Feedback request: Maths, science, and technology request for comment
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I moved your comment to the Ideal Gas talk page and responded there. But if you are sure that you are correct then remove or better clarify my comment for both ideal gas and the ideal gas law. Thanks. Tuntable (talk) 09:58, 30 June 2020 (UTC)[reply]
I saw your sandbox essay. Here's the thing: I was advised a long time ago to make as minimal a fuss as possible when reverting trolls. Hence the edit summaries of "wp:deny" and nothing else. Any more than that does nothing but feed the trolls. ←Baseball BugsWhat's up, Doc?carrots→ 20:36, 24 August 2020 (UTC)[reply]
I can understand your frustration Dolphin51, it's a shame that the contributions of those editors were deleted. The troll was obvious though and it was necessary to remove the post, so as to deny the troll any more attention. No one is to blame but the troll. I hope you can see it for what it is. That RfC about medical advice is a separate matter. Regards, Zindor (talk) 22:10, 24 August 2020 (UTC)[reply]
Are you sure that you have to do another five hour flight? I have never heard of this, despite being an Official Observer for many years. I was certainly awarded my Gold Badge without have to do another one. There was a case of someone, who had flown both the 300km and made 3000 metre gain, not being awarded the Gold Badge until a five hour flight had been done. But only one flight was needed. JMcC (talk) 09:44, 8 October 2020 (UTC)[reply]
Thanks for drawing that to my attention. I included the word "another" as part of my interpretation of the requirement. I was relying on Reference No. 53 and it doesn't imply that a second 5-hour flight is required. I have amended the article to eliminate my error. Dolphin(t)12:14, 8 October 2020 (UTC)[reply]
Xingu River
I do not understand the full revert. The removed information is relatively unimportant but can certainly be kept if anyone wants it. The problem is the description section which seems to be a major improvement. Is there any reason that the description section should not be upgraded? Benjamin Trovato (talk) 06:31, 11 October 2020 (UTC)[reply]
Hello @Benjamin Trovato: I assume you are referring to the revert made in this edit: diff. That edit was made by User:Dl2000, not by me.
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It is my pleasure. Don't forget I'm always available to help you navigate your way around Wikipedia; no question is too dumb. And thank you for the barnstar! Dolphin(t)01:29, 11 December 2020 (UTC)[reply]
Merry Christmas!!!
Hi Dolphin51! I just wanted to thank you again for all you do here. I wish you a very Merry Christmas, or whatever holiday you celebrate, and may the coming year bring you much happiness and joy. May it at least be better than this one. Merry Christmas and Happy New Year! Zaereth (talk) 00:26, 24 December 2020 (UTC)[reply]
Hi, I saw your comment on Tony's page. It will be interesting to see what he says. I think "that" is almost always redundant in the context of "he saw that" "she said that" "she thought that". Graham Beards (talk) 10:34, 12 March 2021 (UTC)[reply]
Thanks Graham. I agree it will be very interesting to read Tony’s thoughts. I appreciate your message, and your support. It is always encouraging to discover that we aren’t the only User to hold a particular view! Dolphin(t)10:46, 12 March 2021 (UTC)[reply]
You know, I saw this and it grabbed my interest too, because linguistics (and in particular the history of English) is an interest of mine. At first I thought you were talking about "that that", which is a personal pet peeve of mine, as you can see here. That's one that is truly redundant in nearly all cases.
I too was interested in what Tony would say, because he's a lot smarter than I am in this area. Turns out, it was basically what I was thinking too, in that, when used in that way it's a conjunction indicating a subordinate clause. There may be instances where it's unnecessary, but you have to look very carefully at how removing it affects the meaning of the sentence. Sometimes it's just idiomatic, but sometimes it is used to distinguish between the clause as part of the sentence and a different meaning it takes on when separated from the sentence. Sometimes an alternative is to replace the "that" with a comma, and that can sometimes work. You just have to watch carefully for those dual meanings that can crop up. The same thing can occur with other conjunctions, adverbs and adjectives. "In order" (as in "in order to") is a good example. Most of the time it's not necessary, but there are occasions where it is very much is. Anyhow, sorry to ramble, but maybe something in there might help. Zaereth (talk) 01:10, 13 March 2021 (UTC)[reply]
Thanks Zaereth, I appreciate your message. Tony has replied and it has given me a new insight into the problem. My most recent erasure of a redundant “that” was about 4 days ago to the article Jeremy Corbyn. Let me know what you think of it. (Sorry I can’t post the diff; I am presently relying on an iPad and I don’t know how to harvest diffs on an iPad.) Dolphin(t)02:06, 13 March 2021 (UTC)[reply]
Hi Dolphin51. I saw this edit you made here. Just for reference, the link syntax [[:User:XXX]] works similarly to user notification templates per WP:PING; so, there was really no need to make the change you made. Whether the IP realized this when they made that particular post is unknown, but the "ping" probably still worked. In addition, converting the syntax to the {{u}} template the way you did wouldn't have had the desired result because the "ping" syntax needs to be added with a signed post in the same edit per H:PINGFIX in order for the software to know it's supposed to ping someone. Finally, while I do understand the reasons for making such a change, there are cases where an editor might be mentioned in a post but has intentionally not been pinged by the person doing the posting for whatever reason. So, maybe in such cases involving posts made by others, it would be better to use either a {{Please see}} template to inform someone that they've been mentioned or simply post a new post pinging them that you can sign if you feel they should be notified. -- Marchjuly (talk) 23:27, 3 May 2021 (UTC)[reply]
Hi. Thank you for your recent edits. An automated process has detected that when you recently edited Portmoak, you added a link pointing to the disambiguation page Loch Leven. Such links are usually incorrect, since a disambiguation page is merely a list of unrelated topics with similar titles. (Read the FAQ • Join us at the DPL WikiProject.)
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Hi Dolphin51! I just wanted to say thanks for all you do for Wikipedia, in science, fluid dynamics, and energy-related articles especially. I hope you have a wonderful holiday season, and may the coming year bring you great joy and good fortune. And, if you don't celebrate Christmas, then please take it as a Happy Hanukkah, a great Dhanu Sankranti, a blessed Hatsumode, or whatever holiday you want to insert there. Zaereth (talk) 23:26, 24 December 2021 (UTC)[reply]
I saw your edit on the slip article, and I agree is should be removed. What I think the author was trying to describe there was crabbing, which is not correcting a course with a slip, but rather using a slip at the last second to align the plane with the runway. For example, when you land on an aircraft carrier, not only is the carrier still moving forward, plus rocking and pitching, the runway is at an angle to the line of approach and glide slope, so you have to crab the aircraft to line it up with the landing strip just before touchdown. Aside from fighter planes, this is something all aircraft have to do while landing in a crosswind. I think the article could probably benefit by describing crabbing. Perhaps when I have more time I'll work on that ... with far better sources that youtube of course Zaereth (talk) 21:32, 11 April 2022 (UTC)[reply]
Thanks Zaereth. You say “this is something all aircraft have to do while landing in a crosswind.” I would agree if you change that to “all aircraft have to do when touching down in a crosswind.”
During the approach to land in a crosswind, the aircraft can be in balanced flight so the pilot sees the bubble in the centre of the balance indicator, although the runway will be slightly to the left or right of the aircraft centreline. If the pilot is to avoid scrubbing the main wheels on touchdown it is necessary to use the rudder to “straighten up” moments before touch down; or crossing rudder and ailerons to align the centreline of the aircraft with the runway by slipping or crabbing sideways in the seconds before touch down. Dolphin(t)22:17, 11 April 2022 (UTC)[reply]
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Apologies if this isn't the right place for this. If so do please let me know, I find the navigation very confusing.
You reverted an edit which I made, saying that what I described was only a thought experiment.
No problem if I've violated the requirements but I'd have to take issue with "thought experiment". I did this personally in a physics lesson on the playing fields at Swanwick Hall Grammar School in 1964 when I was eleven years old. Perhaps I should find the physics textbook in use by the school at that time to give as a reference? However after almost 60 years I can't even be sure that the method is described in it. :)
Jamesmcardle Thanks for raising the matter on my Talk page. Guidance is provided at MOS:SEEALSO which implies that a blue link to another page qualifies for inclusion at “See also” if it is clearly relevant to the article, or a sound argument can be made that it is relevant. I don’t think “vorticism” is clearly relevant to fluid dynamics and therefore you should explicitly provide your sound argument as to why you think it is relevant. You could make your case at Talk:Vortex so that other Users interested in fluid dynamics can see your ideas, comment and put forward their own ideas.
If a reader is using Wikipedia as a dictionary and looking for words similar to “vortex”, that reader might end up looking at the “See also” section in Vortex. However, Wikipedia is not a dictionary. If a reader is using Wikipedia correctly, that reader will be reading Vortex to obtain information about fluid dynamics and the science behind the physical phenomenon known as a vortex. That reader is unlikely to be looking for Wikipedia’s articles about art and artistic movements, but I could be wrong. Dolphin(t)13:44, 27 October 2022 (UTC)[reply]
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Hi Dolphin51. I just wanted to take this time to say thanks for all you do around here. I hope you're doing well on this cold winter's day. I wish you and yours a very Merry Christmas, and a Happy New Year. Zaereth (talk) 20:15, 25 December 2022 (UTC)[reply]
Thanks Zaereth. I send you my best wishes this festive season too!
Regarding the cold weather, I live in Australia and the forecast maximum temperature today is 29 deg C so keeping warm won’t be a problem! Regards, Dolphin(t)20:32, 25 December 2022 (UTC)[reply]
I'm a commercial pilot trying (for medical reasons) to calculate the pressure gradients between various low levels of altitude change to establish scientifically whether, and by how much, the pressure differences are greater at lower levels (nearer the ground) than the differences higher up for the same altitude change (please see my discussion title) as I understand the vertical gradient to be exponential rather than linear. Can you help me with the calcs please? Many thanks indeed, Dave UK Dmlewins (talk) 09:12, 10 March 2023 (UTC)d[reply]
Hi Dave. I’m willing to try to help.
The vertical pressure profile is definitely not linear. (It is worth noting that the vertical temperature profile IS linear. The temperature gradient is constant: 6.5 deg C per 1000 m or approx 1.98 deg C per 1000 ft.)
Yes, the vertical pressure profile varies exponentially. Some of the math is available at Barometric formula.
It is likely that your purposes can be served by reading pressures and altitudes from a table of the standard atmosphere. (I don’t have a paper table close at hand so I went to International Standard Atmosphere#External links and used the “Digital Dutch” online calculator given as the first of the external links.)
altitude sea level – pressure 1013.2 hPa
altitude 2,000 feet – pressure 942.1 hPa
difference 71.1 hPa or gradient of 35.6 hPa per 1,000 feet
altitude 4,000 feet – pressure 875.1 hPa
difference 67.0 hPa or gradient of 33.5 hPa per 1,000 feet
altitude 6,000 feet – pressure 812.0 hPa
difference 63.1 hPa or gradient of 31.5 hPa per 1,000 feet
altitude 8,000 feet – pressure 752.6 hPa
difference 59.4 hPa or gradient of 29.7 hPa per 1,000 feet
altitude 10,000 feet – pressure 696.8 hPa
difference 55.8 hPa or gradient of 27.9 hPa per 1,000 feet
Hi Dolphin 51, that's really helpful thanks very much!
You say though that the pressure gradient isn't linear (which I'm glad to hear), but then state what seems to be a linear relationship in the calc for the first low level altitude block of 35hpa or so per 1000'. How do I calculate the different gradients in the higher blocks? Fyi I'm trying to prove that the pressure difference per 1000' is much(?) less at 6000 and 8000'and less still at 10000'. Is this the case and if so by how much? Thanks again! 🙏 Dmlewins (talk) 10:57, 10 March 2023 (UTC)[reply]
The advancement to Distinguished Professor was a terrific honor, thank you for your kind comments. Remarkably, when I tried to respond to you a couple days ago, I found my IP was blocked due to a number of abuse notifications, though as you note I have not logged in for over a year. I have never appealed a block before, so it took me several attempts to get it right, and by then I was halted for spamming the request system. In any case, you have reminded me why it is nice to be back. Prof McCarthy (talk) 19:13, 22 May 2023 (UTC)[reply]
I agree that it is frustrating to be swept up in an IP-wide block. It happened to me a few years ago. Thank you for your acknowledgment, and welcome back. Dolphin(t)22:22, 22 May 2023 (UTC)[reply]
Still working at it
I'm getting there. It's a bit slow as I can't force it. I have to wait patiently for a light bulb to go on, then go looking for supporting material.Pieter1963 (talk) 00:13, 20 June 2023 (UTC)[reply]
No problem Pieter! It’s a big topic - I know, I attempted to save the article about 15 years ago. Thanks for letting me know. Dolphin(t)00:28, 20 June 2023 (UTC)[reply]
I'm still moving ahead slowly in fits and starts, no loss of enthusiasm though. I keep massaging what I've already done as well as coming up with new angles. I knew I'd find putting something together from scratch would be difficult although it's all very basic and, I think, interesting.Pieter1963 (talk) 01:07, 17 August 2023 (UTC)[reply]
An automated process has detected that when you recently edited Hydraulic head, you added a link pointing to the disambiguation page Bernoulli equation.
Hello, could you add the Czech Republic to the f-35 users in the f-35 article. The Czech government approved the purchase of 24 f-35s a few days ago. 193.165.236.247 (talk) 12:24, 3 October 2023 (UTC)[reply]
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I have a question about contrails that maybe you can answer. I asked Siri but she was no help...so I came to my old friend Wikipedia. The other day in the skies above central Illinois I witness a contrail that veered quite noticeably to the right. I didn't think much about it at the time and only watched for a minute or two and went about my business. But, later, I realized that in 60 years of watching the sky and cloud formations and thousands of contrails (I'm an artist) I had never seen any turn at all...always straight as an arrow. This drastic turn was peculiar. It was most likely just a change of course by the aircraft but it was so severe it defied my possible explanations. Thanks in advance for any explanation and Happy Holidays to you and yours.Buster7 (talk) 14:39, 17 December 2023 (UTC)[reply]
Hi Buster7. Sorry to butt in, but since I have this page on my watchlist I thought I'd give my two cents. In my experience, contrails can move due to things like air currents and jet streams, but somehow I get the feeling that's not what you're describing. Normally, when flying, the goal is to get from Point A to Point B in the shortest distance possible, that is, "as the crow flies". So when you see the high-altitude contrails of most commercial airliners they're typically going in very straight lines.
Perfect in theory, but as Yogi Berra once said, "In theory, there is no difference between theory and practice. In practice, there is." Other countries often don't like us flying over their airspace, and visa versa. Military bases don't like commercial planes flying over them, etc. So you end up with a lot of no-fly zones and corridors where travel is permissible. These become like highways, or airways, in the sky. For example, in the continental US, you'll most likely see contrails that are mostly moving in perfectly straight lines because these air lanes are long and wide. In Alaska, however, we have relatively narrow corridor here where planes are coming over the top from Europe and east from Asia. Anchorage serves as one of those landmarks to such planes that says, "Change course here." Thus, over Anchorage it's quite common to see a contrail turn where the plane did.
Now, a commercial plane is not likely to make any sudden turns. Passengers and cargo, not to mention the planes, don't like those. Even so, at cruising altitude of 30,000 feet (5 1/2 miles), to a person on the ground the turn will look a lot tighter than it is.
Military craft, of the other hand, can and do often make very tight turns, which from cruising altitude may appear as almost sharp angles. These are often not bound by the typical FAA regs and quite often fly above controlled airspace. With them, you neve know why they do what they do, but more than likely they have their turns all mapped out on a flightplan, or they're being guided somewhere by their controllers. (Or on rare occasion they may just be out having fun.) That's my best guess to try and describe what you saw. We can probably rule out UFOs, because those are notorious for not leaving any contrails. But perhaps Dolphin51 will know more about it than I. For a funny video about it, see: https://www.youtube.com/watch?v=ILop3Kn3JO8Zaereth (talk) 21:18, 18 December 2023 (UTC)[reply]
Hi Buster7. I generally agree with everything Zaereth has written. Two aspects of your description are significant:
This was the first time you have witnessed this occurrence so it is not a case of all aircraft on this course have to skirt around the corner of a control zone to avoid some no-go area, or to avoid leaving the protection of controlled airspace.
You could see the contrail so poor weather is unlikely to be a contributing factor.
One possibility is that this was a military aircraft, possibly on a training flight. A training flight could involve the crew planning to fly to Base A, but then being given a simulation of a mid-flight emergency that requires the crew to investigate all options and divert to the best alternate Base. Dolphin(t)01:38, 19 December 2023 (UTC)[reply]
You're welcome. One way to think about it is that flying is usually done from point to point. In the old days it was visually, from landmark to landmark, but today those landmarks have largely been replaced by navigational radio beacons. Either way, ideally you want to go directly from point A to B, but sometimes you end up needing to turn at Point C, D, and E in between. Emergencies happen and you suddenly have to divert to the nearest cornfield. Only the pilot really knows. (The old pilot's proverb says, "You've never been lost until you been lost at mach 2.") Zaereth (talk) 21:22, 19 December 2023 (UTC)[reply]
Merry Christmas!
Merry Christmas Dolphin51! Glad to see you're still around after all these years. I just wanted to stop by and wish you and yours a Merry Christmas! And, as always, if you don't celebrate Christmas, then take it as a Happy Hanukkah, a Blessed Hatsumode, or (my personal favorite) a hard-partying Viking Yule (which is what it is anyway), or whatever holiday you wish. If nothing else, have a great Sunday, and may the coming New Year be clear and a million with a good tailwind. Zaereth (talk) 21:46, 19 December 2023 (UTC)[reply]
Hi Zaereth! Thank you for your season’s greetings. I send my greetings to you and your family too.
I’m pleased to see the dolphins around San Luis Obispo are friendly. I have had a few great experiences travelling across open water in a boat, and was delighted to watch the number of dolphins racing beside the boat in the bow wave. How cool is this! Dolphin(t)20:27, 23 December 2023 (UTC)[reply]
Feedback request: Maths, science, and technology request for comment
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You have recently made edits related to genetically modified organisms, commercially produced agricultural chemicals and the companies that produce them, broadly construed. This is a standard message to inform you that genetically modified organisms, commercially produced agricultural chemicals and the companies that produce them, broadly construed is a designated contentious topic. This message does not imply that there are any issues with your editing. Additionally editors are not allowed to make more than 1 revert on the same page within 24 hours in this topic. For more information about the contentious topics system, please see Wikipedia:Contentious topics. KoA (talk) 02:21, 15 May 2024 (UTC)[reply]
I regret that you consider reverting your 'edit in order to insert the number “27.5”' to be 'grossly inappropriate'.
What you actually did was insert the number 2.75 to replace the number 27.5 when both are obviously wrong.
Reverting your wrong number could be justified by the fact that you did not provide a Reliable Source to support it and practically admitted on the talk page that you came up with it out of thin air. Personally, I do not care enough to fight about it.
If I could find a reliable source for making a valid correction, I would have made it myself to begin with.
It should be obvious that under these circumstances I do not fault you for not finding a source either.
When I reverted your edit, I had no idea that you are a fellow engineer with some personal knowledge about the topic.
I want to clarify that I had no intention that reverting your edit would reflect badly on you.
If it does, please let me know what I can do to correct that.
My reason for reverting your edit was that I am not clear where the original wrong values for both Iron and Nickel came from and I prefer not to obfuscate the history. If somebody else wants to research and find the source so they can improve the article, it would be easier for them to have the unaltered original (wrong) values. It is possible (though unlikely) that whoever entered these numbers that seem wrong to both of us knew something that we do not.
As to vandalism, I have seen much worse behavior on Wikipedia.
In my experience, those who accuse me of vandalism usually reflect more about themselves than they do about me.
I have learned that arguing with Wikipedians with an agenda just to expose their bias is futile.
I have seen enough to understand why there are so few active Wikipedians willing to self identify as anything other than male.
If you feel strongly about it, please feel free to wait a day and then undo my reversion yourself.
If you do, I promise to walk away and stop contributing to Wikipedia for a few months (as I have done before several times).
In the unlikely event that someone accuses you of an edit war for doing so, this post should be enough to prove them wrong.
Since we actually seem to agree about the facts in this case, I see no point in arguing with you.
We seem to have more in common than in dispute. I hope that next time we meet here, we'll have a better opportunity to collaborate.
Good luck and thank you for trying.
Annette Maon (talk) 03:31, 7 August 2024 (UTC)[reply]
Hi Annette Maon. Thank you for writing this comprehensive explanation on my Talk page.
The offending table of yield values contains numbers less than 10, with the exception of the number 27.5. This number is conspicuously anomalous. The most likely explanation is that the decimal point is simply in the wrong place. I edited the table to move the decimal point one place to the left so all numbers in the table are consistently in the expected range between 0 and 10. That is very different to coming up with a number “out of thin air”.
The table in question was inserted from an IP address on May 18, 2018. Unfortunately this IP address has been inactive on Wikipedia for about 5 years so we can’t expect to be able to alert them to the problem and they might repair the anomaly and provide a citation of their source. This situation is very common on Wikipedia.
You have suggested that seeing the table is unsourced, and my edit was also unsourced, that any User is free to amend the table, or my edit, by inserting other unsourced information even if can be seen to be incorrect. (The number 27.5 is clearly inconsistent with all other numbers in the Table.) That is incorrect - Users are never at liberty to knowingly insert inaccurate or incorrect information, even if only replacing unsourced information.
When planning to revert another User’s edit please decide very carefully. Many Users take offence when they make a constructive edit but that edit is subsequently reverted in a way that is not constructive or not done in good faith. Dolphin(t)22:52, 10 August 2024 (UTC)[reply]
I note that you have chosen to undo my reversion yourself.
Here are some observations I would like to bring to your attention before I walk away and stop contributing to Wikipedia for a few months.
There are several more likely explanations for the 27.5 number than "that the decimal point is simply in the wrong place".
2.6 GPa is very close to the upper range quoted for the yield stress of Maraging steel (google search for "strongest steel tensile strength").
The strongest steels (Maraging, AerMet) have martensite rather than ferrite (α-Fe) crystal structure.
α-Fe is the crystal structure of both pure iron and (unquenched) low carbon steels
The yield strength of pure iron (see Fig 11 in the article below) can be as low as 0.2GPa (More than 10x less than Maraging steel).
The differences in yield and ultimate strengths between pure iron and low carbon steels can be huge.
Both Iron and steel are ductile so strain hardening can easily reach an ultimate strain 10x larger than the yield strain.
Strain hardening significantly increases yield stress as well but is not likely to give a factor of 10 by itself.
Figure 7 (Cumulative probability of calculated shear stress for a first pop-in) shows experimental results up to 1GPa demonstrating significant ductility beyond 0.8GPa. While ultimate strength may be higher than 1.0GPa, it is obvious that the yield strength of untreated pure iron is much lower.
Figure 10 shows that plastically prestrained and aged samples may have a higher yield strength.
Figure 11. "Stress–strain curve (tensile test) of the pure iron" shows the ductile range of pure iron.
Unfortunately, this article does not appear on the WP:RSP list so any idiot can dispute its relevance, especially if they can get several other editors or a few admins to vote their way. Besides, everything I wrote here is my personal WP:OR. As a WP:GNOME I would not presume to use it in my own edits.
I hope that you or someone else will be able to use these observations to improve the quality of Wikipedia.
I will come back in a few months and see if that actually happens.
You seem to have some very personal and eccentric views on what "encyclopaedic language" is and is not; please don't impose these on the project! There is absolutely nothing wrong with "as such" and "in all" in the right context. We are supposed to write in as clear and simple a style as possible. I suppose your background is to blame for your tendency to load the text up with long Latinate words, the absolute reverse of what we are supposed to aim for. This is generally recognised as a problem with many medical editors who are doctors (or, even worse, medical students), who are trained to write this way. I've looked at a small number of your language-related edits, and most needed reverting, which is a waste of everybody's time. Johnbod (talk) 13:23, 14 August 2024 (UTC)[reply]
Johnbod Thank you leaving me a message. It is rare for a User to offer to discuss after deleting an edit.
I will cease imposing my personal and eccentric views at Wikipedia if you will do the same. This is how it will work:
When you’re ready to cease imposing your personal and eccentric views, notify me on this Talk page. It will be sufficient to leave a message saying “Beginning today, I will not impose a personal or eccentric view on my edits to Wikipedia.”
I will then monitor approximately 100 of your edits. If I’m satisfied that you’re true to your word, and you have ceased imposing views that might be considered personal or eccentric, I will do the same.
Well, I notice you are not denying it! I'm not aware that I do in fact have any "personal and eccentric views on what "encyclopaedic language" is and is not" - you are welcome to monitor as many of my edits as you like & let me know if you think you've found any. I'm also concerned you may not easily recognise what actually is "personal and eccentric" in your language edits, which rather negates the value of your proposed undertaking. I have a degree in English (many moons ago) & you will see from the top of my userpage I have had experience working with many very large organizations, with some of the work involved in working on appropriate language for Wikipedia's readership. Plus I've a lot of FAC work. So I'm fairly confident I'm mainstream on this. Thanks for responding anyway. Johnbod (talk) 14:21, 15 August 2024 (UTC)[reply]
Johnbod Thank you for inviting me to let you know what I find when perusing your edits. In the spirit of helping a fellow User navigate the mysterious ways of Wikipedia, I’m very happy to do so.
Wikipedia has many policies, guidelines and essays that can help Users work constructively and harmoniously with others. These policies, guidelines and essays can be accessed using blue links. They have been written by multiple experienced Users, and they are constantly available for perusal and amendment. They represent a mature view of how the project should proceed. When a claim is made about how Users should perform, it is important that a blue link is supplied to support the claim. If no blue link is supplied, other Users may assume that the claim is a personal view and lacks the maturity that comes from involvement by multiple Users. In your 2 posts on my Talk page you made no attempt to supply any blue link so I have little alternative to assuming your claims and your views are personal. For example, you have written “We are supposed to write in as clear and simple a style as possible.“ I’m not aware of any Wikipedia document that says precisely this, and you have supplied no blue link to support you, so I will assume you are happy to present these words as nothing more than your personal view. Perhaps you should have made a blue link to WP:TONE in which case we can have a discussion about whose views are more compatible with this guidance document.
You have implied that many of my edits display a lack of knowledge of what constitutes encyclopaedic language. Naturally I’m interested to learn what sort of editing you have in mind. Naturally I’m interested to see an example or two of the edits you are alluding to. But what you provided was this: I suppose your background is to blame for your tendency to load the text up with long Latinate words, the absolute reverse of what we are supposed to aim for. This is generally recognised as a problem with many medical editors who are doctors (or, even worse, medical students), who are trained to write this way. Here I see a conspicuous mismatch between your opening with some obscure insinuations, and your ending with amateurish analysis of me personally and medical doctors and medicine students. At the very least, it is eccentric coming from a university graduate.
In your messages to me you wrote You seem to have some very personal and eccentric views on what "encyclopaedic language" is and is not; please don't impose these on the project!. You also wrote I'm also concerned you may not easily recognise what actually is "personal and eccentric" in your language edits ... These comments are inappropriate because this is not the way Wikipedia operates. Wikipedia does not require minimum qualifications or skills from its Users. No User is ever disqualified or discouraged on the grounds of having inadequate skills or eccentric views. Wikipedia is the encyclopaedia that anyone can edit so there is no legitimate strategy for improving the encyclopaedia by disqualifying persons who are considered to have inadequate qualifications, knowledge or skills. Wikipedia does not attempt to intimidate Users by telling them about their shortcomings. For example, if a User has poor spelling skills and leaves many spelling errors, Wikipedia doesn’t humiliate, intimidate or discourage - instead we simply edit our articles to correct the spelling errors. If you are attempting to discourage me with allusions to undisclosed errors in my editing work, you will find no support from Wikipedia. It remains the encyclopaedia that anyone can edit.
I applied the important principle of WP:BOLD and made edits to the 2 articles at the heart of our discussion. You reverted them inappropriately. Wikipedia has some very sound and valuable ideas that say:
Wikipedia does not have a bias toward the status quo ...
In fact, Wikipedia has a bias toward change, as a means of maximizing quality by maximizing participation.
I suspect that in reverting my good-faith edits in order to restore your personal preferences, your actions were in defiance of the very sound principles at WP:ONLYREVERT. If you want to persuade me that your reversions were reasonable you must do so using the criteria at WP:DOREVERT. Happy editing. Dolphin(t)07:35, 18 August 2024 (UTC)[reply]
We have plenty of guidance on editing style, though most of it is in training materials and essays rather than encoded in policy, where it is hard to define and subject to complaints of WP:CREEP. There's no need to explain WP policies to me; I helped write a good few of them. Your edits were not especially WP:BOLD, they were just bad. Meanwhile, here's some reading for you. Johnbod (talk) 14:47, 19 August 2024 (UTC)[reply]
Your original criticism of my work included mention of my tendency to load the text up with long Latinate words. You still have provided no clarification of what you mean, and no example to support your criticism. I don’t know any Latinate words so I’m curious to know how I might be loading the text with words I don’t know.
You also complained that I've looked at a small number of your language-related edits, and most needed reverting. You have provided no clarification of what you mean, and no example to support your criticism. Please do so. Dolphin(t)12:44, 21 August 2024 (UTC)[reply]
Don't undersell yourself - you know plenty of Latinate words and used several in your first sentence above; I'll bold them for your convenience: "Your original criticism of my work included mention of my tendency to load the text up with long Latinate words. You still have provided no clarification of what you mean, and no example to support your criticism." Of course many Latinate words can't be avoided in normal English, but there are many places where a simpler word derived from Anglo-Saxon is preferable. The first edit of yours I reverted replaced "as such" with "consequentially", not only a slight change of meaning away from precision, but the introduction of a long Latinate word to replace two simpler and shorter (and as it happens more precise) A-S words. Hope that helps. Johnbod (talk) 19:05, 21 August 2024 (UTC)[reply]
Johnbod Thank you for analysing two of my sentences and bolding the Latinate words. In 2 sentences I used no fewer than 8 Latinate words! Goodness me, I do have a tendency to load the text up with long Latinate words.
However, I’m not aware of Wikipedia having a policy of opposition to Latinate words where Anglo-Saxon words will do just as well. When I asked you about the origin of this viewpoint you replied (19 August) We have plenty of guidance on editing style, though most of it is in training material and essays rather than encoded in policy, where it is hard to define and subject to complaints of WP:CREEP. I assume this training material and these essays are not Wikipedia documents. Perhaps they are documents you have on your bookshelf at home.
You are very knowledgeable about Wikipedia’s policies. Can you identify a policy that requires Wikipedia Users to write their edits in accordance with the training material and essays you mentioned in your 19 August post? Dolphin(t)13:27, 22 August 2024 (UTC)[reply]
(ec) Probably not - As I explained above we don't like to define style stuff inpolicy very tightly. User:Tony3 might know. But you are wrong to "assume this training material and these essays are not Wikipedia documents." Here is one example: Wikipedia:Use plain English. Johnbod (talk) 14:08, 23 August 2024 (UTC)[reply]
Much of this discussion is focused on editor conduct, which is outside the remit of WP:3O. The dispute relates to the replacement of the words "as such" by "consequently". Two examples are provided diff1 and diff2. In my personal opinion, as a native English speaker with no formal language training beyond secondary school, is that both options are acceptable, although my preference would be for "as such". This is because when writing an article we should strive to keep the content as clear and understandable as possible. readability is important. Polyamorph (talk) 20:28, 23 August 2024 (UTC)[reply]
Polyamorph Sadly, this is a most superficial response to the disagreement that is clearly visible in this discussion thread. The disagreement has never been about whether people prefer “as such” or “consequently”.
The disagreement began when Johnbod began this discussion thread, writing You seem to have some very personal and eccentric views on what "encyclopaedic language" is and is not; please don't impose these on the project! This is adversarial and provocative language, so I was immediately curious as to what grounds John had for confronting me with these accusations.
Possibly as his attempt to justify his accusations, John then wrote I suppose your background is to blame for your tendency to load the text up with long Latinate words, the absolute reverse of what we are supposed to aim for. This is generally recognised as a problem with many medical editors who are doctors (or, even worse, medical students), who are trained to write this way. Here we see the accusation that I have a “tendency to load the text up with long Latinate words.” Again, John makes no attempt to justify these accusations directed at me, but he does get distracted into providing an amateurish analysis of me personally, and medical doctors and medicine students! I am an engineer; I am not a medical person!
In several of my posts I pressed John to identify a Wikipedia document that informs Users that they should avoid Latinate words where possible. Finally he identified the document WP:Use plain English. This document does not contain the word “Latinate” or anything that can be construed to be equivalent to the word Latinate!
I asked John if there is a policy that might support his accusations against me regarding long Latinate words. He replied “Probably not.” He suggested another User, Tony1, might know whether such a policy exists. It was Johnbod who came to my Talk page and made accusations against me and my editing, not Tony. It is Johnbod who must give an account of his actions here, not Tony or anyone else.
The above comments show the nature of the disagreement to be seen here in this discussion thread. The disagreement has nothing to do with the preference between “as such” and “consequently”. Dolphin(t)06:40, 24 August 2024 (UTC)[reply]
If I had not provided the diffs what would you have done?
The expectation was that someone would provide a third opinion on the disagreement visible in the discussion thread. Third opinions are not confined to examining diffs. Dolphin(t)07:01, 24 August 2024 (UTC)[reply]
I would have likely declined it if there was no obvious content dispute. Johnbod mentioned changing “as such” and "in all" and you provided the diffs. So the idea that The disagreement has never been about whether people prefer “as such” or “consequently” is nonsense. That is precisely what the content dispute is about. I have provided my opinion on that, any discussion about accusations of provocative / adversarial language or who should be accountable for their actions, is irrelevant to me. Polyamorph (talk) 07:18, 24 August 2024 (UTC)[reply]
The disagreement is mostly about Latinate words, and whether Wikipedia discourages their use. I believe Wikipedia says nothing to proscribe or discourage their use. Johnbod suggests their use is proscribed or discouraged although he hasn’t provided anything to support his suggestion. Dolphin(t)14:26, 24 August 2024 (UTC)[reply]
There is no policy or guideline discouraging the use of Latinate words. That said, there is also no policy or guideline encouraging them, and certainly no guidance that indicates they are "more encyclopaedic". As such, their use is a matter of writing style. In my WP:3O response I indicated both examples are acceptable writing styles. However, the wikipedia manual of style states "Editors should write articles using straightforward, succinct, easily understood language". I would suggest that "as such" is more clearly understood than "consequently". Although I would not change one for the other, per the WP:MOS
When either of two styles is acceptable it is generally considered inappropriate for a Wikipedia editor to change from one style to another unless there is some substantial reason for the change.[c] Edit-warring over style, or enforcing optional style in a bot-like fashion without prior consensus, is never acceptable.[b][d]
Exactly! I made it perfectly clear above that I had no objection to using Latinate words as such; indeed it is almost impossible to avoid doing so in English. Nor is there any general objection in Wikipedia guidelines. What really struck me, and annoyed me, about the edits I reverted was the edit summary "replaced unencyclopaedic words with one more appropriate to an encyclopaedia". That "as such" is "unencyclopaedic" is just wrong. Dolphin's edit was a move in the wrong direction, for the reasons you give, but without the edit summary I probably wouldn't have reverted it, or come here to explain why. I certainly don't go around wp hunting down "consequently" or other long words. Johnbod (talk) 16:49, 24 August 2024 (UTC)[reply]
Johnbod. Thank you for that clarification. At WP:DONTREVERT it says Do not revert an edit as a means of showing your disapproval of the edit summary.
Following these most recent edits by Polyamorph, you and me, I think we have reached a suitable end point. We see at least one idea the other was trying to present. I doubt there is anything to be achieved by starting in another direction.
Hi, Dolphin. I hope I am writing in the right section. I am a complete novice (ignorant would be a more appropriate term) at this. Thanks for your patience, and for responding, and for making the case of the dimensionless coefficient CD0 being unable to compare the ability of generating lift by different aircraft. This already tells me you may (in principle) agree about the limited use of dimensionless coefficients in aerodynamics. Another example: the CLmax of a cylinder in Magnus effect is around 9, six times higher than the CLmax of an airfoil, at around 1.5. Following your argument, Dolphin, we should not compare these two values of CLmax either (which I agree with you). As a conclusion, you and I would, in principle, agree that the CD0 and CL are numbers that are useless in comparing different aircraft (which is, actually, very unfortunate!). When I say there is "something basically wrong in aerodynamics", may I extend my case to the absence in the use of "pressure" (as we know it, namely, a force acting over an area, as used in thermodynamics) and the absence of aerodynamic work? Of all sciences, should "pressure" (and I am not talking about the "dynamic pressure", a "pressure construct", in my opinion) be all over the place in our calculations as aerodynamicists. We should probably be owning the concept of "pressure", not thermodynamicists...but... we barely use this concept...only when calculating the wing loading of a lifting surface or a flying wing, or calculating the parasite drag over the frontal area. I have bored you enough already. If you are lucky, my ranting may have gotten lost in the ether.... Phil. Philburgers (talk) 23:19, 1 September 2024 (UTC)[reply]
Thanks Phil. You have written to me at precisely the right place!
First, a little clarification. You wrote compare the ability of generating lift by different aircraft. This is the first time lift has been mentioned. Are we talking about drag coefficients, or dimensionless coefficients in general? Dolphin(t)23:53, 1 September 2024 (UTC)[reply]
Hi, Dolphin! The variety of topics of your interest is breathtaking (unless I am misreading the left column on my screen). Yes, indeed, I am talking about the inability of CL and CD0 of different aircraft to be compared, which brings up the question: If you know the CD0 of a F-104 is 0.0172 (using wing planform area as the reference area), what do you do with it? Not much, indeed.
Ohh, dear.... Dolphin, I will safe you reading time here. If you agree with the fact that CDi=CL^2/Pi.AR.e, then I cannot help you much. An experimental link has no yet been found between CDi and aspect ratio AR. I have recreated the derivation of our beloved CDi coefficient, and found it being a product of two dimensionless numbers, one being CL. I see I can email you stuff... I will try that. Tata. Philburgers (talk) 14:49, 2 September 2024 (UTC)[reply]
One more thing ,Dolphin: In one of the figures in your interesting note on induced drag you mention the "uniform downwash" that is generated, according to your drawing, by a wing of rectangular planform. You may want to check if the planform for generating said uniform downwash is generated by wings of elliptical planform. Philburgers (talk) 15:05, 2 September 2024 (UTC)[reply]
Thanks for the tip about the diagram showing a rectangular planform. I have amended the caption to remove the suggestion that the downwash is uniform.
Even though I am using the diagram, and I can create my own caption, the image was created by another User. Sadly, I don’t have the skill to create diagrams and upload them to Wikipedia.
In general, if you tap once on a photograph or diagram on Wikipedia, you will get a full-screen version of the image, and in the bottom left-hand corner you will see the name of the User who contributed the photograph/diagram. Often, it is possible to write to that User at their Talk page and make comments or request changes to the diagram. Dolphin(t)01:56, 3 September 2024 (UTC)[reply]
Newton and lift
Hi Dophin,
I don't want to clutter the talk pages with discussion of the subject (as opposed to how to improve the article) so I'm moving it here. We seem to have a basic disagreement re Newton's 3rd law and it's usefulness (or lack thereof) in explaining aerodynamic lift. Maybe it's just a misunderstanding, so I thought I'd clarify my perspective. For one thing, I'm a sailor, not a pilot or aircraft designer, so my interest in lift is to propel the boat rather than to keep it in the air. In my day-to-day experience, buoyancy is sufficient to keep the boat from sinking; I don't need lift for that. (c:
In the comments at the Magnus effect page you presented some quotes from McLean and Lanchester to the effect that there is no net deflection of the air in the atmosphere. I agree that this is true for an aircraft in straight and level flight at a constant speed, and we don't need to take McLean's or Lanchester's word on it: if the aircraft is flying straight and level with constant speed, it's momentum is constant. Applying the law of conservation of momentum leads to the immediate result that there is no net momentum change of the air.
This is true for both fixed wing aircraft and helicopters. The apparent paradox is that anybody who stands underneath a hovering helicopter will experience an undeniable downward rush of air. There is also unmistakable downwash behind a fixed wing aircraft. So what gives?
A thorough analysis has to include the ground - eventually the pressure wave from the aircraft reaches the ground, where it meets an upward force, causing the air to accelerate upwards and cancelling the downward momentum imparted by the wings or copter rotor. I'm eliding over a lot of details here, but the main thing is that if the aircraft has constant momentum, then the momentum change of the air must be zero.
Now, let's turn to a different example: a sailboat that it initially at rest (momentum == 0). The sailors trim the sails and the boat accelerates to some speed, v. It now has a momentum of mv in whatever direction it is going. Again, applying the law of conservation of momentum, the air must be accelerated in the opposite direction and have a total momentum change of -mv. This is not something that is illusory or temporary or an artifact of the model. It is very real.
Similarly, a ball that is spinning with a vertical axis experiences a horizontal change in momentum with an associated horizontal change in momentum of the air. In some ways, by ignoring gravity (which we can do for horizontal lift forces, at least in the first-order analysis) lift becomes easier to understand - we don't have the paradox of local deflection but no net deflection.
More generally, whenever there is aerodynamic lift, two things must occur:
There must be pressure differences. The only way a fluid can exert a force on an object are 1) pressure , 2) shear stress, and 3) gravity. Shear stress is always parallel to the air velocity, so it can't contribute meaningfully to the lift since it's in the wrong direction, gravity is too weak to be relevant, so that leaves pressure as the "hands that transmit the force" as John D. Anderson likes to say.
The fluid is deflected in the direction opposite to the lift force. If the fluid exerts a force on a solid object, the object must exert and equal but opposite force on the fluid. Since a fluid has no solidity, it must accelerate in response to that force.
During the great 1990s debate over Newton vs Bernoulli, some Newtonian advocates would erroneously claim that there were no pressure differences, incorrectly citing the Equal Transit Time Fallacy as "proof". Conversely, some Bernoulli advocates would deny the deflection, citing either the no-net-momentum-change analysis above, or 2D potential flow which fails to predict either deflection or stall. I would hope that in the ensuing two-dozen years we've gotten beyond that.
Here in the US, NASA likes to explain lift as a result of flow turning. Deflection is a result of flow turning, so there's some merit to the argument that deflection is an effect of lift, not it's cause, but my take that this is a sufficiently subtle distinction that deflection-based explanations are fine for simplified discussions - flow turning and deflection are basically the same thing unless you want to split hairs. And the logical connect between flow turning and the resulting force on the solid object is that they form a reaction force pair, which follows from Newton's 3rd.
To sum up, flow turning, deflection, and Newton's 3rd are one way (but not the only way!) to explain lift. I think we resolved this over at the talk page of Lift(force) some time ago. And since the Magnus effect is just an example of aerodynamic lift, the well sourced NASA-favored explanation has a place in that article.
Hi Mr swordfish. Thank you for visiting my Talk page to continue the discussion. I appreciate it.
I accept that I'm giving the impression that I'm opposed to the notion that Newton's 3rd law has a place in explaining lift. I'm not opposed to it, and I apologise for giving that impression. I have no patience for oversimplified explanations such as "Lift is caused by Newton's 3rd law". I acknowledge that you have never written anything as unsound as this but we have both seen these ideas and it partly explains why I'm on guard when Newton's 3rd is mentioned. Similarly we have both seen "Bernoulli has nothing to do with lift on an airfoil" coming from advocates of Newton.
A very sound explanation of lift exists in the form "First there is A, which leads to B, and finally there is C" where C is Newton's 3rd law. Unfortunately the advocates of Newton sometimes completely omit A and B, and go straight to C which is Newton's 3rd. If C (Newton's 3rd) on its own is a satisfactory explanation of the lift force on a wing it should also be a satisfactory explanation of all other forces. For example, if the question is "Why does the needle of a magnetic compass point to magnetic north?" would we accept "Newton's 3rd law" as a satisfactory answer? Obviously not. Any satisfactory answer invoking Newton's 3rd law should start with A and B before launching into C.
Another regularly seen element of the Newtonian explanation of lift is "the wing deflects the air downwards". There is a little truth in this, but it isn't where most people are looking. In the case of an airfoil or wing flying horizontally people write "the air approaches the wing horizontally and is deflected downwards". That statement is so misleading I would prefer to call it false; it is not describing the deflection that is associated with aerodynamic lift.
Streamlines and streamtubes around an airfoil generating lift. The flow is two-dimensional and the airfoil has infinite span. Look at this wonderful diagram prepared by Michael Belisle. I suspect that many people look at the orientation of the airfoil and at the slight downwards direction of the entire flow aft of the trailing edge, and say "there it is, that shows the air deflected downwards". They overlook the fact that the entire flow approaching the leading edge is heading slightly upwards. The downwards component of momentum of the flow just aft of the trailing edge is equal to, but in the opposite direction to, the upwards component of momentum of the flow just ahead of the leading edge. When the flow arrives at the airfoil it is not moving horizontally; it has been deflected upwards. Its upwards velocity does not explain a downwards force (negative lift?) on the airfoil; and its downwards velocity just aft of the trailing edge does not explain an upwards force (lift).
Aerodynamic lift is associated with the clockwise rotation of the velocity vectors. It can be seen roughly between the leading edge and the trailing edge. We can call it a region of "downwards deflection" although a better description might be "downwards acceleration". This is where the real action takes place; where the streamlines are conspicuously closer together and where the pressure is at its lowest. But I doubt many people are looking there when they write "the wing deflects the air downwards". People can look at a wing or airfoil orientated at around 5 degrees trailing edge down, and think it is causing the air to be deflected downwards by 5 degrees. I doubt many realise that what is causing the lift force is that the airflow approaches the leading edge at 5 degrees above the horizontal, and departs from the trailing edge at 5 degrees below the horizontal. The air hasn't really been deflected downwards but its velocity has been rotated clockwise (in Belisle's diagram.) There is also some clockwise rotation in the flow below the airfoil.
Lift generated in two-dimensional flow (around a uniform wing of infinite span) is accompanied by zero drag. This is obvious if we focus on the fact that air flowing at 5 degrees above the horizontal is rotated to become air flowing at 5 degrees below the horizontal. However, if we focus on air flowing horizontally to become air flowing downwards at 5 degrees we must acknowledge that the force on the lifting body (and the air) is not vertical - it has a small horizontal component called lift-induced drag. We know there is no lift-induced drag in 2-D flow, so the idea that the air arrives at the wing flowing horizontally and then generates lift must be incorrect.
In Doug McLean's book he presents a brilliant diagram at Figure 7.3.23. It shows that in two quadrants around an airfoil the flow is "downward turning", and in the other two quadrants the flow is "upward turning". I have not seen this diagram before so I'm very grateful to Doug for it.
In the early days of aviation the Wright brothers, who were bicycle builders, made themselves a wind tunnel and learnt much testing carefully made models. They could measure forces and moments but weren't able to determine much about where the air was going or how lift was generated. Elsewhere, mathematicians Lanchester, Joukowsky, Kutta and others were trying to comprehend lift and drag using mathematical methods. I imagine that, initially, they tried to explain lift using linear concepts such as air flowing in a straight line and then being deflected downwards in order to continue flowing in another straight line. Even though these three were working independently, they convinced themselves that these linear concepts weren't satisfactory. Each one came to the conclusion that aerodynamic lift was related to air rotating around a fixed point - a vortex. It mattered little if a uniform flow was superimposed on the vortex because the linear features of the resulting flow did not participate in the generation of lift. Attempts at explaining lift using linear concepts such as the air "approaching horizontally and being deflected downwards" will meet with only limited success, as was discovered by the pioneering aeronautical mathematicians. So I shouldn't be surprised when linear concepts prove unsatisfying.
In the case of the Magnus force, I would prefer to see something like "Air arrives at the cylinder with a velocity with a small upwards component. It then experiences a downwards acceleration causing it to leave the vicinity of the cylinder with a small downwards component. The downwards acceleration is caused by the cylinder exerting a downwards force on the air. The cylinder experiences an upwards force and Newton's 3rd law of motion predicts that the two forces are equal in magnitude but opposite in direction."
Agree that saying "Lift is caused by Newton's 3rd law" is insufficient. As you say above, it needs some context, such as
Lift occurs when a moving flow of gas is turned by a solid object. The flow is turned in one direction, and the lift is generated in the opposite direction, according to Newton’s Third Law of action and reaction. Because air is a gas and the molecules are free to move about, any solid surface can deflect a flow.
This comes from NASA's Glenn Research Center at [3].
Of course, there are many other ways to analyze this complex subject, but that doesn't make this simple assertion wrong.
I would encourage you to think carefully about situations where the lift force is perpendicular to gravity, such as a sailboat or a slicing golf ball. When lift is not opposing gravity, it becomes obvious that the air is deflected in accordance with the law of conservation of momentum.
Also one tacit set of assumptions that may influence our thinking is that for airplanes, the objective is to generate just enough lift to keep the plane in the air, which leads to a small angles of attack far away from the stall and consequently only a relatively small amount of deflection. Conversely, sailboat sails are set to maximize lift, which occurs just before the stall point. The larger angle of attack, right on the edge of stalling, makes for a relatively large amount of deflected air. And as I explained above, since the deflection is horizontal, not vertical, there is a substantial net deflection of the air for a horizontal lift force.
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