, 19 July 2015 (UTC)

Though I would have appreciated knowing earlier about the apparent antipathy on your part.

Would you? I am less polished than M (but probably more than IM) and have let you know. The result is just a more condescending tone from you.

The interesting observation is that the product of the level of superiority in your tone with the level of your actual knowledge of the subject at hand seems to be fairly constant, sk = C. I made this observation long ago. It makes it unbearable to discuss with you those times when you are almost totally lost and consult your intuition that you, evidently, hold higher than verifiability, and closer to the truth than what published scientists claim. YohanN7 (talk) 16:32, 19 July 2015 (UTC)

M, yes, my interaction degenerated. I would hope that you consider me as a person who has an opinion, not someone who comes across as being authoritative. My behaviour after that was all downhill, and my withdrawal was primarily due to my own excessive reaction and inability to comport myself.

Y, perhaps you are missing a nuance here: the difference between considering past actions and their impacts (as M is doing), and making characterisations and generalizations about a person (as you have done in your post above). —Quondum 18:15, 19 July 2015 (UTC)

No, I didn't miss it. And you aren't in a very good position to attack. I just said in the very same post that am less polished than M. Someone must tell you sooner or later I figured, rightly or wrongly. After all, you yourself wished that M had been blunt earlier about you tone, did I get that wrong too?. As for me, I honestly believe that you are a very valuable positive force at WP over all, and I'm perfectly willing to let this all be forgotten. We could probably discuss the issue further over email, the three of us if you want to. I have plenty more to say about your modus operandi (but I am not that unpolished that I'd say it here), and I'm sure you have things to say in return too. Time to clear the air. YohanN7 (talk) 19:01, 19 July 2015 (UTC)

Q, I still do find you a valuable editor because you express opinions. Nothing wrong with commenting or questioning if something does not make sense.

However, after looking through more of your interactions (including those with YN7), you are certainly not destructive or nasty, but do seem to latch onto your views, and if a discussion fails to head in the intended direction then you exit, sometimes with an unhappy remark as if the others involved should change their mind. I am not dwelling on past interactions for the sake of it, they are relevant because it seems like a behavioral pattern, and the very recent incident was no better. I have never seen you be as counterproductive as this.

My posts above were not to extract apologies or confessions, just to say what was needed to be said. That's all. As YN7 says time to move on. M∧Ŝc²ħεИ_τlk 19:36, 19 July 2015 (UTC)

Y, the email approach was an unmitigated disaster on the previous attempt, and you make it sound like you are seeking to pick up the hatchet rather than bury it.

M, I am trying to steer clear of the behaviour by early diagnosis of a degeneration of an interaction, but am clearly not so successful. Yes, time to move on, but not to clear the air. —Quondum 20:13, 19 July 2015 (UTC)

On WP it just boils down to what the references say. Remember I have admitted part of the incident was my fault too, I should have just clearly stated that in the original papers (by Mocanu and Ungar) the diagrams were based from, the space-like axes in the frames remain orthogonal, and that would have saved considerable time and energy. If you had no access to the sources, and wanted to verify anything, you could have just asked. If you had sources which supported your view then there's nothing wrong with pointing to them. None of this happened... Anyway this is my last post here today. M∧Ŝc²ħεИ_τlk 20:30, 19 July 2015 (UTC)

Yes, time to move on, but not to clear the air.

Another attempt to regain authority and control by trying to make someone else inferior because he thinks he spotted a wiki no-no. Quondum is not interested in changing behavior by his interactions here.

He reserves his rights to say anything and remain unquestioned. Right M, you will not find any explicit rudeness in Q's posts. You'll just find the tone, like edit summaries, dripping of sarcasm, saying "really?", when he has dropped a boo-boo on a talk page. It is part of his well tuned mode of operation. He disqualifies me and my arguments because I have stood up to him in the past. Such things are not allowed in his world. He thinks he can get away with anything since any questioning of his behavior (and particularly his knowledge when he is on a spree) counts as a personal attack, and must therefore be disregarded. Perhaps true Q, you'll win the battle, but you'll not win the war. The real war you have to fight is against yourself. Do it! YohanN7 (talk) 11:05, 20 July 2015 (UTC)

To editor YohanN7: I regard this as unwelcome and unnecessary harassment. Do not post in my user space again. —Quondum 14:55, 20 July 2015 (UTC)

Metric Signature

By the definition stated, the metric signature of the matrix [a-11 = a-22 =0; a-12 = a-21 = 1] should be (0,0,2) and not (1,1,0) as stated. ( Main diagonal number of positive entries, main diag # neg entries, main diag # zeroes ). sorry for cumbersome notation. Doug

no save button or option shows!!!

DougW.R (talk) 23:41, 27 July 2015 (UTC)

I presume you are referring to Metric signature § Examples §§ Matrices.

You will notice that in that section it specifies a diagonal matrix; only the first of the two matrices in that section is in diagonal form. The second matrix must first be diagonalized before counting values to determine the signature. The definition (Metric signature § Definition requires an orthogonal basis for the metric to be applied to, which is equivalent to the diagonalizing requirement for a matrix.) So it seems to me it is correct as written, albeit not necessarily very clearly explained. —Quondum 01:23, 28 July 2015 (UTC)

Geometry of special relativity

hi In the WP article on absolute geometry I came accross the sentence "geometry of special relativity " so I decided to change it to geometry of special relativity , but I am no expert on relativity, (I don't even know the differennce between general and special relativity]], NO,NO I want to keep it that way :) and I could do no better than temporary make it into a redirect to spacetime.

Could you or some of the other contributors to this page let this page grow to a full article. (ps i don't know a better place to put this, please tell me where that better place is) WillemienH (talk) 10:37, 1 August 2015 (UTC)

I've changed the redirect geometry of special relativity to point to Minkowski space rather than to Spacetime; I felt that this was a more geometrically and less physics-oriented target; I hope you don't mind. Absolute geometry is already classified under Category:Classical geometry, and I can't think of anything else. Posting an invitation at WT:WPM is a possibility, but seems maybe too wide a forum to post for help on every article one is working on. Maybe it is best to just allow others working in the area to wander across it as they have time; it does not seem to me that it is worth diverting attention from other areas; there must be thousands of articles in similar need of attention. My own interest in geometry lies more in the Erlangen program rather than in synthetic geometry. —Quondum 15:46, 1 August 2015 (UTC)

Thanks, you are more knoledgable than me in (any kind of) relativity, so i don't mind. But about the other point I do prefer synthetic geometry above the Erlangen program, but we can all have our own preferences :) WillemienH (talk) 18:16, 1 August 2015 (UTC)

It might have been nice to have had an article on Minkowski space from a pure geometer's perspective. However, since this is an object that physicists use, this seems unlikely. And I agree, we all have our preferences – and this makes the world a more interesting place. —Quondum 20:42, 1 August 2015 (UTC)

Invitation

Dear Quondum, Please send me an email at cyberflor@aol.com I am interested in getting to know you personally. It seems we have several common interests. Thank you. -m Please forgive me if I have not left you this message correctly. I normally do not contribute to Wikipedia.73.46.237.225 (talk) 05:45, 7 August 2015 (UTC)

Context needed

Hi, Quondum! I have noticed while browsing wikipedia your contribution from nuclear magnetic moment from april this year where you demanded more context for an edit regarding subadditivity or superadditivity of nuclear moments. Could you specify what could/would that be? Thanks--86.125.162.41 (talk) 19:49, 23 August 2015 (UTC)

For context, you seem to be referring to this edit (with the edit summary without more context, this is a pretty meaningless statement), where I reverted the addition of the statement struck in the following:

The nuclear magnetic moment varies from isotope to isotope of an element. Nuclear spin and magnetic moment are both always zero in a ground state (lowest energy) nucleus, if the numbers of protons and of neutrons are both even. In other cases, with odd numbers of either or both protons and neutrons, the nucleus often has spin and magnetic moment. This quantity is not the sum of magnetic moments of nucleons, in other words has no additivity property.

Leaving aside that "This quantity" is difficult to parse (but evidently refers to the nuclear magnetic moment rather than to the nuclear spin), it is unclear why this should be important (i.e. why bother to mention it), and also why additivity of magnetic moments should not hold. I can understand that orbital spin of charged particles (protons) would contribute to magnetic moments in addition to nucleon magnetic moments, but without elaboration, the statement creates far more questions than it answers. For example, if such a statement were to be made, examples of how much the magnetic moment of a nucleus with one more neutron than another differs appreciably from that of a neutron would be helpful, as well as an explanation of the difference. —Quondum 02:04, 24 August 2015 (UTC)

Nuclear magnetic moments (non)-additivity

Hi! Regarding a topic of a previous conversation now in your talk page archive I agree about the necessity of displaying values for some (simple) nuclides which illustrate the non-additivity of nucleon magnetic moments. This source [1] discusses the topic and it says that the details of origin of non-additivity are lacking or unclear. Some explanations have been tried. Experimental data of nuclear magnetic moments should be taken as is, regardless of the proposed explanations which may be weak.--86.125.183.45 (talk) 09:49, 8 November 2015 (UTC)

IMO, the source provides reasonable context, and is understandable to the general reader. In particular, it makes it clear that additivity of magnetic moments does hold approximately, and non-additivity can be treated as additivity with a deviation. I would be comfortable if it was captured in the text this way. —Quondum 02:32, 9 November 2015 (UTC)

Additivity with a deviation seems a general procedure in dealing with idealized and non-idealized scientific concepts. Some examples includ: ideal solution and non-ideal solution (where non-ideal solution has deviation from additivity of volumes of components encountered in ideal solution, deviation expressed in activity coefficients) and ideal and real gas (where the deviation from ideality can be expressed both additively (V - RT/p) and multiplicatively by compressibility factor Z = pV/RT different from unity which characterize the ideal case).--86.125.185.29 (talk) 09:06, 11 November 2015 (UTC)

Yes, and this is readily understood by the reader. The place for this discussion is at Talk:Nuclear magnetic moment, not my talk page. Please feel free to discuss there and to edit the article, preferably adding references. My contribution is likely to be very limited. —Quondum 16:03, 11 November 2015 (UTC)

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Ordinal suffixes

You are correct about ordinal suffixes. Next time, please provide a reference to the Manual of Style when you make your edit -- especially when the rule is counterintuitive or clashes with day-to-day practice. This manual has grown so large and is now so detailed and normative that many people are likely to make mistakes in bona fide. Thanks. J.P. Martin-Flatin (talk) 06:32, 19 March 2016 (UTC)

Yes, I apologize – I have become lazy, since I often make collective (mainly noncontentious) format edits to articles on mathematics (roman/italic/bold, <math>/{{math}}/{{nowrap}}, spacing, punctuation, n^th/nth, hyphen/en-dash/em-dash/space/nbsp, ×/∗/*/^∗/^*, ⋅/·/• and the like) and have started assuming familiarity and acceptance of these formatting changes by the other editors, simply using the edit comment "fmt". I realized when you reverted me that I'd failed to adequately comment my edit, but a separate talk-page explanation seemed unwarranted so I just put the explanation with my subsequent revert. I certainly did not mean to imply that your revert was anything but well-intended. Almost every change of this nature is counter to someone's day-to-day practice, but I take your point: the editor who is relying on the MoS should reference it. —Quondum 16:40, 19 March 2016 (UTC)

Linear map as module homomorphism

Can you provide a reference for module homomorphisms defined between modules over different rings? The page at module homomorphism is consistent with the statement that a linear map is a module homomorphism, but your suggestion [2] is intriguing. Quiddital (talk) 21:50, 5 May 2016 (UTC)

I have no reference that says so. I probably meant that there exist module homomorphisms that are not linear maps because they are not homogeneous, and I suspect that I had a case in mind that forced this conclusion.

An illustration, but perhaps not one that forces the conclusion: the mapping of the complex numbers as a vector space over itself defined by complex conjugation is not C-linear, but I would contend that it is a module isomorphism. One speaks of vector spaces in which the scalars are only implied (for example abelian groups are Z-modules), and one does not need to identify the sets of scalars of two abelian groups to claim that they are homomorphic as groups and hence as Z-modules. —Quondum 06:54, 6 May 2016 (UTC)

The least element of the subset ω+Z:

I've thought again about your question, and here is the correct answer: What is only provable by First order Axiom of induction is about the least element satisfying a given First order proposition, rather than about the least element belonging to a given subset. So, really your subset ω+Z has no minimum, but First order Peano language can formulate no proposition φ(x) satisfied only by every x belonging to your subset. HOTmag (talk) 12:06, 9 August 2016 (UTC)

I'm a rookie with the Peano axioms, but I was just trying to point out what seemed to me to be an error in the reasoning. Identifying such an error does not require the rest of the system to be understood. The apparent error involved concluding that one could prove a statement that was expressible as a first-order statement (that there existed an element that satisfied a given proposition) using a wellordering. However, my reasoning was not followed, so it seemed best to exit the discussion.

I don't quite follow what you say above (the logic is not clear to me), but I suspect that your conclusion (that no proposition that identifies nonstandard elements exist) is true. —Quondum 15:13, 9 August 2016 (UTC)

I was referring to what you'd said here: "Okay, so how is the well-ordering principle a consequence of the axiom of induction? My example of a nonstandard model seems to an example that violates the principle, but does not violate the axiom of induction. To recap: The well-ordering principle says that every subset of the model has a least element. My model has a subset, namely ω+Z, that has no least element under the ordering <. Thus, < is not a well-ordering in this model ".

So I explained that your model, which has a subset (namely ω+Z) having no least element under the ordering <, does not disprove the fact that the well-ordering principle is a consequence of the First order Axiom of induction, because the "consequence" of First order Axiom of induction is about the least element satisfying a given First order proposition, rather than about the least element belonging to a given subset. So, really your subset ω+Z has no minimum, but First order Peano language can formulate no proposition φ(x) satisfied only by every x belonging to your subset. HOTmag (talk) 16:52, 9 August 2016 (UTC)

So as I synthesize this, you are saying that since no first-order proposition can exist that is true exactly for nonstandard elements, we cannot have a proposition that switches truth-value "between" the nonstandard and the standard elements. And thus there must be a least value at which it does switch, whether this is at a standard or nonstandard element. (I still have to think through the premise here, but I'm not arguing against it.) —Quondum 18:26, 9 August 2016 (UTC)

Your first sentence ("since no...standard elements.") is correct. However, your second sentence ("And thus there must be a least value...nonstandard element.") is not clear to me, because the "least value" I'm talking about is related to a first order proposition (as I've explained many times) - whereas you mentioned no first order proposition when you mentioned the "least value". HOTmag (talk) 19:08, 9 August 2016 (UTC)

I meant "And thus there must be a least value at which it [the truth value of any given first order proposition] does switch ...". But I have also been assuming by "least" that a total ordering < is well-defined, and matches our perception of it (in particular that if we somehow define +, a<b ⇔ ∃x(a+S(x)=b), even though for my logic < need not itself be expressible as a first-order preposition. I may be glossing over similar points due to me making assumptions without realizing it. —Quondum 19:57, 9 August 2016 (UTC)

The order < must satisfy: a<b ⇔ ∃x(a+S(x)=b), and it's also well defined by that first order definition. HOTmag (talk) 09:55, 11 August 2016 (UTC)

I'm not sure which definition you are referring to when you say "that first order definition". Nevertheless, my original point was that this < is not a wellorder, and hence the wellorder principle does not seem to apply. Remember, I was arguing about the logic, not the conclusion. Anyhow, I'm not sure where we're headed with this: my knowledge of the area is very poor as I've already pointed out, and until I study a lot of the basics in this area, I am liable to tripping over things. —Quondum 16:13, 11 August 2016 (UTC)

I was referring to the definition I'd just mentioned, i.e. a<b ⇔ ∃x(a+S(x)=b), and this order < - defined by that first order definition - is a wellorder in the following sense: Every first order formula φ(x) with x as a free variable, has (under < ) a least element x satisfying φ(x). Further, this fact is a consequence of the axiom of induction. That's what I've been claiming from the very beginning, and I wonder what isn't clear yet - even to you (and to everybody who has elementary knowledge in logic, even without knowledge in Peano axioms). HOTmag (talk) 17:19, 11 August 2016 (UTC)

We are clearly running into communication clarity issues. For example, something introduced with the words "must satisfy" does not qualify as a definition, yet you've just referred to it as a definition. We clearly have a number of these little disconnects to settle before we both will be using the same terminology. Let's discontinue this. —Quondum 18:04, 11 August 2016 (UTC)

Just for the sake of clarity: By "must satisfy" I meant, that since the order < is defined (in Peano system) by the statement: a<b ⇔ ∃x(a+S(x)=b), then (as a result) it must satisfy that formula (as far as Peano system is concerned). In other words: not only must the order < satisfy that formula, it is also defined by that formula. Sorry for not making it clear from the very beginning. HOTmag (talk) 19:05, 11 August 2016 (UTC)

Replacing mathematics markup: Lattice (order)

Could you please explain why you have wholesale replaced the mathematics markup in the page Lattice (order) with hardcoded markup, including extensive use of the nowrap template to ensure reasonable results? Such changes significantly reduce the accessibility of the page to those with reduced vision and especially using screen readers, and I am considering reverting your change altogether. At the least such large scale changes should be flagged at the article's talk page. Ott2 (talk) 13:01, 29 August 2016 (UTC)

At the outset, I'll mention that I don't have much of a personal stake in this, so if what I say here does not make sense, you may as well go ahead.

That said, there are several different types of format change that I made:

• Insertion of spaces: inclusion of space around binary operators (e.g. ≤) seems to be encouraged by the MoS, and is probably not controvertial – except that it might break across lines when at the end of a line on the screen.
• Using HTML markup (double apostophe) to change variables from roman to italic. This is standard, and is simply a change for consistency.
• Replacement of inline formulae in math tags with HTML markup (excluding the use of the nowrap template). This is one where there is little consensus. Inline latex markup has size issues etc., and I have not seen a suggestion that this helps for screenreaders or other accessibility issues. Many instances in this article were sporadic (i.e. inconsistent) display of unusual symbols such as ∧ (which have Unicode equivalents) inside otherwise HTML formulae. Since the majority of inline math formulae were in HTML, changing these cases to HTML for consistency seems reasonable.
• Replacing stand-alone maths formulae previously in math tags with HTML markup. This is actually contrary to the MoS, but since this was already overwhelmingly the case, I felt that this was the appropriate direction to change for consistency. One could make a wholesale change in the opposite direction.
• Introducing nowrap templates to prevent mid-formulae linewrap. This introduces, <span class="nowrap"> HTML tags in the viewed page, which I would expect screenreaders to ignore. I have introduced nowrap templates extensively in many math articles, and this is the first comment that I've received about this. If this does indeed reduce readability as you suggest (and it is not clear to me that it would), it is a significant matter that should be addressed in WP:MoS.
• Since rendering of \bigwedge and \bigvee in several fonts might be poor, I did not touch these as an exception. This is a residual inconsistency.

I'm not persuaded that alerting others on the talk page about simple format consistency changes on the talk page would be helpful, wholesale or not. In all, this (the accessibility impact) sounds like something that should be discussed at WP:MoS. If what you say is valid, then I would be interested in the preferred style, and I feel that this should be captured as a guideline in the MoS. Dealing with it at the article level does not seem appropriate. —Quondum 14:48, 29 August 2016 (UTC)

Alternating map

Your recent edits of the article alternating map cause an inconsistency in the terminologies used in the articles alternating map and tuple. If you think that element is not the right term for an object in a tuple, please edit the article tuple accordingly and add a note to its Talk page. If others agree with you, then feel free to update the article alternating map as well. Thanks. J.P. Martin-Flatin (talk) 13:14, 21 September 2016 (UTC)

Consistency with another article as the *sole* reason for opposing and reverting another editor, without addressing their stated reason, is inappropriate in Wikipedia. Please note that previous objections to my edits were based on a terminology change; your latest revert was not. Vetoing edits to one article based on a demand that consensus be arrived at in another article is ridiculous.

To address your concern more directly: editing WP to achieve consistency with outside sources is the objective. Seeking internal consistency without reference to outside sources is not, and should never be. Internal inconsistency is merely an indicator that research into sources is needed.

Please try to be more constructive. Respond to the stated reason in my edit summary for the edit that you reverted. —Quondum 15:10, 21 September 2016 (UTC)

I wish you were more constructive, too. I am not trying to impose consistency with a randomly chosen article on Wikipedia. I am talking about the first sentence of the article tuple, which I did not write, which reflects a certain consensus in the community, which defines the concept of "tuple" by using the term "element" with the same link as the one I put in, which clashes with your proposed change, and which clashes with well-known references such as

Serge Lang, "Algebra", revised 3rd revision, Graduate Texts in Mathematics, Vol. 211, Springer, 2002, page 511, §4, line 15 ("when two adjacent elements are equal").

J.P. Martin-Flatin (talk) 08:02, 22 September 2016 (UTC)

One might note that the bulk of the article, including text concerned has been obliterated recently, making this somewhat academic.

I know that Serge uses the term 'element', but this is about the linked meaning, so I do not see how this clashes with Serge. Simply using the same term 'element' does not mean that 'element of a tuple' is synonymous with 'element of a set'. A tuple is an element of a Cartesian product. The term 'element' gets used plentifully in Cartesian product, but never to refer to the element of a tuple, only to the element of a set that contributes to the product of sets, and to the tuple as an element of the Cartesian product (being a set of tuples). It is valid and common to refer to an element of a tuple, as as Serge does, but I maintain that the meaning is distinct, since a tuple is not a set. I have not managed to sensitize other editors to this distinction, and I don't care enough to invest the energy. So deal with this as you will; I will step back from it. —Quondum 15:19, 22 September 2016 (UTC)

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Help

Hi Quondum, I was wondering if you could take a look at Modular multiplicative inverse. I seem to be having some trouble with a novice editor with a low quality reference and some strange concepts. I have probably miffed her (I think) with some of my edit summaries and I don't want to get into any type of edit war. I'm pretty sure that my edits were not stellar, but they could have been improved upon. On the other hand, she seems to now think that the topic has nothing to do with ring theory! Thanks if you can manage this. --Bill Cherowitzo (talk) 02:31, 13 January 2017 (UTC)

It might be worth taking it to the talk page while ignoring what happens in the article for a day or two. I've dropped a note on the user's talk page. I'll look at opening a discussion on the article's talk page. —Quondum 06:31, 13 January 2017 (UTC)

Thanks. I just finished posting on the talk page with just that intent.--Bill Cherowitzo (talk) 06:48, 13 January 2017 (UTC)

Bouncing ball

Since you took an interest in the article, would you mind doing a DYK review or a GA review for it? Headbomb {talk / contribs / physics / books} 18:21, 18 February 2017 (UTC)

I appreciate the request, but I would not be able to do either justice. My interest (and ability to focus) is largely at the proofreading level, and a review would be beyond me. The article reads well and leaves a good impression. § Multiple stacked balls seems like it might need generalization. —Quondum 19:35, 18 February 2017 (UTC)

Fair enough. Not quite sure what you mean about the multiple case needing generalization though. Do you mean it should talk about n balls being stacked together? Headbomb {talk / contribs / physics / books} 20:01, 18 February 2017 (UTC)

No, I was thinking more along the general lines of transfer of energy, momentum and angular momentum between two objects in a collision. The rest of the article is comprehensive, covering many mechanisms affecting drag and bounce. The section as it stands seems to be too focused on a "party trick". The idea is elaborated in some of the references, which show that the coefficient of restitution is sometimes a small contribution to rebound behaviour in sports (e.g. ball off a racquet) but is over-emphasized in sport regulations that focus on rebound from a hard massive surface. The hook of the DYK is also not elaborated on, relying on the reader to connect the multi-ball stack with a supernova explosion, which seems a bit popular-sciency: it is a nice illustration, but is not obviously hard science. —Quondum 20:27, 18 February 2017 (UTC)

Riemann sphere

In a recent edit to homography you asserted that the Riemann sphere has more structure than the Complex projective line, which redirects to Riemann sphere. Looking over the article it is not clear where the extra structure lies. Do you mean that the sphere is immersed in a 3-space ? There doesn't seem to me to be any difference between them as real or complex manifolds. — Rgdboer (talk) 21:48, 23 May 2017 (UTC)

I do not mean that the Riemann sphere is immersed in 3-space, nor is there any difference as manifolds. Can we agree at least that the extended complex numbers and the complex projective line are not the same thing? (The former has a natural mapping from the complex numbers, the latter has no such natural mapping.) The article Riemann sphere is not particularly satisfactory with regard to defining exactly which meaning is intended for the term; I have assumed the former because I've most often seen it used where the added structure of the mapping from the complex numbers is necessary, though it may be that it is variously used to mean any of the several inequivalent structures described in the article. Or maybe it used as an umbrella (i.e. poorly defined) term, and the intended meaning must be ascertained from context? —Quondum 01:49, 24 May 2017 (UTC)

Actually, I would be happy with a reversal of my edit summary: re-reading the article, it is essentially consistent with the interpretation of the Riemann sphere as the complex projective line, but with the extended complex numbers having more structure. Either way, it would be nice if which is meant by the term "Riemann sphere" was clearer in the article. —Quondum 02:03, 24 May 2017 (UTC)

There are two standard steriographic projections for the Riemann sphere: one with a plane Tangent to the South Pole, the other with the plane defining the Equator. Both cases use North Pole for the center of projection. Likewise, there are two canonical injections of the complex plane into its projective line, one into the first homogeneous coordinate, the other to the second. As for usage, RS as the compactification of C is most common. Unfortunately many contempories don't do homogeneous coordinates or projective geometry, so even if they use Mobius transformations frequently, the projective view is lost. Thank you for your many efforts improving the Encyclopedia; we see double-naming is frequent, as is ambiguation.

In light of my ruminations above, I feel more comfortable reverting my edit and have done so. I definitely agree with your comment on name-reuse and ambiguity. —Quondum 04:11, 24 May 2017 (UTC)

dots

This edit is a bit confusing because the edit summary says in part "middot → sdot" but the dot you inserted is descried in the Microsoft Windows Character Map program as "U+00B7: Middle Dot". I don't know what "sdot" means. Jc3s5h (talk) 15:36, 17 July 2017 (UTC)

What I did (or at least what I think I did, and on checking I find no error) was to replace · (·, U+00B7: MIDDLE DOT, available in the "Insert" editing character set at the bottom of the edit window) with ⋅ (⋅, U+22C5: DOT OPERATOR, available in the "Math and logic" editing character set). I did not spell out the HTML code, which makes it more difficult to see what I did, but it is the same character. The reason for my replacement is that the middot is intended as a list separator, and some fonts treat it more sloppily, a like a bullet with varying sizes between fonts and asymmetric left-right spacing. The dot operator, on the other hand, is intended as a mathematical symbol such as for multiplication (the exact meaning here), and fonts consequently treat it accordingly (more symmetric spacing etc.). Perhaps I was being presumptive in my labelling of the edit: not all editors know the HTML entities codes as supported by WP. —Quondum 16:10, 17 July 2017 (UTC)

There is a significant problem with U+22C5. On Microsoft Windows, it is not provided in Seago UI, which Microsoft describes as "the Windows system font". Nor is it present in Arial, which in my experience has been the best choice when a good variety of Unicode character support is wanted. So U+22C5 is hard to work with for many readers. Can you state where U+00B7 is described as being a list separator? Also, my experimentation indicates that U+00B7 is the character used in NIST Special Publication 811. Jc3s5h (talk) 16:48, 17 July 2017 (UTC)

I agree that font support for mathematical operators is a potential problem, but then this would be a larger problem. I have used U+22C5 extensively in WP mathematics and physics articles, with nary a peep, so it can't be a "significant" problem. The "Mathematical Operators" block (U+2200 to U+22FF) was introduced in Unicode version 1.1 in 1993, only two years after the original Unicode standard was published, so lack of support must be categorized in one of in two ways: that the designers of a font never intended the font for anything semi-technical, or they intended the additional blocks to be supported along with the font in some other way, such a through font extensions or variations (I expect automatically invoked by software as part of a font family). Indeed, Segoe § Segoe UI §§ Variations tells me that Windows 7 does support Segoe UI Symbol, and thus I would expect no problem from Windows 7 onwards. Similarly, a variation of Arial, namely Arial Unicode MS (supported by Microsoft Word since 1999) does support this block. The link you provided does not mention that Segoe was only introduced in 2007 with Windows Vista. Since Vista never gained much popularity, references of this nature should be to Windows XP, which means Segoe should not be our reference. I have never found a problem on my Windows machines (even with Arial selected as default font on my browser) that it cannot find the character; I use 7 and 8. In all, I think this is not really the approach we should be taking.

My rule of thumb is: if a character is provided in a WP editing tool, it has been deemed fit for use in WP articles. Also, since the WP math community is at the forefront of the font issue due the need for unusual symbols, they are perhaps most sensitized to ensuring that the text is viewable to the vast majority of WP readers, and I think I would have heard about this one. If there are general font issues, these should be addressed by the WP:MoS (which I find strangely silent on the topic) and the default editing tools, not on a per-article basis. That is: if this is genuinely a problem for more than a tiny number of readers, we should first deal with it at the MoS level. Which basically raises the question: have you observed an actual problem where the sdot character is not supported, or are you just going by inference? (And yes, I have noticed that NIST uses U+00B7, but I do not consider their typographic choices to be a guideline in WP; not even their explicit rules on formatting of quantities is followed exactly by the WP MoS: witness the space before "%".)

On your question, Interpunct is informative (I see it mentions U+2219 too). The interpunct is listed as a word divider in the navbox, but I guess you should ignore my earlier comment (a half-memory) about its intent. —Quondum 19:29, 17 July 2017 (UTC)

A barnstar for you!

	The Original Barnstar
	I thank you for what you have done and continue to do. I have learned so much so quickly from entries like "Planck units" and there you are -- June 15 -- helping to shape it and make it more substantial. I say, "Thank you!" and readily understand how the human family can enervate anyone. Be well. Be happy. 81018CMBR (talk) 14:04, 19 June 2017 (UTC)

This is well-deserved Q. YohanN7 (talk) 11:23, 19 July 2017 (UTC)

4-Gradient

Hi Quondum,

I appreciate your edits on the Four-Gradient page. I was wondering if I might enlist your aid on a non-wiki physics-related project. If you are interested, you can reach me at SciRealm@aol.com Thanks, John Wilson — Preceding unsigned comment added by 208.104.84.162 (talk • contribs) 14:58, 24 July 2017 (UTC)

Re your ping on Rschwieb's talk

First of all, please, let me ensure that in no way I intend to offend anyone, and that I myself do not feel touched to the least extent in the course of these matters. All my deeds in this context were guided by the effort to do them at the right place in the appropriate manner, always being fully de rigeur, but meanwhile bewildered.

1. I was drawn to GA by a correction and dropped, as a a drive by edit, an abbreviation of the caption under discussion. As an aside, I noticed in the last moment how projection and rejection were used in the article and saved accordingly. My first attempt used just projection on orthogonal subspaces.
2. My edit was reverted by Rschwieb. Since I never even thought of discussing my edits with an expert, valuating them as negligible myself, I decided to deposit, directly at his talk, my reservations against his formulation, and against rejection in general, assuring, me not further interfering with his edits. This appeared to me as being more appropriate, than to make this slight disagreement public via the article's talk, and discuss this at length, and thereby also transferring the responsibility for accurateness to Rschwieb.
3. In the sequence you edited the caption and the article's text, directly meeting my understanding, and so I updated my comment to inform Rschwieb about my last appreciation.
4. Next, I marginally edited the caption, just enjoying its new wording.
5. Then I noticed your ping, read your comment, and now I am confused. Neither do I get why you put your comment about my behaviour there, instead of on my talk, nor do I know where my fault was, in having put my first comment on Rschwieb's instead of on the article's talk, nor am I sure about me not being embarrassing again by writing this on your talk.

Under all circumstances, please, take my incipient assurance as absolutely serious. Any enlightenment highly appreciated. Purgy (talk) 13:35, 17 August 2017 (UTC)

I did not intend any rebuke at all, and I have seen throughout that you have the best intentions. I am simply trying to encourage you to be a bit more bold, and post your opinions on edits in a more general forum, because I notice that you sometimes use user pages for this where their audience is limited. Your opinion is as valid and valuable as that of any editor. Your reservations about the wording at GA were good and reasonable, and I am glad you pushed it in the direction that you did. So, in short, you should feel embarrassed about nothing, and be confident of your own opinion! You are welcome to post here and anywhere else you choose. —Quondum 17:12, 17 August 2017 (UTC)

Thanks! These belong among the nicest words I encountered here at WP. Nevertheless, I'll forego to be more bold than I am currently, I just wanna have fun in WP, and do not intend to do hard work, dig deep holes or lift heavy stones, not even to break up slight encrustations ("i² = -1" is BAD, Naturals long for their(sic!) multiplicative neutral, ...). No, not anymore.

This encounter was my pleasure, and I look forward to meet again by chance. Purgy (talk) 06:39, 18 August 2017 (UTC)

Yeah, I echo your feelings: I've had my own negative interactions, and have shied away. (And the √−1 problem seems to relate to an entrenched set of unwritten rules in real/complex analysis, but which pervades mathematics.) Go well! —Quondum 12:01, 18 August 2017 (UTC)

Terminology

Regarding this edit and your edit summary. I'd rather say "three-space momentum", "three-space velocity", etc, is an invention. It exists but is utterly uncommon, and I haven't seen it in any "heavy" RS. You can confirm this using Google scholar. YohanN7 (talk) 09:30, 8 September 2017 (UTC)

Is what it replaced (e.g. 3-velocity) any better? —Quondum 11:33, 8 September 2017 (UTC)

Either 3-velocity or three-velocity (etc) would do equally well (about same number of Google scholar hits, some 100 000 as opposed to 20), and since we have adopted in our articles four-velocity, not 4-velocity, I'd say three-velocity and three-momentum is the best choice. YohanN7 (talk) 11:43, 8 September 2017 (UTC)

The vast majority of your hit count does not relate to this meaning. However, I do not intend to debate this with you: please move this to the talk pages of the articles concerned. —Quondum 12:07, 8 September 2017 (UTC)

What "vast majority"? I glanced through the first 50 hits (Google scholar will highlight), and all relate to this precise meaning: "three-momentum", "3-momentum" and your "three-space momentum". You are the one who is "arguing".

Just self-revert instead of wasting time. No need to bring the bleeding obvious to various talk pages. YohanN7 (talk) 12:55, 8 September 2017 (UTC)

Where else?

Please tell me, where else did you put in the terminology in the above thread? YohanN7 (talk) 07:07, 13 September 2017 (UTC)

Symbols and stuff

Sorry about the confusion - we were talking at cross-purposes. Please also note that I corrected a typo in your comment ("Please also not that..."); please check this is OK. Imaginatorium (talk) 13:50, 25 October 2017 (UTC)

:-) So it seems. I nearly went off on the wrong track in response. No problemo on your edit of my typo. —Quondum 19:46, 25 October 2017 (UTC)

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Convert

a number is a rounding thing. it's on the page. it's not deprecated. read the template page ... Dave Rave (talk) 03:53, 26 December 2017 (UTC)

Let's make sure we're on the same page. Firstly, here are the various displays:

• The speed limit on the full length of the highway is {{convert|110|kph|mph|disp=5|abbr=on}} → 110 km/h (70 mph). (before my edit)
• The speed limit on the full length of the highway is {{convert|110|kph|mph|abbr=on|round=5}} → 110 km/h (70 mph). (after my edit)
• The speed limit on the full length of the highway is {{convert|110|kph|mph|1|abbr=on}} → 110 km/h (68.4 mph). (after your edit)

You appear to be suggesting that the precision in the template output should be increased beyond even the default rounding precision of {{convert}} in the context of speed limits, where IMO such precision is not appropriate. In line with the general observation that mi/h limits appear to occur in multiples of 5 mi/h, round=5 even seems appropriate here. I have been replacing deprecated options of convert with equaivalents, and there are in excess of 1000 articles that use this option with speed limits (mostly associated with road and rail speed limits). See Template_talk:Convert#Let's_drop_the_deprecated_ones for background. —Quondum 04:36, 26 December 2017 (UTC)

Ah, well, you seem to think that what is in your head is obvious to others, though I find your words obscure. My purpose is achieved: removing the deprecated {{convert}} option. —Quondum 14:01, 26 December 2017 (UTC)

History of the metric system overview

I beseech you, kind Sir, to observe the piquancy of the pen. I wrote "But men prefer the familiar though unavailing to the elegant but untested..." and you perambulated, "Adoption of the new system was slowed by the human resistance to change despite its evident advantages...". Pastiche for the masses... (resistance to change): laggardly current in a big choke.

I will share something with you about the pen. Sir Winston Churchill wrote of the death in 1199 of Richard I of England, he who was known as "lion-hearted". He leisurely chronicles the actions of the archer who slayed him, then nary a word about what happened to him in the end. In the encyclopedia, we would write: "The archer was arrested, imprisoned and executed according to law." Very factual and accurate. But Mr. Churchill wrote, in the last line of the chapter, as pithily as possible, "The archer was flayed alive."

You see, history is not about what events transpire, but what they mean. The encyclopedia tells us the events. Churchill tells us what it means to kill the king. Which is the better picture of history? Which are you more likely to remember?

Kind regards, Sbalfour (talk) 22:31, 2 January 2018 (UTC)

Ah, yes. You beseech me to regard the encyclopaedia as a text for persuasion, to permit the mightier-than-the-sword pen to find voice here, while implicitly acknowledging that it is not the right place. I must assume that you are being tongue-in-cheek. —Quondum 00:28, 3 January 2018 (UTC)

'The pen is mightier than the sword' (Edward Bulwer-Lytton, 1839)...sigh; we do not kill with our poison pen, nor write sanskrit with the point of our sword, but pity the soul who fails of pen but is not swift of sword (~ terrible swift sword, Battle Hymn of the Republic, 1862; from Revelations 19:15 "And out of his mouth goeth a sharp sword, that with it he should smite the nations").

I'm having fun now, but writing is fun. And I know my history. Cheers, Sbalfour (talk) 04:06, 3 January 2018 (UTC)

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Exterior Calculus Identities

Hello Quondum! You seem to know something about exterior algebra. I just submitted a draft for exterior calculus identities and I am now surprised about the long review process. I was wondering if you know more about it, if this is normal or not. Wikipedia tells me that it might take more than two months. At this point I just wonder how reliable the review process is. Your name appeared often in the exterior algebra history.

This is my draft: https://en.wikipedia.org/wiki/Draft:Exterior_calculus_identities

Can you share you experience with the review process? By the way I am a phd student at the TU Berlin. Greetings from Berlin.

best wishes

Marcel — Preceding unsigned comment added by Marcel Padilla (talk • contribs) 15:39, 10 September 2018 (UTC)

I have no experience with the review process, and I have to guess what you mean by "reliable". In terms of timing, I would expect "very unreliable" – if you are on a time frame, perhaps your expectations may be a poor match for the way Wikipedia works. In terms of quality of review, I expect that would depend somewhat on who elects to review it and how much editing experience and discipline-specific expertise they have, but in general, I expect a reviewer would make a serious attempt to check the article fairly thoroughly for various encyclopedic factors. I would have to familiarize myself with the criteria and process if I was to review it.

In looking over the article, I could make some comments. It is clearly a WP:list-class article, and as such is not demanding in terms of style. The lead could do with elaboration. Given the title (it is about a topic, not about the sources), you can expect that further editing will add sources: the sources you mention should simply be treated as references; they need not be highlighted. There are some minor editorial points (e.g. no title case for section headings, formatting the unary \star without surrounding space by using braces: {\star}). Premises might be elaborated in some instances. Accuracy seems high, but some things seem odd ("$\alpha \wedge \alpha =0$ for $\mathbb {R}$ valued forms"?). In all, it looks like a useful reference once some issues like this (especially premises or context of validity) are addressed.

What is important to you on this submission? Is this something that is part of your studies? —Quondum 02:32, 11 September 2018 (UTC)

Dear Quondrum,

thank you very much for your quick reply. Yes my question was related to timing. I have been willing to share the page once it is up in an internal blog of our working group.

("$\alpha \wedge \alpha =0$ for $\mathbb {R}$ valued forms"?) You are right. This equation seems out of place. The reason is that I used to think it was always true but apparently quaternion valued forms break this rule.

I will take your comments serious and get better with my sources. My main aim was to make a counterpart to the vector calculus identities article. https://en.wikipedia.org/wiki/Vector_calculus_identities . And I am not sure what WP:list-class article or a lead even means so I will look into this.

with kind regards,

Marcel — Preceding unsigned comment added by Marcel Padilla (talk • contribs) 10:04, 11 September 2018 (UTC)

I have taken the liberty of making some small edits. $\alpha \wedge \alpha =0$ is true only when $\alpha$ is simple, i.e. when $\operatorname {rank} (\alpha )\leq 1$ (trivially for 1-forms, I know for 2-forms, and I suspect for k-forms with k > 2). The identity generalizes to powers, where the exponent is the rank. Yes, I see that it is follows the form of Vector calculus identities closely, and is excellent as a companion article. Don't worry about my comments about the lead (this is not critical) or the list class (this is just a classification which would be applied). I would focus on correctness and ensuring that the premises are explicit, not implied. —Quondum 14:31, 11 September 2018 (UTC)

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WP:UP#COPIES

Re my change to WP:Writing better articles which you reverted, the issue was that WP:User pages was broken such that WP:UP#COPIES redirected to WP:User pages#User pages that look like project pages, which was irrelevant and which is what I saw. I've fixed WP:Writing better articles. Regards, Dan Bloch (talk) 20:20, 22 January 2019 (UTC)

Ah, okay, I missed that it was correct now due to your fix. (I see that your fix was to WP:User pages.) Thanks. —Quondum 20:33, 22 January 2019 (UTC)

Query on Hodge star operator

This is my first time to submit a Wikipedia edit or question, so I may be sending this to the wrong person and I may not have followed all the instructions correctly.

I have two questions relating to the formal definition of Hodge star for k-vectors on web page Hodge star operator § Formal definition for k-vectors.

(1) It seems to me that a definition I propose, below, more directly follows from the Riesz representation theorem argument provided in the article than the current definition. The proposed definition is not equivalent to the current one. I provide an example that shows they are different. (I can provide many examples.)

Proposed definition. Formal definition for k-vectors[edit] The Hodge star operator on a vector space V with an inner product is a linear operator on the exterior algebra of V, mapping k-vectors to (n − k)-vectors where n = dim V, for 0 ≤ k ≤ n. It has the following property, which defines it completely: given a k-vectors β and an (n – k) vector γ,

β ∧ γ = ⟨γ, *β⟩ ω

where ⟨•, •⟩ denotes the inner product on (n – k)-vectors and ω is the preferred unit n-vector.[1]:15

Example: Let n = 2, k = 2, ω = e₁ e₂, β = e₁ e₂, and γ = 1. Then *β is a scalar, and the new definition yields:

e₁ e₂ = β ∧ γ = ⟨γ, *β⟩ ω = ⟨1, *β⟩ e₁ e₂ ⇒ *β = 1

Let α = e₁ e₂. Then the current definition yields:

(*β) e₁ e₂ = α ∧ *β = ⟨α, β⟩ ω = ⟨e₁ e₂, e₁ e₂⟩ ω = -ω = - e₁ e₂ ⇒ *β = -1

So, they are different.

(2) If there is an explicit definition as well, I would think that would be a helpful addition to this article. I believe that there is. For general n and ω = e₁ ... e_n I can show that the proposed definition is equivalent to the explicit definition *β = ω^-1 β whereas the current definition is equivalent to *β = β ω.

matrixbud (talk) 21:50, 4 September 2019 (UTC)

Hi, Matrixbud. I'm not sure there is a "right" person. Editors interact when they are interested. When it relates to content of a specific article and might be of interest to other editors, then the talk page of the article is usually the best place to discuss something, though you might want to ping specific people since they might not be watching that article using {{ping}} or {{u}}. Best is to use the "New section" tab to start a new thread on a talk page (either user or article) so that a section heading is added. In general, you should feel free to ask questions on talk pages until you get the hang of where things belong.

I agree that there seems to be a difference in approach, effectively using different definitions in the same article, and this discrepancy should be corrected. I'm not sure whether one or the other predominates, but the state of the literature on this should ideally be checked first. However, I will note for now that there are four nonequivalent definitions of the Hodge star that are nonetheless interchangeable. Using the notation of geometric algebra for the multiplication, knowing that ω determined uniquely up to a sign with ω⁻¹ = ±ω, the four variants can be written as ωβ, −ωβ, βω and −βω, so there is no fundamentally "correct" one (though under some conditions these collapse into fewer). —Quondum 16:05, 5 September 2019 (UTC)

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Hello,

Google Code-In, Google-organized contest in which the Wikimedia Foundation participates, starts in a few weeks. This contest is about taking high school students into the world of opensource. I'm sending you this message because you recently edited a documentation page at the English Wikipedia.

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Clifford algebra/Quaternions error

Hello Quondum,

I do not want to get involved with editing, but just wanted to point out to you that your recent edit of the Clifford algebra/Quaternions section may be itself incorrect, and that it was actually not in error. Please take another hard look at it, and I think you will see that the original text was actually correct.

In quaternions: i = k/j j = i/k k = j/i or, i = jk j = ki k = ij

The Clifford algebra/Quaternions section gives its formulas with respect to CL(0,3) over R (reals). This means, with elements e1, e2, e3 where e1^2 = e2^2 = e3^2 = -1. The analogy to quaternions in CL(0,3) is: i ~= e3/e2 = -e3*e2 = e2^e3 j ~= e1/e3 = -e1*e3 = e3^e1 k ~= e2/e1 = -e2*e1 = e1^e2 which is how the article (correctly) was before you edited.

If the article were with respect to CL(3,0), then i ~= e3/e2 = e3*e2 = e3^e2 j ~= e1/e3 = e1*e3 = e1^e3 k ~= e2/e1 = e2*e1 = e2^e1 as you have (incorrectly, in this case) edited it.

You can choose to revert yourself, or ignore me. I'm not going to do anything. I'll just leave now by saying that, I am basically an expert in this area of mathematics, and have been published many times in journals on this clifford/geometric algebra and generalized forms of these bivector/versor operators. So, take another look. But, I could be wrong if you can elaborate how. — Preceding unsigned comment added by Twy2008 (talk • contribs) 17:26, 1 December 2019 (UTC)

@Twy2008: Thank you for pointing this out. For some reason, I used the convention where e_i² = +1, and failed to notice that the other convention was in use. Totally idiotic of me. —Quondum 04:56, 2 December 2019 (UTC)

Edits at Physical constant

Hi, I have attempted to express the definitional nature of c, k, e, h on Physical constants more clearly. The uncertainty really is exactly zero. For instance, meters and seconds are defined such that c is equal to 299792458 m/s. c = 299792458 m/s is a tautology. If you were to encounter an apparent contradiction, you would need to calibrate your instrument. Put another way, the uncertainty in c = 299792458 m/s is the same as 12 inches = 1 foot. Can you please review my new edit on Physical constants for clarity? Thanks! Metaquanta (talk) 11:41, 20 January 2020 (UTC)

As far as it goes, it seems accurate, but the question occurs as to what we would be trying to say in the context of this article. My take is that in this context, the change in uncertainties should be addressed, rather than the definitional nature. In contrast, in the SI article, the definitional nature is significant. The SI redefinition had a major impact on the uncertainties of a whole slew of constants when expressed in SI units, a fact that is worth drawing attention to. Some stayed zero (e.g. c), some were nonzero but remained unaffected (e.g. α), some were zero but became nonzero (e.g. ε₀), but in many cases there was just a marked reduction in uncertainty (e.g. m_e). —Quondum 18:17, 20 January 2020 (UTC)

Barn

Wouldn't it be useful to readers to mention that barn was part of SI units for a time, even if it has been removed? That does make it unusual (unique?) on List of humorous units of measurement. I don't have access to the source you seem to have, but I thought I'd mentioned the idea. - DavidWBrooks (talk) 14:01, 27 March 2020 (UTC)

DavidWBrooks, the barn never was part of the SI – and on closer reading of the 8th SI brochure, it never was accepted for use with the SI by the BIPM, so the statement that I removed was incorrect. It was only mentioned as a unit that is used in special interest groups. And no, the barn is not unique in regard to being mentioned – as you'll see from Tables 6–9 in the 8th Brochure, there are several units that are mentioned. The references are publicly available at SI Brochure. Note the Previous editions tab, where you can get the 8th edition and earlier. Though I have no objection to a coherent and correct statement, I can think of nothing of interest to say in this regard in the article. ("Previous SI Brochures mentioned some non-SI units, including the bar, angstrom, barn and knot"?) It doesn't sound to me to be of significance; that it was and still is used as a serious unit seems to overshadow this, and that is still in the article. —Quondum 16:42, 27 March 2020 (UTC)

Fair enough - you're right. Thanks for answering. - DavidWBrooks (talk) 17:24, 27 March 2020 (UTC)

Atomic units

Hi Quondum,

It seems like Ahri6279 https://en.wikipedia.org/wiki/User_talk:Ahri6279

is making a lot of edits to the atomic units page: https://en.wikipedia.org/w/index.php?title=Hartree_atomic_units&action=history

I don't think the Boltzmann constant was ever part of the definition of atomic units, and Ahri is also saying the vacuum permittivity is set to 1, instead of 4\pi\epsilon_0.

Can you help me verify if this information inserted is correct? — Preceding unsigned comment added by 209.122.224.48 (talk) 21:33, 31 March 2020 (UTC)

I've reverted all the revisions involved. Some are apparently without basis ("atomic unit of entropy"?) and some are outright incorrect (such as the change to the definition of a₀), in contradiction of the NIST website (and other sources). —Quondum 01:49, 1 April 2020 (UTC)

Thank you for helping with reverting the edits. I am quite convinced that the redefinition of $\varepsilon _{0}=1$ was incorrect. 209.122.224.48 (talk) 12:20, 1 April 2020 (UTC)

Yup. You just have to look at the CODATA value to see that it differs by a factor. —Quondum 13:27, 1 April 2020 (UTC)

Photon

Thanks for working on the photon page. I'd like to help fixing it further, but having to switch to teaching my classes online has consumed even more time and energy than foreseen, so I don't know how much I'll be able to contribute. XOR'easter (talk) 16:27, 28 April 2020 (UTC)

I'm not much help, unfortunately. The bulk of my edits involve minor copyedits, tiny fixes and occasional fact checks (and giving opinions); I rarely add much that requires research. IMO, Photon is too short on background and flow to have FA status – it comes across as a scattering of technical quantum mechanical perspectives. Someone who is good at shaping the overall structure of the article would be helpful to have for this. —Quondum 18:04, 28 April 2020 (UTC)

international system of units

Hello Quondum, thank you for your contribution. I viewed your suggestion and saw no discussion suggesting we use incorrect English because the source was seen to use incorrect English. "The speed of light in vacuum" is incorrect. "The speed of light in a vacuum" is correct, and it is also commonly used English in contrast to what you have suggested. Placing the "c" beside "speed of light" helps newcomers to see that the "c" refers to the speed of light and not to the vacuum. We wish to make the wikipedia useful for ALL users and that is why I made the initial change to standard English. If you believe I have been mistaken please let me know on my "do better" talk page, perhaps you can explain your point of view. Hoping you find this to be a constructive message. — Preceding unsigned comment added by Do better (talk • contribs) 18:09, 12 May 2020 (UTC)

Vacuum is not an object. Rather it is a state-of-being where there are few, if any, objects. So applying an article ("a" or "the") to "vacuum" would be inappropriate.

"c" does not refer to the local speed of light within whatever medium the light happens to be; rather it refers to the universal speed limit. So it is not an attribute of "light", but rather of "light in vacuum". JRSpriggs (talk) 01:18, 13 May 2020 (UTC)

JRSpriggs, due to the request above ('please let me know on my "do better" talk page'), for my own reply see User talk:Do better. —Quondum 02:00, 13 May 2020 (UTC)

Planck

Planck units, Planck acceleration ... I think I'm more tired of this topic than I've ever been about anything remotely related to physics! XOR'easter (talk) 22:22, 2 June 2020 (UTC)

I understand the feeling. The return on the effort can at times be unrewarding. I've removed those articles from my watchlist to avoid getting triggered; my resilience has not been great (mostly unrelated). I see the banned sock is also still at it. It is a topic that attracts OR. I notice inconsistency in choices made in the references, suggesting that even in academia, the topic is somewhat ad hoc – there seems to be a trend towards rationalized units; maybe soon we'll be seeing 4πG being used in place of G for so-called Planck units. (Perhaps we should call rather them "natural unit systems at the Planck scale"?) Maybe I'll do another cleanup in a year or so; I rationalize it as that WP will survive a bit of nonsense.

FWIW, having your voice in the mix has helped my state of mind during this period. Though I'm not watching, feel free to ping me for specific input if desired. —Quondum 12:40, 3 June 2020 (UTC)

Indulging in a little OR of my own for the moment, a lack of consistency among the (few) references on the topic suggests that it has not been interesting enough to attract the kind of attention that would lead to standardization. XOR'easter (talk) 16:05, 3 June 2020 (UTC)

My speculation is that there is a confluence of factors at work here, such as the Planck scale being only to an order of magnitude where the wheels must fall off, making the choices unimportant, and the tendency to use the shorthand "Planck [...]" for anything related. The former is relates to what you're saying, and the latter gives a ready handle that allows people to think it is more of a thing than it is.

I wish I still had the mental agility and energy to look into things that intrigue me. For example, the following seems provable: "For every k-form on a pseudo-Riemannian manifold, a set of Maxwell's equations apply (obviously generalized), including conservation of two types of charge and of something indistinguishable from energy–momentum." I would expect this to be standard physics, but I never learned this as a mathematical necessity as opposed to a property of our universe. —Quondum 00:13, 4 June 2020 (UTC)

Period

My point was not that WP:LQ should be ignored, but that your edit was entirely contrary to it. The article was right before you started. SpinningSpark 02:33, 9 July 2020 (UTC)

I fail to see your reasoning. I know the period is not in the same place as in the source, which is why I specially mentioned MOS:CONFORM. Do I need to point out that you are not giving reasons for your revert and your comment above, other than that "you are right"? Please motivate why you feel that my references to the MOS are misguided. You will note that I have been at pains to be very specific; at least you should have the courtesy to point out why you believe that those specific points do not apply. —Quondum 13:59, 9 July 2020 (UTC)

Perennial arXiv

Hi there... re this, see the arXiv entry in Wikipedia:Reliable sources/Perennial sources. No big deal, but just a heads up . Cheers - DVdm (talk) 21:20, 12 July 2020 (UTC)

Forgot to mention, see my this, but followed by this. - DVdm (talk) 21:33, 12 July 2020 (UTC)

Yep, I reasoned that it is no worse than no reference for what was already there; I wasn't adding text based on it (I added that text a long time ago to displace another claim that "gravitomagnetism" was a synonym for "gravitoelectromagnetism"). This was the first time I'd seen it directly stated, as opposed to having to infer that claim from usage. The arXiv source does claim to have been published (Unified Field Mechanics: Natural Science Beyond the Veil of Spacetime, Morgan State University, USA, 16–19 November 2014), though I'm unsure that this has any better standing than arXiv (it seems to be a bit fringe from its blurb, and I see no real indication that it is peer-reviewed). It's weird how respected authors such as JA Wheeler use the term without directly defining it or saying that gravitomagnetism is analogous to magnetism (not electromagnetism), even though one can generally infer that this is what they mean from how they use it. —Quondum 23:12, 12 July 2020 (UTC)

Yes. By the way, I did not undo this again because indeed the citation evidence seemed largely sufficient. Cheers. - DVdm (talk) 08:20, 13 July 2020 (UTC)

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"Ring action" listed at Redirects for discussion

A discussion is taking place to address the redirect Ring action. The discussion will occur at Wikipedia:Redirects for discussion/Log/2020 November 24#Ring action until a consensus is reached, and anyone, including you, is welcome to contribute to the discussion. D.Lazard (talk) 17:06, 24 November 2020 (UTC)

Binomial theorem on Ring page

I am not sure if you saw this, but I partially undid a change you made at ring, concerning the binomial theorem. I agree with you that it seems a little out of place, but on the other hand, it is a useful general property of commuting elements in a ring, so I feel that it does belong somewhere on the page, and, like you, I couldn't figure out a better place for it. Maybe you can think of some way of reorganizing things so that it fits better. (Feel free to delete this message after reading.) Ebony Jackson (talk) 20:56, 25 December 2020 (UTC)

You will know better than I about the usefulness of this in the encyclopaedic setting and elsewhere. I would have expected in the noncommutative setting, one would want to phrase it more generally, e.g. as the simplification of a special case of the obvious noncommutative version, or stating it as when the two elements belong to a commutative subrng (which at least addresses my semantics concern). Utility/value considerations aside, what I reacted to is that the encyclopaedic setting related to noncommutative rings, expressions involving multiplication taken from the commutative setting must have the order of the product disambiguated (with the premise, this obviously does not make a difference, but without stating that, it feels like sloppy presentation). I initially toyed with including the parenthetical phrase "as written" to imply that the commutative form is to be reinterpreted as is in the noncommutative setting, but then thought that this seemed like such a narrow edge case that it did not warrant the space in such a general article. This last valuation may be off, but your matrix example still does not strike me as likely to be common. Yes, reorganizing can address it; the structure is not quite right. —Quondum 22:28, 25 December 2020 (UTC)

OK, I understand your thinking better now. Yes, perhaps the "noncommutative binomial theorem" should be mentioned somewhere. Does it exist somewhere on Wikipedia? Probably it does not deserve its own page, but it could appear as a remark somewhere. Maybe at binomial theorem?

Maybe the reason that the noncommutative binomial theorem is not as commonly mentioned is that it is more straightforward, not requiring the determination of any coefficients.

As for the rng version, that is OK as long as you are excluding the exponent 0 case!

The binomial theorem for commuting matrices is useful, I think. It comes up, for example, when finding an explicit formula for the nth power of a complex matrix A: By conjugating, one can assume that A is in Jordan canonical form. If A is diagonal, then one just raises the entries to the nth power. But in general, A = D + N with D diagonal and N nilpotent and DN = ND, so one can use the binomial theorem to compute (D + N)ⁿ, with most of the terms vanishing for large n.

I agree with you that the structure (regarding the placement of the binomial theorem on the ring page) is not quite right, though I don't know what to do about it. Ebony Jackson (talk) 23:30, 25 December 2020 (UTC)

I expect a non-commutative form of the binomial theorem would fit under Binomial theorem § In abstract algebra. I don't feel strongly enough about it, and have never seen it, even though it is simple enough to state (with some purpose-invented notation, I guess). It was just that the context seems to suggest that approach since it is quite pretty. I would not consider putting it in if it is not available in a suitable secondary source.

The rng version needs special treatment of the first and last term for every case, and the n = 0 case must necessarily be excluded. I would say that in a ring the case n = 0 can be problematic. Defining x⁰ ≝ 1 creates a few caveats, even though one can mostly just forget them if every ring as used, and hence its identity element, is clearly defined. It is common to find lack of clarity of this kind, though, especially where complex matrices are concerned. My instinctive approach is to exclude n = 0 and to treat the x⁰ "as if it were 1 in the context". The article says "it is possible to expand any nonnegative power of x + y into a sum of the form ...", which I think is pushing it: it should be strictly positive powers.

I take your point that there are useful general instances of commuting elements that might arise naturally. My intuition was that two "different" matrices would be effectively randomly selected, but I should know better.

I made the "properties" subsection in the Ring article more obviously informal. If necessary, one can take the more "basic" properties and create a more formal section for them.

I trust your feelings on this more than I do mine, and I find your way of thinking and expressing things has an appealing clarity. So when you choose to reshape what I have changed, I have no objection; it is just more efficient to make a change and get it beaten up than to debate it first. —Quondum 01:05, 26 December 2020 (UTC)

Thank you for the generous words! Giving the properties section a more informal heading is good.

As for the n = 0 case of the binomial theorem: Even when $n\geq 1$, the formula $(x+y)^{n}=\sum _{k=0}^{n}{\binom {n}{k}}x^{n-k}y^{k}$ requires $x^{0}=1$ and $y^{0}=1$ on the right side, so one might as well use it when needed on the left side too, and then the formula is correct for all nonnegative integers n. My opinion is that in more complicated calculations (e.g., when proving $e^{x+y}=e^{x}e^{y}$ via power series), it would be annoying to have to separate out the first and last term every time one wanted to use the binomial theorem, and annoying not to be allowed to use the exponent 0 case in the binomial theorem - it just would make proofs longer, with more cases, for no good reason! Ebony Jackson (talk) 01:54, 26 December 2020 (UTC)

I did say, "treat the x⁰ "as if it were 1 in the context" – which gives the economy you want.

Perhaps we should identify the culprit in this: the notation a^b means many things, and we rarely make clear a priori which variant we are dealing with, but instead behave as though there is one universal exponentiation function that naturally generalizes to all the uses we put it to. If we preface the binomial theorem with "By the notation xⁿ in the ring R, we mean the product of 1_R and n ≥ 0 copies of x", it all falls into place. There are contexts where this interpretation is inconvenient, and an incompatible version might be more suited. In particular, given x, it might not be clear what containing ring R is the correct one, and hence which "1_R" to use. —Quondum 18:29, 26 December 2020 (UTC)

OK, I understand your point. I guess it is a question of whether one feels that it goes without saying that when exponents are nonnegative integers, x⁰ is always 1. I guess I've never seen anyone argue that there is an advantage in this context to defining it otherwise or leaving it undefined. Ebony Jackson (talk) 23:19, 26 December 2020 (UTC)

By "this context", I take it you mean ring theory. In this context, I am arguing that special care is necessitated – more than is usually communicated (other contexts can be far more pathological).

⇒ A more concrete example of how this might be confusing: Consider a matrix representation of an algebra A = B ⊕ C, a direct sum of two associative R-algebras. ⁰ in this unified representation is different values (matrices) is this representation, depending on a choice that is not captured at any point of the notation. Naïvely, one might even just use the identity matrix, which would be wrong. 0 is in effect an element that is shared by all the direct summands and the direct sum. Thus, in this representation, we need to distinguish between the exponentiation functions A × Z_≥0 → A, B × Z_≥0 → B and C × Z_≥0 → C (one cannot just treat the first two as restrictions of the third) if we include the case n = 0. I consider this to be a sort of fragility in the way it has been set up, prompting special care. It is interesting to note that the closely related function xⁿ − 1 does not have this problem: for n = 0 it is well-defined in any rng without reference to the extent of the containing rng.

⇒ Another example: consider xⁿ in a finite field of characteristic p. In some applications, we are interested in the periodicity p − 1 of the exponent, and would like to work with equivalence classes rather than integers. In this case, we need to define 0⁰ ≝ 0.

—Quondum 03:18, 27 December 2020 (UTC)

1. One could also start with a ring A, choose a subset B, and define a ring structure on B that has nothing to do with the ring structure on A. Then for b in B it could be true that b² computed in A and in B are different. Does that mean that we should not define the square of an element of a ring? I would argue that your first example is like this, arising only because you are using a ring structure on B and C that is incompatible with the ring structure of A (they are not subrings). Ebony Jackson (talk) 05:32, 27 December 2020 (UTC)

2. Yes, you are right that to make 0ⁿ periodic in n with period p-1 starting with n=0, you would have to define 0⁰ = 0, but I think you would have a hard time finding any reputable source that even considers defining it this way. Does anyone really want the polynomial $x^{p-1}-x^{0}$ of degree $p-1$ to have p distinct zeros? Ebony Jackson (talk) 05:32, 27 December 2020 (UTC)

I hope you do not object to my excursions here: I am finding this fascinating as an intellectual exploration, but you should feel free to drop the discussion if you find it to be an imposition.

1: This sounds like an argument against direct sums and products as being considered fundamental operations in ring theory, something that has been bugging me for ages. What is this construction thought of in this context? As a sort of "span of ideals"? The picture that comes to mind is a reverse of the decomposition of a ring using two-sided idempotents, where each of the rings is formally multiplied by one of a set of assumed mutually orthogonal central idempotents of the final ring before summing.

2: To speak of evaluation of polynomials does not seem to fit here. x^p and x¹ over a field of characteristic p are unequal as polynomials but equal as evaluated functions, as I understand it. Even in the context of evaluation of polynomials (which is needed for finding roots), the argument is spurious: there is no need to conflate the xⁿ in the context of a polynomial with the similarly denoted function where the periodicity is to be exploited. On the other hand, I'll be happy to shoot down my own example on the grounds that it seems to lie outside ring theory (and hence as violating the premise of the accepted context) and to lie in rng theory: this structure reflects the behaviour of "group inverses"; that the field has a 1 in this context is incidental. I have seen several papers on this and it seems to be a reputable topic. Notation varies: I have seen x⁻¹ but more often x^# to denote the group inverse; I've not seen anything denoting a general element in the sequence ..., (x^#)², x^#, x^#x, x, x², ... (a cyclic group, so the usual notation xⁿ from group theory could be tempting), since this was not the focus of these papers. An element does not necessarily have a group inverse, but if it exists it is unique regardless of rng embedding. —Quondum 18:03, 27 December 2020 (UTC)

Pretty soon in the source of your talk page, the most common symbol is going to be :! Anyway, direct products of rings are fine, but direct sums are not. The difference is that a direct product is an object that has projection morphisms to the component objects, whereas a direct sum receives inclusion morphisms from its component objects. For vector spaces and more generally modules, finite direct products and finite direct sums coincide, since one has homomorphisms in both directions. Some people get confused and say that this is OK for rings too, but it is not when using the convention that rings are unital, because the inclusion morphisms are usually not unital homomorphisms. Usually when someone speaks of a direct sum of rings, they should be saying direct product of rings. Ebony Jackson (talk) 19:12, 27 December 2020 (UTC)

I was waiting for the {{od}} to line up without an explicit indentation count, which coincidentally is now. Thanks – that supports my intuition on direct sums (I just regarded the direct product as a sort tweaked direct sum). I will need to brush up on the morphisms you mention: these are new terms to me. —Quondum 19:45, 27 December 2020 (UTC)

Surprised you haven't seen this

Surprised you haven't commented on this discussion yet, but it could probably use your input. Primefac (talk) 13:43, 18 February 2021 (UTC)

I removed everything but my user pages from my watchlist, and so did not see it, though I still tend to briefly watch most of what I've edited. I found that I was being too reactive (and not enjoying the energy needed to deal with non-cooperative editors through the usual processes), and so have limited my exposure to WP. I don't object to being pinged, though. I'll also watch that page until the discussion seems to resolve. —Quondum 15:33, 18 February 2021 (UTC)

Totally reasonable, with 7k pages on my watchlist I sometimes feel a little overwhelmed by all the edits... I might not go quite as drastic as removing everything but I definitely think a serious pruning is in order. Primefac (talk) 16:27, 18 February 2021 (UTC)

In my case a persistently difficult editor had managed to slide through a couple of ANIs before because through an argue-until-blue-in-the-face approach and didn't get closed, and I had no appetite for launching another. I felt that the WP was not up to managing this type of problem and had to take a break. So I am effectively as my user page says: no longer active. I use WP for reference and compulsively fix format and other minor bits that I stumble over in articles that I read, but that is about it. —Quondum 17:22, 18 February 2021 (UTC)

I have articles added to my watch-list automatically when I edit them. But I prune it periodically to keep it down to about 250 articles. I also remove any which are the subject of persistent edit warring. JRSpriggs (talk) 22:31, 18 February 2021 (UTC)

Heh – yes, JRSpriggs, I think I should do much the same, if I start keeping an eye on articles again, especially the "remove any which are the subject of persistent edit warring": just leaving article be where I experience difficulty. The thing is to do so early, not once it has gone some way, since by then I have been aggravated. —Quondum 23:18, 18 February 2021 (UTC)

Short descriptions

Howdy hello! Just wanted to let you know I undid your short description change on Planck length, as per Wikipedia:SDFORMAT, short descriptions should aim to be 40 characters or so, and not much longer. Anything longer than about 40 characters won't be visible for most readers. CaptainEek ^{Edits Ho Cap'n!}⚓ 02:48, 1 May 2021 (UTC)

Ah, that is very useful information. Thanks for letting me know. —Quondum 02:55, 1 May 2021 (UTC)

QI: plausibility

XOR'easter, I'm posting this here as it is rambling stuff that would just be clutter on your talk page. I guess that I'm seeing a phenomenon of "This is so bad, if you don't immediately get it you do not deserve to be enlightened", and hence the lack any mention anywhere. Yet, much energy is being spent dancing around this elephant in the room.

• One unmentioned aspect of QI is that it assumes conventional transmission of force via (Unruh) EM fields – that is, the momentum and mass of photons, and in particular, the impulse imparted by a photon are relied on for the explanation of the reaction force experienced when accelerating a body. This means that any momentum imparted to a body is actually carried away by the electromagnetic field in the QI model. This translates into a minimum "power asymmetry" P_min per unit force of P_min = cF (the minimum being achieved by a laser beam reflected perpendicularly from a mirror, where this power is the sum of the incident and reflected power). So 1 N accelerating a body implies P_min = 0.3 GW. This imbalance is supposedly at ultralow frequencies, and we would easily see this as a powerful static EM field being distorted by an accelerating body. Since QI relies on this conventional interpretation, it cannot explain it away as an unseen "dark field".
• Another is when one looks at the prediction of force in McCulloch (2016), one finds a formula that predicts an inertial mass that is inversely proportional to the depth of the body in the direction of acceleration, and McCulloch arbitrarily injects the Planck length here to obtain precise predictions. Why precisely the Planck length? Not explained: it seems arbitrarily used, as though the result should not depend on the choice. Yet, any other depth gives a very different mass, down to almost nothing at say the size of a proton. So now we need an explanation of why fundamental particles are "really" of one Plank length in size.

I am saying these things because no-one seems to be saying them. It seems that there is a sort of collusion of silence between the insightful and the incompetent. Interesting sociological phenomenon. —Quondum 12:37, 4 June 2021 (UTC)

It wouldn't be the first time that the physics community found an idea so uninteresting they never bothered to criticize it, so all sorts of errors and arbitrary choices didn't get explicitly pointed out. XOR'easter (talk) 15:09, 4 June 2021 (UTC)

I suppose we need to be more brutally explicit on the talk page. I guess I'll be the one to to do so. —Quondum 15:29, 4 June 2021 (UTC)

"It wouldn't be the first time that the physics community found an idea so uninteresting they never bothered to criticize it, so all sorts of errors and arbitrary choices didn't get explicitly pointed out." quoting XOR'easter above

but then decent scientific journals and referees would totally stop accepting papers about it? But even recently there are new papers about this in very decent journals. XOR'easter clearly show his prejudice. And I do not say QI will end up being right or wrong. It is a theory that still is under discussion, it is still funded by DARPA. But XOR'easter and Quondum know best and can play gods! ChrisCalif (talk) 17:38, 6 June 2021 (UTC)

Quondum is clearly violating the NPOV rules

Quondum is clearly violating the NPOV rule: "every time I try to read a paper by McCulloch I am freshly appalled. [...] it needs to fit the reality: QI is horribly audacious pseudoscience, so we can't present it in a way that it could be perceived as believable. —Quondum 21:46, 4 June 21

This is why it is highly relevant to point out that QI has like 20 peer reviewed published papers in scientific journals. Most of these journals have very good quality standard according to almost any national scientific physics boards, with a few exceptions. There is about one or two critical paper published in a good journal, and one of these papers partly post constructive critics.

This is clear proof that Quondum is violating NPOV rules, he should be considered banned from editing. ? Or is Quondum's evidence for that QI is pseudoscience a blog, or is it something he heard on instagram? He should explain, or be blocked! ChrisCalif (talk) 17:27, 6 June 2021 (UTC)

ChrisCalif, from your posts here and at Talk:Quantized inertia, you appear to be highly vested in the article Quantized inertia. Because of your accusing approach, I am not particularly interested in even guiding you into more constructive engagement. —Quondum 18:22, 6 June 2021 (UTC)

you are the one violating wikipedia rules, of ignoring totally to try to be neutral. I am just pointing out exactly what you are doing. ChrisCalif (talk) 18:27, 6 June 2021 (UTC)

" you appear to be highly vested in the article Quantized inertia."

Not at all, I have nothing to do with this theory. I removed one word from the page "pseudoscience" as there seems to be no backing for this claim, but this claim fits well with your prejudice I see. I am curious about this and many other theories that is all. Please do not accuse also me for anything you not can back up! I simply do not like to see the very unfair treatment you are giving this theory. I will look also more into your editing on other pages. ChrisCalif (talk) 18:29, 6 June 2021 (UTC)

Edit summary

Your edit summary here concerns me, as it implies I "overstepped" WP:3RR. In the future, please use more care before submitting edits with an edit summary that is clearly false. This goes back to my earlier edit summary about finding editors who can read. —Locke Cole • t • c 18:00, 21 June 2021 (UTC)

Do you not count four reverts by you on that page in a 24-hour period? The topic is already on the talk page with your involvement (and hence even the first of the four counts as a revert). In parallel you made three reverts in parallel at Template:Quantities_of_bits, which is closely related material, which does not help your case. —Quondum 18:20, 21 June 2021 (UTC)

Just like you guys misread the JEDEC source that you use to claim the terms are "deprecated", you misread my edits as well. There are only three reverts, with one edit to add a {{who}} since it was initially unclear who was deprecating the terms. —Locke Cole • t • c 19:01, 21 June 2021 (UTC)

Absolute hot

I've added more sources in the talk page. I'm not sure what information is needed at this point to hold off the deletion process. Remember (talk) 09:42, 23 June 2021 (UTC)

I have replied on the article's talk page; I think that the explanation of the options and process should be clear enough. —Quondum 12:02, 23 June 2021 (UTC)

Thank you! Remember (talk) 13:18, 23 June 2021 (UTC)

Re ping

@Dondervogel 2: The editor making waves on the issue that you pinged me about is the proximate reason that I had my account blocked, but they are not the only one. The bigger-picture reason is that I can't function in an environment (WP) that permits that level of toxicity. If it comes to an administrative action, I might consider having my account unblocked. —Quondum 20:36, 24 September 2022 (UTC)

I've only just noticed your post (I did not receive notification). I did post this note at ANI. Last updated (I think) on 25 Sep 2022 Dondervogel 2 (talk) 10:29, 28 September 2022 (UTC)

Unblock rq

El C, could you unblock me? The user that frustrated me so much that I quit WP is (again) being taken to ANI (see link left in the thread above), so maybe I should join to add my perspective there. Not that I expect much: I am pretty disillusioned about the lack of management of harassment and abusiveness on WP, as in these cases admins rarely block the offender even temporarily, but just leaving others to cope with harassment also does not seem right. —Quondum 12:26, 28 September 2022 (UTC)

This user's unblock request has been reviewed by an administrator, who accepted the request.

Quondum (block log • active blocks • global blocks • contribs • deleted contribs • filter log • creation log • change block settings • unblock • checkuser (log))

---

Request reason:

As per above: I've just discovered this template. This was a self-requested block. —Quondum 12:29, 28 September 2022 (UTC)

Accept reason:

Good to have you back. El_C 14:41, 28 September 2022 (UTC)

October 2022

Hello, I'm Locke Cole. I noticed that you added or changed content in an article, NTFS, but you didn't provide a reliable source. It's been removed and archived in the page history for now, but if you'd like to include a citation and re-add it, please do so. You can have a look at referencing for beginners. If you think I made a mistake, you can leave me a message on my talk page. Thank you. —Locke Cole • t • c 16:09, 8 October 2022 (UTC)

As you might have discerned from my edit comment, my concern was the hodgepodge mix of prefixes, which was a problem regardless of sourcing. There were two options for making it consistent. Your way needed the disambiguating footnote, such as you added, so that is fine with me. Given the context (NTFS, Microsoft), your approach might feel more natural to many. I am perfectly happy either way: the hodgepodge mess is gone. —Quondum 21:13, 8 October 2022 (UTC)

Ronna

Is there still a history page for my ronna article? Even if it stays deleted I want to reference it. WalkingRadiance (talk) 02:29, 7 December 2022 (UTC)

WalkingRadiance, the history for the Ronna- page is at https://en.wikipedia.org/w/index.php?title=Ronna-&action=history, and you can access the specific version as it was after your last edit at https://en.wikipedia.org/w/index.php?title=Ronna-&oldid=1125970532. You will also able to retrieve any page that you edited (as it was) from your own contributions at Special:Contributions/WalkingRadiance, which you can access from the top of any WP page generally. I hope this is what you were asking. —Quondum 02:43, 7 December 2022 (UTC)

AN/I

There is currently a discussion at Wikipedia:Administrators' noticeboard/Incidents regarding an issue with which you may have been involved. Thank you. —Locke Cole • t • c 00:15, 17 December 2022 (UTC)

overlines using combining unicode characters vs. overline template

I found the result of your change to be uglier than the previous version. Can you explain what the issue is with the Unicode combining overlines? In my opinion the overline template renders a line far too high and is not really generally suitable for indicating the complex conjugate. If the overline glyphs are giving trouble for the article body I’d recommend just replacing all of the math formulas with LaTeX, but that doesn’t work for image captions. –jacobolus (t) 03:59, 18 February 2023 (UTC)

On my browser, it does not combine properly, but renders after the character: something like "z  ". Given that my browser is mainstream (Mozilla Firefox) on a common OS (Ubuntu), this is likely fairly common. I have not checked whether this is the font set or something else. Perhaps the LaTeX would a better option. At least that would reduce the problem to one image caption. —Quondum 04:07, 18 February 2023 (UTC)

How does z̅ render in your browser? –jacobolus (t) 04:28, 18 February 2023 (UTC)

Still the same problem: the bar is displaced to the right so that it half over the 'z' and fully over the space that follows it. A little experimentation shows that it only happens when inside when using the math template, though: {{math|''z''}}̅ renders perfectly for me (z̅), i.e., with the combining character immediately outside the math template. —Quondum 12:47, 18 February 2023 (UTC)

That version breaks in everyone else’s browser. :-)

This issue seems like a Linux Firefox bug. Perhaps the font you are using for "math" (the CSS asks for "Nimbus Roman No9 L","Times New Roman",Times,serif) does not include a combining overline glyph? –jacobolus (t) 15:58, 18 February 2023 (UTC)

Oh, dear. The horizontal offset problem does not manifest for the default font (''z̅'' z̅ or ''z''̅ z̅, with the former being visually better aligned with the top of the 'z' for me), so another solution might be to remove the math template. —Quondum 16:20, 18 February 2023 (UTC) I am using only fonts "installed with the system": no changes, with all settings left as the default.

I just checked with Safari on macOS and iOS. Scratch my second option, and I agree that what I proposed and that {{math|''z''}}̅ is broken. So if we are to stay with HTML, ''z̅'' is the only (hopefully) unbroken one, with {{math|''z̅''}} as the least broken alternative if the serif font is a must. —Quondum 16:36, 18 February 2023 (UTC)

Thank you!

Thanks for handling the merge of Angle and Angle of rotation! Joyous! | Talk 02:57, 23 February 2023 (UTC)

Joyous!, thank you for fixing my oversight :) —Quondum 04:18, 23 February 2023 (UTC)

Your hate against the Coulomb constant

On 8th March you have proposed to merge the Coulomb constant page with the Vacuum permittivity page. After that, while not waiting for feedback from the community, you have started to edit several articles with the sole purpose of removing all mentions of the Coulomb constant from the entire encyclopedia (I have counted nine: #1, #2, #3, #4, #5, #6, #7, #8, #9).

Two are the things that leave me wonder, but the second one is way more important than the first. The first one is why you hate the Coulomb constant to the point of preferring to rewrite something as simple and beautiful as

$F=k_{\text{e}}{\frac {q_{\text{1}}q_{\text{2}}}{r^{2}}}$

into something as ugly, artificial and byzantine as

$F={\frac {1}{4\pi \varepsilon _{0}}}{\frac {q_{\text{1}}q_{\text{2}}}{r^{2}}}$

– and this despite the obvious gravitational analogy

$F=G{\frac {m_{\text{1}}m_{\text{2}}}{r^{2}}}$

Even just didactically speaking you are not really doing a favour to this encyclopedia. But besides your odd personal tastes – which you may not be willing to explain to me, or you might try but I probably won't understand them – the second point is actually quite important and I believe an answer is due: What makes you feel entitled to think that such a massive intervention on several pages is the right thing to do in absence of any feedback or second opinions from the community? (I am obviously waiting for XOR'easter showing up in your support at this point). -- Grufo (talk) 10:52, 12 March 2023 (UTC)

You open with what amounts to a personal attack, describing me in terms that are based on your presumptions about me. You then proceed to make a mistaken connection based on presumption without prior enquiry. This is not a way to open a rational discussion on anything. You then make what may be intended as a snide reference to another editor without alerting them (though I'm not sure what that editor's relevance is in this at all). Please review acceptable behaviour on Wikipedia and in particular on user talk pages. —Quondum 14:43, 12 March 2023 (UTC)

Reduced Compton wavelength

At least consistent but not conventional (is there a convention?) Xxanthippe (talk) 23:57, 30 March 2023 (UTC).

I'm no expert, but it seems common to use lambda to denote a wavelength (and not a "radian-length", if I may coin a term for clarity). It also seems to be conventional to use a character with a stroke for "reduced" quantities (the radian-equivalent of a cycle-related quantity) in general. In particular, λ_c usually denotes the Compton wavelength, and so a distinguishing notation is needed, so using something other than λ_c is appropriate. Examples of use of the the barred lambda for the reduced Compton wavelength: [3], [4] (warning: the second link loads a very big PDF, and may be slow). I don't recollect ever seeing another symbol for it; only the subscript varies. If you want a more solid opinion, WT:PHYS is probably the place for it. —Quondum 02:26, 31 March 2023 (UTC)

Disambiguation link notification for May 5

An automated process has detected that when you recently edited Spatial frequency, you added a link pointing to the disambiguation page Cycle (unit).

(Opt-out instructions.) --DPL bot (talk) 07:26, 5 May 2023 (UTC)

Links to user pages and sandboxes

Please do not introduce links in actual articles to user pages or sandboxes, as you did at DESY. Since these pages have not been accepted as articles, user pages, sandboxes and drafts are not suitable for linking in articles. and such links are contrary to the Manual of Style. These links have been deleted, please do not re-add any such links, thank you - Arjayay (talk) 18:30, 25 June 2023 (UTC)

Apologies: that was unintentional. My cleanup prior to and after a series of moves and revisions was incomplete. But thanks for catching that. I have made further changes after yours to what they should be. —Quondum 18:44, 25 June 2023 (UTC)

E=p²/2m

You wrote "the equation E=p²/2m has no basis, and deriving results without a source for those results is not permitted." and "please do not be dogmatic about something you evidently do not understand sufficiently"

If you don't know that E=p²/2m is one of the fundamental equations of physics, this means that you know nothing about physics. So don't write about things you don't understand completely.

TD (talk) 13:49, 12 August 2023 (UTC)

If you wish to seriously contribute to WP, firstly, your tone will need to change considerably. I understand the Newtonian equation relating kinetic energy to momentum. I also understand the equation of special relativity, which relates the total relativistic energy to the rest mass of a particle and its momentum. You seem to be insisting on considering these to be the same quantity, which they are clearly not.

It is not the role of any other editor to educate you about the subject matter that you choose to edit, but it is permissible to remove erroneous material, such as you included. I tend to be patient with those who are willing to consider that they may have made an error and are willing to engage in polite discourse. I, of course, may make errors as well, but your aggressive, insulting tone has the effect that constructive engagement with you is not likely to happen. —Quondum 14:15, 12 August 2023 (UTC)

I do not confuse relativistic and non-relativistic physics (which it seems you don't know). You were the first to be very impolite.TD (talk) 14:19, 12 August 2023 (UTC)

CS1 error on Buckingham (unit)

Hello, I'm Qwerfjkl (bot). I have automatically detected that this edit performed by you, on the page Buckingham (unit), may have introduced referencing errors. They are as follows:

• A "missing title" error. References show this error when they do not have a title. Please edit the article to add the appropriate title parameter to the reference. (Fix | Ask for help)

Please check this page and fix the errors highlighted. If you think this is a false positive, you can report it to my operator. Thanks, Qwerfjkl (bot) (talk) 12:39, 17 October 2023 (UTC)

Thanks, bot, good to see you spotting such things. In this instance, I converted an existing reference to using a citation template, the title was already missing, and I decided to leave the visible flagging of the omission of title there for later repair by anyone who can figure out what the title of the article is. I did not succeed in finding an online copy of the reference to be able to do so. —Quondum 16:49, 17 October 2023 (UTC)

Boolean ring (math formatting)

Hi Quondum. I see that you recently did some formatting changes to Boolean ring. User Cedar101 had previously changed a few things, but it was really not optimal. You have followed suit using his style. For information, you can see the comment I made here: https://en.wikipedia.org/wiki/User_talk:Cedar101#Your_changes_to_Boolean_ring_(math_formatting)

Would be interested to know if you have any opinion on that.

Regards. PatrickR2 (talk) 23:31, 23 October 2023 (UTC)

Good article reassessment for International System of Units

International System of Units has been nominated for a good article reassessment. If you are interested in the discussion, please participate by adding your comments to the reassessment page. If concerns are not addressed during the review period, the good article status may be removed from the article. ~~ AirshipJungleman29 (talk) 22:36, 20 November 2023 (UTC)

Undefined sfn references in Geometric algebra

Hi, you've just added sfn references to "Lounesto 2001" but no such work is listed. This means that nobody can look the references up, and the article is added to Category:Harv and Sfn no-target errors. If you could supply the missing source it would be appreciated. DuncanHill (talk) 00:58, 3 March 2024 (UTC)