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May 7

Crows (birds) in Adelaide

Are there any birds called "crows" native to Adelaide or nearby regions of South Australia? I'm specifically interested in the common name, not all Corvus species; I know the Australian raven exists there, but I'm not interested in it. Given the existence of the Adelaide Crows AFL club, I assumed the Australian crow was native to the area, but its distribution map disagrees. Google search results are strongly skewed toward the footy club, no surprise. Nyttend (talk) 19:16, 7 May 2025 (UTC)[reply]

That map is clearly mislabeled. It’s called “Native range of Australian crow”, yet the notes reveal it's only about Corvus orru, the Torresian crow, which is native to the areas in red, which excludes all of south-eastern Australia, which is where birds commonly called "crow" are found in great abundance.

From our article crow: A crow is a bird of the genus Corvus, or more broadly, a synonym for all of Corvus. The word "crow" is used as part of the common name of many species. The related term "raven" is not linked scientifically to any certain trait but is rather a general grouping for larger-sized species of Corvus.

In my youth I lived for some time in Wagga Wagga, NSW, whose name was long thought to derive from the local indigenous language to mean "place of many crows". That’s been debunked now, but the point is that crows are extremely common in that part of the continent. Now, exactly what species any individual specimen may be is another question, but the term "crow" encompasses the entire genus, and that is surely what they had in mind when naming the footy club. -- Jack of Oz ^{[pleasantries]} 21:49, 7 May 2025 (UTC)[reply]

The entire genus? The raven is also part of Corvus, but it's a raven, not a crow. Remember that I'm interested in common usage, not biological accuracy. Nyttend (talk) 20:01, 8 May 2025 (UTC)[reply]

You seem to be getting confused: You say you're interested only in common usage (which I've advised you about), yet you're excluding ravens on technical grounds. I've lived my whole life in the white area (plus 10 years in south-eastern Queensland, which may or not sneak in). I can promise you that when anyone who isn't an ornithologist sees one of those black birds, they call them "crows". What ornithologists might call them is irrelevant to your question, according to your own criteria. -- Jack of Oz ^{[pleasantries]} 20:18, 8 May 2025 (UTC)[reply]

No, I'm saying that because ravens are called ravens, I'm not interested in them. Since immigrating to Melbourne, I've been told that we have ravens here, but not crows; I'm looking for species that would commonly be called crows and wouldn't be called ravens. Nyttend (talk) 21:29, 8 May 2025 (UTC)[reply]

But I've been at pains to point out that ravens are commonly called crows. I, for one, have no idea what distinguishes a raven from any other corvid. To me, and to the vast majority of people, they are all the same thing - crows. -- Jack of Oz ^{[pleasantries]} 22:04, 8 May 2025 (UTC)[reply]

Ravens are huge compared to crows, magpies, rooks, jackdaws, choughs, and other crows. Anyway, we do have List of birds of South Australia which @Nyttend: may find helpful. DuncanHill (talk) 22:32, 8 May 2025 (UTC)[reply]

I'm with Jack here. In common usage, across all of the white area of that map (which includes Adelaide) the vast majority of people use the word "crow" to describe all larger black birds. The word "raven" is very rarely used. So the answer to the initial question here is yes. Lots of them! HiLo48 (talk) 00:20, 9 May 2025 (UTC)[reply]

I don't know: this is clearly a "your mileage may vary" kind of situation, but it seems to me that very similar distribution situations exists in numerous other regions around the world with regard to crows and ravens, but that there is typically a strong portion of the general population that recognize that ravens and crows are not the same species, without knowing anything further about the taxonomy--or indeed anything more about the distinction than that raven species tend to be significantly larger than crow species. But I don't have a lifetime worth of experience of Australia to say whether the trend holds there. In any event, I am surprised any of y'all have the time to notice any other birds when you are dealing with nature's perfect asshole, the Australian magpie. SnowRise ^{let's rap} 08:08, 10 May 2025 (UTC)[reply]

Here is a video of a large black bird in Melbourne, designated a "crow". ‑‑Lambiam 08:47, 10 May 2025 (UTC)[reply]

Old saying about bird identification: "A crow in a crowd is a rook, and rook by itself is a crow." PS There very few ravens in the UK, about 7,500 breeding pairs, mostly in Scotland, as opposed to 1 million crows and 1.5 million rooks. MinorProphet (talk) 20:24, 14 May 2025 (UTC)[reply]

May 8

Removal of bones in hand

This question might seem morbid, but in Harry Potter and the Chamber of Secrets, Lockhart accidentally removes the bones in Harry's hand. In real life, what would happen if the bones in your hand suddenly disappeared? Would it be anything at all like what's depicted in the book/film? Lizardcreator (talk) 03:31, 8 May 2025 (UTC)[reply]

It would be like your hand turned into jelly. ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:54, 8 May 2025 (UTC)[reply]

Just like a jellyfish. Stanleykswong (talk) 07:13, 11 May 2025 (UTC)[reply]

There are blood vessels running through an interconnected system of canals in the bone (see Haversian canal and Volkmann's canal). If the magic treats these blood vessels inside the bone as being part of the hand bones and makes all of it disappear together, serious leakage would occur from the suddenly severed ends of these vessels in an analogous disappearance in real life. The local damage may cause most of the nerve cells in the periosteum to fire, causing the real-life Harry to expertience excruciating pain. ‑‑Lambiam 09:08, 8 May 2025 (UTC)[reply]

The remaining blood vessels would not fair much better either, since the connective tissue that normally holds them in place and in tension would lose its anchor points, even as the overall hemostatic balance of the appendage would be immediately disrupted. The precise biomechanics of this odd hypothetical are complicated, but for a certainty the fascia would quickly begin to separate, and blood would quickly begin to pool in the new cavity in rapidly increasing volume--almost certainly in large enough amounts to cause a hemorhagic crisis in a matter of minutes, without immediate intervention, I would think. SnowRise ^{let's rap} 08:31, 10 May 2025 (UTC)[reply]

Since magic was used to remove the bones, magic could also be used to fix these problems. That's the advantage of fiction: Anything can happen. ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:38, 10 May 2025 (UTC)[reply]

Imagination about sudden magical bone loss may extrapolate from known bone disorders estimated to be in increasing order of trauma: Osteoporosis (gradual bone deterioration that commonly leads to fracture especially in the elderly), fibrous dysplasia (a rare disorder of continuous replacement of bone with weak fiber) and Amputation (of the hand either by accident or by deliberate attack of superstitiously prescribed punishment e.g. Islamic Hudud). Those that have undergone these are able to describe their experience while we who are not so qualified should not post speculation here. Philvoids (talk) 21:52, 10 May 2025 (UTC)[reply]

Or it might just be imaginary. ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:11, 11 May 2025 (UTC)[reply]

I'm usually the strongest possible proponent for the no speculation rule here, but this is not exactly a super apt example. For starters, there's not much speculation involved for what would happen if you just spontaneously removed a chunk of tissue for inside the human body, odd as that hypothetical is. Anyone with an degree of background in medicine or physiology can easily tell you what will happen in that situation without recourse to speculation on the broadstrokes: internal hemorrhage and hypovolemic shock. That's because only the method of tissue loss in this case (spontaneous magical excising) is extraordinary. The actual things that happen to the human body after the loss of tissue are, in the broadstrokes, easily predictable. In this case, I couldn't tell you precisely how much of a slurry the internal tissues of the hand would become once those bones were removed all at once, but I can tell you that the overall medical crisis that would ensue would be akin to the last of your listed scenarios, amputation. Also, I'd note that there's an error in your reasoning: just because someone has experienced the sensorial qualia that comes with an osteopathology does not mean that they have special insight into the physiological features of that condition, let alone the ability to be especially informative about what would happen with a completely unrelated acute trauma. The OP's question seems to me to be directed at the biophysical consequences in such a scenario, not the somatosensory experience. I could be wrong about that though, as I do not have first hand knowledge of how this fantastical situation is presented in the referenced movie. SnowRise ^{let's rap} 04:48, 11 May 2025 (UTC)[reply]

Invertebrates such as octopuses, earthworms and slugs have no bones. They do not rely on an internal skeleton, but instead use muscles for support. So if the bones in your hand suddenly disappeared, you would probably still be able to move your thumb and fingers if your muscles, ligaments, and tendons were strong enough to support your body. Stanleykswong (talk) 07:13, 11 May 2025 (UTC)[reply]

I recognize that this is probably trolling in light of the above discussion, but no--that is absolutely not something that might happen. Invertebrates like cephalopods and other molluscs have evolved their musculature and fascia in the context of lacking an endoskeleton, and thus have other means of producing biomechanical leverage. The muscles and connective tissues of vertebrates--human beings included--on the other hand, function in complete reliance upon the skeleton to provide not only just fulcrum points to enable mechanical flexion, but also just to maintain their normal homeostatic tension and position. In no way could even the smallest and most isolated muscle groups of the hand provide anything like their normal functioning in the absence of bone. And that completely ignores the facts already discussed above about how any spontaneous removal of the bone from the hand would also immediately destroy innervation and vascular and metabolic function, as well as create immediate and significant trauma. No matter how well developed or "strong" your muscles were, if the bones in your hand immediately disappeared, you would not have a magical octopus hand: you would have a rapidly swelling blood sack at the end of your arm, and a medical crisis that could be averted only with immediate surgical intervention to amputate what remained of your hand. SnowRise ^{let's rap} 03:02, 12 May 2025 (UTC)[reply]

Or with additional magic. ←Baseball Bugs ^{What's up, Doc?} carrots→ 11:32, 12 May 2025 (UTC)[reply]

If we assume it is a magic, it should have all the power to make it work. This means that all innervation, vascularity and metabolic functions remain intact and muscle development occurs simultaneously. Stanleykswong (talk) 16:33, 12 May 2025 (UTC)[reply]

If we assume it is a science, then you cannot use your imagination to imagine things that are impossible in the real world, such as magic. In this case, we should realize that it is impossible to accidentally remove bones from a hand. Stanleykswong (talk) 18:04, 12 May 2025 (UTC)[reply]

Is fiction a science? ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:49, 12 May 2025 (UTC)[reply]

No, fiction is not science. Some fictions, like Star Trek, do draw inspiration from scientific concepts and explore them, but they are still fiction. Stanleykswong (talk) 20:51, 12 May 2025 (UTC)[reply]

Perhaps so, but I am trying to meet the OP half way here. It seems to me that, despite the fantastical and impossible starting point of their inquiry, they are genuinely trying to understand some things about physiology. Spontaneously teleporting the bones of the hand through sorcery is clearly not something that anybody ever has to worry about, but as a thought experiment, the answers to their question can actually be very informative about the anatomy of the hand and the functioning of various of the body's homeostatic systems. We're certainly pushing right up against the edge of what the Reference Desks are meant for by indulging the question, but I consider it inside the circle of relevant topics and a worthwhile conversation, provided they are sincere in their curiosity and getting something out of this. On the other hand, trolling them by suggesting their hand can function without bones accomplishes nothing productive. SnowRise ^{let's rap} 20:38, 12 May 2025 (UTC)[reply]

May 10

Do cops use signal jammers on video doorbells belonging to suspects?

If any Wikipedian here is a cop IRL, please answer here.

If the police are to visit someone's house for a questioning, a raid or to serve a warrant, do they jam the signal to their video doorbell so that the suspect monitoring the doorbell with their smartphone doesn't get tipped off about the cops' presence this way?

If the suspect is not home for whatever reason, and they see that cops are at the door through their video doorbell's camera feed, they may stay somewhere else until the cops go away, or flee the area and disappear from the law.

Or if they're home, and for example, they have to get rid of their drugs, they flush them down the toilet as soon as they see cops on the video feed before they answer their door.

So do you jam their video doorbell's signal when you get to their door?

Or do you let yourselves be seen on their video doorbell?

Also, if their voice comes on the speaker and says "I'm not home, what do you need?" What is your response right then?

If you're wondering "Why are YOU worried about this?" Great question; it's because I, a member of the Anti-Trump Establishment, am paranoid that Trump will soon dismantle democracy and make criticizing and dissing him a criminal offense, even retroactively. I've already posted criticisms of him on social media, so that could be why the cops will someday pick me up, along with millions of other outspoken anti-Trump citizens.

Even though I'll *gladly* go to jail for dissing and criticizing our idiot president, since Democratic employers will be MORE likely to hire me due to seeing THAT on my criminal record, I'll likely drive somewhere else if I see through my doorbell's video feed that the cops show up at my apartment for this reason, while I'm away from home. --2600:100A:B03E:F83A:1168:850E:68A3:D675 (talk) 01:25, 10 May 2025 (UTC)[reply]

Once state security organizations in authoritarian states have reached a certain competence level, I don't think you need to worry about details like this. And in my part of the world, fleeing the area doesn't work because states turn a blind eye to each other's extraterritorial operations. They just pick people up or disappear them wherever and whenever it suits them, and they have all the best zero-click toys to put on smartphones. On the plus side, in the US context, southern Libya is very beautiful, if you like deserts. Sean.hoyland (talk) 06:11, 10 May 2025 (UTC)[reply]

If cops are raiding a house they don't bother with niceties like ringing the doorbell. After covering all escape routes they simply bash the door in without warning. Shantavira|^{feed me} 08:49, 10 May 2025 (UTC)[reply]

Speaking of "Democratic employers", have you not thought of the fact that IF America becomes a right-wing dictatorship like you suggest it might, there WON'T BE any "Democratic employers" left to hire you because THEY would all have been arrested as well??? 2601:646:8082:BA0:8C26:9877:F0E8:7F58 (talk) 09:42, 10 May 2025 (UTC)[reply]

I've heard that tinfoil hats deflect those ethereoplasmatic waves. 136.56.165.118 (talk) 00:06, 13 May 2025 (UTC)[reply]

Keeping a crown sheet covered

Follow-up to my earlier question: when driving a steam locomotive (possibly, but not necessarily, a Black Five like I was asking about in my earlier question) in mountainous terrain, what is the minimum water level in the boiler (in terms of percent above the lowest permissible mark on the water gauge) below which there exists a danger of uncovering the crown sheet of the firebox (which can be very dangerous)? Is it true, for example, that you're completely safe if you keep the water gauge above 50%, even if you go from a 2% climbing grade to a 2% descending grade (e.g. when cresting Binegar Summit)? 2601:646:8082:BA0:8C26:9877:F0E8:7F58 (talk) 09:51, 10 May 2025 (UTC)[reply]

That varies a lot from one locomotive to the next. I've seen some locomotives or steam railcars with vertical or even transverse boilers (one in the museum in Luzern) to avoid the issue. It also depends on the gradient expected. There's no need to keep the crownsheet safe when going from 20‰ up to 20‰ down if you're never going to encounter anything steeper than 12‰ (in Europe, rail gradients are usually expressed in permille; Americans use percents; the British use one-in-x ratios). The highest risk is for the Long Boiler locomotives, with long and thin boilers. PiusImpavidus (talk) 16:29, 10 May 2025 (UTC)[reply]

BTW, accelerations also affect the apparent boiler water level. Braking at 0.5 m/s² has the same effect as a short 50‰ downhill, causing the water to slosh forward in the boiler. I suppose it may last too short to overheat the crownsheet and melt the fusible plugs.

Simply put (simply, because it approximates the boiler as a box), the change in gradient times half the length of your boiler equals the change in water depth over the crownsheet. Going from +20‰ to -20‰ with a 6 metre boiler will cause a drop of about 12 centimetres. Your typical sight glass is, maybe, 20 centimetres. PiusImpavidus (talk) 11:02, 12 May 2025 (UTC)[reply]

In 1953, a Chesapeake and Ohio class H-8 (much larger than your Black Five, with four times the tractive effort) exploded at Hinton, West Virginia because the crown sheet ruptured, and the Interstate Commerce Commission produced a detailed incident report. It's too technical for me to know whether it answers your question well, but perhaps you will understand it. Nyttend (talk) 21:03, 12 May 2025 (UTC)[reply]

The report mentions that the boiler water level had dropped to 71⁄4 in (18 cm) below the highest point of the crown sheet (page 6). The lowest point of the water glass was 61⁄2 in (17 cm) above the highest point of the crown sheet (page 9) and the glasses where 61⁄2 in (17 cm) tall (page 8). A low water alarm (not present on most classes of steam locomotives) was activated when the water level dropped to less than 63⁄4 in (17 cm) above the crown sheet top (page 11). Apparently, a witness told that the low water alarm sounded 11⁄2 mi (2.4 km) before the accident (page 13), the injector was closed but in good condition (page 9) and over the past days, problems with one of the feedwater pumps had been reported frequently (page 12), inluding at a stopover 2:30 hours before the accident (page 13). No mention is made of fusible plugs. Not all locomotives were fitted with those, but most were. The accident happened on level track.

The length of the boiler was 23 ft (7.0 m) firetubes + 118 in (3.0 m) combustion chamber + 180 in (4.6 m) firebox equals 574 in (14.6 m), so tilting it from +2% to -2% causes a drop in water lever over the crown sheet of around 3 dm (1 foot). PiusImpavidus (talk) 10:21, 13 May 2025 (UTC)[reply]

Your numbers do make sense for the gross oversimplification of a boiler as a rectangular box, but it sounds like it would have been very dangerous if this had actually been the case -- the boiler would go from completely full to almost empty at the top of every mountain summit (BTW, on some American lines the ruling gradient is as steep as 3% -- 1 in 33 to you -- which would make these fluctuations even worse by half), so there would have been boiler explosions just about every day! Fortunately the top of a boiler is not a vertical-sided rectangular box, but a circular arc with a quite small central angle (which causes its width to decrease very rapidly with height above mean water level) -- would you say this mitigates the above effect by at least half (or maybe by even more than that, like maybe a factor of 3-5)? 2601:646:8082:BA0:499E:7EB5:39D0:497E (talk) 05:10, 15 May 2025 (UTC)[reply]

The accident report above mentions that the diameter of the boiler (back side; it's slightly conical) is 106 in (270 cm) and the bottom of the water glass is 25 in (64 cm) above the axis of symmetry. That means that the width of the boiler at the top of the crownsheet is 99 in (250 cm), at the bottom of the water glass 93 in (240 cm) and at the top of the water glass (still 21.5 in (55 cm) below the top of the boiler) it's 85 in (220 cm) wide, a change of just 15%. When pitching from +20‰ to 0‰, the water depth over the crownsheet drops a bit faster than in the linear approximation, going from 0‰ to -20‰ it drops a bit slower than the linear approximation. In other words, for a symmetric change in gradient, the quadratic term cancels. I'm pretty sure that my gross oversimplification is accurate to within 10%.

There are two additional factors that prevent boiler explosions. First, at mountain passes, the gradient doesn't instantly change from maximum up to maximum down. There's a short stretch of level track between, maybe no more than a passing loop. There, the boiler can be filled if necessary. If the water is very low, the train may even stop there to fill the boiler. Second, the fireman (who's responsible for managing boiler water level and fire) must always take into account not only the current gradient, but also the gradients expected over the next fifteen minutes. He (always he; those were sexist days) has to know the track.

On steep routes, they always used a locomotive designed for steep routes. Driver and fireman must always be familiar with the route; if not, they are accompanied by someone who is.

BTW, it's 30‰ to me. I'm from the European continent (as you might have guessed from my previous comments and less than perfect English skills). It's pretty steep. One of the main railway lines across the Alps, the Gotthard Railway, completed in 1882, has a ruling gradient of 27‰. At the summit, there's a 15 km (9.3 mi) practically level section in a tunnel. Steam operation proved problematic, so the line was electrified in 1920. PiusImpavidus (talk) 18:26, 15 May 2025 (UTC)[reply]

OK, so am I to understand that the boiler must be completely topped off as you cross the summit, and that being even 10-15% low on the water glass as you go over the top can be dangerous? (Also, regarding all firemen back in the day being men: this wasn't only due to sexism, this was also because stoking a steam train (as well as driving one) is very physical work, which is why you don't often see women on the footplate of a steam train even today!) 2601:646:8082:BA0:2C:610F:A84:CB25 (talk) 02:22, 18 May 2025 (UTC)[reply]

May 12

Carbon dioxide poisoning

The Lake Nyos disaster occurred because a lake emitted a huge cloud of carbon dioxide, which spread around the lake and suffocated man and beast in the surrounding area. To my surprise, it mentions occasional effects of poisoning with carbon dioxide, but very little. (I anticipated that a cloud of pure carbon dioxide would be dangerous only because it doesn't contain breathable oxygen, so it would asphyxiate you just as if you were strangled or drowned.) Do we have any article that covers the effects of acute carbon dioxide poisoning like this? Carbon dioxide poisoning is a redirect to hypercapnia, which concentrates on problems when diving and medical problems that can cause excess carbon dioxide more gradually; I know about decompression sickness affecting divers, so I'm left wondering if hypercapnia#physiological effects would still apply in a situation with normal air pressure, or if it's still relevant for people in whom extreme amounts of carbon dioxide are not the result of a pre-existing medical problem. Nyttend (talk) 20:52, 12 May 2025 (UTC)[reply]

The section Hypercapnia#CO2 toxicity in animal models, after discussing experiments on dogs with a 50% air/CO₂ mix, goes on to say:

"At higher concentrations of CO₂, unconsciousness occurred almost instantaneously and respiratory movement ceased in 1 minute. After a few minutes of apnea, circulatory arrest was seen. These findings imply that the cause of death in breathing high concentrations of CO₂ is not the hypoxia but the intoxication of carbon dioxide."

In Carbon dioxide#Toxicity we have:

"In humans . . . Concentrations of more than 10% may cause convulsions, coma, and death. CO₂ levels of more than 30% act rapidly leading to loss of consciousness in seconds."

but also

"Because it is heavier than air, in locations where the gas seeps from the ground (due to sub-surface volcanic or geothermal activity) in relatively high concentrations, without the dispersing effects of wind, it can collect in sheltered/pocketed locations below average ground level, causing animals located therein to be suffocated. Carrion feeders attracted to the carcasses are then also killed. Children have been killed in the same way near the city of Goma by CO2 emissions from the nearby volcano Mount Nyiragongo. The Swahili term for this phenomenon is mazuku."

while further on under Ventilation:

"In February 2020, three people died from suffocation at a party in Moscow when dry ice (frozen CO₂) was added to a swimming pool to cool it down. A similar accident occurred in 2018 when a woman died from CO₂ fumes emanating from the large amount of dry ice she was transporting in her car."

It would seem that both toxicity/intoxication and suffocation may be involved, each separately fatal. The references for those passages (which I have omitted here) may give more details. I speculate that the lack of more explicit details may reflect a paucity of research simply because encountering high levels (tens of percent) of CO2 is for humans an extremely rare occurrence (though it is commonly used in animal euthanesia). {The poster formerly known as 87.81.230.195} 94.2.101.226 (talk) 00:51, 13 May 2025 (UTC)[reply]

During the Apollo 13 disaster, the astronauts were at one point exposed to acutely toxic CO2 levels due to malfunctioning scrubbers: https://www.youtube.com/watch?v=FgJU6Vz1XOs 2601:646:8082:BA0:499E:7EB5:39D0:497E (talk) 06:15, 15 May 2025 (UTC)[reply]

May 13

Fluid in vagina upon sexual arousal

When you finger a girl's vagina and it becomes wet, what is the name for the fluid that you feel in there? 2601:18A:C500:E830:DDE4:FB37:5AA9:F249 (talk) 04:15, 13 May 2025 (UTC)[reply]

Vaginal lubrication is a naturally produced fluid during sexual arousal. It is produced by the Bartholin's gland and/or Skene's gland. Adding the comfort of a Personal lubricant is often appreciated particularly by women affected by vaginal dryness. Philvoids (talk) 08:32, 13 May 2025 (UTC)[reply]

Physics and category theory

Would Category theory help explain relativity and quantum mechanics?Rich (talk) 04:54, 13 May 2025 (UTC)[reply]

The articles Theory of relativity and Introduction to quantum mechanics give well-written introductions to present knowledge and its history. No final consensus has been reached on Interpretations of quantum mechanics or the sought-after Theory of everything to unify general relativity and quantum mechanics. Category theory offers math tools to frame the problem but is not helpful to a newcomer. Philvoids (talk) 08:51, 13 May 2025 (UTC)[reply]

John C. Baez and Aaron Lauda have applied category theory to these topics:

John C. Baez, Aaron Lauda. "A Prehistory of n-Categorical Physics", Chapter 1 of Deep Beauty, pp. 13–128, Cambridge University Press, 2011.

A preprint on arXiv can be accessed here. ‑‑Lambiam 10:12, 13 May 2025 (UTC)[reply]

Hawthorne Math and Science Academy

Is there any evidence that the Hawthorne Math and Science Academy really had a founding principal named Pete Zahut? It sounds like a bad pun based on Pizza Hut, and I can't find any more references to him on the Web, through googling. 2601:644:4301:D1B0:9CFA:E37B:87FE:E7A7 (talk) 18:09, 13 May 2025 (UTC)[reply]

Looks like the name was changed by an IP editor in This 2018 edit claimed as a typo correction. Seems likely to me that it's simple vandalism. I've gone ahead and corrected the name to the one included prior to that user's edit. Amstrad00 (talk) 18:49, 13 May 2025 (UTC)[reply]

Just...wow. I checked out that IP, and in this edit, they claim "Fixed grammar", when in reality it's straight-out vandalism. 2601:644:4301:D1B0:9CFA:E37B:87FE:E7A7 (talk) 08:41, 14 May 2025 (UTC)[reply]

I like your metaphor! 2A02:C7C:3764:A900:9029:B30E:9054:574 (talk) 13:06, 14 May 2025 (UTC)[reply]

"Pete Zahut", eh? Sounds like a cousin of Jabba. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:45, 14 May 2025 (UTC)[reply]

May 14

Origin of the Moon

What is stopping us from having a solid understanding of the origin of the Moon and resolving the unsolved problems? Is it just the fact that we really haven't been studying it all that long and it takes time? Could new tools help resolve the competing theories and definitely say one way or the other? Or will we never know without a fictional time machine or wormhole viewer to look back into the past? Could we (or have we) spotted a moon forming elsewhere in deep space? Viriditas (talk) 09:06, 14 May 2025 (UTC)[reply]

For a time machine to be helpful, it would need to be an actual time machine. A major issue is that current hypotheses fail to explain some known observations, so new ideas seem to be needed. Additionally, the predictive power of these hypotheses is limited, partly because they are incomplete theories giving rise to fuzzy predictions, and partly because some theoretical predictions cannot be tested with available means (similar to how we do not know how to experimentally test hypotheses about the composition of Earth's inner core). ‑‑Lambiam 10:34, 14 May 2025 (UTC)[reply]

Gerotranscendence

There used to be a wiki article on Gerotranscendence. Why was it deleted? Cerebrality (talk) 14:45, 14 May 2025 (UTC)[reply]

It was deleted in 2008 (!), with "was a very short article providing little or no context" [1] --Wrongfilter (talk) 14:55, 14 May 2025 (UTC)[reply]

(edit conflict) If like me you've never encountered the word see Harald Ofstad (note 4). 2A00:23C7:2B60:8401:74ED:7F23:A69C:1530 (talk) 15:03, 14 May 2025 (UTC)[reply]

Looking it up on Google, I would see it as a fancy-schmancy word for "getting nicer as you get older". Which does not always happen. Some folks get meaner as they get older. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:43, 14 May 2025 (UTC)[reply]

You misunderstand it. Not all elderly people experience gerotranscendence, just some. Cerebrality (talk) 19:38, 14 May 2025 (UTC)[reply]

Yes. Some do, and some don't. ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:42, 14 May 2025 (UTC)[reply]

No the article was available until the past few years or so. Cerebrality (talk) 19:38, 14 May 2025 (UTC)[reply]

THe logs don't lie. Maybe there was nothing in it that wasn't already in the Harald Ofstad article? ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:45, 14 May 2025 (UTC)[reply]

embryology

Apologies if this question has been addressed before, but if so I couldn't locate it.

How does the developing embryro distinguish its left from its right side?

For instance in humans how does it know to grow the liver (mostly) on the right side & the spleen (entirely) on the left? Obviously this isn't an infallible process since very ocasionally there can be revesals, which evidently still result in a viable individual - although in later life they might confuse a surgeon.

Do we know if there's any connection with this and differences at a molecular level (L-amino acids & D-sugars)? Renshaw 1 (talk) 18:25, 14 May 2025 (UTC)[reply]

See Situs solitus § Development. If indeed the unidirectional rotation of nodal cilia establishes the usual situs, the next question is why these cilia don't rotate clockwise. This can only be due to chirality of the axonemal dynein (the dynein motor protein animating the cilia). So this is, ultimately, a difference at the molecular level. ‑‑Lambiam 19:15, 14 May 2025 (UTC)[reply]

Aside: It looks like you're the same user as Paul Renshaw. You only need one ID here. ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:19, 14 May 2025 (UTC)[reply]

No, we're different users: I am David Renshaw (but Paul and I have a lot in common). Renshaw 1 (talk) 10:31, 15 May 2025 (UTC)[reply]

What is the name of the manoeuvre when a bird performs an aileron roll in flight?

Because birds don't have ailerons. But they do perform aileron rolls if something comes at them from above. They strike with claws and beak when inverted and then attempt to spiral away. 146.200.107.90 (talk) 22:49, 14 May 2025 (UTC)[reply]

The Aileron article indicates that birds do, in fact, have ailerons. ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:41, 14 May 2025 (UTC)[reply]

I see the term "barrel roll" used for a manoeuvre that, as described, is probably the avian equivalent of an aileron roll: [2], [3], [4], [5], [6]. ‑‑Lambiam 08:40, 15 May 2025 (UTC)[reply]

Am guessing this is typically used only by raptors and not by these or these? Martinevans123 (talk) 08:46, 15 May 2025 (UTC)[reply]

As I understand it, an aileron roll is performed with the aircraft following a straight path. In the reference frame of the pilot, apparent gravity makes a full rotation in the plane perpendicular to the longitudinal axis of the aircraft. The pilot has to operate elevators and rudder to perform the trick. A barrel roll is performed at more or less constant angle of attack, sending the aircraft along a helical path, along the surface of a barrel, with the rudder centred and the elevator slightly up. In the pilot's reference frame, apparent gravity constantly points more or less down. Barrel rolls are relatively safe and easy in non-aerobatic aircraft; the largest type I know to have performed a barrel roll is the Boeing 707. PiusImpavidus (talk) 10:50, 15 May 2025 (UTC)[reply]

Birds use wing warping instead of ailerons. So did the Wright brothers. You can call the manoeuvre a roll. PiusImpavidus (talk) 10:33, 15 May 2025 (UTC)[reply]

May 15

Age of grafts

Does a plant graft have the same age as the original plant? In other words, will it get old when the "donor" organism becomes old? Thanks in advance for the answer! 62.73.72.3 (talk) 21:01, 15 May 2025 (UTC)[reply]

Well, the original Granny Smith apple is from 1868. It's propagated by grafts. The Roxbury Russet is from the mid 1600s. Abductive (reasoning) 21:10, 15 May 2025 (UTC)[reply]

The original Granny Smith apple is from 1868, but that doesn’t mean the grafted tree is 157 years old. The newly grafted Granny Smith apple plant you purchase from garden center or supermarket may only be a few years old because it was cut from a new growth that occurred one or two years ago and that had been joined to a rootstock of a few years old. Stanleykswong (talk) 07:05, 17 May 2025 (UTC)[reply]

That was the point of my response. Abductive (reasoning) 16:46, 17 May 2025 (UTC)[reply]

Plant senescence of perennials is not well understood. Some clonal tree colonies appear to keep living indefinitely, as long as environmental conditions remain good. ‑‑Lambiam 08:52, 16 May 2025 (UTC)[reply]

This depends on which part of the plant is being grafted. If you cut off the main trunk (which usually doesn't happen), the grafted plant will be the same age as the original plant. However, if you cut off a branch that grew two years ago, the grafted plant will only be two years old. Stanleykswong (talk) 06:52, 17 May 2025 (UTC)[reply]

I wonder if grafting a small piece of an ancient bristlecone pine onto a young pine tree would work. If it did, the graft would be a couple thousand years older than its host. ←Baseball Bugs ^{What's up, Doc?} carrots→ 14:41, 17 May 2025 (UTC)[reply]

Most (though not very) likely to work with a stock of Pinus nelsonii. {The poster formerly known as 87.81.230.195} 94.1.170.37 (talk) 16:12, 17 May 2025 (UTC)[reply]

Why that species? Abductive (reasoning) 16:48, 17 May 2025 (UTC)[reply]

Because according to both phylogenies in the Pine article, that's the species most closely related to the three Bristlecone pine species, though it's also described in its own article as "not closely related to any other pines in either morphology or genetics", hence my "Most (though not very) likely".

Apparently, although from a very small and remote natural range, P. nelsonii seeds are so edible and tasty that they're sold in Mexico City markets, and the tree is sometimes cultivated elsewhere out of curiosity, so it should be available commercially if anybody wants to try the experiment. {The poster formerly known as 87.81.230.195} 94.1.170.37 (talk) 00:36, 18 May 2025 (UTC)[reply]

May 16

Hycean planet being a exoplanet or dwarf planet

OP is a block evader

The following discussion has been closed. Please do not modify it.

This article says that hycean planet is a exoplanet and considered to be part of ocean world. But I'm not sure that if this planet is a dwarf planet. Can you tell me what is this planet classify as? Just for this, is this size of the hycean planet small or large? 2600:1700:78EA:450:75E5:23D1:5B65:DBB4 (talk) 05:52, 16 May 2025 (UTC)[reply]

The article actually says "They are usually considered to be larger and more massive than Earth." So, Earth is not a dwarf planet and words like "massive" are not usually used to describe small things. 196.50.199.218 (talk) 06:45, 16 May 2025 (UTC)[reply]

A dwarf planet is defined by its inability to clear the neighbourhood. Abductive (reasoning) 07:54, 16 May 2025 (UTC)[reply]

Just to clarify: hycean planet is a hypothetical type of planet just like rocky planet is a type of planet. It is not a specific planet. Joe vom Titan (talk) 10:49, 16 May 2025 (UTC)[reply]

May 17

Google translate

(Please correct me if this is not the right place to ask this.)

Is Google Translate a reliable enough source for translating common names from other languages to English? For example, if I were to write an article about a plant native to a non-English country, and it has a common name in that language (which is provided, without translation, in a reliable source) – would it be fine to provide a translation, citing Google Translate as a source, or would I have to use something else (or not provide translation at all)? 🌳 Balsam Cottonwood (talk) ✝ 23:36, 17 May 2025 (UTC)[reply]

At best, Google Translate would give a search term to try out. Fortunately, there are sources that list common names for many languages. For starters, there is our own Wikidata and Wikispecies, and there is EPPO. Take a look at all the common names for Quercus suber in its EPPO listing. Also, please drop by WP:WikiProject Plants, unlike many Wikiprojects it is quite active. Abductive (reasoning) 23:48, 17 May 2025 (UTC)[reply]

Sorry, I don't mean finding names in different languages – I already found those at the website you mentioned. I'm just asking if it would be all right to take those names and translate them into English with Google Translate, so I can list names in other languages in the article, with the translations. 🌳 Balsam Cottonwood (talk) ✝ 23:54, 17 May 2025 (UTC)[reply]

Ah, the general consensus that I have observed is that foreign common names are not considered to be particularly encyclopedic. I rarely add them to articles that I create, here are two examples where I do; Celtis biondii and Acer diabolicum. Note that the names are only for the language spoken where the plant is native, and that they provide some useful context for the English readership. In other words, if the names are considered important enough to be analyzed by independent secondary sources, then they can be in the article. Just like everything else on Wikipedia. Abductive (reasoning) 00:13, 18 May 2025 (UTC)[reply]

Okay, thanks. 🌳 Balsam Cottonwood (talk) ✝ 00:15, 18 May 2025 (UTC)[reply]

If a local vernacular name is considered encyclopedic, it is reasonable to provide it with a translation, if available. But one should not trust Google Translate to give a correct translation of such names. For example, Google Translate as it is today turns the Dutch vernacular name Groot akkerscherm for Ammi majus into "Large field screen". But the meaning of scherm in the compound noun akker + scherm is "umbel". For another example, Google Translate inexplicably turns Persian صنوبر کالیفرنیایی (Populus trichocarpa) into "Californian spruce", instead of "Californian poplar". See also Help:Translation § Machine translation and Help:Translation/Machine translation errors. ‑‑Lambiam 11:25, 18 May 2025 (UTC)[reply]

Example: I once pasted a Spanish phrase into Google Translate to translate it into English. It translated "manzana" as "apple" even though in context it clearly meant "block". -- Avocado (talk) 16:25, 18 May 2025 (UTC)[reply]

Google Translate is useful as a guideline, but falls short of being reliable. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:25, 18 May 2025 (UTC)[reply]

Kind of like Wikipedia. Or anything else, for that matter. Matt Deres (talk) 17:25, 18 May 2025 (UTC)[reply]

Okay, thank you, @Abductive, @Lambiam, @Avocado, @Baseball Bugs, and @Matt Deres for your answers. I understand; Google translate is somewhat like a Large Language Model, and is not very reliable. Could I provide a translation if I'm able to find it recorded in a reliable source? The specific article is Anthemis tomentosa, which I wrote yesterday (today in UTC time). Also, I should probably replace the translations in Anthemis brachycarpa, which was published as an article a few weeks ago, because I used Google Translate there. Thanks for all the help! 🌳 Balsam Cottonwood (talk) ✝ 18:09, 18 May 2025 (UTC)[reply]

In any case, they should not be in the article unless verified in a more reliable way.

All uses I see of קחוון קצר-פירות have קחוון with a double ו, so I'm not sure that the ktiv menuqad קַחְוָן קְצַר-פֵּרוֹת with a single ו is not a typo. Like brachycarpa, Hebrew קצר-פירות means "short-fruited" (the second component from פרי, "fruit").

BTW, Turkish sahil papatyası literally means "shore chamomile" (or "(river) bank chamomile"; the Turkish term sahil can refer to the edge of land adjacent to any body of water, so the best translation may dependent on where this flower grows). ‑‑Lambiam 20:08, 18 May 2025 (UTC)[reply]

Okay, thank you. 🌳 Balsam Cottonwood (talk) ✝ 02:04, 19 May 2025 (UTC)[reply]

May 19

Does Wikipedia contain a contradiction about whether, the speed of light is only constant in inertial frames of reference?

On the one hand, our article special relativity states:

In the lead: "The speed of light in vacuum is the same for all observers, regardless of the motion of light source or observer".
In the chapter background: "Two observers in relative motion receive information about two events via light signals traveling at constant speed, independent of either observer's speed".
In the chapter History: "James Clerk Maxwell presented a theory of electromagnetism...The theory specifically predicted a constant speed of light in vacuum, no matter the motion (velocity, acceleration, etc.) of the light emitter or receiver."
In the chapter Reference frames and relative motion: "the speed of light is constant in relativity irrespective of the reference frame".

.

So it seems that the speed of light is constant, also in non-inertial frames of reference.

.

On the other hand, that article also states:

In that chapter: "light in vacuum propagates with the speed c (a fixed constant, independent of direction) in at least one system of inertial coordinates".
In the chapter Basis: The two postulates both concern observers moving at a constant speed relative to each other.
In the chapter Lack of an absolute reference frame: "the speed of light in vacuum is always measured to be c, even when measured by multiple systems that are moving at different (but constant) velocities".
in our article Postulates of special relativity, in the chapter Postulates of special relativity: "As measured in any inertial frame of reference, light is always propagated in empty space with a definite velocity c that is independent of the state of motion of the emitting body. Or: the speed of light in free space has the same value c in all inertial frames of reference".
In our article speed of light, in the lead: "Albert Einstein postulated that the speed of light c with respect to any inertial frame of reference is a constant...Such particles and waves travel at c regardless of the motion of the source or the inertial reference frame of the observer".
In that article, in the chapter Fundamental role in physics: "The speed at which light waves propagate in vacuum is independent both of the motion of the wave source and of the inertial frame of reference of the observer...In non-inertial frames of reference (gravitationally curved spacetime or accelerated reference frames), the local speed of light is constant and equal to c, but the speed of light can differ from c when measured from a remote frame of reference".

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So it seems that the speed of light is only constant in inertial frames of reference.

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I wonder if the second set of quotes contradicts the first one. HOTmag (talk) 19:04, 19 May 2025 (UTC)[reply]

The implicit assumption in the first set is that the observer shares the frame of reference with the measuring instrument. ‑‑Lambiam 12:08, 20 May 2025 (UTC)[reply]

May 20

Is there such a thing as a "heavy gunner" in real life?

You see this in video games a lot. A soldier who is dressed head to toe in a thick kevlar suit/helmet and ballistic plates shooting an LMG or a gattling gun. Often sent out in front of everyone else to cause as much damage to the enemy as possible while standing there and enduring their return gunfire. Does this exist in real life? 146.200.107.90 (talk) 01:58, 20 May 2025 (UTC)[reply]

Only the ones who ride rhinoceri. ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:42, 20 May 2025 (UTC)[reply]

Even if the bullets don't penetrate the armor, their momentum is transferred to the lone vanguard soldier (see Physics of firearms § Transfer of energy). The momentum of a bullet fired by an AK-47 is about 6 kg⋅m⋅s⁻¹. (See the info box, Ballistic performance, of 7.62×39mm; this supposes that the bullets don't bounce back, otherwise the imparted momentum is higher.) At 10 rounds per second, the effect of one rifle on automatic continually hitting its target is an effective force of 6 kg⋅m⋅s⁻¹ × 10 s⁻¹ = 60 kg⋅m⋅s⁻², about 6 g. For a lighter machine gun like the Colt IAR6940 I still get some 4.5 g. The warrior will have a hard time advancing. ‑‑Lambiam 11:44, 20 May 2025 (UTC)[reply]

In real life this would be a suicidal tactic, so not one that would be routinely planned for by officers, or willingly performed by most soldiers. A few unusually brave individuals may have done similar things in unusual and desperate situations, for which they might well have been awarded a (probably posthumous) decoration. {The poster formerly known as as 87.812.230.195} 94.1.170.37 (talk) 13:53, 20 May 2025 (UTC)[reply]

An unfortunate 'lol' at your 'probably posthumously' there. —Fortuna, imperatrix 14:25, 20 May 2025 (UTC)[reply]

It depends what he had for breakfast. —Fortuna, imperatrix 14:26, 20 May 2025 (UTC)[reply]