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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)

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)

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)

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)

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

Why do you think they took real tinfoil off the market? —Tamfang (talk) 19:04, 23 May 2025 (UTC)

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)

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)

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)

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)

The report mentions that the boiler water level had dropped to 7+1⁄4 in (18 cm) below the highest point of the crown sheet (page 6). The lowest point of the water glass was 6+1⁄2 in (17 cm) above the highest point of the crown sheet (page 9) and the glasses where 6+1⁄2 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 6+3⁄4 in (17 cm) above the crown sheet top (page 11). Apparently, a witness told that the low water alarm sounded 1+1⁄2 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)

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)

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)

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)

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)

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)

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)

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)

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)

Physics and category theory

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

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)

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)

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)

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)

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)

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

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

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)

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)

Viriditas, I think it is worth noting that despite a number of competing theories and open questions about the precise planetary mechanics, the Theian Impact model remains the overwhelmingly dominant theory. A major factor contributing to stronger confirmation of any one model, in addition to those already noted by Lambiam, is the vast amount of time that elapsed since the formation of the Earth and Luna, and the resulting need to reverse-engineer the material arrangement of the solar system in the relevant far-distant epochs. As to the notion of new tools adding at least some degree of confidence to any scientific consensus, yes, that is always a possibility--to a point. In particular, quantum computing and AI can be expected to lead to some semi-near-term advancements in relevant modelling. But because we have many gaps in in requisite data to fix various of the variables relevant to the existing theories, a much stronger consensus than exists now will probably remain evasive for a long time. As to whether we have a confirmation of a moon in formation outside the solar system, the answer (I believe) is no. Remember that it is actually within just a couple of decades that we could even begin to validate the existence of exoplanets, and we continue to do so through indirect observation of stellar bodies. Being able to confirm fine details of the mechanics of the formation of an exomoon is well outside the scope of our current celestial observation capabilities--indeed, we're not even to the stage of a firm confirmation of a single exomoon's existence. SnowRise ^{let's rap} 03:20, 22 May 2025 (UTC)

Gerotranscendence

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

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)

(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)

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)

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

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

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

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)

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)

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)

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)

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)

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)

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

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)

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

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)

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)

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)

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)

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)

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

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)

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)

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)

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)

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

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)

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

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)

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)

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)

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)

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

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)

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)

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)

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

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)

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)

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

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".

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

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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)

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)

Of course, but what about two measuring instruments that accelerate relative to each other? Will they measure the same speed of light, according to each set of quotes mentioned in my original post? HOTmag (talk) 00:04, 23 May 2025 (UTC)

In an inertial frame of reference you can make a local clock by observing a light package bouncing between two parallel motionless mirrors, which can serve as the basis for setting up a coordinate system. The problem is really in how to define a non-local coordinate system from a non-inertial frame of reference. You can write in your lab notes, "Event E was observed at position (x₁, y₁, z₁) at time t₁." How did you measure the values of these non-local coordinates? Will they still be in any sense meaningful at time t₂? Is the space point (x₁, y₁, z₁) still "where it was" at time t₁?  ​‑‑Lambiam 16:31, 23 May 2025 (UTC)

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)

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

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)

Wouldn't the g-force experienced depend on the weight of the soldier? Alien878 (talk) 08:12, 21 May 2025 (UTC)

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)

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

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

I'm surprised nobody mentioned the North Hollywood shootout. Abductive (reasoning) 14:55, 20 May 2025 (UTC)

One Mr Edward Kelly was an early pioneer of armour vs firearms tactics, although he didn't use or face automatic weapons or machine guns. {The poster formerly known as 87.81.230.195} 94.1.170.37 (talk) 15:41, 20 May 2025 (UTC)

Curiously, Heavy gun is a redirect to Heavy machine gun, but most occurrences of "heavy gun" appear to refer to crew-served artillery. -- Verbarson  ^talk_edits 16:42, 20 May 2025 (UTC)

An example from the First World War was the Italian Compagnie della morte of late 1915, who were tasked with cutting enemy barbed wire with pliers and wore medieval-style armour.

See this image. Not terribly successful, one Italian officer wrote; "Before going out to attack, they send men with pliers to remove the wires from the enemy fences. Ordinarily, neither pliers nor men return". Alansplodge (talk) 17:34, 20 May 2025 (UTC)

Looking at the history, that redirect is positively antediluvian. If you're confident there's a better target (er, pun unintended), I'd say go for it -- Avocado (talk) 16:55, 23 May 2025 (UTC)

I've pointed it to Large-calibre artillery. I have insufficient knowledge to be sure it's the best, but it is definitely better than before. -- Verbarson  ^talk_edits 20:43, 23 May 2025 (UTC)

The short answer, as people have indicated above is no. However, the video-game/media trope has connections with real-life tactics such as Shock troops and Infantry weapons officer. The problem is the trade-off between power and speed. Eluchil404 (talk) 21:36, 20 May 2025 (UTC)

Contaminated oil

If oil which has been contaminated with seawater is used to fuel an oil-burning steam locomotive (assuming that the temperature is above freezing, so that ice crystal formation is not an issue), is there likely to be an immediate (= within no more than a few hours) failure of the burners in the firebox? Or would the engine be OK for a few days while the maintenance department (or the logistics department, or the fueling department if there is one) gets the problem sorted out? 2601:646:8082:BA0:2C:610F:A84:CB25 (talk) 22:32, 20 May 2025 (UTC)

The burners in steam locomotive fireboxes were made of iron or steel. The salt in seawater causes them to corrode through a process called oxidation. But this is not the end of the world.  If caught early, a technician in the maintenance department should be able to resolve the problem without causing significant long-term damage. Stanleykswong (talk) 06:49, 21 May 2025 (UTC)

The oxidation process is also known as rusting.  ​‑‑Lambiam 07:43, 21 May 2025 (UTC)

Right, I'm aware of corrosion -- what I wanted to know, though, is whether this could cause more immediate problems, e.g. through phase separation causing blockages in the burners and/or fuel lines (analogously to what would happen to a diesel in this scenario)? 2601:646:8082:BA0:95F1:4DFA:95FD:527C (talk) 11:15, 21 May 2025 (UTC)

Even under normal operation, burner and fuel line blockage is inevitable. There is no doubt that the salt in seawater increases the risk. Stanleykswong (talk) 11:23, 21 May 2025 (UTC)

Per GWR oil burning steam locomotives, the oil was heated by steam to make it flow, then atomised by steam in the burner to allow rapid combustion. The atomisers had to be removed and cleaned daily. With that level of interaction with steam, and daily maintenance, I doubt that salt water contamination would cause noticeable blockages or further degradation. -- Verbarson  ^talk_edits 17:31, 21 May 2025 (UTC)

So here's what I really wanted to know: in "Thomas to the Rescue" (where all the diesels break down due to seawater contamination of their fuel and Thomas has to bring them fresh fuel from the depot), had Victor and Timothy (the only two oil-burning steamies on Sodor) been on the NWR at the time (they weren't introduced until much later), would they have broken down as well? (Yes, I'm aware that diesels and oil burner (engine)s use fuel with different volatility parameters, but let's ignore that point in this case!) 2601:646:8082:BA0:95F1:4DFA:95FD:527C (talk) 22:12, 21 May 2025 (UTC)

Steam is less corrosive than salt water. Salt water contains large amounts of chlorides, which are more corrosive to metals due to electrochemical reactions, especially at high temperatures and pressures.

There is no mention in the GWR archives of what atomizer design they used. Of course, for a large engine, using steam sounds like it would make more sense than using air. Also, they did not mention whether the water was pre-treated before use. There is no mention in the GWR archives of what atomizer design they used. Of course, for a large engine, using steam sounds like it would make more sense than using air.

Also, they did not mention whether the water was pre-treated before use. In the electronics industry, deionized water is used to clean printed circuit boards, and it is possible that they used a similar process (maybe a more primitive approach) to remove mineral ions from the water. Or, did they use steam injection or other method to physically remove dissolved oxygen from the water before using it? Stanleykswong (talk) 06:52, 22 May 2025 (UTC)

OK, never mind the corrosion (it takes weeks for corrosion to start causing trouble) -- what about more immediate failure modes, like an atomizer blockage or a chemistry-related combustion upset of some sort? 2601:646:8082:BA0:95F1:4DFA:95FD:527C (talk) 21:30, 22 May 2025 (UTC)

This depends on the design of the atomizer.  If it is a pressure atomizer, the design is relatively simple. It is actually an oil nozzle, very similar to a sprayer for gardening. If corrosion causes the atomizer to become clogged, simply removing and cleaning the nozzle may resolve the problem. Stanleykswong (talk) 21:55, 22 May 2025 (UTC)

As stated in the GWR article (and cited to Griffiths 1987, available here, pp.123-124), the GWR ended up with Laidlaw-Drew atomisers, possibly like this.

The same book, p.69, confirms that the GWR had long used water treatment for boiler water, and though was directed to extending boiler life, it would probably have benefitted the atomisers by reducing particulates and dissolved minerals.

Here is a detailed diagram. -- Verbarson  ^talk_edits 22:03, 22 May 2025 (UTC)

Right, but in this case we're talking about water dissolved in the fuel oil as received by the railroad, not water in the form of steam injected into the nozzles to help atomize the oil (which is normal, and which uses purified water from the boiler, as you correctly pointed out). In other words, a scenario similar to that in "Thomas to the Rescue"! 2601:646:8082:BA0:95F1:4DFA:95FD:527C (talk) 01:48, 23 May 2025 (UTC)

You are asking what would happen in an already fictional situation if the writer had written it differently. The fact is, that anything that would suit the story could happen, up to and including Thomas turning green, the er... physically-enhanced Controller resigning, and pigs flying. If you want to ask a science question, you should specify the grade of oil, the concentration of seawater, and the design of the atomiser and associated pipework. Anyway, I was taught that oil and water don't mix. Wouldn't the seawater separate out and float on top? -- Verbarson  ^talk_edits 17:16, 23 May 2025 (UTC)

To be fair, the author Wilbert Awdry was knowlegeable (for an amateur) about railways and, outside of the fantastic elements of sapient locomotives and rolling stock, attempted to be as realistic as possible in his plots, many of which were based on or inspired by actual incidents on real-life UK railways.

That said, the OP's deliberate ignoring of the fact that diesel fuel and locomotive fuel oil are two completely different things combusted in completely different equipment, and would not have suffered from the same contamination (unless by two acts of sabotage), in my view rather negates any point of discussing the minutiae of oil-burning locomotives. And as others have explained, seawater-contaminated fuel oil might have caused minor corrosion of parts, but would not have caused a quick breakdown, as seawater in diesel fuel would.

[Edited to add] Note that due to the constant physical agitation endured by a running locomotive, the seawater and fuel oil would, I suggest, probably remain in an emulsified mix rather than settling out. {The poster formerly known as 87.81.230.195} 90.193.154.147 (talk) 22:03, 23 May 2025 (UTC)

References

Mostly it would, but a small amount (maybe not even all that small, it could range as high as a few parts per thousand) would remain in the oil as an emulsion (had the separation been complete, there would have been no need for desalting/dewatering the oil at refineries, but the fact is, all of them have desalters installed upstream of the atmospheric distillation unit) -- and also, depending on the grade of oil, the water could actually sink to the bottom upon separation (which could lead to it physically displacing the oil from the fuel line, causing immediate burner flameout regardless of the design of the burner), could it not? Also, this is a science question -- I am asking what would happen in a real-life scenario similar to the fictional one which the Reverend had come up with (don't forget, many of his Thomas stories were actually based on real-life incidents he had personally seen or heard about, including one in which he had personally given his train the highball too early by mistake and stranded his passengers)! As for your question re. fuel specs, just for the sake of the argument, let's go with, say, #4 fuel oil and a seawater concentration of, say, 2000 ppm (which, had it been in diesel fuel instead, would be plenty high enough to cause immediate failure of any diesel engine unfortunate enough to use that batch of fuel, or at least that's what my sources tell me!) 2601:646:8082:BA0:95F1:4DFA:95FD:527C (talk) 21:53, 23 May 2025 (UTC)

May 23

DMEM (explain the joke?)

https: //mander.xyz/pictrs/image/12b51d24-e090-4a6b-9cf7-b6ec674d99c3.jpeg What is this stuff? Thanks. 2601:644:8581:75B0:A690:D665:179B:79F0 (talk) 12:00, 23 May 2025 (UTC)

Eagle's minimal essential medium. Not sure about the joke though. I assume it's a single node in some gigantic meme-based causal network i.e. you had to be there. Sean.hoyland (talk) 15:24, 23 May 2025 (UTC)

The image is a cut-out of a stock photo. The fridge itself is a household fridge, not a typical lab fridge, even though the image is used by a provider of refrigerators that comply with laboratory standards. The posting (of May 19) is on Facebook here. I don't get the joke, but many of the jokes on the user's page are super nerdy, supposed to appeal to people working in biochemistry labs.  ​‑‑Lambiam 16:00, 23 May 2025 (UTC)

Thanks all, I suspect none of us are really missing much. 2601:644:8581:75B0:A690:D665:179B:79F0 (talk) 17:39, 23 May 2025 (UTC)

size vs age of universe, name of discrepancy

The universe is supposed to be 13.8 billion years old, while the observable part has estimated radius 90 billion light years. The discrepancy is explained by the expansion of space, particularly during the inflationary period. I'm not asking about the explanation right now. I'm just wondering whether the apparent contradiction has a name, like "so-and-so's paradox". I couldn't find anything about it by clicking in some of the relevant articles. Thanks. 2601:644:8581:75B0:A690:D665:179B:79F0 (talk) 17:38, 23 May 2025 (UTC)

You can read comoving and proper distances. Ruslik_Zero 20:35, 23 May 2025 (UTC)