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Computing Information

June 22 Information

Is there a rootless app or USB cable to use one of your Android smartphones as an in-out device/terminal for another of your Android smartphones when they're next to each other? Only one is new USB. Sagittarian Milky Way ( talk) 18:49, 22 June 2024 (UTC) reply

Can you explain what you mean by "in-out device/terminal"? Do you mean that you want to copy data from one phone to the other? CodeTalker ( talk) 07:20, 23 June 2024 (UTC) reply

Remote desktop except phones instead of PCs. Should I trust such apps? (if from the Play store) Sagittarian Milky Way ( talk) 21:23, 23 June 2024 (UTC) reply

Does Chrome Remote Desktop work for you? Dja1979 ( talk) 14:29, 2 July 2024 (UTC) reply

June 25 Information

Now that the MTVNews.com archives are gone, and there are quite a few links to it, do we ask the InternetArchiveBot people to run their bot on all pages that contain that url? How does that work? Polygnotus ( talk) 06:20, 25 June 2024 (UTC) reply

Either someone already did so or no one ever cited it to begin with. 2603:8001:4542:28FB:8DF1:8D96:7CF0:D084 ( talk) 14:11, 25 June 2024 (UTC) (Send talk messages here) reply

I believe so. Otherwise, you need to try to salvage broken links yourself. Outside of Internet Archive there is also archive(dot)is/archive(dot)today as well, which could be worth a try. Hanoi2020 ( talk) 17:05, 30 June 2024 (UTC) reply

June 28 Information

On Google maps the displayed map can be dragged in any direction by the mouse held with left button down. To do this in a script I hope to use this HotKeys command:

MouseClickDrag Clicks and holds the specified mouse button, moves the mouse to the destination coordinates, then releases the button.

MouseClickDrag, WhichButton, X1, Y1, X2, Y2 [, Speed, R]

On testing the mouse does move to the expected positions (x1,Y1) and (x2,Y2) but the map fails to move. Can someone say what I need to do to drag the map without mouse?

Comment: Attempting to slow the auto mouse by inserting 100 for Speed did not help. I also tried this sleepwalking version with 1-second waits between operations:

Sleep, 1000      ;sleep 1 second
MouseMove, 451, 314 ;map top left
Sleep, 1000
Send, {LButton Down}
Sleep, 1000
MouseMove, 691, 474 ;This where I want the map to be dropped
Sleep, 1000
Send, {LButton Up}

As before, the mouse moves as expected but the map fails to drag. Note: this is on Windows 10. MouseClickDrag works ok for drawing lines in PAINT.exe. Philvoids ( talk) 18:44, 28 June 2024 (UTC) reply

My first assumption is that you need two left button presses. Google Maps already has key bindings to the cursor keys to move it up, down, right, left. But, when you initially open Maps, it has focus on the search box. You have to click on the map once to put focus on the map. Then, the cursor keys and + and - work. So, your key bindings may not work without first clicking on the map, which I assume you can script, and then click-dragging. But, in my mind, this would be a cute project to work out how many cursor key presses it takes to move to a specific point and interleaving them so it appears to move diagonal instead of left to a point and then down to the final point. 12.116.29.106 ( talk) 11:34, 2 July 2024 (UTC) reply

I invoke Google maps from a Wikipedia geographic location so it displays with the Search box already filled. Just a single left-mouse-press is enough to start a drag. Thank you for the tip about the up/down/left/right arrow keys - they drag in large steps while the left mouse key is held down. Yes, you have the seed of a cute useful project for extracting wide-area high resolution maps from Google. Unfortunately the arrow keys do not work on this scan of an old map so this will not help the "Download image from website" question above. Philvoids ( talk) 12:19, 2 July 2024 (UTC) reply

July 4 Information

Is there a way to choose a specific country (where the connection appears to come from) when one uses the free VPN feature of the Opera browser? I installed Opera and when I tried to choose the country it only gave me the option between several regions of the world (Europe, Asia, North America, ...) but not how to pick a specific country in those regions. The explanation of their Help Chatbot was either unintelligible or false. Has anyone here used Opera and their free VPN and can they tell me if what I want to do is possible? Or is that a feature of their pro VPN? How about other free VPNs (like ProtonVPN): do they allow the free choice of the country or is that a premium feature that only paying VPNs allow? 178.51.74.75 ( talk) 06:51, 4 July 2024 (UTC) reply

According to the comparison chart at [1], the free Opera VPN has "3 general locations" and the paid version has "30+ unique locations" but doesn't say if you get to choose a country or if there are just more region choices. There is an Opera forum at [2] where you might be able to get more information. RudolfRed ( talk) 18:46, 4 July 2024 (UTC) reply

Science Information

June 20 Information

Could there have been agriculture hundreds of thousands of years ago before the last ice age? Rich ( talk) 08:12, 20 June 2024 (UTC) reply

Some group of dinosaurs could have had agriculture millions of years ago before they were all wiped out for all we know. But see the big box at he top of this page, one of the things it says is "We don't answer requests for opinions, predictions or debate" NadVolum ( talk) 08:19, 20 June 2024 (UTC) reply

Very unlikely. I suggest you read Mannion, A. M. (5 December 1995). Agriculture and Environmental Change: Temporal and Spatial Dimensions. Wiley. ISBN  0471954780. or similar. Agriculture depends on the domestication of crops and animals and its main centres were in areas of the world that were not covered in ice. Hence we would see archaeological traces whenever that had occurred. Mike Turnbull ( talk) 09:29, 20 June 2024 (UTC) reply

Ant–fungus mutualism is often considered a form of agriculture, and it developed millions of year ago. -- Amble ( talk) 17:23, 20 June 2024 (UTC) reply

Humans were slow starters. ← Baseball Bugs ^{What's up, Doc?} carrots→ 01:28, 21 June 2024 (UTC) reply

Scientists can never be sure about their theories. A good theory explains the patterns they observe. But errors can creep in, both in the process of obtaining observations and in recording them. Also, in a laboratory experiment one can perhaps make direct uninterpreted measurements, but in the field observations require interpreting the raw data, and the interpretations themselves depend on theories whose validity can also be subject to doubt. A pattern may be manifest while not being due to some underlying process but emerging by pure chance. And, finally, there is always the possibility of new observations uprooting a generally accepted theory. As to human agriculture, the currently best available explanation of the observations is that sedentary agriculture was an innovation that emerged in a few places and spread out from these during the Neolithic.  -- Lambiam 19:46, 20 June 2024 (UTC) reply

There may have been some earlier domestication attempts in the warmer periods on either side of the Last Glacial Maximum. I recall hearing that Zohary wondered if wheat didn't go back 20,000+ years, and lately there's been some talk about olives and pine nuts, which of course wouldn't show much in genetic studies as they are long-lived trees. I myself wonder about Vicia palaestina (whose stub I created). What makes this hard to tease out is that if it occurred, it occurred in the same area as the successful domestication events, thus masking the clues. Abductive ( reasoning) 06:16, 21 June 2024 (UTC) reply

If you are interested in genetics, please see Wikipedia:External links/Noticeboard#Human mitochondrial genetics and share an opinion about whether the proposed ==External links== would be interesting or valuable to readers. WhatamIdoing ( talk) 22:50, 20 June 2024 (UTC) reply

June 21 Information

How high (in angle) do noctilucent clouds have to be to be seen? Do they have to appear outside the lighter area of the sky during nautical twilight? I've been watching clouds before last few sunrises but I'm not sure if i'm just observing high altitude cirruses, they are whitish but not bright at all like in the pictures. Other (lower) clouds stay dark for a long time after that, almost until sunrise. I can't tell if they disappear after sunrise because there's a lot of humidity haze or maybe still Sahara's smog, and my phone is terrible at taking pictures at twilight. Please don't just tell me to read the page, it hasn't helped me with this. 31.217.31.107 ( talk) 02:21, 21 June 2024 (UTC) They were visible from around 3.30 to 4.30 here (30min ago) in Zagreb, whatever they are. They weren't that sharp like on the pictures. 31.217.31.107 ( talk) 02:57, 21 June 2024 (UTC) reply

Under the right conditions you should be able to see them at any angle, wherever they are hanging out, from the horizon to directly overhead.  -- Lambiam 05:48, 21 June 2024 (UTC) reply

I saw them at up to 45 degrees up (the 'height' of the polar star here). They didn't really look like the pictures in the article, they were more faint and blurry although they were lighter than the sky all along while low clouds are darker than the sky that close to sunrise. I think they could look that way because of heavy light pollution lately and high humidity but I'm still not sure if they weren't just cirruses because low clouds are always lighter than the sky near midnight, there's enough light pollution. Is there any way to be sure? 31.217.31.107 ( talk) 05:58, 21 June 2024 (UTC) reply

On the only occasion I've seen noctilucent clouds, they were up to 4 degrees above the horizon (half the altitude of Capella at that time), almost straight north. At the same time, the sun was also almost straight north, 14 degrees below the horizon. Not nautical twilight, but the sky was still fairly bright and the noctilucent clouds were in the bright part. With those angles, the radius of the Earth and some high-school geometry, you should be able to calculate the minimum altitude of the clouds to be in sunlight. If that's more than about 12 kilometres, they can't have been ordinary cirrus clouds. Use a planetarium program like Stellarium (open source) to find the position of the sun at the time you observed the clouds. PiusImpavidus ( talk) 08:11, 21 June 2024 (UTC) reply

A lunar standstill is supposed to happen tonight. I've read the article's simplified description and I'm still confused. So, is this correct? In my own words...

During a lunar standstill, the Moon does not actually stand still, nor does it appear to. All this means is that tonight the Moon will rise at its most northeastern point and set at its most northwestern point. Period. It's not something you can go out at a specific time to observe, see something different, the event ends, and you go about your evening. It's an event that takes "all" (air quotes) night (the time the moon is out).

Do I have that right?

Thanks! † dismas†| ^(talk) 12:14, 21 June 2024 (UTC) reply

I wasn't aware of this, this is quite interesting (if you're into that sort of thing). "Standstill" refers to (the lack of) motion in declination, i.e. the north-south coordinate (equivalent to latitude on earth), and is equivalent to the solstices. Summer solstice was yesterday (sun at its northern-most point), we also have full moon tonight, and since the full moon is opposite to the sun this means that moon is at its southern-most point (not northern!). In addition the moon is at its lowest point below the ecliptic, so that in sum we have a major lunistice. In principle these are all point events but the changes over the course of a night are so small that it is effectively an all-nighter. Where I am, the moon will only be 12 degrees above the horizon when it culminates in the south around midnight. -- Wrongfilter ( talk) 13:31, 21 June 2024 (UTC) reply

According to this article, we're not at the absolute extreme tonight, though. The situation is quite complicated and the extremes differ for moonrise and moonset, compare the graphics in that article. -- Wrongfilter ( talk) 13:44, 21 June 2024 (UTC) reply

For about one year every 18.61 years your hometown Moon rise/peak/set paths are more extreme than any other time (north/south, rises and sets unusually left/starboard, also low/high if you're between latitudes 29 and 62 or so. North or south of 29 you'll never see a shorter hometown Moon shadow than one of these fortnightly standstills in the next year or so probably near one of the standstills near a half moon near one of the next 2 equinoxes (the Full Moons can be up to 1.2 Moon radii less extreme but the c. 19 year cycle is 20 radii to minus 20 radii) Sagittarian Milky Way ( talk) 14:01, 21 June 2024 (UTC) reply

The cycle peaks early 2025 I believe but cause complexities records can be up to seasons away. Records like rightmost Full Moon rise for your location between about 2006 and 2043 or lowest Full Moon path of a night in that timeframe, might be tonight or about 355 days in the future. High Full Moon records are probably December 2024, some other records are probably near an equinox in 2025 or late 2024. If you want I can get each major record to the nearest millisecond (false precision?) for any location on Earth. From what might be the most accurate possible way ( https://ssd dot jpl dot nasa dot gov/horizons/app.html#/, there's also other interfaces like email and telnet but for this you don't need the relatively few email/telnet-only tools) Sagittarian Milky Way ( talk) 14:27, 21 June 2024 (UTC) reply

From 74W 40¾N 0ft the highest Moon center in the future of anyone alive is 77.753639° the year 2025 April 3rd 6:05:02.857pm (ellipsoidal coordinates). The highest before that was 2006 Mar 7th 18:56:52.857 77.753848°. The sky was pretty dark for this one as it's always near half moon so can't be too close to midnight. The highest before that was 1950 October 3 6:07:53.010am 77.782823°. These follow the obliquity Milankovitch cycle which is slow enough that a new record doesn't happen every 18.61 year cycle as you go back in time. So the highest since about 3X thousand BC was about 10,000 years ago. Sagittarian Milky Way ( talk) 21:19, 21 June 2024 (UTC) reply

From Earth's center the northernmost Moon of Oct 2006 to Aug 2043 inclusive is March 7 2025 15:56 UTC 28°43.0'N. Thus longitudes of about 45E will get a slightly more northern Moon record than any other place on Earth. Sagittarian Milky Way ( talk) 17:25, 22 June 2024 (UTC) reply

The cycle is dependent on the longitude of the ascending node. This book [3] says the longitude of the ascending node (☊) = ☊_o - 0.0529539D_e, where ☊_o is the ecliptic longitude of the ascending node at the standard epoch J2000 and ☊ is the ecliptic longitude of the ascending node after D_e (an interval measured in days). The ecliptic longitude of the ascending node at the standard epoch (12h 1 January 2000) was 125.044522°.

Now, the major standstill occurs when the longitude of the ascending node is 0°, which means that the total movement since J2000 is 360° + 125.044522° = 485.044522° (remember the movement is backwards). The number of days since J2000 is therefore 485.0422522/0.0529539 = 9159.750689 days. 24 years contain 8766 days, so the standstill occurs (9160 - 8766) = 394 days after 1 January 2024, or around 29 January 2025. I have just found out that the calendar of golden numbers (mentioned on the Reference desk from time to time) is (or was) mentioned elsewhere in Wikipedia, and the text given there has been augmented to embrace the matters raised here:

LUNAR CALENDAR 1 MARCH 1900 - 28 FEBRUARY 2200

The lunar date for 29 February of a leap year is normally the same as that of the preceding day - thus the lunar date for 28 and 29 February 2028 is 3 Ronan. For use of the letters A - g to find the day of the week see Dominical letter. The months are: (1) Harriet, (2) Ronan, (3) Miri, (4) James, (5) Eloise, (6) Thomas, vii, (8) Nicholas, (9) Catherine, (10) Richard, (11) Emma, (12) Paul. Paul II, a 30-day month, is added between Paul and Harriet 7 times in 19 years. When the golden number is 19, Richard has 29 days instead of 30. See Saltus#Latin (third bullet point).

The numbers move down one day on 1 March of years which, although divisible by four without remainder, are not leap years. They move up one day eight times in 2500 years. The next eight movements will be on 1 March of 2100, 2400, 2700, 3000, 3300, 3600, 3900 and 4300. Sometimes the movements cancel out - thus in 2100 the numbers stay where they are. The numbers mark the first days of the lunar month. Each year's golden number is found by adding 1, dividing by 19 and taking the remainder. If the remainder is 0, the golden number is 19. Until 2099 Orthodox Easter falls from 19 - 25 Miri, on whichever day is Sunday. From 2100 to 2399 the range is 20 - 26 Miri, and so on. So to find Orthodox Easter in 2025:

2025 + 1 = 2026. 2026/19 = 106 remainder 12. From table, 1 Miri is 31 March. The Sunday letter is E. 20 April (21 Miri) is an "E" day. Orthodox Easter is 20 April.

To calculate the date of occidental Easter, proceed as follows:

1. In the calendar, locate the date of 14 Miri

2. If 14 Miri falls on or before 17 April, Easter is the Sunday following. If 14 Miri falls on 18 April and no golden number is marked against 6 April, again Easter is the Sunday following. If 14 Miri falls on 18 April and a golden number is marked against 6 April, Easter falls on 18 April (if Sunday), and if 18 April is not Sunday Easter falls on the following Sunday.

3. If 14 Miri falls on 19 April, Easter falls on 19 April (if Sunday), and if 19 April is not Sunday Easter falls on the following Sunday.

4. If 14 Miri falls on 20 April or later, the date is to be treated as a day of March, and Easter falls on the day after the Saturday following that date.

The calendar may be used to locate the moon at any given time.

Example

It is 9 PM Greenwich Mean Time in London on 15 February 2024. The golden number is 11, which is printed against 11 February. This is the lunar new year (1 Harriet) and 15 February is therefore 5 Harriet. At the end of the previous month (as at the end of every lunar month) the sun and moon are together in the sky, but the lunar day is on average 4/5 hour longer than the solar day. Thus at 9 PM it is only 5 PM by the moon. Whether the moon is visible at that time may be determined using the fact that the moon moves through the zodiac at the rate of 13.2° per day (compared to 1° per day for the sun). On 15 February (5 Harriet) the moon will have advanced (5 x (13.2 - 1)) = 5 x 12.2 = about 61° ahead of the sun. So it will be where the sun will be about 61 days later, i.e. around 16 April.

But there is another factor. The moon's ascending node (where the plane of its orbit crosses the ecliptic in a northerly direction) moves backwards, completing a circuit relative to the equinox in 18.6 years. When the longitude is 0° (which it will reach around 29 January 2025) it reaches a maximum of 5° further from the celestial equator than does the sun (the major standstill). Half a revolution later (the minor standstill) it reaches a maximum of 5° nearer to the celestial equator than does the sun.

So considering the moon's position at 9 PM on 15 February 2024 we look whewre the sun would be at 5 PM on 16 April and (since the date is fairly close to the major standstill) a little higher in the sky. The moon was thus looked for (and was seen) high in the west.

The "establishment" of a port is the number of hours high tide is reached there after the moon crosses the meridian (i.e. 12 noon or midnight by the moon). The state of the tides may thus be predicted using the method above, remembering that tides are highest at the middle and the end of the lunar month ("spring tides") and their amplitude is greatest at the equinoxes. For accurate predictions consult specialist tables.

June 22 Information

Several questions: (1) Can a Boeing 707-120B take off at MTOW from Runway 04/22 at Greater Rochester International Airport? (2) How much payload (if any) would have to be taken off for the same jet to take off from Runway 10/28 at the same airport, with a 45-knot headwind and below-freezing temperatures as would be the case in a severe blizzard (and would this be possible at all)? (3) How much payload (if any) would have to be taken off for said Dash-120B to fly nonstop from ROC to Rome Fiumicino Airport with acceptable reserve fuel remaining, assuming no tailwinds along the route (and would this be possible at all)? (Questions inspired by the original Airport movie.) 2601:646:8082:BA0:649B:7753:3C84:C70D ( talk) 12:27, 22 June 2024 (UTC) reply

1: According to the official documentation from Boeing, if it's equipped with the original JT3D-1 engines, the takeoff runway length requirement at 500 feet above sea level, standard temperature and maximum take-off weight is 8500 feet. Those Boeing documents are in US units. Your runway is 8001 feet, so it won't fit. At least, not with the proper safety margin. If equipped with the more modern JT3D-3 engines, the takeoff runway length requirement is 7800 feet, so that fits.

2: Under normal circumstances, assuming JT3D-3 engines, maximum weight on a 6400 foot runway is 232,000 pounds, 26,000 pounds below MTOW. Freezing temperature would take the density altitude down to below sea level, which the documentation doesn't tell about, so I'll assume sea level. The 45 knot headwind reduces takeoff groundspeed to about 70% and required runway length to a bit more than 50% of the original, so about 4000 feet should be enough, even at MTOW. Unless there's snow on the runway. Ploughing through snow may increase drag enough that it can't take off at all, but it also reduces braking performance, so you need more length for an aborted takeoff.

3: The distance from ROC to Fiumicino is 3780 nautical miles. Taking off at MTOW, it can carry a payload of 25,000 pounds, assuming JT3D-3 engines and a standard cabin configuration. This is slightly less than a full payload of 137 passengers and baggage, 28,000 pounds. Maximum payload for short flights is 42,000 pounds, passengers, baggage and cargo. PiusImpavidus ( talk) 09:54, 23 June 2024 (UTC) reply

OP: Why did you choose Rochester? Airport_(1970_film) is set in Chicago, so wouldn't O'Hare International Airport or Midway International Airport be a better reference? RudolfRed ( talk) 18:24, 23 June 2024 (UTC) reply

Because I'm doing some very early work on a rescue simulator game, so for this mission I wanted to move the departure airport further east so as to speed things up (it wouldn't do to have some of the players, in particular the one playing the medic, sit around for 2 hours or more doing nothing) -- but I see this probably won't work, so I guess I'll go with Boston Logan Airport instead (I had rejected it at first because I thought it would have sped things up too much, but on second thought it wouldn't be the case because the flight would be flying parallel to the shore at first). Not happening any time soon, though -- for one thing, a simulator would be way over my head at this point (and I'd have to put together a whole studio, because it's far too much work for just one person, no matter how highly skilled), and also for this particular mission I'd have to first get permission to use the likenesses of Dean Martin, Jacqueline Bisset, Helen Hayes and Van Heflin as Vernon Demerest, Gwen Meighen, Ada Quonsett and D.O. Guerrero respectively! 2601:646:8082:BA0:649B:7753:3C84:C70D ( talk) 21:34, 23 June 2024 (UTC) reply

And there was me thinking you meant Rochester Airport, which is certainly further east. Alansplodge ( talk) 14:56, 24 June 2024 (UTC) reply

I'll admit to having to read the original comment twice. The thought of a 707 attempting to take off from Rochester Airport's 2,000 feet (610 m) grass strip is a bit alarming! Martin of Sheffield ( talk) 09:04, 25 June 2024 (UTC) reply

Hi. Some motor drivers have an energy saving feature; for example, in the TMC2209 [4] it's called "CoolStep".

I'm guess that this is accomplished via some very clever control circuitry inside. For example:

1. if a stepper is holding its position, and there's 0 load on it (just a bare stepper motor sitting on a desk connected to a TMC2209), then 0 current is needed

2. if I use my finger to try to turn the stepper shaft, a back EMF is generated in the stepper. The TMC2209 senses this voltage, and supplies a current in the opposite direction to counteract it

3. as a result, my finger will feel a "torque" from the stepper, and the stepper will hold its position, despite my applied force

(This is my best understanding of how it works.)

Is it possible to apply this same technique, or an analogous technique, to drive a solenoid?

I'm asking because the two situation are almost analogous to each other:

A. a solenoid is connected to a solenoid driver. A permanent magnet is stuck to the solenoid via magnetic force. There is 0 movement, so 0 induced voltage. There is 0 force, so 0 current is needed to hold this position

B. if I use my finger to try to move the magnet, a back EMF is generated in the solenoid. The solenoid driver senses this voltage, and supplies a current in the opposite direction to counteract it

C. as a result, my finger will feel a "force" from the solenoid, and the magnet will hold its position, despite my applied force

Is this kind of control actually possible in reality? In my head, I'm imagining something like this is possible in theory, but I don't know enough electronics to know whether it's actually possible or not.

Is there any commercial solenoid driver that can accomplish the above described power-saving feature? I could not find any myself. Since manufacturers use different marketing terms (such as "CoolStep") to describe their proprietary technology, it's possible that such a driver exists, but I don't know the right keyword to search for so I cannot find it. OptoFidelty ( talk) 21:24, 22 June 2024 (UTC) reply

The TMC2209 Datasheet says thatCoolStep's operation relates to the StallGuard4 feature, which it describes as being based on back-EMF. But "CoolStep is not able to measure the motor load in standstill and at very low RPM". One application of sensing linear motion and counteracting it (effect: holding something in approximate position with minimal required force) is damping...lots of ways of implementing it. DMacks ( talk) 21:53, 22 June 2024 (UTC) reply

Is there any commercially available IC that can achieve this damping effect?

I'm guessing that there are at least a dozen solenoids any new car, so presumably they have some very smart solonoid drivers inside them to control the drive current.

Currently I'm just using a constant current to drive the solonoid, which is very wasteful, since 99% of the time, 0 current is needed. I don't know how to achieve this back-EMF sensing feature on my own.

It'd be helpful if I can find a commercially available solonoid drivers IC that has this feature built-in. OptoFidelty ( talk) 22:48, 22 June 2024 (UTC) reply

Not my field (ha!), sorry. DMacks ( talk) 02:39, 23 June 2024 (UTC) reply

No worries. Thank you for the help so far.

At least I know it's physically possible now. Just not sure where to find any commercial solutions for it, if such a thing exists. OptoFidelty ( talk) 06:40, 23 June 2024 (UTC) reply

The back-EMF gives a velocity sensor. Holding a position with only a velocity sensor is possible with a perfect sensor, but in reality sensors aren't perfect and some creep will happen – which is why the example mentioned above doesn't work in standstill. You need a position sensor, or apply a brake. PiusImpavidus ( talk) 10:17, 23 June 2024 (UTC) reply

June 23 Information

${\displaystyle X_{total}=X_{initial}+X_{additional}}$

Where the ${\displaystyle Xs}$ are physical properties of the same type (e.g. of energy, or of electric charge, and likewise).

Those physical properties don't have to be denoted by the same letter in the formula.

They should be denoted by not more than three letters, excluding indices if needed.

The indices: "total", "initial", "additional", mentioned above, don't have to be mentioned in the formula, either. They should be understood, though, from the standard meaning of the letters/indices mentioned in the formula. Therefore, formulas of the type ${\displaystyle E_{total}=E_{potential}+E_{kinetic}}$ should be ignored, because none of those Es (=energies) is usually interpreted as "initial".

"Initial" can also mean "basic".

HOTmag ( talk) 10:59, 23 June 2024 (UTC) reply

What about integrations, eg the amount of electric charge on an object = integration over time of the current flowing through a surface that encloses the object.? (+ initial charge) Graeme Bartlett ( talk) 11:21, 23 June 2024 (UTC) reply

I even avoid simpler formulas, e.g. of the type ${\displaystyle X_{total}=X_{initial}+YT,}$ not to mention ${\displaystyle X_{total}=X_{initial}+\int Ydt.}$ HOTmag ( talk) 12:05, 23 June 2024 (UTC) reply

Is Mass–energy equivalence#Low-speed approximation one of the "useful" formulas by your definition, as applied to the Parker Solar Probe? Mike Turnbull ( talk) 14:19, 23 June 2024 (UTC) reply

Your example uses too many letters. I must use three only (the Xs), and all of them should be of the same type, as indicated above. HOTmag ( talk) 16:03, 23 June 2024 (UTC) reply

That's a distinction without a difference. Just call it X_displacement if the letters Y and T offend you. DMacks ( talk) 21:30, 23 June 2024 (UTC) reply

Why can YT offend me? Because it also means YouTube? HOTmag ( talk) 06:59, 24 June 2024 (UTC) reply

"Where the ${\displaystyle Xs}$ are physical properties of the same type" - they have to be for the equation to make sense. see Dimensional Analysis. i can't off hand think of a non trivial equation that is simple enough for your requirements. weight_today=weight_yesterday+change_in_weight_per_day? Greglocock ( talk) 22:16, 23 June 2024 (UTC) reply

They have to be [of the same type], for the equation to make sense: Yes, of course. I'd only wanted to exclude hypothetical examples meaning eg: "What I like to talk about = energy + electric charge". Admittedly, it's only a hypothetical example, because it does not reflect any useful formula, whereas what I need should be a useful formula, as indicated in the title. This requirement also excludes your last suggestion. HOTmag ( talk) 06:59, 24 June 2024 (UTC) reply

How about ${\displaystyle m=m_{0}+\delta _{m}}$ from bare mass? -- Amble ( talk) 02:35, 24 June 2024 (UTC) reply

Yes, this is a good example. Anything else? HOTmag ( talk) 06:59, 24 June 2024 (UTC) reply

See equations under Equation_of_time#Mathematical_description such as "EOT = GHA - GMHA" and following. Also see ${\displaystyle h_{\alpha \beta }=g_{\alpha \beta }-\eta _{\alpha \beta }\,.}$ and following at Post-Newtonian expansion. In general, this type of equation comes up when you're trying to split a difficult problem into a larger part, which can be exactly solved, and a smaller part, which can be treated as a perturbation. -- Amble ( talk) 17:10, 24 June 2024 (UTC) reply

Thank you. To me, the time formulas are better than the Post Newtonian expansions, because I need precise equations rather than approximations. HOTmag ( talk) 18:20, 24 June 2024 (UTC) reply

Does it have to be symbolic, or does this count: "When the voltage is increased by 100 volts, the new voltage will be 150 V + 100 V = 250 V" ^[5]?  -- Lambiam 06:52, 24 June 2024 (UTC) reply

As indicated in the title, the example should be a useful formula, so yes it has to be symbolic. HOTmag ( talk) 06:59, 24 June 2024 (UTC) reply

June 24 Information

We know that:

The color sequence of stars is that M stars are red, K=orange, G=yellow, F=yellowish white, A=white, B=bluish white, and O=blue. The sun is a G star. But I keep hearing that the sun is white. Does a correction need to be made?? is G really white (as opposed to A being white that we learn from this sequence)?? Georgia guy ( talk) 01:43, 24 June 2024 (UTC) reply

See stellar classification, particularly the section on conventional colour description. The peak spectrum of the Sun is around yellow. As far as we are concerned using our eyes the Sun is white. As far as astronomers using instruments are concerned, it is slightly yellow. Hotter stars are comparatively bluer, and cooler stars are comparatively redder. Stars are so bright that each one at the same apparent luminosity will appear as a shade of white tinged with something else, at least for humans that evolved under the Sun's particular spectrum. What we call a "red" star, i.e. Betelgeuse, is only red by comparison - it's really kind of pink as far as we're concerned, and that's kind of an extreme example. Acroterion (talk) 01:51, 24 June 2024 (UTC) reply

The Sun is white because, almost per definition, white is the colour of the visible spectrum of the light emitted by our sun. Snow is white because it reflects this light uniformly.  -- Lambiam 05:51, 24 June 2024 (UTC) reply

Colour perception can be weird. Some observers see Beta Librae (Zubeneschamali) as green, even though that shouldn't be possible since green is in the middle of the visible spectrum. Double sharp ( talk) 07:31, 24 June 2024 (UTC) reply

The sun is, to our eyes, white, more or less by definition. The white balance of our eyes automatically adjusts itself to the colour of ambient light and the sun provides most of our ambient light, making sunlight white.

Astronomers usually express colours in a number, not a word. You take the magnitude of an object as measured through a particular colour filter, do it again through a different filter and find the difference. Magnitudes are logarithmic, so this is the logarithm of the ratio of brightnesses in two wavelength bands. See colour index. Traditionally, magnitudes are calibrated such that the magnitude of Vega is zero in every band. That makes the colour index of Vega, an A0 star, zero. If you say that a colour index of zero means white, than Vega is white and the Sun is yellow. But as every photographer knows, there's no absolute truth in white balance.

Not all stars have a spectrum close to a black body. Strange colours do occur. PiusImpavidus ( talk) 10:27, 24 June 2024 (UTC) reply

Interesting. Phil Plait explains Beta Librae along those lines in one column, noting that it is a young star and a rapid rotator. Double sharp ( talk) 12:26, 24 June 2024 (UTC) reply

I haven't seen anyone mention that the reason we think of the Sun as "yellow" is that this is its color when it's low in the sky (but not low enough to be orange), and when it's higher than that, we can't (and definitely shouldn't) look at it for more than a split second. However if there's a bit of cloud cover that you can view the Sun through (at your own risk!) higher in the sky, you'll see it as white.

Now, to be honest, I don't have a source for that being the reason. But it does seem pretty obvious. -- Trovatore ( talk) 00:51, 25 June 2024 (UTC) reply

There's probably a discussion about that somewhere, but yes, the only time humans can safely examine the sun and assess its color, even for an instant, is when it's low on the horizon and yellow, orange, or red according to atmospheric conditions, and because we associate warm colors with, well, the warmth of the sun. There's also a lot of yellow sun cultural baggage that starts in preschool - ask a child to draw the sun and they'll reach for the yellow crayon. And as PiusImpavidus notes, white balance is what we decide it is."Daylight" light bulbs that mimic the sun's color temperature appear distinctly blue to humans used to orangey domestic lights. Acroterion (talk) 12:07, 26 June 2024 (UTC) reply

I mean, you probably shouldn't replicate this experiment, but FWIW, the midday sun looked white to me when I accidentally glanced at it. :) Double sharp ( talk) 14:49, 26 June 2024 (UTC) reply

I heard that, although we usually think that Human intelligence (or at least human-like) is exclusive of humans, other species of hominids were also capable of it. The best known one, the Neanderthal. They are extinct, so human-like intelligence is exclusive of us now, but not in the history of evolution.

But which are, then, the specific species that developed such intelligence, as opposed to being just very smart animals? Hominidae is clearly not, as gorillas and chimpanzees are not in that level. Is it Homo? Is it Archaic humans? Are either of those composed only of intelligent creatures, excluding non-intelligent ones, or are they groups of related species regardless of intelligence? Cambalachero ( talk) 02:51, 24 June 2024 (UTC) reply

Neanderthals are an archaic human species; Homo is a genus including modern and archaic humans. Intelligence is a concept that is very hard to define. Human intelligence arose in a long process of evolution; it is impossible to point out a specific point where the intelligence of our progenitors became "human", both because this did not leave a traceable paleoanthropological record and – more importantly – because it is not possible to define the boundary between "pre-human intelligence" and "human intelligence". For the little that is known, see Evolution of human intelligence.  -- Lambiam 04:30, 24 June 2024 (UTC) reply

I have seen conflicting claims about whether the domestic cat descends from the European Wildcat or from the African Wildcat. Cat#Evolution shows two phylogenies: one (based on analysis of nuclear DNA) which shows the domestic cat being most closely related to the European Wildcat (and the Domestic/European Wildcat group being a sister group of the African Wildcat/Chinese Mountain Cat). The other (based on mitochondrial DNA) shows the domestic cat being descended from the African Wildcat. What does this actually mean? Is it just a case of "data from different sources is contradictory and we haven't got a conclusive answer yet"? Or does it mean that domestic cats are descended from male European wildcats that mated with African females? Or something else? Iapetus ( talk) 12:07, 24 June 2024 (UTC) reply

Well mitochondrial DNA is inherited from the mother, so it means that the mother of the mother of the mother of the mother of the mother of the mother ..... of a domestic cat is an African wildcat. Many other ancestors could be European wildcats. Can these two kinds of wild cat interbreed? Graeme Bartlett ( talk) 22:48, 24 June 2024 (UTC) reply

Yes. 2A0D:6FC0:84F:DF00:30E3:AD05:B7F9:443A ( talk) 23:45, 24 June 2024 (UTC) reply

Both phylogenies can be brought into agreement in the following scenario. African wild cats were domesticated. It seems plausible that cats were first domesticated in Egypt or thereabouts. These domesticated African cats were brought to Europe and interbred with wild European cats. When a male domestic cat interbred with a female wild cat, the hybrid offspring was born in the wild and, being hybrid, was not so likely to survive, keeping the European wild cat distinct from the African wild cat. When a female domestic cat interbred with a male wild cat, the hybrid offspring was born in captivity and likely to survive as a domestic cat, making the European domestic cat evolve towards the European wild cat, whilst keeping the African mitochondrial DNA.

There's also selection pressure on domestic cats, keeping them distinct from European wild cats. PiusImpavidus ( talk) 11:25, 25 June 2024 (UTC) reply

However, in the UK (where latterly the species has only survived in Scotland) the population of Scottish wildcats has significantly hybridised with domestic cats. Active breeding and re-introduction programs are taking place to counter this. (The poster foremrly known as 87.81.230.195} 151.227.226.178 ( talk) 16:08, 25 June 2024 (UTC) reply

I have a bottle of 50 ml with cypermethrin. The instructions by the manufacturer say diluire al 2-3% in acqua. Do they mean I must dilute it to a 2% to 3% solution (for example mix with 2 liters of water which will give a 2.4% to 2.5% solution)? Thank you. Hevesli ( talk) 17:24, 24 June 2024 (UTC) reply

Yes you could do it that way. But if you don't want to use 2 litres of solution you could mix less, say half of it in 1 liter or 1 ml in 50 ml of water. Graeme Bartlett ( talk) 22:51, 24 June 2024 (UTC) reply

I have heard that the moon is upside down in Australia but I don't know if the sun is also upside down in Australia. Can anyone tell me because I am curious. 2001:8003:429D:4100:20F0:744E:F9F2:D791 ( talk) 23:10, 24 June 2024 (UTC) reply

If you check out the angle of the person on the Earth, say from someone at 45° north going to someone 45° south, the difference is 90°, so the appearance is sideways on. But from north pole to south pole it is rotated a full 180°. But at the poles it will be hard to see the sun from both at the same time. With the Sun it is harder to see it is rotated or not, as normally you won't be able to see any detail on the sun. With sunspots your could see something with the right equipment. But not only movement around the Earth will rotate the view of the sky, looking at moonrise and moonset will see that the moon has rotated in the sky for you. The same will apply to the Sun. Graeme Bartlett ( talk) 23:51, 24 June 2024 (UTC) reply

Twice per year on the Equinox the Sun can be seen on the horizon simultaneously from both the North and South poles. Philvoids ( talk) 17:54, 25 June 2024 (UTC) reply

Above the horizon as the centers will be 8 to 9 angular seconds below the horizon (parallax) but mean upward refraction is 34 angular minutes at the horizon it'd have to be less than half Earth average refraction for the circa 16 angular minute tall lower half to not clear the horizon. If the horizon isn't flat perhaps from icebergs it would be harder. Sagittarian Milky Way ( talk) 22:17, 25 June 2024 (UTC) reply

Regarding the moon being "upside down", it depends how you're standing when you're looking up at it. The natural thing to do is to look up at the narrower angle. But if you turn around (and have something to lean back on or are very well balanced), you can look up at it at a wider angle, and it will appear the way someone in the opposite hemisphere would normally look up at it. And I would think the same would apply to the sun. ← Baseball Bugs ^{What's up, Doc?} carrots→ 00:37, 25 June 2024 (UTC) reply

When somebody is looking south at some object in the sky from Japan, and somebody else is looking north at the same object from Australia, the object will appear upside down for the person from Australia, because that person is upside down compared to the one in Japan. It doesn't matter what you're looking at: Moon, Sun, constellations, planets, alien spaceships... PiusImpavidus ( talk) 11:36, 25 June 2024 (UTC) reply

• Neither person is "upside-down" compared to the other. Tokyo, for instance, is about 7,800 km from Sydney. That's just under 1/5 of the Earth's circumference, so the two people are oriented about 72° apart, not 180°. -- 142.112.148.225 ( talk) 19:08, 25 June 2024 (UTC) reply

  This is bullshit. At sunrise or sunset on an equinox it's about 72° Sydney latitude vs Tokyo latitude same longitude but at noon on a sundial all other places same longitude will be 180° so long as the Sun's declination is between the 2 places. If the 2 latitudes are above 23.44 and below minus 23.44 respectively the Sun's declination will always be in between from now till over 10,000 years from now. Sagittarian Milky Way ( talk) 22:35, 25 June 2024 (UTC) reply

  Projected onto the plane perpendicular to the line Earth–Sun, one is upside down relative to the other. It's fair to make this projection, because either observer projects the orientation of the Sun onto his own vertical. PiusImpavidus ( talk) 07:49, 26 June 2024 (UTC) reply

The image I put up here (not to scale) should make this somewhat intuitive. Imagine that the sunspots happen to make a face, so that an observer sticking their head up at the North Pole sees it "upside up". Clearly, an observer peeking out from the South Pole will then see it upside down.  -- Lambiam 12:49, 25 June 2024 (UTC) reply

That's very helpful; thank you. I've long known of the phenomenon, but always struggled to picture it. Matt Deres ( talk) 17:33, 26 June 2024 (UTC) reply

June 25 Information

Such as light carrying an infinite wavelength, i.e. zero-frequency, i.e. zero-momentum, i.e zero-energy, and the like. For the time being, I'd like to ignore the property of velocity.

Is there any evidence of such irregular properties of any light? If no evidence, then what about any theory mentioning this kind of irregular properties of light, as a hypothetically possible option? Maybe when light unsuccessfully tries to escape a black hole? HOTmag ( talk) 00:32, 25 June 2024 (UTC) reply

Weird stuff with light: Caustic (optics); Photon sphere; Atmospheric ghost lights, Fata Morgana (mirage); Electromagnetically induced transparency which also covers stopped light; Orbital angular momentum of light. Also Unruh effect where light appears if acceleration is great enough. Graeme Bartlett ( talk) 09:34, 25 June 2024 (UTC) reply

Thank you. Do your examples include information about light carrying an infinite wavelength, i.e. a zero-amplitude, i.e. a zero-frequency? Please see my thread below. HOTmag ( talk) 10:38, 25 June 2024 (UTC) reply

If zero-energy photons (or any zero-energy particles) exist, there is no way to detect them. If you think of particles as being an excited state of a quantum field, zero-energy particles are obviously not excited, so they are in fact not real particles.  -- Lambiam 10:28, 25 June 2024 (UTC) reply

Technically speaking, you are right. But please see my thread below. HOTmag ( talk) 10:38, 25 June 2024 (UTC) reply

Our article Renormalization points out:

Every process involving charged particles emits infinitely many coherent photons of infinite wavelength, and the amplitude for emitting any finite number of photons is zero.

Do those hypothetical photons of infinite wavelength, i.e. of zero-amplitude, i.e. of zero-frequency, have a name? Is there any article where I can read about them? HOTmag ( talk) 10:35, 25 June 2024 (UTC) reply

static electricity or magnets have an electromagnetic field with 0 frequency. Probably not the answer to your question though. Graeme Bartlett ( talk) 10:57, 25 June 2024 (UTC) reply

The adjective evanescent describes an oscillating electric or magnetic field that propagates as an electromagnetic wave but has its energy spatially bound in the vicinity of its source. Philvoids ( talk) 11:55, 26 June 2024 (UTC) reply

For example, at the Pourbaix diagram beside, there is a borderline between Fe³⁺ and FeO2−4. Can a solution at that border be considered a solution of [Fe³⁺₂[FeO2−4₃, and if yes, can this salt be isolated?

More generally, if a cation and an anion touch in a Pourbaix diagram, do they form a salt? Nucleus hydro elemon ( talk) 11:17, 25 June 2024 (UTC) reply

In this case it could not be the compound you suggest, as ferric oxide in itself is not alkaline enough to make the ferrate. So there would have to be some extra alkali around. On the line it could be either of the species from 0% to 100% and not necessarily in a 3:2 ratio to balance the charge. The charge is balanced by something like Na⁺ ions. In general it may be balanced by ions derived from water OH⁻ or H⁺. Graeme Bartlett ( talk) 11:56, 25 June 2024 (UTC) reply

Admittedly, I know I could simply say "photon" without adjectives, because if it had already been absorbed then it would no longer be a photon, but I still wonder if there's any direct adjective expressing more precisely the very fact - that this photon is still free - in the above sense. I think the term "free" photon is not sufficient. Maybe "unabsorbed" photon? HOTmag ( talk) 16:05, 25 June 2024 (UTC) reply

@ Philvoids:Yes, I know that, but how does it answer my question? Have I ever claimed bosons and fermions belong to the same category? I asked about photons only, rather than about their whole category. HOTmag ( talk) 19:43, 25 June 2024 (UTC) reply

You can say "propagating photon". Ruslik_ Zero 20:17, 25 June 2024 (UTC) reply

You could say "existing photon" (versus a no-longer-existing photon or a not-yet-emitted photon), but really, as you admit yourself, there's no need for such an adjective, so no such adjective is in common use. PiusImpavidus ( talk) 07:59, 26 June 2024 (UTC) reply

June 26 Information

So, I ran out of lime juice (containing citric acid) while cooking some fish, and started wondering if there were any easily obtainable/ common substitutes. Obviously vinegar (containing acetic acid) goes with fish, but it probably doesn't go with vodka and diet coke to reduce the sweetness (I haven't actually tried that yet). So I wondered how chemically similar citric and acetic acids are. I have a very basic knowledge of chemistry, (I scraped a C at O-level many moons ago), so please treat me as an interested layman whose lack of even fundamental mathematics at the time sadly prevented me from becoming an organic chemist.

Anyway, I started off with organic acids, where the lede lists some common carboxylic acids, but they don't seem to be in any sort of order.

• Lactic acid
• Acetic acid
• Formic acid
• Citric acid
• Oxalic acid
• Uric acid
• Malic acid
• Tartaric acid
• Butyric acid
• Folic acid

(Answer, I think: Citric and acetic acids are somewhat alike, but only up to a point, Lord Copper). With some further hunting, I wondered about arranging the above list in order of complexity, with some extra additions: I hope I have got everything right. This exercise gave rise to some questions, included in the entries: I wonder if anyone could help me with these, please?

• Carboxylic acids (one carboxyl COOH group)
  • Formic acid CH₂O₂ (Question 1: why is it not written HCOOH like oxalic acid below?)
  • Acetic acid CH₃COOH
  • Butyric acid C₃H₇COOH, alternatively CH₃(CH₂)₂COOH (not in list)

• Alpha hydroxycarboxylic acids (one COOH group plus hydroxyl group separated by one C atom)
  • Lactic acid C₃H₆O₃
    • Glycolic acid C₂H₄O₃ (not in list) (Question 2: The list in Omega hydroxy acid#List includes it as matches the formula pattern C_nH_2nO₃. To which classes does this pattern refer, like the alkanes match C_nH_2n+2?)

• Beta hydroxycarboxylic acids (one COOH group plus hydroxyl group separated by two C atoms)
  • Salicylic acid C₇H₆O₃ (not in list)

• Dicarboxylic acids (two COOH groups)
  • Oxalic acid H₂C₂O₄, or alternatively (COOH)₂ - (Question 3: Why H₂ first and not C₂? See Q. 1)
  • Malic acid C₃H₄O₄
  • Malonic acid C₄H₆O₅ (not in list)

• Tricarboxylic acids (three COOH groups)
  • Tartaric acid C₄H₆O₆, alternatively HO₂CCH(OH)CH(OH)CO₂H
    • Aconitic acid C₆H₆O₆ (not in list)
  • Citric acid C₆H₈O₇, alternatively HOC(CO₂H)(CH₂CO₂H)₂
    • Isocitric acid C₆H₈O₇ (not in list)- (Question 4: How can it be both a tricarboxylic and an Alpha hydroxycarboxylic acid? Is one a subset of the other?)
    • Agaric acid C₂₂H₄O₇ (not in list)

• Not sure:
  • Uric acid C₅H₄N4O₃
  • Folic acid C₁₉H₁₉N₇O₆ - in Category:Dicarboxylic acids, otherwise no mention of it being one in the article. (Question 5: are they both really carboxylic? Are they not heterocyclic nucleic acids?)
  • (Question 6: How many of these groups in main bullet points match a formula pattern like C_nH_2nO₃?)

Thanks for your patience, cheers, > MinorProphet ( talk) 12:49, 26 June 2024 (UTC) reply

Food-grade lactic acid and tartaric acid are used to give a sour taste to foods and drinks, so they are clear candidates for being tried as substitutes. If you happen to have unripe grapes or plums, you could use their juices.  -- Lambiam 16:28, 26 June 2024 (UTC) reply

Malic acid gives the tart taste to plums and many other fruits, as well as rhubarb.  -- Lambiam 09:37, 27 June 2024 (UTC) reply

Acetic acid has a strong odour, and so will change the human experience. Many of the acids you listed above are toxic and so either should be avoided or only used in tiny amounts as they occur in foods, eg oxalic acid. Q1: Formic acid can be written written HCOOH. Q2: the pattern you give is for an alkane derive carboxylic acid with extra oxygen. An extra oxygen could go in between carbon and hydrogen so that it is a hydroxy acid, (alpha, beta, omega etc); it could form an ether between two carbons, or it could go next to another oxygen and make a peroxy acid. The alkane base compound could be a linear chain of carbon atoms, or it could be branched. Q3: compounds could be in more than one category, so that if the second carbon is the last, an alpha acid is an omega acid too. Q2: many of these compounds' formulae have been written using Hill notation, which has C first and H second then in alphabetical order. The formula you gave for oxalic acid is not in this form. However it does not matter as there is only one isomer with this combination of atoms. Often the formula can be written in a variety of ways for one compound. Q4: a compound can be in more than one class if it meets the membership requirements or multiple classes. Q5: some compounds are acidic even if they are not carboxylic acids. Folic acid is a dicarboxylic acid. Uric acid can form a tautomer that can lose an H⁺ to make urate. It is not a carboxylic acid. And yes, both of these are heterocylcic compounds. Graeme Bartlett ( talk) 22:58, 26 June 2024 (UTC) reply

For Q2/6, other examples of C_nH_2nO₃ are methoxyacetic acid and peracetic acid Graeme Bartlett ( talk) 23:02, 26 June 2024 (UTC) reply

Strictly speaking, other isomers of oxalic acid are possible. See C₂H₂O₄ search at ChemSpider which gives two others that have associated literature. Our organic acid article is very poor, probably because it is difficult to cover such a broad subject well. If the OP wants to delve deeper, a textbook would be a better place to look. We have recently started to link some on our Project Page at WP:CHEM#Good open access sources and the McMurry one has extensive coverage of organic acids. Mike Turnbull ( talk) 13:20, 27 June 2024 (UTC) reply

Those general formulae above will actually have many more isomers by moving the oxygen or double bond around. But they would not be carboxlic acids any more. Graeme Bartlett ( talk) 00:26, 28 June 2024 (UTC) reply

That's really helpful, thanks all very much indeed for some clear explanations. @Lambiam: would a bit of Cream of Tartar (in the kitchen cupboard) work? Not worried about the possible cloudy effect. @Graeme Bartlett: I wasn't thinking of trying all the acids I listed as lime juice substitutes, I was just hoping to make sense of the list in the Organic acid article. @Mike Turnbull: I found McMurry is also available at archive.org to borrow. Lots to think about. Exits left, clutching tripod, gauze mat, Liebig condenser and Bunsen burner. Favourite quote: Frederick Sanger described himself as "just a chap who messed about in a lab." MinorProphet ( talk) 21:07, 28 June 2024 (UTC) reply

@ MinorProphet That archive.org version is the fifth edition. The latest (10th) edition is the one available at Openstax. You can download .pdf by chapter or get the whole ~190 MB. Mike Turnbull ( talk) 21:22, 28 June 2024 (UTC) reply

Here it is said that the tangy flavor of cream of tartar makes it an excellent addition to marinades, adding acidity and enhancing the taste of grilled or roasted meats. Whether it works in a fish recipe can only be determined experimentally.  -- Lambiam 09:57, 29 June 2024 (UTC) reply

And all this time I've been thinking that Tartar sauce contains some cream of tartar ... Abductive ( reasoning) 05:55, 30 June 2024 (UTC) reply

June 27 Information

1. Why are these maximally symmetric ones "unnatural" but there are major biology omega-3's/6's that start the divinylmethane pattern as little as 1 carbon higher? all-cis-3,6,9-dodecatrienoic acid all-cis-3,6,9,12,15-octadecapentaenoic acid all-cis-3,6,9,12,15,18,21-tetracosaheptaenoic acid. 2. Why does the article stop at hexaenoic? If there's 22:6 shouldn't there be room for 26:7? 3. Would all-cis-2,4,6,8,10-dodecapentaenoic acid melt at lower temperature than all-cis-3,6,9-dodecatrienoic acid, all-cis-2,4,6,8,10,12,14,16-octadecaoctaenoic acid melt at lower temperature than all-cis-3,6,9,12,15-octadecapentaenoic acid and so on? Sagittarian Milky Way ( talk) 00:18, 27 June 2024 (UTC) reply

Sounds like you are interested here in conjugated polyunsturated acids, like α-parinaric acid or α-eleostearic acid. In living organisms, there is danger of lipid peroxidation for these. Graeme Bartlett ( talk) 12:22, 27 June 2024 (UTC) reply

Slightly off-point but readers may like to know that you can do substructure searches over Wikipedia chemistry articles using Wikipedia Chemical Structure Explorer. It takes a bit of getting used to but allows, for example, searching for all divinylmethanes we have articles about. Similar searches can be run at PubChem with, of course, many more hits likely. PubChem will link the hits back to Wikidata if there is an entry here (possibly not an article or one not in English). Mike Turnbull ( talk) 13:38, 27 June 2024 (UTC) reply

According to that there's no ringless unbranched acid on Wikipedia with a double bond at 3, the closest is the very important DHA 22:6 with double bonds at 4, 7, 10, 13, 16 and 19. Sagittarian Milky Way ( talk) 18:45, 27 June 2024 (UTC) reply

If we forget about the muon's half-life, what would matter made from muonic atoms actually be like, in terms of physical and chemical properties?

(Yes, I know this is about as realistic as all those predictions of the chemical and physical properties of things like oganesson. But since there are published papers about that, maybe someone has considered this?) Double sharp ( talk) 04:00, 27 June 2024 (UTC) reply

In Muonic atoms you can see that adding one muon instead of an electron in an atom makes it like the element with a one lower atomic number. But if all electrons were replaced with muons, then it would behave like a tiny atom. So then you could expect the materials formed to be much denser. 8,000,000 times denser. Also I would expect chemical bonds to be much, much stronger, and may be capable of making the material dense enough to initiate atomic fusion: ( Muon-catalyzed fusion). With much stronger bonds, melting points of covalent network solids would be much higher. However I might expect similar molecular structures, but on a much smaller scale. Graeme Bartlett ( talk) 12:05, 27 June 2024 (UTC) reply

In muonic atoms and molecules it is important to account for the QED corrections properly. They are much bigger than those in electronic atoms and molecules. Ruslik_ Zero 20:30, 27 June 2024 (UTC) reply

Interesting. Muon-catalysed fusion does seem to be the show-stopper for this idea, since that makes it likely that a tank of muonic H₂ (if we magically turn off the decay of the muons) would undergo significant spontaneous fusion. And the same thing would likely hold in general. So, even if the muon magically didn't decay, matter using it to replace all electrons would likely not be that stable either. :(

Thanks for the answers! Double sharp ( talk) 13:11, 1 July 2024 (UTC) reply

June 28 Information

Moved here from the Miscellaneous section of the Reference desk.  -- Lambiam 15:42, 28 June 2024 (UTC) reply

Time as we know it started with the Big Bang and following the Big Bang the universe continues to expand at an accelerating rate. Additionally based on the astrophysical presumption that the expansion of the universe will cease to accelerate and will lead to what astrophysicists are calling “the big crunch” whereby the universe will start to retract back to a point of singularity leading to repeated Big Bang events; my question is that if the universe was started to retract would time started to flow backwards? 149.12.2.131 ( talk) 13:15, 28 June 2024 (UTC) reply

No, even if the Big Crunch were the fate of the universe. Entropy only goes one way. Supernovae won't reassemble themselves. People will not start sdrawkcab gniklat. Clarityfiend ( talk) 13:44, 28 June 2024 (UTC) reply

If the arrow of time reverses, so does the direction of the increase of entropy. There is nothing per se contradictory with a model of the universe with a timelike parameter ${\displaystyle \tau }$ such that its entropy increases monotonically with ${\displaystyle \tau }$ for ${\displaystyle \tau <0}$ and decreases monotonically with ${\displaystyle \tau }$ for ${\displaystyle \tau >0.}$ On one side of ${\displaystyle \tau =0}$ the arrow of time points in the positive direction and on the other side it points in the negstive direction – towards ${\displaystyle \tau =0.}$

The picture is complicated by quantum physics. The von Neumann entropy, which may be a more fundamental measure, should be invariant for a closed system. The universe as a whole is a closed system. The fact that we observe increasing entropy may be due to our inability to access the information that is "somewhere". As Special Agent Mulder would say, "the truth is out there".  -- Lambiam 17:01, 28 June 2024 (UTC) reply

If the universe becomes all or mostly black holes, might they coalesce? ← Baseball Bugs ^{What's up, Doc?} carrots→ 19:22, 28 June 2024 (UTC) reply

No-hair theorem Sagittarian Milky Way ( talk) 22:28, 28 June 2024 (UTC) reply

So, the consensus is that we have to wait and see? DOR (ex-HK) ( talk) 21:25, 28 June 2024 (UTC) reply

There have been and are many theories about the end of the universe. Given our present understanding of cosmology, the observations do not yet allow us to settle on a single one. We may need to keep observing for a couple of trillions of years. I don't think it can be definitely ruled out that the universe is an ergodic system that happens to be in a very low state of entropy. If it is, the Poincaré recurrence theorem promises us an eternal return. ^[6]  -- Lambiam 08:50, 29 June 2024 (UTC) reply

June 29 Information

Hey, I would love to know the courtship behavior of this weird yet incredible creature. Wolverine XI ^{( talk to me)} 08:35, 29 June 2024 (UTC) reply

The article on Narwhal is assessed as a "Good Article", but it is rather weak on their courtship. Abductive ( reasoning) 09:44, 29 June 2024 (UTC) reply

Yeah, I bought this book called "Sex in Cetaceans" from Amazon about a month ago; I'll let you know if I find anything. Wolverine XI ^{( talk to me)} 10:17, 29 June 2024 (UTC) reply

[T]he finer details of what goes on during this mating season are largely unknown due to the difficulties of observing the animals in their natural habitat, which is covered in dense ice that has just a few percent of open water [...and] researchers have yet to identify any noises specific to mating or courtship [...]

• Castro, Joseph (5 June 2017). "Animal Sex: How Narwhals Do It". livescience.com. Future US, Inc.

Although much of what we know about their courtship and mating habits is based on indirect evidence and speculation, perhaps size matters.

See:

• Hunt, Katie (18 March 2020). "We finally know why narwals have tusks (Hint: It has to do with sex)". CNN.
• Graham, Zackary A.; Garde, Eva; Heide-Jørgensen, Mads Peter; Palaoro, Alexandre V. (March 2020). "The longer the better: evidence that narwhal tusks are sexually selected". Biology Letters. p. 20190950. doi: 10.1098/rsbl.2019.0950.

-- 136.54.106.120 ( talk) 18:07, 29 June 2024 (UTC) reply

Then that means the article is comprehensive, since we already mention the tusk stuff under description. Wolverine XI ^{( talk to me)} 21:31, 29 June 2024 (UTC) reply

OK, it's getting close to that time again when I have to clean my dryer duct (which requires me to move my gas-powered dryer away from the wall, disconnect the duct, install a mesh guard and reconnect the duct prior to cleaning the duct from the outside in while running the dryer to blow the lint out (mostly all over my face and clothes until I end up looking like Dick Van Dyke the chimney sweep in the film Mary Poppins), and then perform the same operation in reverse and push the thing back into its normal position after completing the cleaning). Last time I did this, though, it caused a big problem: pulling the dryer out from the wall went without a hitch, and for the most part so did the cleaning (except that I got all dirty like I already said above, and I got blisters and cuts on my hands from forcing the brush in, because the lint was hard-packed in places) -- but when I pushed the dryer back in, the fitting connecting it to the (supposedly flexible) gas hose "popped" in a way I've never seen before (and hope to never see again), completely disconnecting the hose from the dryer, and causing gas to start pouring in full blast from the still-open hose (fortunately I managed to shut off the main gas valve before the gas could reach its lower ignition limit, or this could have been a real disaster!) So, for next time, are there any tips for me how to pull the dryer out and push it back in without risking this happening again? 2601:646:8082:BA0:DC11:A4D3:D067:7B8E ( talk) 23:37, 29 June 2024 (UTC) reply

Have you considered hiring a professional? Sometimes saving money can be expensive. -- 136.54.106.120 ( talk) 00:27, 30 June 2024 (UTC) reply

This is a reference desk, not an instruction guide. In any case you should not take advice on maintaining gas appliances from random people on the internet. Get a professional to do it. Shantavira| ^{feed me} 08:59, 30 June 2024 (UTC) reply

I'd expect a shut-off valve between the fixed pipe coming out of the wall and the supposedly flexible hose connecting it to the the dryer (there was one for the gas hob where I used to live; I now live gas free), but if there's none, there's only the main gas valve. I suggest closing it before moving the dryer, just to be sure. PiusImpavidus ( talk) 09:14, 30 June 2024 (UTC) reply

Yes, there is indeed a shut-off valve for the dryer, which I will consider closing before moving the thing (hopefully it will run in "air fluff" mode even with the gas shut off?) My question, though, was about how to move the appliance in such a way as to avoid the risk of rupturing the gas connection??? 2601:646:8082:BA0:DC11:A4D3:D067:7B8E ( talk) 23:28, 30 June 2024 (UTC) reply

You obtain from the hardware store these little discs called "furniture sliders", some are felt and some are hard plastic, and put them under the feet of the dryer. Have a potato ready to jam in the gas line should it rupture. Abductive ( reasoning) 06:40, 1 July 2024 (UTC) reply

Thanks! Or maybe I'll put a rug under it, and use that to pull it out and back in -- would that help reduce the risk of rupture? And maybe I'll pull out the washing machine as well, to make it easier to reach the valve in case the hose lets go again! 2601:646:8082:BA0:DC11:A4D3:D067:7B8E ( talk) 21:49, 1 July 2024 (UTC) reply

My guess is that the hose was already halfway off after the first part of the procedure (moving the dryer away from the wall); being unaware of the risk of it slipping off you didn't notice it. Was the hose secured to the fitting with a tight hose clamp? This reduces the risk of accidental unintended disconnection.  -- Lambiam 08:50, 1 July 2024 (UTC) reply

No, it was not secured, and it still isn't (the person who installed the new hose didn't bother with a clamp) -- I'll make sure to fix that before attempting to clean the duct! Also, FYI, the old hose was at least 10 years old (and probably at least a couple years older than that -- God knows how long the previous owners lived in my house before I bought it from them, and from all the signs they didn't bother to do any maintenance to any of the appliances, they didn't even bother to flush the water heater, whereas I flush it every fall) -- so I think corrosion might have been a factor too! 2601:646:8082:BA0:DC11:A4D3:D067:7B8E ( talk) 21:49, 1 July 2024 (UTC) reply

Everywhere I've seen in the US, the "gas connector"--the segment of gas-line from the permanent house infrastructure (near appliance shut-off valve) and the appliance itself is flexible metal with flared threaded connectors, or occasionally rigid metal like the house piping itself. I haven't seen anything that would have a hose clamp in decades. There is an older vs newer style of flexible metal tubing, with the newer ones (CSST: "corrugated stainless steel tubing") apparently designed to overcome how easily the older ones broke (older ones do not meet current code if I recall). So first order of business is make sure what you now have is up to code as far as type of connector and material. I'm not a plumber though, so best to check with one, or at least read product literature carefully at your local supply store. DMacks ( talk) 16:07, 2 July 2024 (UTC) reply

Right -- and to clarify, last time it was actually the connector (presumably of the flared threaded type as you describe) which "popped", i.e. separated circumferentially into 2 unequal parts, thereby completely disconnecting the tubing from the appliance -- not the tubing itself! (Which is why I think corrosion probably played a part -- there's no way I can see such a fitting doing this unless the threads were rusted through, and with the thing having spent well over 10 years exposed to high humidity, car exhaust, chemicals, etc., this does sound plausible!) 2601:646:8082:BA0:DC11:A4D3:D067:7B8E ( talk) 23:51, 2 July 2024 (UTC) reply

June 30 Information

I know at least 1 free commercial site lets you find hourly pressure since long enough ago but 30yrs would be manually averaging many thousands of numbers on 10,958 webpages one per day. I just want the regular $0 version not the paid certificated version for lawyers, bridge engineers etc Sagittarian Milky Way ( talk) 15:26, 30 June 2024 (UTC) reply

By "station" do you mean "weather station" and by "pressure" do you mean "atmospheric pressure"? (If so, I don't know the answer, but I was struggling to understand the question, so perhaps others were also.)

Is the mention of bridge engineers pertinent to your reason for asking, or an inadvertent red herring? 151.227.226.178 ( talk) 09:57, 1 July 2024 (UTC) reply

Weather station, atmospheric pressure. On one of the government weather/climate websites I saw a link to certified super-duper extra-checked data intended for lawsuits etc but presumably anyone can pay. Sagittarian Milky Way ( talk) 12:50, 1 July 2024 (UTC) reply

And a specific weather station, not all of them averaged together (the only weather textbook I was lucky enough to have read (an undergraduate weather 101-level covering all meteorology) just called them stations) Sagittarian Milky Way ( talk) 13:00, 1 July 2024 (UTC) reply

1. Some authors write "light has no rest-mass", whereas others write "light has zero rest-mass".

2. There are some arguments against ascribing any rest-mass, even a zero rest-mass, to the light, e.g.

First, The formula of relativistic momentum may collapse once any value, including any zero value, is substituted for the rest-mass in that formula.

Second, light cannot be at rest, hence - logically - it cannot carry any rest-mass. That said, and bearing in mind - that although (for example) the function ${\displaystyle f(x)=1/x}$ has no value at ${\displaystyle x=0}$ this does not mean that the value of the function ${\displaystyle f(x)=1/x}$ at ${\displaystyle x=0}$ is zero - and more generally: when we don't ascribe "any value" to a property we don't mean the value of the property is zero, the same must be true for what we (don't) mean by "light has no rest-mass".

Third, from a logical point of view: Any sentence, whether true or flase, may be substituted for A in the true sentence "If light is at rest then A". Hence, for any value X, we will always get it right saying "If light is at rest then its mass will then be X". Hence for any value X, we will always get it right saying "if light has a rest mass then its value is X". Hence we would collide with a contradiction, if we assumed light carried any rest mass - even a zero one only.

3. On the other hand, there is a well known argument in favor of ascribing a zero rest-mass, to the light: This is actually a direct consequence, of combining the formulas ${\displaystyle E^{2}=m_{0}^{2}c^{4}+p^{2}c^{2}}$, and ${\displaystyle E_{light}=p_{light}c.}$

4. To sum up: Bearing in mind the pros and cons for/against ascribing a zero rest-mass to the light, I wonder if light, has no rest-mass at all, even not a zero rest-mass, or it still has a zero rest-mass.

HOTmag ( talk) 16:37, 30 June 2024 (UTC) reply

To me, this relates more to semantics than physics. "Zero rest-mass" implies a countable quantity, as if it could be measured; "no rest-mass" suggests that rest-mass is not necessarily measurable. My understanding (based on knowledge from c.1980s) is that photons do not have a defined mass in a stationary state; and, "zero" is useful as a construct. -- 136.54.106.120 ( talk) 18:02, 30 June 2024 (UTC) reply

As to your last word: I suspect zero can't be a construct. For more details, see my previous response, in its section 2, against ascribing any rest mass to the light, even a zero rest mass only. HOTmag ( talk) 10:43, 1 July 2024 (UTC) reply

I was thinking of the noun "construct" referring to using "zero" as a logical placeholder for the absence of anything, nonexistence or "nothing" -- rather than a cardinal number. -- 136.54.106.120 ( talk) 17:58, 1 July 2024 (UTC) reply

See my first response. Its section 3 gives an argument for ascribing a zero rest-mass to the light, zero being a cardinal number. On the other hand: section 2 gives three arguments against ascribing any rest mass - including a zero rest-mass - to the light, zero being a cardinal number. That's why I asked my question indicated in section 4. HOTmag ( talk) 18:34, 1 July 2024 (UTC) reply

The concept of "zero" overlaps mathematics and philosophy. One could say that there are varying forms of nonexistence (?) — Preceding unsigned comment added by 136.54.106.120 ( talk) 18:53, 1 July 2024 (UTC) reply

It seems you didn't get my point. I'm focusing on the contradiction between section 2 and section 3, both referring to zero as a cardinal number. The implicit question was: Can anyone remove the contradiction? HOTmag ( talk) 20:32, 1 July 2024 (UTC) reply

Okay, shifting focus from philosophy to physics: quantum electrodynamics and the Standard Model of particle physics treat photons as massless particles, providing theoretical support for zero rest mass. [7] [8] Nevertheless, a photon at rest is a non-entity. -- 136.54.106.120 ( talk) 22:08, 1 July 2024 (UTC) reply

A. Re. your first source: It claims light has a non-zero rest mass.

B. Re. your second source: Why didn't you provide also my section 3 as an additional "theoretical support for zero rest mass?"

C. However, please notice my section 3 contradicts my section 2. Also your second source contradicts my section 2. The implicit question was: Can anyone remove the contradiction?

D. Re. your last sentence. From a logical point of view, saying that "a photon at rest is a non-entity", is the same as saying that "light cannot be at rest". So, not only do I know that a photon at rest is a non-entity, i.e that light cannot be at rest, I also use this fact for establishing my section 2 (in its "Second" and "Third" paragraphs).

HOTmag ( talk) 22:47, 1 July 2024 (UTC) reply

The real numbers are a field, which implies it has both an additive and a multiplicative identity, traditionally denoted by 0 and 1. These elements are true real numbers, not cardinal numbers.

There is a traditional embedding of the finite cardinal numbers in the real numbers which sends the cardinal number 0 to the real number 0 and the cardinal number 1 to the real number 1, but this fact does not turn these real numbers into cardinal numbers.

Since 0 kg = 0 μg = 0 oz = 0 Da, there is no need to specify the unit; "zero mass" is unambiguous.  -- Lambiam 23:43, 1 July 2024 (UTC) reply

As to cardinal numbers: Please notice I hadn't been the first to claim that zero was a "cardinal number". The anonymous user I responded to had, and I only followed them, adopting the term "cardinal number" they had already used, so your response should have responded to them rather than to me.

As to your last sentence: Did anyone claim there was a need to specify the unit? I only claimed there was a contradiction between sections 2,3 in my first post, and I asked if anyone could remove the contradiction. If you think there is anything wrong in my arguments in section 2 against attributing a zero rest-mass to a photon, please specify - both the wrong argument - and what's wrong in it. HOTmag ( talk) 11:37, 2 July 2024 (UTC) reply

( edit conflict)

Re:

A) First source: I only read the abstract and noted This review attempts to assess the status of our current knowledge and understanding of the photon rest mass, with particular emphasis on a discussion of the various experimental methods that have been used to set upper limits on it. [And, yet]: failure to find a finite photon mass in any one experiment or class of experiments is not proof that it is identically zero and, even as the experimental limits move more closely towards the fundamental bounds of measurement uncertainty, new conceptual approaches to the task continue to appear.

B) Your #3 section does indeed support zero rest mass; otherwise, particles with non-zero rest mass cannot travel at the speed of light, as it would require infinite energy. Since photons always travel at the speed of light in vacuum, they must have zero rest mass.

...To be continued? (gotta go now) -- 136.54.106.120 ( talk) 00:03, 2 July 2024 (UTC) reply

It is (I think) conceivable that not all photons travel at exactly the same speed; if the slowest photons move at a fraction of 10⁻⁸⁰ slower than the fastest ones, we would not be able to detect that experimentally. Photons traveling in vacuum are traveling through quantum foam. It is presently unclear if that affects their speed; see Quantum foam § Experimental results  -- Lambiam 10:51, 2 July 2024 (UTC) reply

A) See p. 81 in your first source: In section 2, we introduce the theoretical foundation for massive photons, via a discussion of the Proca equations... Using the Proca equations as a starting point, several possible observable effects associated with a nonzero rest mass of the photon are developed in section 3.

B) You are actually repeating what I'd claimed in section 3. However, my question, was not about section 3 you're repeating, nor about my section 2 whose consequence actually contradicts the opposite consequence of my section 3, but rather about whether this contradiction could be removed. For it to be removed, one should show what's wrong in my argument in section 2 or in section 3. For showing what's wrong in such an argument, one should quote the wrong step in that argument and then explain why this step is logically wrong. HOTmag ( talk) 11:37, 2 July 2024 (UTC) reply

"Rest mass" is just another term for " invariant mass", a property of a physical object that is not dependent on the coordinate system of an observer – in contrast to its relativistic mass, which can be different for different observers. When no confusion is possible, physicists will use just "mass" instead of "invariant mass" and describe the photon as a massless particle. This has the same meaning as saying that photons have zero invariant mass, or equivalently that they have zero rest mass. It is pointless to seek more behind this expression.  -- Lambiam 18:46, 2 July 2024 (UTC) reply

Re. your first sentence: Yes, this is a well known fact.

Re. your second sentence. Those who use the term "massless" don't recognize the relativistic mass. But if you're among those who do, then you should avoid the confusing term "massless", because any particle (e.g. a photon) carrying no rest mass does carry a non-zero relativistic mass.

Re. your last two sentences: I guess you want to claim that the term "a photon's rest mass" doesn't mean "a photon's mass when at rest". But if so, then "a photon's rest mass" must mean "a photon relativistic mass", whereas this kind of mass is non-zero, so how does this interpretation of "rest mass" relate to my question about those authors who claim that a photon carries a zero rest mass? HOTmag ( talk) 20:29, 2 July 2024 (UTC) reply

This thread reminds me of Codd's Null (SQL). A null indicates a lack of a value, which is not the same thing as a zero value. "No rest mass" seems pretty like the null case. Mike Turnbull ( talk) 10:50, 3 July 2024 (UTC) reply

Yes, Just as the function ${\displaystyle f(x)=1/x}$ at ${\displaystyle x=0}$ is a null case.

So, combining the formulas ${\displaystyle E^{2}=M_{0}^{2}C^{4}+P^{2}C^{2}}$, and ${\displaystyle E_{light}=P_{light}C,}$ does not let us conclude that a photon carries a zero rest mass ${\displaystyle M_{0},}$ because the first formula ${\displaystyle E^{2}=M_{0}^{2}C^{4}+P^{2}C^{2}}$ only refers to bodies carrying a rest mass ${\displaystyle M_{0},}$ while a photon - being a null case - doesn't carry any rest mass because it can't be at rest. HOTmag ( talk) 19:07, 3 July 2024 (UTC) reply

Maybe you overlooked the statement that "rest mass" is just another term for "invariant mass". So "a photon's rest mass" means "a photon's invariant mass". Maybe you also overlooked the mentioned restriction to cases when no confusion is possible. But I fear that for some people confusion is always a possibility.  -- Lambiam 18:28, 3 July 2024 (UTC) reply

I didn't overlook the statement that "rest mass" is just another term for "invariant mass". On the contrary, I explicitly pointed out in my last response: Re. your first sentence: Yes, this is a well known fact. So, I already agreed that "rest mass" was just another term for "invariant mass".

I also didn't overlook the mentioned restriction to cases when no confusion was possible. On the contrary, I explicitly pointed out in my last response: Those who use the term "massless" don't recognize the relativistic mass. But if you're among those who do, then you should avoid the confusing term "massless", because any particle (e.g. a photon) carrying no rest mass does carry a non-zero relativistic mass. In other words, those "cases when no confusion is possible" are only those cases when the relativistic mass is not recognized.

To sum up: there are only two kinds of a given body's mass:

A. The body's current relativistic mass. Please notice, the value of this kind of mass is always non-zero, even if the body is a photon.

B. The body's invariant mass, i.e. the body's rest mass, i.e. the relativistic mass the body would have carried if it had been at rest. Please notice, the very existence of this kind of mass depends on whether the body is a massive one or is a photon: If it's a photon, which actually can't have a rest, then it can't have a rest mass either, logically speaking.

My question was about those authors who claimed that a photon carried a zero rest mass, as opposed to B. HOTmag ( talk) 18:56, 3 July 2024 (UTC) reply

July 1 Information

Quickly saying, I asked here because the references are far too complex to understand, and the Wikipedia pages don’t list defining characteristics. 38.23.177.112 ( talk) 03:09, 1 July 2024 (UTC) reply

This paper says, "No morphological apomorphies are known", which I guess means it's just molecular. Abductive ( reasoning) 06:47, 1 July 2024 (UTC) reply

One reason with I hate phylogeny… without distinguishing traits, how can clades be properly defined?

Am I the only person who hates phylogeny for this particular reason? 38.23.177.112 ( talk) 10:22, 1 July 2024 (UTC) reply

I'm sure it bugs many people. But one can only hate phylogeny if one cares about phylogeny. And unless one is publishing scientific articles in the field, hating it will accomplish nothing. Abductive ( reasoning) 21:04, 1 July 2024 (UTC) reply

I suspect that hating phylogeny will accomplish very little also for people publishing scientific articles in the field.  -- Lambiam 18:06, 2 July 2024 (UTC) reply

July 2 Information

Just wondering. I had a black and white TV in my room as a kid in the late 80s, used a black and white TV that came with my flat in the early 2000s and (apparently) the TV license in the UK is still cheaper for black and white even now. Iloveparrots ( talk) 01:56, 2 July 2024 (UTC) reply

It seems highly unlikely. Why would anybody continue to make a product for which there is no demand? And if, for some reason, you wanted to view the screen that way, you could just turn the color off on a regular, color TV. Clarityfiend ( talk) 08:31, 2 July 2024 (UTC) reply

Steady on there with the 'no demand'. According to this, there were "4,200 black and white TV licences in force in March 2022" in the UK, and I imagine some of those people are quite demanding. I was thinking about this recently, that families often didn't own TVs back in the black and white days in the UK, they rented them from DER. Maybe not owning things, appliances etc., will make a comeback one day if the price (no cost) and logistics (arrives instantaneously) work. Still waiting for that communist utopia I was promised as a child... Sean.hoyland ( talk) 09:55, 2 July 2024 (UTC) reply

This 2008 BBC article says that new blank & white televisions can still be found in the UK, but I imagine that they would have been from old stock rather than newly manufactured. A reasonably thorough Google search failed to find any actual new ones. Alansplodge ( talk) 15:26, 2 July 2024 (UTC) reply

Blind people qualify for a 50% discount on their UK TV licence; a B&W licence is a third of the price of a colour one. So by going B&W (which they may not be able to see anyway) they pay about one sixth (£28.50) of the full price (£169.50). -- Verbarson   ^talk _edits 17:32, 2 July 2024 (UTC) reply

It seems amazingly regressive that everyone has to pay hundreds of dollars or £169.99 a year to own a TV (more than throwing a basic TV in the Thames every year and almost as much as basic cable just for BBC). In the states they offered everyone a subsidy just to avoid the much cheaper one-time cost of the box to run analog TVs on digital signals. Sagittarian Milky Way ( talk) 23:21, 3 July 2024 (UTC) reply

In the words of Frank Zappa, "Communism doesn't work, because people like to own stuff." Regarding old TV's in stock, I recall not too many decades ago reading that there were still after-market parts available for the Model A Ford, which hadn't been manufactured since the 1930s. ← Baseball Bugs ^{What's up, Doc?} carrots→ 15:38, 2 July 2024 (UTC) reply

I expanded the concept slightly, and found a bunch of suppliers of new monochrome monitors built with modern technology and wiring (LCD with DVI, etc.). Get a tuner for your favorite local broadcast mode and you're all set. Lots of medical and other imaging is intrinsically monochrome, so there's a market for monitors optimized for high resolution and other visual qualities rather than colors and their rendering properties. DMacks ( talk) 16:19, 2 July 2024 (UTC) reply

July 4 Information

Mathematics Information

June 20 Information

I wanted to ask you for help in better understanding two concepts that leave me a little perplexed regarding the first fundamental form:

1) The first fundamental form was defined to me as follows: given a parameterization ϕ(u,v) , the metric A is found with the dot products like ϕu​⋅ϕv​ (through the 4 permutations of u,v), where the dot products are restricted to the tangent spaces induced by R3. It was then explained that quantities dependent on E,F,G (such as the Christoffel symbols, and therefore the curvature via Gauss's Theorema Egregium since it shows that they depend only on the Christoffel symbols) are intrinsic quantities, meaning they do not depend on how the surface is immersed in R3, but are intrinsic to the object itself.

My confusion revolves around this: if I define the first fundamental form in this way, I note that ϕ(u,v) is the map ϕ:U→R3, so what comes out of this map is precisely the figure I have as a surface in R3R3, that is, the shape it takes. In fact, the map gives me the coordinates (x,y,z). Now, ϕ​ and ϕv​ are the tangent vectors to that figure, so they indeed depend on the shape realized in R3. Then I define the matrix A through the dot products of ϕu​ and ϕv​, so what is intrinsic here? I am using tangent vectors to a figure that has a shape given by ϕ:U→R3, so I would say it indeed depends on the immersion and how the figure is geometrically realized in it.

What seems to be suggested by the explanation is this: if I immerse the "abstract concept" of a sphere in R3, I have different realizable figures. I do not understand this concept given the considerations above: curvature depends only on E,F,G through the Christoffel symbols, but E,F,G depend on the dot products of tangent vectors to a shape of the surface, so on an immersion of it in R3.

2) The second question is this: if I change parameterization, I will have new ϕi'​,i∈u,v which differ from the initial ones, so I will find E',F',G'. However, for an object (let's take the usual sphere), the curvature is fixed and depends only on E,F,G right? Well, if I have changed parameterization and have E',F',G', why wouldn't the curvature change? They are different values. It seems to me that by changing parameterization, the first fundamental form changes and therefore the curvature should change as well (but it shouldn't obviously be so).

Could you help me with these two questions? Thank you. -- 151.36.108.141 ( talk) 15:42, 20 June 2024 (UTC) reply

E,F,G are relative to a particular tangent space and the values will of course change if one changes the tangent space. One has to get rid of the tangent space dependency to get things like the curvature. The determinant gives a measure of the area of dudv and dividing the determinant of the second fundamental form by that of the first fundamental form gives something independent of dudv - and which in fact is the Gaussian curvature. NadVolum ( talk) 15:09, 21 June 2024 (UTC) reply

June 22 Information

I noticed that 1/7 in base that 3,6 & 9 are missing from the expansion in base 10, but it appears that there is a pattern.

• k = 2, 1/3 in base 5 is .13(rep), 2/3 in base 5 is .31 (no digit which is a multiple of 2 appears in the pentary expansion, neither 2 or 4 occur
• k = 3, 1/7 in base 10 is .142857(rep) (no digit which is a multiple of 3 occurs in the decimal expansion, none of 3, 6 or 9 occur
• k = 4, 1/13 (1/C) in base 17 is .153FBD(rep) (not only doesn't any digit which is a multiple of 4 occur (4,8,C,G), it appears that digits which are a multiple of 2 occur.
• k = 5, 1/26 (1/L) in base 26 is .164OJL(rep) (no digit which is a multiple of 5 occurs (5,A,F,K,P)

Any idea for a proof or extension of this? (I can't find an easy calculation in base 37) Naraht ( talk) 02:11, 22 June 2024 (UTC) . reply

There seems to be a typo in the k = 5 case; (k-1)k+1=21, not 26, and 1/26 base 26 is just .1. It might be easier to use a different notation for large bases, say by inserting a comma between each digit and leaving the digits in base 10. So 1/21 = .1,6,4,24,19,21(rep). In this notation 1/31 = (base 37) .1,7,5,35,29,31. I think you can probably see what's going on by looking at k=10 and k=100: 1/91 = (base 101) .1,11,9,99,89,91(rep), and 1/9901 = (base 10001) .1,101,99,9999,9899,9901(rep). The pattern is 1/(k²-k+1) = (base k²+1) .1,k+1,k-1,k²-1,k²-k-1,k²-k+1, which shouldn't be too hard to verify. There is almost certainly python code to compute fractions in large bases to do further experimentation. k²-k+1 and k²+1 are both cyclotomic polynomials, and there are probably similar patterns when you look at 1/Phi_m(k) base Phi_n(k) for various m and n. -- RDBury ( talk) 15:15, 22 June 2024 (UTC) reply

PS. The fact that the denominator is a cyclotomic polynomial is the part of what makes this work, the other part isn't that the base is a cyclotomic polynomial in k, but that it's equal to ±k mod the denominator. In this case the denominator is Φ₆(k) and the denominator is Φ₆(k)+k. A generalization is that if P(x) is congruent to x mod Φ_n(x) (taken as polynomials in x) then for a 1/Φ_n(k) has period dividing n base P(k). For example Φ₁₀(x)=x⁴-x³+x²-x+1 and P(x)=x⁸+x⁴+x²+1 is congruent to x mod Φ₁₀(x). So the generalization states that Φ₁₀(k) has period dividing 10 base P(k). For k=10 we get 1/9091 = (base 100010101) .11001,110010,1100100,11001001,9999909,99999099,99900090,98910000,89009099,90010191(rep) and this indeed has period 10. If P(x) is congruent to -x mod Φ_n(x) the rule is that the period divides 2n. For n=3, k=3, 1/13 = .076923(rep) base 10; for k=4, 1/21 = .0,13,12,16,3,4(rep) base 17; for k=10, 1/111=.0,91,90,100,9,10; and in general 1/(k²+k+1) = .0,k²-k+1,k²-k,k²,k-1,k(rep). There are probably additional tweaks and generalizations you can make on this. -- RDBury ( talk) 16:03, 23 June 2024 (UTC) reply

thank you for all of this, my noticing of the missing "k" was a small part of what could actually be found. Naraht ( talk) 16:48, 25 June 2024 (UTC) reply

June 25 Information

If you are defining g(x), why is it written

${\displaystyle \lim _{x\to \pi }{\sqrt {x^{3}f(x)}}=g(x)\,}$,

and not

${\displaystyle g(x)=\lim _{x\to \pi }{\sqrt {x^{3}f(x)}}\,}$,

or are both ways acceptable?

I mean you usually don't say ${\displaystyle {\sqrt {x^{3}f(x)}}=g(x)\,}$, you say ${\displaystyle g(x)={\sqrt {x^{3}f(x)}}\,}$, right? (Yes, g(x) is purely nonsensical in meaning, for demonstrative purposes only :)

173.14.155.129 ( talk) 23:20, 25 June 2024 (UTC) reply

It is definitely more conventional to place the entity being defined in the lhs of the equation, but as long as it is clear which is the definiendum and which the definiens, there is nothing logically wrong with the swapped version – it is merely highly unusual and therefore may put the reader on the wrong foot. This is independent of whether the definiens involves a limit. By the way, the value of the expression ${\displaystyle \lim _{x\to \pi }{\sqrt {x^{3}f(x)}},}$ if defined, does not depend on ${\displaystyle x.}$ If function ${\displaystyle f}$ is continuous at ${\displaystyle \pi ,}$ it is equal to ${\displaystyle {\sqrt {\pi ^{3}f(\pi )}}.}$

 

When asked to determine

${\displaystyle \lim _{~\epsilon \to 0^{+}}(1+\epsilon x)^{\frac {1}{\epsilon }},}$

I'd present the answer in the form

${\displaystyle \lim _{~\epsilon \to 0^{+}}(1+\epsilon x)^{\frac {1}{\epsilon }}=e^{x},}$

but when asked to define the exponential function, I might give

${\displaystyle \exp x=\lim _{n\to \infty }\left(1+{\frac {x}{n}}\right)^{n}}$

as one of several definitions, and then I'd present it in this order.  -- Lambiam 00:02, 26 June 2024 (UTC) reply

Like I said, that was just a bogus example (I'm actually thinking of a segmemt that changes as it grows, so that the midpoint value of the whole is different than the midpoint value calculated "locally", with an infinitesimal length), but you answered the question.

173.14.155.129 ( talk) 01:03, 26 June 2024 (UTC) reply

Quick side note that equality in the sense of definition - as opposed to equality in the sense of identity - is often denoted with a colons-equal := (as a single character, ≔), in which case I believe the function ${\displaystyle g(x)}$ being defined would have to go on the left. GalacticShoe ( talk) 05:41, 26 June 2024 (UTC) reply

What is nonsensical here is (IMHO) using a limit as ${\displaystyle x\to \pi }$ to define ${\displaystyle g(x)}$. I mean, assuming the limit of an expression with a variable ${\displaystyle x}$ used in the actual problem exists, that limit no longer depends on ${\displaystyle x}$. As such the expression defines ${\displaystyle g(x)}$ as a constant function... Could you, please, quote the relevant part of the actual problem you're solving? -- CiaPan ( talk) 12:45, 26 June 2024 (UTC) reply

This was already noted above, but, as the poster themself wrote, the definition was "purely nonsensical in meaning, for demonstrative purposes only". The problem for which they were seeking a solution was, why, when the definiens involves a limit, does the definiendum become the rhs of the defining equation? The answer is that it actually dpes not change position but stays as the lhs.  -- Lambiam 15:04, 26 June 2024 (UTC) reply

Then something like 'defining Y with X by X=Y' would be more clear, not obscuring the core problem with a meaningless babbling... -- CiaPan ( talk) 13:04, 27 June 2024 (UTC) reply

Tha's why I wrote, "as long as it is clear which is the definiendum and which the definiens, there is nothing logically wrong with the swapped version". Apparently – or so I guess – the poster saw an equation of the form ${\displaystyle \lim _{z\to x}f(z)=g(x)}$ and incorrectly assumed the intention of this equation was to define ${\displaystyle g.}$  -- Lambiam 16:28, 27 June 2024 (UTC) reply

I would agree it is okay to express the limit on the right side, so that (using a more classical example),

${\displaystyle f'(x)={\frac {df(x)}{dx}}=\lim _{h\to 0}{\frac {f(x+h)-f(x)}{h}}}$

I suppose you could even say ${\displaystyle d=\lim _{h\to 0}h}$, or better still ${\displaystyle d=\lim _{\Delta \to 0}\Delta }$ (?)

On a related notation question (where C is a constant),

if h(x) = h(C,x) = f(C)g(x) does

${\displaystyle h'(x)=h'(C,x)={\frac {dh(x)}{dx}}={\frac {\partial h(C,x)}{\partial x}}=\lim _{D\to 0}{\frac {h(C,x+D)-h(C,x)}{D}}=??{\frac {dh(C,x)}{dx}}}$?

Since C is a constant, doesn't

${\displaystyle \int _{a}^{b}h'(x)dx=\int _{a}^{b}h'(C,x)\partial x=\int _{a}^{b}h'(C,x)dx}$?

If not, what does

${\displaystyle \int _{a}^{b}h'(C,x)dx}$ equal?    2601:188:CB81:CBC0:55BF:ADB0:FA15:C41D ( talk) 23:48, 29 June 2024 (UTC) reply

Mathematical notation is not always as unambiguous as it is sometimes believed to be, but one should draw the limit somewhere. The conventional meaning of ${\displaystyle \lim _{h\to 0}h}$ is that ${\displaystyle \lim _{h\to 0}h=0,}$ so in your shorthand notation you appear to be defining ${\displaystyle d=0.}$  -- Lambiam 07:46, 30 June 2024 (UTC) reply

As to the second question, the issue is made more complicated than necessary by overloading the function name ${\displaystyle h.}$ Let it stand solely for a function of two variables. Then, given a constant ${\displaystyle C,}$ we can define ${\displaystyle k(x)=h(C,x).}$ Taking the derivative with respect to ${\displaystyle x,}$ we can simply write,

${\displaystyle k'(x)={\frac {d}{dx}}h(C,x).}$

There is no need in this case to use the notation for partial derivatives. The notation ${\displaystyle h'(C,x)}$ has no clear meaning and should not be used, so the final question is moot.  -- Lambiam 12:38, 30 June 2024 (UTC) reply

July 2 Information

Given a 2-dimensional array of random values (think of a noisy image) how do you construct an autocorrelation filter that will converge on a given point in the array starting anywhere in the array (or almost anywhere) Philvoids ( talk) 15:41, 2 July 2024 (UTC) reply

Does this answer your question?

1. Compute the two-dimensional discrete Fourier transform of the image (for which you can use the two-dimensional version of the fast Fourier transform algorithm).
2. Filter out the high spatial frequencies.
3. Compute the inverse transform.

 -- Lambiam 17:54, 2 July 2024 (UTC) reply

Below is an 8x8 array of numbers. Start from any one of 64 locations ranging from (x0,y0) = (0,0) bottom left to (7,7) top right. Can you show a formula whose input (x0,y0) always yields as output (X,Y) = (3,3) ?

Y
^
|
|

7  247   51  132   34  223    6  121  243

6   81  196  176  224   77  159  211  171

5  119  245   56  244  141  247   33  115

4  254   49  175  170   95   19  208  108

3  118  204  145  117   25  242  162  229

2   35  200  250  115   45   62  229  135

1  212  219  232  186  196   59   68   74

0  192  207   14  129  102   13   28   65

    0    1    2    3    4    5    6    7    -->X 

Philvoids ( talk) 09:08, 3 July 2024 (UTC) reply

I have a hard time understanding the question. What does it mean for a formula (or an algorithm) to "start from a location"? The constant function ${\displaystyle (x_{0},y_{0})\mapsto (3,3)}$ trivially meets the requirement, but this cannot be what you are looking for. If the output should be the same, regardless of ${\displaystyle (x_{0},y_{0}),}$ why is this location supplied as input? I assume that the matrix of values is also part of the input. What is it about these values that makes ${\displaystyle (3,3)}$ the desired output?  -- Lambiam 12:03, 3 July 2024 (UTC) reply

I have a hard time understanding it as well. I don't know what an "autocorrelation filter" is either, but maybe that's just me. I know what autocorrelation is, and I know what a filter is, but the two words together don't seem to have any special meaning and a Google search wasn't very enlightening. A filter would, according to my understanding of the meaning in this context, produce an array from a another array. The generic application of a filter would produce a sequence from another sequence. For example a noise filter would take, for example, an audio file, and remove the noise producing another file with just the speech or music or whatever. You can use the same idea with two dimensional arrays to clean up images, or three dimensional arrays to clean up video. (This is basically what Lambiam's original answer would do.) Such arrays are typically highly autocorrolated and the outputs of a noise filter would be more so, but I don't see how that translates to "autocorrelation filter". In any case, the question seems to want not an array as output, but a location within the array. In general you have to be more specific about what the function is supposed to do, not just give an example. If I ask for a function with f(2)=4, it could be f(x)=x² or x+2 or just 4; there's not enough information in the question to get a meaningful answer. -- RDBury ( talk) 16:06, 3 July 2024 (UTC) reply

"Given a 2-dimensional array" - it could be any array and in the test example I give an 8x8 array of integers. That is a given data.(It could be a different array, maybe larger.) "Start anywhere in the array" - there are 64 locations in the example array and you can start at (0,0) or (0,1) or (0,2) or...all the way up to (7,7). Whatever formula or procedure or algorithm you provide MUST ALWAYS yield as output the arbitrary (means I chose it) location x=3, y=3 i.e. (3,3) that happens to hold the value 117 in the example. I don't know whether you can manage it, and you may have difficulty with the corner or edge locations. But if you can't solve the question, maybe you can reword it for everyone better than I have managed. Philvoids ( talk) 20:27, 3 July 2024 (UTC) reply

Define function ${\displaystyle f:\mathbb {Z} ^{2}\to \mathbb {Z} ^{2}}$ by

${\displaystyle f(i,j)=(3,3).}$

If that does not solve your problem, can you explain how this falls short?  -- Lambiam 21:26, 3 July 2024 (UTC) reply

@Lambiam Your first response described how you would use an FFT and its inverse to remove high frequency "noise" from the array data. Your latest response abandons the reader to define a map conversion. Philvoids ( talk) 14:55, 4 July 2024 (UTC) reply

I do not understand what problem you are trying to solve. Given how you restated it, my latest response should – using my best effort in interpreting the restatement – be a solution (in fact, the only solution). Since I also understand that it can't be this simple, your pointing out in some detail in which respects it does not satisfy the requirements for being a solution might, perhaps, help me get some grip on what problem you are trying to solve. At the moment, I am totally clueless.  -- Lambiam 17:31, 4 July 2024 (UTC) reply

July 4 Information

Humanities Information

June 23 Information

The grave of Pelham Humfrey states: "Here lieth interred the body of Mr. Pelham Humphrey, who died the fourteenth of July, Anno Dom. 1674, and in the twenty-seventh year of his age". Does this mean age 27, as stated in the article, or rather age 26? Can we be sure about the right interpretation of 17th century English? -- KnightMove ( talk) 16:46, 23 June 2024 (UTC) reply

For what it's worth, our article at Mary Jones and her Bible seems to document a case, in 1800, where " in the 16th year of my age" must have meant "in the year leading up to my 16th birthday", i.e. at the age of 15. I don't know how consistent historical usage would have been about this either way. Fut.Perf. ☼ 18:20, 23 June 2024 (UTC) reply

Ok thanks - and there are sufficient sources to confirm this viewpoint. Example. -- KnightMove ( talk) 18:23, 23 June 2024 (UTC) reply

It's a translation of the Latin phrase "(Anno) Aetatis Suae", and may not have ever been very natural in English... AnonMoos ( talk) 22:42, 23 June 2024 (UTC) reply

Apparently, since we only know the year of his birth, it's not possible to say whether he was 26 or 27 when he died. This is a clever way of putting it. Clarityfiend ( talk) 02:04, 24 June 2024 (UTC) reply

[slinks into dunce corner and hangs head in shame] Clarityfiend ( talk) 06:39, 27 June 2024 (UTC) reply

Thanks, but I don't think so anymore because the phrase is also used for people with completely known birth-and-death dates. Another example to the one I have linked above (Benjamin Franklin), from the same period as Humfrey: "... Mr. Philip Henry, minister of the gospel near Whitchurch in Shropshire, - Who died June 24, 1696, in the sixty fifth year of his age..." ( source) - Henry was 64 years old.

Although we don't know Pelham Humfrey's date of birth anymore, and it probably wasn't known at the time, they seem to have assumed he was 26 years old when he died, and this is the best information we have. That's why several sources give the time of his birth as 1647/48 (never 1646/47), consistently interpreting his gravestone in this way. -- KnightMove ( talk) 05:43, 24 June 2024 (UTC) reply

In Latin it would imply 26.  -- Lambiam 07:17, 24 June 2024 (UTC) reply

It's obviously 26. In your first year, you're age 0; in your second year you're age 1; in your 27th year you're age 26. Nyttend ( talk) 09:53, 24 June 2024 (UTC) reply

Yep. Standard fencepost error. Same thing that confuses some people about the century divides. -- User:Khajidha ( talk) ( contributions) 13:15, 24 June 2024 (UTC) reply

Agreed. When you are in your first year of your age, you have not yet reached your first birthday. Alansplodge ( talk) 14:44, 24 June 2024 (UTC) reply

I strongly suggest that we handle human age the same way as we count floors on buildings. In the USA we start at one and anywhere else we start at zero. This would simplify any emergent confusion. For selected celebrities from Muslimic areas we should also use the lunar calendar to avoid any accusations of cultural appropriation. In the case of scientists engaged in cosmology or astronomy the inverse square rule is mandatory, modified by the curvature of space-time. -- Cookatoo.ergo.ZooM ( talk) 16:18, 25 June 2024 (UTC) reply

Better still, we should handle days, months and years the same way we do hours, minutes and seconds. Today is 2023:05:25. — Kpalion ^(talk) 09:38, 26 June 2024 (UTC) reply

(closing small tag) AlmostReadytoFly ( talk) 11:04, 26 June 2024 (UTC) reply

According to traditional East Asian age reckoning, you were 1 year old when you were born, and this number was added to by 1 on each subsequent Chinese New Year (no relevance to Mr. Pelham Humphrey, of course)... AnonMoos ( talk) 18:29, 26 June 2024 (UTC) reply

June 25 Information

I am curious: why is the Upper Peninsula a part of the state of Michigan, and not a part of the state of Wisconsin? Thanks. 32.209.69.24 ( talk) 04:05, 25 June 2024 (UTC) reply

According to the Michigan article, when it became a state it was granted the U.P. in trade for the settlement of a boundary dispute with Ohio, as Ohio had won that dispute. ← Baseball Bugs ^{What's up, Doc?} carrots→ 05:40, 25 June 2024 (UTC) reply

Wisconsin wasn't granted statehood until over a decade later. At that point it would require a literal act of Congress and consent of both Wisconsin and Michigan to transfer the Upper Peninsula to Wisconsin. -- User:Khajidha ( talk) ( contributions) 14:39, 25 June 2024 (UTC) reply

See Toledo War for the boundary dispute. Nyttend ( talk) 08:21, 26 June 2024 (UTC) reply

Are parties allowed to raise new issues during WTO Compliance Proceedings? Grotesquetruth ( talk) 12:17, 25 June 2024 (UTC) reply

Can you be more specific? DOR (ex-HK) ( talk) 22:08, 25 June 2024 (UTC) reply

According to our article François Duvalier "On 8 February 1986, when the Duvalier regime fell, a crowd attacked Duvalier's mausoleum, throwing boulders at it, chipping off pieces from it, and breaking open the crypt. Duvalier's coffin was not inside, however. A prevailing rumor in the capital, according to The New York Times, was that his son had removed his remains upon fleeing to the United States in an Air Force transport plane the day before." Has his body ever turned up? Thank you, DuncanHill ( talk) 23:54, 25 June 2024 (UTC) reply

It's in storage next to the Ark of the Covenant Chuntuk ( talk) 20:10, 27 June 2024 (UTC) reply

June 26 Information

I once read an Indian story that went like this: "A courtesan was in love with a sadhu who wasn't interested and refused to even go visit her. Sometimes later she provoked the king's anger so he ordered that her ears, nose, hands and feet be cut off and that she be abandoned at a cremation ground. Only at that point did the sadhu go visit her to teach her about the doctrine etc." I think the story is Buddhist but I'm not sure. Does anyone know anything about such a story, specifically the name of the courtsan, and the source? 178.51.74.75 ( talk) 18:32, 26 June 2024 (UTC) reply

(As a Buddhist) I have never come across this. It doesn't sound Buddhist, and sadhus are Hindu. Shantavira| ^{feed me} 08:09, 27 June 2024 (UTC) reply

As Shantavira says, it doesn't sound Buddhist, however, IIRC, many stories do change over time based on time, place, and culture, and I'm pretty sure the Buddha has been referred to as "sadhu" before. While I don't recognize this particular story, there are quite a few Buddhist folk tales that involve imagery related to the "cutting off" of appendages (I put "cutting off" in quotes for a reason, there's a lot of metaphors involved and often these stories are not intended to be taken literally). Three stories come to mind right away because they are so popular: the story of Angulimala ("The Finger Necklace"); the story of Gutei ("Gutei's finger"); and the story of Huike ("Huike Offering His Arm to Bodhidharma"). There are likely many more of these stories, as the Buddhist literature and canon is too large for any one person to know it all. In fact, I've read elsewhere that it is so large, that it is unlikely that 99% of Buddhists are familiar with it as a whole. What's amazing about that, is that the extant literature probably represents less than 20%, given how much has been lost to time and conquerors. The enormity of that idea is frankly astonishing. Christians don't like to hear it, but there are too many coincidences between this imagery and that of Matthew 5:30 and the Sermon on the Mount to dismiss some kind of chain of inheritance of cultural ideas over a period of many centuries. Viriditas ( talk) 23:09, 1 July 2024 (UTC) reply

Note: the Nichiren Buddhists say "Sādhu also means upright, good, honorable, righteous, or correct, and also indicates a holy man or a sage. [9] There's an interesting post on Stack Exchange that talks about the history of the word "sadhu" in Buddhism. In Sri Lanka it is often used to refer to a Buddhist monk. According to one person, "Budu Sadhu" is the term for "Lord Buddha" in Sri Lanka. Viriditas ( talk) 23:20, 1 July 2024 (UTC) reply

Update: I believe I have identified the story, but the details are vastly different. What you describe sounds remarkably like the "Story of Sirimā the Courtesan". [10] You will note the similarity of the courtesan being brought to the cremation ground and the role of the King. The difference is that the courtesan's body is not amputated, but rather decomposed, which plays the same role as amputation in the story, particularly as the body falls apart over time. Another difference is that the doctrine was not necessarily taught to the courtesan in the same way (although she was a follower of the Buddha in the story), but rather was taught to the monk, who went "crazy" obsessing over the courtesan out of his desire for her overwhelming beauty. Her death showed that her beauty was fleeting, which is illustrated in the story as her dead body is being eaten by worms and undergoing putrefaction. I believe it's the same story because the lesson is identical. You initially said the courtesan was in love with the sadhu, but I think you got it backwards. In this story, the sadhu is in love with the courtesan, which in fact, makes a lot more sense. Viriditas ( talk) 23:44, 1 July 2024 (UTC) reply

I can believe that the story I'm faintly remembering had points of similarities with other stories and that maybe there's a constellation of common themes that generate similar stories in Buddhist lore but not that I've misremembered what I read to such an extent that the story of Sirimā that you're recounting has somehow reassembled itself in my head to produce what I remember. But there are definitely common themes. Incidentally my use of the word sādhu is not meant to be taken technically. I'm not certain that's the terminology used in the source I've taken that story from and I obviously can't check: if I knew where I've read that story I'd have no reason to ask the question here. But thanks for the research. 178.51.74.75 ( talk) 00:16, 2 July 2024 (UTC) reply

Perhaps, but there are many other similarities I didn’t mention. In your version of the story, the courtesan provoked the anger of the king; in the story of Sirima, she provokes the anger of the Buddha. Viriditas ( talk) 00:35, 2 July 2024 (UTC) reply

Update: here’s a more condensed version:

Sirima. A courtesan of Rajagaha and younger sister of Jivaka. She was once employed by Uttara (Nandamata) to take her place with her husband (Sumana) while Uttara herself went away in order to indulge in acts of piety. During this time Sirima tried to injure Uttara, on account of a misunderstanding, but on realizing her error, she begged forgiveness both of Uttara, and, at the latters suggestion, of the Buddha. (The details of this incident are given Uttara Nandamata.) At the conclusion of a sermon preached by the Buddha in Uttaras house, Sirima became a sotapanna. [11]

That helps a bit. Viriditas ( talk) 01:16, 2 July 2024 (UTC) reply

My father was just telling me that he recalls a Sunday in the period 1963-1967, when there were three train crashes in the UK, on one day.

When was it and where were they? Andy Mabbett (Pigsonthewing); Talk to Andy; Andy's edits 20:38, 26 June 2024 (UTC) reply

I can't see anything at either List of rail accidents in the United Kingdom or List of accidents on British Rail. The latter does shew two crashes on 1 August 1963, but as well as being, like Mr Spiggott's legs, one too few, it was a Thursday not a Sunday. DuncanHill ( talk) 20:59, 26 June 2024 (UTC) reply

Well, one of those two crashes involved two trains while the other incident only involved one, so on 1 August 1963 you could say that three trains crashed. It's possible (if unlikely) that this is how it got framed on some headlines to sound more sensational. Matt Deres ( talk) 14:20, 29 June 2024 (UTC) reply

June 27 Information

Why did the art of east Asia never have a "renaissance" and moved to a high degree of realism like European art did? I would think isolationism and a conformist culture would be an explanation, but during the Edo period of Japan, they did have some foreign influences still, like fabric patterns were adopted by the Japanese that were Indian and European in origin and brought to the country by the Dutch. It seems odd the influence would stop short of painting and drawing though. -- THORNFIELD HALL ^{( Talk)} 04:32, 27 June 2024 (UTC) reply

You may be interested in our article on Japonisme. -- asilvering ( talk) 05:53, 27 June 2024 (UTC) reply

See also the Hockney-Falco thesis, which holds that the realism in Western Rennaissance art was due to the development of optical instruments. The jury has yet to reach a verdict on that one. Alansplodge ( talk) 11:28, 27 June 2024 (UTC) reply

Anyway, one particular focus of Chinese painting was broad panoramic landscapes, often much wider than they were high, and it's doubtful whether an imposed mathematical perspective of viewing the whole scene from strictly one single geometric point would have been artistically beneficial in that case. As William H. McNeill said, "Chinese painters had learned also to indicate space as a unified and unifying whole, but not by means of linear perspective... Chinese landscapes were projected instead from a shifting aerial point of vision" -- AnonMoos ( talk) 12:58, 27 June 2024 (UTC) reply

P.S. I can't remember the artist or title, but there's a probably European Renaissance painting of human figures against a background of lines of classical pillars (colonnades) receding into the distance, and while use of perspective did add a certain kind of realism to the scene, it also seemed to flashily call attention to itself, so that viewers were more preoccupied with the geometry than with what the painting was actually supposed to be about (or at least I was). Perspective is a powerful technique in the service of art, but it doesn't follow that an artwork with perspective is automatically better than a comparable one without... AnonMoos ( talk) 13:09, 27 June 2024 (UTC) reply

You may refer to Raphael's School of Athens. Cookatoo.ergo.ZooM ( talk) 15:00, 27 June 2024 (UTC) reply

Thanks, but that's not flashy enough. The one I had in mind had a line of Parthenon-like columns starting in the left foreground and receding toward the center distance, and another line starting in the right foreground and also receding toward the center distance. AnonMoos ( talk) 18:51, 28 June 2024 (UTC) reply

Keep in mind that it was a renaissance of something (perceived) to have happened before. Renaissance artists took things further, but they were deliberately grounding themselves in what have become known as "the classics" (i.e. ancient Greece and Rome). The Greeks did not use linear perspective in the way that Brunelleschi and others did, but they did know enough about it to use it for effect and they were generally proponents of the concept of "balance". East Asian art has its own concepts of balance and its own classics that it has to push against and be measured against. Matt Deres ( talk) 15:22, 27 June 2024 (UTC) reply

Possibly, while Japanese artists would have been technically able to realize "a high degree of realism", this was not considered artistically valuable and therefore not worth aiming at. Consider that the high degree of realism of the wax figures at Madame Tussauds is also not artistically appreciated; the art world prefers unrealistically white marble or dark bronze.  -- Lambiam 16:20, 27 June 2024 (UTC) reply

• Chinese painters could do realism, and had their own perspective system that suited long scrolls - Along the River During the Qingming Festival is a famous, much-copied version. They were also very interested in reviving "classic" styles, but this most often meant the older versions of the scholar-artist or "literati" tradition, supposedly practiced by amateur scholars, where realism was mostly associated with "court painting" by professional but not very highly-educated artists (often hereditary). This also affected Japanese painting. Johnbod ( talk) 22:21, 28 June 2024 (UTC) reply

There is something I'm missing in regards to National Rally–The Republicans alliance crisis. What I do understand: Éric Ciotti, the president of The Republicans (LR), attempted to establish an electoral alliance with National Rally for the 2024 French legislative election. Most of the leadership of LR objected to this and voted to remove Ciotti from the presidency of the party and also from membership in the party. Ciotti sued and got a court ruling that he was still the president of LR.

However, the article does not clearly explain why the court found in favor of Ciotti, probably due to translation problems. It says: "The two successive exclusions of Ciotti, by the political bureau on 12 June then by the same body and the national council on 14 June, are considered to have no legal value by the main party concerned. Both were subsequently challenged in court in summary proceedings and suspended by the courts, which ruled on the fact that the lower court must be seized “within eight days” by “the most diligent party”, failing which “the suspension measure ordered will lapse”." What does this mean with the lower court being "seized" by "the most diligent party"? Is this supposed to mean that in eight days (after when?), LR would be allowed to remove Ciotti again? -- Metropolitan90 (talk) 05:27, 27 June 2024 (UTC) reply

The court decision is only a temporary one which allows Ciotti to continue as president of Les Républicains until the underlying issues are decided upon. The issue is whether the party members who voted to exclude him did so in conformity with party rules (normally it would be the party president who calls for an extraordinary bureau meeting such as the one that voted to exclude Ciotti, but obviously, that is not what happened). The anti-Ciotti faction's argument is that an alternative way of calling such a meeting is if a quarter of the members of the national executive request it, which is how they proceeded before voting Ciotti's exclusion. [12] Ciotti may have won the initial judicial battle, but he is clearly in a minority position within his party, and most members have refused to follow him in an alliance with the Rassemblement National. Xuxl ( talk) 15:28, 27 June 2024 (UTC) reply

June 28 Information

I am proofing a presentation that makes reference to Talos. It doesn't give any form of time period. This is for a general audience, not historians. What time period should be used? I don't like any ideas I've had such as: "Around 300 BC..." is boring. "In the third century BC..." is confusing. "In Hellenistic Greece..." only makes sense if you have heard of "Hellenistic" before. 75.136.148.8 ( talk) 11:15, 28 June 2024 (UTC) reply

What is this "Talos period" you speak of? AFAIK, there is no period associated with the mythological Talos you've linked to. Clarityfiend ( talk) 11:20, 28 June 2024 (UTC) reply

You can say, "In 2024, I prepared a presentation that makes reference to Talos." If you want us to tie spme statement to a time period, you need to indicate what the statement is. The earliest known references to the myth, by Simonides of Ceos, date from the Lyric Age of Greece – which unfortunately will only make sense to people who have heard of "the Lyric Age of Greece" before. But I guess this is true for all terms, from Bronze Age to Hellenistic Greece to Anthropocene.  -- Lambiam 19:32, 28 June 2024 (UTC) reply

Just as a reference, I asked on Reddit as well. The answer on Reddit was simple: "Use Circa 300BCE because most people will understand that." You can see the answers here are baseically "We are going to be as pedantic as possible and refuse to provide any answer that might be considered useful." 75.136.148.8 ( talk) 20:09, 28 June 2024 (UTC) reply

No, I would have answered the 300BCE stuff as well but just did not consider that was a good idea. Some will like their coffee sweet and other won't, and we're taking care of your welfare too. You will not shine the same in your presentation depending on the pot you're taking your sugar from. -- Askedonty ( talk) 21:24, 28 June 2024 (UTC) reply

Copping an attitude is not likely to improve your chances of getting what you're after. ← Baseball Bugs ^{What's up, Doc?} carrots→ 21:27, 28 June 2024 (UTC) reply

They had the same attitude in reference to a question about cities in the Arctic back in April. -- User:Khajidha ( talk) ( contributions) 15:48, 2 July 2024 (UTC) reply

In the previous question, instead of any attempt at an answer, I received arguments that anything and everything is a city from New York City to an outhouse sitting next to a gravel road. In this question, instead of any attempt at an answer, I received arguments that Talos is still guarding Crete "In 2024", so it is impossible to refer to a time period when Talos, according to Myth, existed. Long ago, the reference desk attempted to provide references. Now, I attempt to give references and links to supporting information when I answer questions, but when I ask a question, I get pedantic arguments about one word, ignoring the question. 75.136.148.8 ( talk) 13:42, 3 July 2024 (UTC) reply

There is no way to answer a question about "which city" if you do not give us a standard for what you will accept as a city. In the current question there is no way to refer to a time frame for a mythical event. If you can't give us actual, answerable questions, then we cannot give you answers. -- User:Khajidha ( talk) ( contributions) 13:48, 3 July 2024 (UTC) reply

That is my point. Here, you cannot give answers because you get tied up pedantic minutia which does not actually have to do with the answer. On Reddit, they simpy give an answer. The original question was not about cities. It was about limiting the labels on a map to those with higher populations. There is no harm in stating that OpenStreetMap tends to show more populated areas. This question is not about if or if not Talos truly existed and exactly when did he exist. It is about the general time period referenced in the mythology. There is no harm in stating the "Circa" looks better than "About." It gives the impression that the purpose of "answering" is to rationalize reasons why an answer cannot be given, often stating it is "impossible" to answer... unless you ask on Reddit. 75.136.148.8 ( talk) 18:02, 3 July 2024 (UTC) reply

It seems you're looking for a definitive stylistic opinion, which Reference Deskers are less keen on offering than Redditors might be. In any case, as a general audience non-historian, "around 300 BC" sounds perfectly fine to me. "Circa 300 BCE" works too, I don't think it's any more specific per se but I guess it has aesthetic flair. GalacticShoe ( talk) 19:42, 3 July 2024 (UTC) reply

Personally I'd say "Use circa 300BC because more people will understand that (unless your intended audience are all college-educated Americans under say 35, or academics)." Johnbod ( talk) 21:31, 28 June 2024 (UTC) reply

You told us that "Around 300 BC" is boring. Indeed, "Circa 300BCE" is much more exciting! But what does this period refer to? "Circa 300BCE, Talos toured thrice a day around Crete?".  -- Lambiam 00:44, 29 June 2024 (UTC) reply

Look at the article (which boringly uses BC). Johnbod ( talk) 02:16, 29 June 2024 (UTC) reply

June 30 Information

Does anyone know the source of the following quote: "Two augurs cannot walk past each other without smiling". (Since they both know what nonsense their predictions are.) It is associated in my mind with Cato the Elder but I'm not entirely confident. I've checked Wikiquote and it's not there. Leaving aside the attribution, does anyone recall a similar saying? 178.51.74.75 ( talk) 19:50, 30 June 2024 (UTC) reply

Yes, attributed to one Cato or another by Cicero in Book 2 of De Divinatione: "But indeed, that was quite a clever remark which Cato made many years ago: 'I wonder,' said he, 'that a soothsayer doesn't laugh when he sees another soothsayer.'" [13]. (Vetus autem illud Catonis admodum scitum est, qui mirari se aiebat quod non rideret haruspex haruspicem cum vidisset.) [14]. -- Antiquary ( talk) 20:24, 30 June 2024 (UTC) reply

Cicero refers to Cato the Younger earlier in the same book: "I have also recently thrown in that book On Old Age, which I sent my friend Atticus; and, since it is by philosophy that a man is made virtuous and strong, my Cato ¹ is especially worthy of a place among the foregoing books." So it is likely he is referring to the great-grandson. Later he mentions Cato in the list "Cato, Varro, ² Coponius or I?". Varro and Coponius were contemporaries of Cicero, so this also points to Cato the Younger.  -- Lambiam 09:35, 1 July 2024 (UTC) reply

Good points, but when I look on Google Books for attributions from modern Classics scholars I only find them naming Cato the Elder, either by name or as the author of De agri cultura: [15] [16] [17]. Is that solely because in that work Cato the Elder told his steward not to consult haruspices? But others were also rather sniffy about them [18]. I'm left in doubt which Cato Cicero meant. -- Antiquary ( talk) 18:26, 1 July 2024 (UTC) reply

Cato the Younger was younger than Cicero. If "De Divinatione" is from around 44 BC (when Cato the Younger was about 50) what could "many years ago" mean and which of Cato the Younger's books (did he write any?) would have been written early enough in Cato's life and have given Cato an opportunity to say something about diviners? On the other hand is it possible that the "clever remark" may have been oral (either spoken directly or reported to Cicero)? Even if Cato's saying in Cicero's words feels like written Latin, is it possible that Cicero was parphrasing, not reporting it literally? Incidentally there's something intriguing about a deeply traditionalist guy (both Catos were) being skeptical of and even sarcastic about a matter of religion. A mix of pragmatic skepticism and traditionalism seems to fit Cato the Elder better, doesn't it? Traditionalism in Cato the Younger's time seems to have become too demonstrative and ideological for him to allow himself to mock a matter of religion, doesn't it? 178.51.74.75 ( talk) 23:09, 1 July 2024 (UTC) reply

July 1 Information

[19] Macron is the guy with the white shirt, right? Who is the guy in the baseball cap shaking hands with randoms? Another politican? Do I have them confused? And is the PM of France kind of an irrelevant figure? In other countries with PM's I thought it was the other way around, the PM runs things and the president is a figurehead. Thanks. 2601:644:8501:AAF0:0:0:0:9BB0 ( talk) 12:28, 1 July 2024 (UTC) reply

Macron is the person in the leather jacket / the baseball cap, joining Brigitte Macron for part of the take. The guy in the white shirt, shown at the start of the video may be security. -- Cookatoo.ergo.ZooM ( talk) 14:36, 1 July 2024 (UTC) reply

France is a semi-presidential republic, or dual executive republic in which a president exists alongside a prime minister (from Semi-presidential_republic). There are two competitive readings of the French Constitution, see Constitution_of_France. To me, except may be during "cohabitation periods", the usual interpretation is in favor of a "powerful president". — AldoSyrt ( talk) 14:39, 1 July 2024 (UTC) reply

Still, to add to what AlsoSyrt said, the Prime Minister is far from insignificant. Under the previous two Republics, from 1871 to 1958, however, it was the President who was largely a ceremonial figure. Xuxl ( talk) 14:46, 1 July 2024 (UTC) reply

See also Prime Minister of France which says: "The extent to which... decisions lie with the prime minister or president often depends upon whether they are of the same political party. If so, the president may serve as both the head of state and de facto head of government, while the prime minister serves as his deputy". Alansplodge ( talk) 16:33, 1 July 2024 (UTC) reply

Thanks all. The guy in the white shirt (starting at 0:11 in the video) resembles photos of Macron that I've seen, so I got confused. 2601:644:8501:AAF0:0:0:0:9BB0 ( talk) 20:36, 1 July 2024 (UTC) reply

With the current Sup Ct reversing well known earlier decisions, I'm wondering if there are any that it reversed more than once. Like Lawrence v. Texas reversed some earlier decisions, but Justice Thomas proposed that the current court reverse Lawrence v. Texas, so the two reversals would cancel each other out. I'm wondering whether anything like that has actually happened. We have List of overruled United States Supreme Court decisions so maybe I try do a manual self-join, but I figure I'd miss some things, and that such incidents would be known to people into such things. I asked same question in the talk page for that list article before thinking of asking here. That's probably a better place to answer, but if necessary I can relay from here. 2601:644:8501:AAF0:0:0:0:9BB0 ( talk) 20:51, 1 July 2024 (UTC) reply

My question is fairly simple: did 19th-century French author Guy de Maupassant (1850–1893) ever write about or fictionalize a character in his work based upon Suzanne Valadon? I ask, because W. Somerset Maugham biographer Anthony Curtis (1926-2014), in his 1992 introduction to The Razor's Edge (1944), describes Maugham's character of "Suzanne Rouvier" as "straight out of Maupassant". (Curtis 1992). Prior to this, in the same introduction, Curtis describes her character using an almost identical description of the real-life Valadon, however, nowhere does he mention her name. Additionally, we know that Maupassant and Valadon were contemporaries and frequented the Chat Noir at the same time (Snow 1958). One year before Curtis wrote this new introduction, the World Wide Web went public in 1991. Mosaic popularized its usage greatly in 1993, and by 1995, Netscape unleashed the flood gates. Now, here's where things get murky: from what I can surmise, post-1995, an early website creator named "The Wanderling" read Curtis' 1992 introduction, and started promoting the idea on the web that "Suzanne Rouvier was based on Suzanne Valadon". Fast forward to 2024, and all iterations of this claim appear to trace back to "The Wanderling" and his early website. Which brings me back to my original question. What exactly did Curtis mean by Rouvier being "straight out of Maupassant"? Finally, is there any good evidence besides the website created by "The Wanderling", that Rouvier is based on Suzanne Valadon? Thank you. Viriditas ( talk) 21:25, 1 July 2024 (UTC) reply

Note, if anyone wants more intricate details and extended quotations from the above cited works, I have included them at Talk:Suzanne_Valadon#Re:_W._Somerset_Maugham. Viriditas ( talk) 21:28, 1 July 2024 (UTC) reply

"Straight out of Maupassant" may not mean that Maupassant actually put the character in his works. It may also mean that she lives in a universe similar to that described by Maupassant (and Maupassant does describe 1880s French bourgeois society in great detail, including illicit love affairs and the demi-monde of Paris society to which Valadon belonged). It's almost certain that Maupassant would have been familiar with Valadon, as she frequented the same circles as he did, although she did not gain recognition for her art (as opposed to her modeling work) until after he was confined to an insane asylum in 1892. Given that Maupassant wrote over 300 short stories in addition to six novels, it's hard to say if Curtis is referring to a specific character. Xuxl ( talk) 13:51, 2 July 2024 (UTC) reply

Agreed, it means typical of the author's characters or plotlines; see also "straight from Kafka", "straight out of Dickens", "straight out of Steinbeck" and "straight out of Orwell". Alansplodge ( talk) 15:13, 2 July 2024 (UTC) reply

I concur, but I thought I would give it a shot.

Resolved

Viriditas ( talk) 18:12, 2 July 2024 (UTC) reply

Novelists commonly use aspects of people they know (including themselves) for modeling their fictional characters. It is very possible that Maupassant modeled some aspect of some of his characters with Valadon in mind. Independent of what Maupassant may have done, it is also possible, and definitely not per se unlikely, that Maugham used Valadon as a model for his Suzanne Rouvier.  -- Lambiam 19:21, 2 July 2024 (UTC) reply

Of course, but we are trying to source this on the Valadon page, and all I've been able to find are circular references to "The Wanderling" web site, which was published just a few years after Curtis' introduction, hence the connection. I'm curious if anyone tried to connect Valadon with Maugham's character prior to 1992. Viriditas ( talk) 20:35, 2 July 2024 (UTC) reply

July 2 Information

I'd like some decent independent WP:RS about what this org is. [20] [21] [22]. They have a website, but my browser don't think I should go there. Mentioned at List of active separatist movements in Africa. Gråbergs Gråa Sång ( talk) 09:51, 2 July 2024 (UTC) reply

From a quick look it seems to be an initiative created by Ebenezer Akwanga, a separatist from Cameroon who has lived in exile in Nigeria, hence probably the mention in Nigerian sources you link. Whether it is much of a movement, or just an internet platform connecting activists, I am less able to tell. Newsweek reports it is operating from the US. CMD ( talk) 10:28, 2 July 2024 (UTC) reply

Found something: [23] Gråbergs Gråa Sång ( talk) 10:45, 2 July 2024 (UTC) reply

The article Calculator spelling says 8. But this page http://www.hakank.org/upside_down_number_words says 9. Who is right?? Georgia guy ( talk) 21:49, 2 July 2024 (UTC) reply

Uppercase “B” is 8

Lowercase “b” is 9

Blueboar ( talk) 22:04, 2 July 2024 (UTC) reply

Blueboar, that's not what the Wikipedia article says. It says 9 is G. Georgia guy ( talk) 23:07, 2 July 2024 (UTC) reply

You do understand that you are asking for definitive answers about what is basically modern folklore? You might as well ask whether the song is actually hokey-cokey or hokey-pokey. -- User:Khajidha ( talk) ( contributions) 00:59, 3 July 2024 (UTC) reply

It may be that there is a “calculator generation” gap in play, between the blockier “font” of old calculators, and more modern ones that have a more rounded “font”. But ask anyone who was a child in the 1960s what 5319009 spelled when you turned your calculator upside down, and they knew the answer was “bOObIES”… it was the height of 6 year old humor! Blueboar ( talk) 01:03, 3 July 2024 (UTC) reply

In the 1980s it was 5318008. -- User:Khajidha ( talk) ( contributions) 01:28, 3 July 2024 (UTC) reply

Looked at the diagram in our article… and realized that the 9 depicted there has a horizontal bar at the bottom… the calculator I had in the 60s did not. This may account for the difference in tradition. Blueboar ( talk) 01:37, 3 July 2024 (UTC) reply

Upside down, "9" turns into a "6', which in calculator spelling is a lowercase "b".  -- Lambiam 08:11, 3 July 2024 (UTC) reply

A half rotation of a calculator 9 produces Б, at least on Casio and Texas Instruments models. At least in my memory, which is incredibly faulty. Folly Mox ( talk) 11:10, 3 July 2024 (UTC) reply

July 4 Information

I couldn't find any info on the History of pre-electricity lighting in India, Indoor Lighting, Outdoor Lighting, Street lighting, Commercial Building lighting, Royal Residence lighting, Residential lighting, the various equipment used, fuels used, historic records, illustrated historic references like engravings. 2405:201:F00B:3879:D464:2331:428A:6F4D ( talk) 07:28, 4 July 2024 (UTC) reply

Ordinary people often used Oil lamps, as was done in various parts of the world, though an Indian variation on the theme was that Ghee was often used in the lamp. See Diya (lamp), Nilavilakku, and Nachiarkoil lamp... AnonMoos ( talk) 16:41, 4 July 2024 (UTC) reply

In this interview, at the end of 1982, Anthony Burgess mentions having been to "a big magazine conference in Puerto Rico. I had to address the audience there, and being Americans they had to begin every morning with a jog. Two people died of heart failure on this jog who were younger than I. They tried to persuade me to go along on this jog. But in the tropics? In the tropics, even at 6.30 am? Oh no. A couple of people collapsed and apparently died, at least they disappeared. Whether they’re being artificially supported somewhere I don’t know." So what was the conference and who died, or was disappeared? Thank you, DuncanHill ( talk) 19:08, 4 July 2024 (UTC) reply

Language Information

Look up Wiktionary:Information desk in Wiktionary, the free dictionary.

June 22 Information

hello, I dimly remember there existing a %title% and it also had the word "intellectu-all" (sic) in it. Google was no help. Does someone know which poem I mean. Thank you in advance Aecho6Ee ( talk) 03:06, 22 June 2024 (UTC) reply

June 24 Information

I’m only barely cognizant of the Korean alphabet, so this might be an obvious thing, but I noticed that the Korean spelling of Lee Sung Jin is 이성진, but my understanding is that ᄋ in an initial position is an indication of no initial consonant (since a Hangul syllable cannot begin with a vowel). So I’m wondering why 이 is rendered “Lee.” Is that how his name would be pronounced in Korean or is the added initial L a sop to Western expectations who would find a family name of I or Ee to be too short? D A Hosek ( talk) 02:02, 24 June 2024 (UTC) reply

There's a bit more info at Lee (Korean surname). There's still in principle a consonant "ㄹ" at the beginning of the syllable, but Korean phonetics don't pronounce this sound in initial position. The practice in South Korea is that this type of phonetic rule should be reflected in spelling, so it's written "이" instead of "리". In North Korea the spelling is "리" and the name is also transliterated as "Ri", as in Ri Sol-ju. So it's not entirely made up for Western expectations. Other names are also affected by related phonetic rules: for example, Roh Moo-hyun's family name is written "노" in Korean. The same root Chinese character does have an "ㄹ" when it's not at the start of a word. -- Amble ( talk) 03:14, 24 June 2024 (UTC) reply

June 26 Information

Part of me thinks I'm wrong here. InedibleHulk ( talk) 00:16, 26 June 2024 (UTC) reply

Part of you is right. You can only be demobilized from the armed forces. Delisted doesn't sound right either (unless you fell off a tilting ship). I'd go with "resigned", "quit", "left the service" or simply "left". Clarityfiend ( talk) 06:22, 26 June 2024 (UTC) reply

"Demobilization" usually refers to a whole unit being disbanded, at the end of a war or such, not a voluntary individual resignation. AnonMoos ( talk) 07:14, 26 June 2024 (UTC) reply

Several dictionaries disagree with you and say that it can be used for either a unit or a person. [24] [25] Clarityfiend ( talk)

As I remember it from Robert Graves' Good-bye to All That (where he had a rather strange post-WW1 demobilization experience), an individual soldier can "be demobilized" (in the passive voice) to end his wartime service (even if his unit didn't disband), but it wasn't used in the active voice to indicate an individual soldier resigning for reasons that were unrelated to an overall decrease in the size of the military. Usage could have changed since that time, of course... AnonMoos ( talk) 13:49, 26 June 2024 (UTC) reply

So the Hulk was right about being wrong twice. Clarityfiend ( talk) 03:23, 27 June 2024 (UTC) reply

Rather than search for a more appropriate single word (that might not exist), why not substitute a phrase, such as (but not necessarily) "left the service"?

Incidentally, my understanding is that the organisation is properly called the US Merchant Marine (sing.) and that its personnel are mariners, not marines, although not all sources stick rigidly to these forms. {The poster formerly known as 87.81.230.195} 151.227.226.178 ( talk) 18:12, 26 June 2024 (UTC) reply

"Demobilized" suggests that the person was "mobilized" or conscripted in the first place, which seems not to have been the case here (I'm not sure that anybody could be conscripted into the merchant service). Also agree that a merchant seaman or mariner is a better description than marine which usually means a naval infantryman. Alansplodge ( talk) 11:18, 27 June 2024 (UTC) reply

Thanks, everyone. It turns out "left" was the right word all along. For a dockworker, a mariner or anything. InedibleHulk ( talk) 19:52, 27 June 2024 (UTC) reply

You may be thinking of the act of paying off a sailor at the end of a voyage (possibly more used in a UK/Commonwealth/naval context: see also Ship commissioning#Decommissioning), which did not necessarily indicate a change of career. -- Verbarson   ^talk _edits 18:20, 28 June 2024 (UTC) reply

June 27 Information

Courtesy link: Archangel

In the article, someone changed ɑr|k|ˈ|eɪ|n|dʒ|əl|s to ɑr|tʃ|ˈ|eɪ|n|dʒ|əl|s. Is this a valid pronounciation or a mixup due to words like archbishop? Should it be changed back? -- Echosmoke ( talk) 19:12, 27 June 2024 (UTC) reply

Thoughts sorted by particularity (increasing), and therefore by pragmatism (decreasing):

1. I don't really think a pronunciation guide is required for that article.
2. Both pronunciations scan as valid in modern English.
3. The oldest use of the digraph ⟨ch⟩ in Latin-script alphabets like English is actually to transcribe the Greek ⟨χ⟩, whence archangel ← ἀρχάγγελος. So, the most etymological pronunciation in English is with /k/, not conflated with the later but now more ubiquitous use of ⟨ch⟩ used to write /tʃ/.

Remsense 诉 19:27, 27 June 2024 (UTC) reply

Neither OED nor my trusty Collins 20th Century have the |tʃ| pronunciation. DuncanHill ( talk) 20:09, 27 June 2024 (UTC) reply

Aye. I just mean that I wouldn't necessarily notice if someone used /tʃ/ in the flow of conversation, but I've neglected to directly answer that /k/ is much more common in any case. Remsense 诉 20:13, 27 June 2024 (UTC) reply

Before a recent edit, SS London (1864) had "Nineteen people escaped on the life boat ... The London took with her two hundred and forty-four persons." (my bold) Both now read as "people". I preferred the previous wording, perhaps because those who survived did so together, while the victims presumably died separately. However I can't revert just on my sense of nuance. Any ideas? Doug butler ( talk) 22:27, 27 June 2024 (UTC) reply

I think today it's a stylistic toss-up. Merriam-Webster has a discussion on this.

First paragraph:

People should always be used when a collective noun referring to the entirety of a group or nation (i.e., "the French People") is called for. For references to groups of a specific or general number, either people or persons may be used. However, modern style guides tend to prefer people where earlier guides preferred persons, especially for countable groups. OtherDave ( talk) 23:24, 27 June 2024 (UTC) reply

To me, "persons" means fewer persons/people than "people". In particular, I've never run across so many (244) referred to as persons. Also, having both "persons" and "people" so close together in the same paragraph strikes me as rather odd. So, for both reasons, I'm a "people" person. Clarityfiend ( talk) 11:24, 28 June 2024 (UTC) reply

Thank you, much appreciated. Doug butler ( talk) 23:16, 28 June 2024 (UTC) reply

July 1 Information

Where does the expression "pearl-clutching" come from? Lizardcreator ( talk) 00:59, 1 July 2024 (UTC) reply

Before looking it up: when one wears a pearl necklace. it rests in a prime position to be clutched if one brings their hand to their neck or clavicle area, which is a common gesture when flummoxed or offended.

After looking it up: yup. Remsense 诉 01:01, 1 July 2024 (UTC) reply

Wow, thanks for the quick reply! Consider me impressed. Lizardcreator ( talk) 01:30, 1 July 2024 (UTC) reply

This could have been found on Wiktionary: Wiktionary:pearl-clutching#Etymology.  -- Lambiam 08:53, 1 July 2024 (UTC) reply

I find that it is most often used to describe people who would also be described as "busy-bodies" or "biddies". People whose shock and outrage is more for show than real and is often a hypocritical cover for their own bad behavior. -- User:Khajidha ( talk) ( contributions) 11:57, 1 July 2024 (UTC) reply

I suppose that this is inferred by the sort of person likely to wear a string of pearls; Hyacinth Bucket springs to mind. Alansplodge ( talk) 16:38, 1 July 2024 (UTC) reply

I also associate strings of pearls with rather vampy, femme fatale types. Hardly a description that applies to Hyacinth. -- User:Khajidha ( talk) ( contributions) 14:39, 3 July 2024 (UTC) reply

That said, the stereotype is for ladies of a certain age and social standing, even though some vamps may occasionally wear pearls. That is who the saying applies to. Xuxl ( talk) 14:48, 3 July 2024 (UTC) reply