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January 14

Healing during pregnancy

Does pregnancy improve (or, on the other hand, hinder) the healing of pre-existing physical injuries of the mom-to-be? (Not medical advice, just curious!) 2601:646:8A81:6070:BCB8:B52F:333C:E35F (talk) 14:28, 14 January 2022 (UTC)[reply]

Susceptibility and severity of infections in pregnancy may be of interest.-gadfium 23:03, 14 January 2022 (UTC)[reply]

January 15

Limbic brain differences by sex

I know there’s a lot of debate between whether male and female brains are actually different or whether there’s more difference within sexes but is there a consensus within the scientific community? Or is it an unknown? 2A02:C7F:EA3E:8000:A148:49C0:24BF:F257 (talk) 10:18, 15 January 2022 (UTC)[reply]

The further to one side of the distribution the more likely the human is to feel male or female (which has nothing to do with their sex). I bet you could bet what gender someone from the outer 50% (could be much more) of humans identifies with with no information besides modern scans of alleged brain differences and get it wrong far less than guessing from sex but 2022 tech being able to read some aspects of some humans like a book offends some people. Especially one end of the feely/thinky, metaphysical/physical, humanities people/STEM people or non-woke/wokest spectrum. Would seem dehumanizing to actually do this behind their back though (with or without betting), you'd need full consent in advance to pass the science ethics board anyway which would add sampling error to this kind of paper (if any exist). Sagittarian Milky Way (talk) 15:53, 15 January 2022 (UTC)[reply]

There seems to be consensus that adult men have, on average, larger brains than adult women (see brain size), so that's one "difference". However, as that article discusses, linking that to intelligence is controversial. Mike Turnbull (talk) 17:14, 15 January 2022 (UTC)[reply]

Wouldn't you need more brain to have a larger body with the same density of pain, heat, touch, etc. sensors? I recall that Neanderthals had slightly larger braincase volumes than modern humans. Sagittarian Milky Way (talk) 18:21, 15 January 2022 (UTC)[reply]

Compared to women, men have excess brain capacity. Women use their brains to solve problems. Men use the excess capacity to create problems. :) --Lambiam 21:56, 15 January 2022 (UTC)[reply]

Male or female? Brains are intersex. Alansplodge (talk) 23:18, 15 January 2022 (UTC)[reply]

Are there any timers exist on historic cameras?

I am referring to this picture. How Frances Benjamin Johnston took her own photograph i.e self portrait in 1890s? Rizosome (talk) 15:53, 15 January 2022 (UTC)[reply]

Well before the IP user reverted himself there was a link to History of the Selfie. There you'll see that Kodak Brownies of the 1890s had timers. One other option was to hide the bulb tube that photographers of the time used. Martin of Sheffield (talk) 16:26, 15 January 2022 (UTC)[reply]

The availability of self-timers in the late 1880s allowed for an ease for creating self-portraits, since it gave five to ten seconds for the subject to position themselves in the shot. The launch of the portable Kodak Brownie Box camera in 1900 led to self-portraiture becoming a widespread technique.

Backer, Emma (17 September 2016). "History Of The Selfie: A Photo Phenomenon". Culture Trip. ----2603:6081:1C00:1187:3C0B:A7B2:2DD7:ED6B (talk) 16:31, 15 January 2022 (UTC)[reply]

Oops, yes, you're correct. Martin of Sheffield (talk) 16:38, 15 January 2022 (UTC)[reply]

Please update our self timer article...it's pretty poor shape. DMacks (talk) 23:00, 15 January 2022 (UTC)[reply]

An example of an 1890 shutter timer is here. Alansplodge (talk) 23:32, 15 January 2022 (UTC)[reply]

Please explain "hide the bulb tube". —Tamfang (talk) 01:41, 18 January 2022 (UTC)[reply]

One form of remote shutter release uses a rubber ball or "bulb" (yep, that's how the "B" setting got its name) on the end of a thin tube to actuate the release. Martin of Sheffield (talk) 08:55, 18 January 2022 (UTC)[reply]

I got an answer from here: An example of an 1890 shutter timer is here. Rizosome (talk) 07:53, 16 January 2022 (UTC)[reply]

Resolved

January 17

Sample and hold

From here: The original signal is retrievable from a sequence of samples, up to the Nyquist limit, by passing the sequence of samples through a type of low pass filter called a reconstruction filter.

What's the purpose of "retrieving the signal back" after sampling process? Is it referring to demodulation? Rizosome (talk) 00:36, 17 January 2022 (UTC)[reply]

For audio playback etc. Funny terminology. Greglocock (talk) 01:31, 17 January 2022 (UTC)[reply]

I've changed the wording in the article to "The original signal can be reconstructed from a sequence of samples, ...". --Lambiam 09:22, 17 January 2022 (UTC)[reply]

I got clear idea from this line: For audio playback. Rizosome (talk) 12:23, 18 January 2022 (UTC) [reply]

Resolved

Transhumanism

Hello,

thank you to the volonteers

I'm stressed, may I know the informations about Vitrifixation, please ? 37.164.32.245 (talk) 04:36, 17 January 2022 (UTC)[reply]

What are you talking about? --←Baseball Bugs ^{What's up, Doc?} carrots→ 05:12, 17 January 2022 (UTC)[reply]

Paying a company a butt ton of money to glassify your corpse as fast as possible after death and store you in Arizona in the hope that you'll wake up in a 21-year old body that cannot age or at least get to relive the nursing home till some aspect of aging they can't cure kills you again. For a mini-butt ton of money they can freeze just your head but you have to hope the future can recapitate too. Sagittarian Milky Way (talk) 06:51, 17 January 2022 (UTC)[reply]

perhaps we need a way of flagging questions as "you can google weird shit/nonsense just as well as we can"Greglocock (talk) 09:06, 17 January 2022 (UTC)[reply]

Or you could even look up Vitrification in cryopreservation in Wikipedia.--Shantavira|^{feed me} 09:29, 17 January 2022 (UTC)[reply]

Less weirdly, the OP might be asking about the method of embryo cryopreservation; see What is the vitrification technique?. But some clarification required. Alansplodge (talk) 13:28, 17 January 2022 (UTC)[reply]

The heading Transhumanism makes this is not about standard applications of cryopreservation techniques, but about an application to human brains – designated with the neologism vitrifixation – to preserve them until ways have been found to upload their information content to the cloud.^[1] Apart from the minor detail that the process involves killing the customers, there is no guarantee that it will actually preserve that content in a potentially interpretable way. There is not even a glimmer of light on the technicological horizon of a method that might hold a promise for retrieving the content, so the frozen brains may need to be kept in uninterrupted cold storage for centuries or millenia. --Lambiam 20:56, 17 January 2022 (UTC)[reply]

I stand corrected, Alansplodge (talk) 22:46, 17 January 2022 (UTC)[reply]

Reminds me of that thing where they bleed a real corpse, add an equal volume of some transparent liquid, freeze it, immobilize it to a blue floor with foot glue and photoshopped-out vises or something and take thousands of pictures. First the nude guy seen from the top, then they polish his head a little, take a photo, shave a bit more and repeat the process till just a few pieces of foot skin are left. Then let the anatomy-curious public browse all the slices online. If the guy cared then the ice shavings that the vacuum cleaner or broom or whatever cleaned after each slice are carefully collected into a 70 kilogram pile so they can be melted and cremated. Sagittarian Milky Way (talk) 00:31, 18 January 2022 (UTC)[reply]

What percentage of wild budgerigar chicks are born blue and white?

The genetic mutation that causes a budgerigar to have blue and white plumage is a simple and common recessive gene that prevents production of yellow psittacofulvin pigments (blue + yellow = green), and as far as I'm aware, if you were to take some budgies from the wild and breed them in an aviary, it wouldn't take long before some of the chicks emerged with blue feathers, instead of green. The reason you don't see many of them in flocks of wild budgies being that a blue budgie is a more obvious target for predators than a green one, so they get picked off early, or the other budgies chase them from the flock because they realize that a blue bird in the flock draws negative attention to the flock.

Has there ever been a study into the prevalence of blue budgerigars, at hatching? I'd quite like to add that info somewhere... --Iloveparrots (talk) 18:32, 17 January 2022 (UTC)[reply]

I'll bet the answer is, we don't know. Doing such a thing in the wild is a great way to fail to get your PhD. See Polly Wants a Genome: The Lack of Genetic Testing for Pet Parrot Species. Also, there is a lot of info, with some links at the bottom, at Budgerigar colour genetics, which makes it pretty clear that the Dutch run this particular show. Your best bet is to ask some of them. Abductive (reasoning) 10:54, 18 January 2022 (UTC)[reply]

Hot air

Since "hot air rises", how come the temperature at higher elevations are colder than at lower elevations? It probably has to do with less dense air, but doesn't that mean that more of the Sun's rays reach the surface? 2603:6081:1C00:1187:D94:75F0:870E:13A2 (talk) 20:19, 17 January 2022 (UTC)[reply]

Please, see lapse rate. Ruslik_Zero 20:27, 17 January 2022 (UTC)[reply]

That article mostly explains how. As for why, the best that I could glean is that energy becomes dispersed as the air expands (becoming less dense). Is that the gist, or am I missing something? 2603:6081:1C00:1187:D94:75F0:870E:13A2 (talk) 02:01, 18 January 2022 (UTC)[reply]

Hot air rises, but it's more accurate to say that air with a higher specific entropy rises. At the same pressure, higher specific entropy means higher temperature, but lower pressure also leads to higher specific entropy. As the air rises, the pressure drops, causing the air to expand adiabatically. The air does work in its surroundings (pushing air away), causing it to loose energy and cool down, but the specific entropy stays the same. This adiabatic cooling explains why the air higher up is colder, and as long as this cooling with altitude isn't faster than the cooling of a bubble of air rising, then rising air will not equalise the temperature. In other words, an atmosphere with the warm air at the bottom is stable as long as the air with higher specific entropy is at the top. PiusImpavidus (talk) 10:33, 18 January 2022 (UTC)[reply]

To add to the above, very excellent answers, the idea that "hot air rises" is broadly true, but that doesn't mean it stays hot as it rises. In a sufficiently small, relatively closed system, with a localized heat source, you will get convection currents as warm air rises and cool air sinks, and you can measure and track such movement of air, especially where such a system has a relatively uniform air pressure throughout. In other words, it works fine when describing say, your house. However, for any system as large and complex as the entire atmosphere of the earth, you aren't going to see such a temperature gradient. The above descriptions of adiabatic cooling and specific entropy are very apt here. --Jayron 32 17:19, 18 January 2022 (UTC)[reply]

January 18

Omicron vs. common cold

Is there data comparing the infectiousness of omicron covid against the common cold? What are the data I should be searching for aside from R_0, vaccine effectiveness and country prevalence statistics? I'm trying to make a Bayesian estimate, assuming I would experience omicron and cold the same way, what would be the likelihood that a given disease I experienced was omicron. 31.217.7.231 (talk) 16:25, 18 January 2022 (UTC)[reply]

This is difficult to answer as there is no such thing as the "common cold." What we call the "common cold" can be any of 200+ different viruses, and by different, I do not mean different strains. I mean different viruses that can differ from each other as much as we (humans) differ from a banana. --OuroborosCobra (talk) 16:39, 18 January 2022 (UTC)[reply]

As noted above, and as can be seen from the article Common cold, the term is not really a medically rigorous term. It generally means any viral upper respiratory infection (inflammation of the mucosa of the nose, sinuses, larynx, etc.) and while there have been over 200 different viruses associated with colds, there are likely many many more, pretty much any idiopathic infection that meets the basic symptoms of the common cold is called "the common cold". Making any broad statements about infection rates, duration, virulence, transmissibility, etc. of such a thing is basically impossible. --Jayron 32 17:12, 18 January 2022 (UTC)[reply]

It is meaningful to ask about the prevalence of symptoms, not due to COVID-19, that one would have self-diagnosed as a case of the common cold in the pre-COVID-19 era. Most adults used to have such symptoms say twice a year, mostly in the colder season (at least, outside of the tropics), lasting typically for one or two weeks. So with an onset in winter season, I'd estimate the prevalence of new cases attributable to of the common cold for an adult at somewhat over 2/365, somewhere in the ballpark between 0.5% and 1%, and of any ongoing cases at 4% to 8%. However, the same measures that reduce R_e for COVID-19 also reduce it for the transmission of common-cold viruses, so these numbers are useless for making a Bayesian estimate. --Lambiam 18:01, 18 January 2022 (UTC) [Added clause "not due to COVID-19". --Lambiam 10:23, 19 January 2022 (UTC)][reply]

How far does SETI institute broadcasts?

How far do they go?

Is it only inside the milky way galaxy, is it going a bit outside it?

Thanks, 79.176.222.75 (talk) 23:55, 18 January 2022 (UTC)[reply]

I believe the first Active SETI broadcast was in 1962. So the signal has reached less than 60 lightyears, and is targeted at a specific nearby star in our Galaxy.

There haven't been any Active SETI transmitions targeted outside the galaxy. It'd be pointless. We don't have any transmitters that would realistically reach that far, and even if we did, the signal would take 2.5 Million years to arrive. Humanity would probably be extinct by the time they got our message.

But none of that answers your exact question. I can't find a source that exactly says this, but I'm pretty sure the SETI Institute itself has never broadcast a signal. They concern themselves with listening. The broadcasts were made by other groups. ApLundell (talk) 00:14, 19 January 2022 (UTC)[reply]

That's almost certainly correct. The SETI Institute - that is to say, these people - a non-profit research organization, located in the Silicon Valley - "The SETI Institute" - (and to be circumspect, there exist other individuals and organizations who also conduct scientific research relating to the topic of SETI) - but The SETI Institute does not (currently) directly fund or operate transmitters. The folks who hang out at SETI, or are directly employed by the Institute, frequently have multiple institutional affiliations. (After all, it's kind of hard to earn rent-money while you're out looking for space-aliens - not impossible, but merely improbable). Transmissions and transmitters do exist, and could indirectly be affiliated with a person who has an affiliation with ... and so on, ad infinitum, - but the institute itself is not presently directly paying for or operating any large "Active SETI" project. Notable examples of "active" transmissions, for the express purpose of intentionally sending a signal only-for-the-purpose-of-SETI... are actually quite rare. Like so many other things we find in space science - who's gonna pay for it? Rather, it's much more common to find "SETI" (the concept) as an inspirational tag-along that rides in the backseat of a project that satisfies a clearly different scientific objective. And for this reason, it's very common to find "SETI" (the Institute) as a partner, affiliate, or "not-actually-affiliated-in-any-documented-fashion-because-the-scandal-it-might-cause-could-crush-the-public-support"). But if you hang out in Silicon Valley, you'll find SETI is conveniently located only a short lunch-break walk away from many other places that one may draw a paycheck while building giant radios and supercomputers.

Here's a review of what SETI Institute is actively doing right now - the Q3 2021 Activity Report. In addition to over 50 peer-reviewed scientific publications, several Mission Highlights include collaborations with other institutions to design and scope scientific instruments on future spacecrafts and ground stations.

Nimur (talk) 17:32, 19 January 2022 (UTC)[reply]

Or - tackling this question from a different approach: the question of how far the broadcasts go is actually a great SETI question. If we put a finer technical point on it - how do we pose the question - and myself, being a "Signal Processing" kind of person, would look at it this way. Everything you do - even just sitting around being not-absolute-zero - causes photon emissions. If we build a big antenna that absorbs photons, how can we know whether any particular photon that we receive actually came from you? This is a pretty subtle question of physics and statistics, which is actually what SETI is entirely about! We might start putting some caveats: it's pretty challenging to know anything when we receive one single photon. In fact, we can't even know for sure whether we actually received one or zero photons... - so the reception of the minimum amount of physically-possible signal is not, itself, actually "proof" of any signal at all!

Thus is born the discipline of statistical signal processing; or, stated a bit informally, how do we build machinery so that we can yield the highest statistical confidence for any query we wish to pose about a particular physical process? I mean, the rat-hole that I personally like to chase down is how the mathematical machinery of error correction codes interplay with the particular physical processes affecting our machinery: there are ways for us to select "better" codings for signals if we expect them to propagate as electromagnetic waves, and further nuances if we expect those waves to travel through the unique environment of interstellar space, and so on, and so on,...

Technically we can build a wave that propagates from here to the end of the universe - traveling at the speed of light. But the farther it goes, the fewer photons we expect to find traveling in any particular direction. What exactly happens when the expectation value drops below one photon - which is the minimum quantized amount of energy that can exist? I think there's some spooky answers that depend entirely on whether anything receives that signal, and whether this prevents somebody else from receiving the same signal on the other side of the universe. After all, there's only one photon, ... right? ... right?

Somehow, deeply and profoundly, this weird question links back to the earlier weird question - you really honestly can't know if you've received zero or one photons. If that - by inductive extension to every-number-larger-than-one - doesn't lead you in to a bit of a nihilistic melancholy, you're probably not thinking hard enough about it.

Nimur (talk) 17:44, 19 January 2022 (UTC)[reply]

In theory, across the entire universe. In practice, inverse square decay and absorption will diminish the signal to a point where it is in practical terms undetectable. Where that point is depends on which broadcast (how much power they used), and what the sensitivity of the hypothetical detection equipment is. Here's what SETI say. The current absolute limit is a 100 light years or so, given the speed of light. Ballistic missile radar signals have actually been more powerful in general, so would actually probably be more likely to be detected (dependent on wavelength). I'm surprised our article on Active SETI doesn't mention this. Fgf10 (talk) 00:17, 19 January 2022 (UTC)[reply]

January 19

Electric hobs

Domestic electric hotplates used to usually have coiled elements, like those in the first picture. Nowadays they have solid plates like those in the second. In my experience the older type are quicker to both heat up and to cool down, allowing better control of whatever it is one is cooking. Why the change? Thanks, DuncanHill (talk) 02:05, 19 January 2022 (UTC)[reply]

Cleaning? Sagittarian Milky Way (talk) 02:29, 19 January 2022 (UTC)[reply]

I'll second that. I remember as a student a lot of rented accomodation had that type of cooker, and under the elements was a difficult to get to place with the charred remains of many years of students' cooking -- Q Chris (talk) 10:37, 19 January 2022 (UTC)[reply]

Induction cooking manya (talk) 07:33, 19 January 2022 (UTC)[reply]

No it's not. Bazza (talk) 11:20, 19 January 2022 (UTC)[reply]

I would not even call the second one "modern". I had to replace my oven/hotplate unit two years ago and all electric options in the store had a vitroceramic (flat) surface rather than apparent metal. I suppose the metal-only design is less expensive to produce and low-end appliances might still do that, but at least where I looked (France, near Paris, multiple house appliances / electronics stores) the vitroceramic design has become standard. Vitroceramic is easier to clean but I suspect the real reason is design. Tigraan^{Click here for my talk page ("private" contact)} 11:47, 19 January 2022 (UTC)[reply]

They're still on sale: see here. Martin of Sheffield (talk) 12:06, 19 January 2022 (UTC)[reply]

Ceramic hobs are rather out of my price range. DuncanHill (talk) 02:16, 20 January 2022 (UTC)[reply]

I'm not sure I'm prepared to grant the premise of the question. The choice of exposed- versus sealed-coil electric elements seems to be one of style and regional preference, rather than a distinction of 'old' versus 'new'. For example, have a look at the products offered by a major U.S. retailer. It's apparent that exposed-coil elements are the preferred - possibly the only - option for a raised resistance element. (Though, as Tigraan notes, vitroceramic and induction cooktops are becoming de rigeur.)

The enclosed elements have the benefit of being somewhat easier to keep clean, as food and liquids cannot drop into the recessed 'pit' beneath them. On the other hand, exposed elements would be more 'responsive'--able to heat and cool more rapidly.

I can't say why the preference would seem to be different on one side of the Atlantic versus the other, but I note that Google Image searches for "electric hob" find almost exclusively enclosed elements, whereas "electric stove" or "electric range" brings a mix that leans much more toward exposed elements. TenOfAllTrades(talk) 14:31, 19 January 2022 (UTC)[reply]

Would you care to check your URL? I get "Access Denied You don't have permission to access "http://www.homedepot.com/b/Appliances-Ranges-Electric-Ranges-Single-Oven-Electric-Ranges/4/N-5yc1vZc3q6Z1z0jzgl/Ntk-EnrichedProductInfo/Ntt-electric%2Bstove?" on this server. Reference #18.17ce7a5c.1642603684.28522a73". I'm not sure it is regional. Coiled element hobs seem to be the cheapest, then solid hobs, then the exotics (ceramic, induction). Martin of Sheffield (talk) 14:50, 19 January 2022 (UTC)[reply]

I can't comment on the function of the URL; it still works fine for me (Google Chrome, Windows 10, and still works if incognito). Here's a simpler one that seems to be essentially the same result: https://www.homedepot.com/s/electric%2520stove. TenOfAllTrades(talk) 19:45, 19 January 2022 (UTC)[reply]

Nope. Perhaps "homedepot" don't want to talk to anyone outside your country? Is that the USA? Martin of Sheffield (talk) 20:12, 19 January 2022 (UTC)[reply]

Home Depot isn't a random website, it and competitor Lowe's are the USA's duopoly of house stuff big box "shops". Like other US big box stores they're usually an ocean of parking spaces at a roughly box-shaped building about 0.1 miles wide and having only one very tall storey (maybe cause some of the less New York City-like parts of USA have a significant population percentage that would get claustrophobic otherwise?). If you have enough F-350/450/3500 trucks (common US cars, like a big SUV with an 8 foot roofless boot) you could probably get everything you need to turn an empty field into an average fully rentable+furnished house in one unannounced shopping trip. I don't know if they have enough but I know that they rent the public pickup trucks too. Maybe even bulldozers. Not sure on that one. But if they have no shops in England and few website viewers would pay the huge shipping cost (you can get electric stoves in England after all, with the right plug, even the close part of Alaska costs extra) then they may not want you using their bandwidth. Sagittarian Milky Way (talk) 01:34, 20 January 2022 (UTC)[reply]

The Home Depot links don't work for me either. DuncanHill (talk) 02:13, 20 January 2022 (UTC)[reply]

Doesn't work for me either. Possible that they don't ship to Europe, can't be bothered to conform to GDPR and so block all non-US users. Rmvandijk (talk) 11:55, 20 January 2022 (UTC)[reply]

Apparently the UK is still under GDPR, or a UK law with the same effect in practice, if someone far from both EU and anywhere they sell to can access then your promising GDPR hypothesis is very likely true. Sagittarian Milky Way (talk) 15:23, 20 January 2022 (UTC)[reply]

The German article tells me that the solid cast-iron hobs became predominant (in Germany or central Europe, I guess) in the 1920s, so the term "modern" really is a bit of a stretch. Personally, I think I've only ever seen the open type in the US. --Wrongfilter (talk) 18:22, 19 January 2022 (UTC)[reply]

Well as the link I posted shows, they are still on sale in the UK from a leading white good supplier. Martin of Sheffield (talk) 18:31, 19 January 2022 (UTC)[reply]

This discussion has been interesting to me largely because I had been unaware of the word hob for this item. I'd have called it a "cooktop" or a "range", or possibly even imprecisely an "oven" (referring to the whole unit, not just the top). Is "hob" the normal word in the UK? Is it colloquial? What would you call it when speaking carefully? --Trovatore (talk) 02:25, 20 January 2022 (UTC) [reply]

Yes, in the U.S., the word "hob" is pretty much unknown. I am familiar with it because I am in the kitchen countertop business. The appliance is called a "stove" in common American usage if it has a oven, or a "cooktop" if no oven is included. The formal industry term for a "stove" is a "range". In the U.S., the coil heating element is common for inexpensive, entry level stoves, but more expensive units have other types of heating elements, which are called "burners". Cullen328 (talk) 02:34, 20 January 2022 (UTC)[reply]

So "stove" is the other word I might use, sure. The house I grew up in had cooktop separate from oven rather than in a single unit, and I think I called them both the "stove".

It also sounds as though some of the participants use "hotplate" to mean cooktop (or maybe just a single burner?). To me a hotplate is a standalone single burner, generally low-powered, that allows college students to heat up soup in their dorm rooms without too much chance of burning the place down. --Trovatore (talk) 02:41, 20 January 2022 (UTC)[reply]

In the U.S., "hotplate" refers to a small, inexpensive portable appliance, not to an appliance that would be permanently installed. Cullen328 (talk) 02:44, 20 January 2022 (UTC)[reply]

Yes, that's what I meant. But it doesn't seem to be how some above are using it. --Trovatore (talk) 03:10, 20 January 2022 (UTC)[reply]

The hob is the top part of the cooker, it contains hotplates (or gas rings, sometimes called just rings, if it's a gas hob) which are the things that get hot underneath sauce- and frying-pans. There are four hotplates visible in the picture at the top of this section. The oven is the box-like part of the cooker which gets hot and is used for baking and roasting. The whole thing is a cooker, and may include a grill, in which food is cooked under radiant heat. You can have separate hobs, ovens, and grills. A stove is powered by coke, coal, or wood, and may just be a room-heater, not a cooker. A range is either a posh, modern, huge cooker, or an old-fashioned (usually coke, coal, wood, or gas powered) thing you'd find in a farmhouse or the 19th Century, and which would be used for both cooking and heating water for washing day, and which the proud housewife or the put-upon skivvy would polish with black lead. DuncanHill (talk) 03:30, 20 January 2022 (UTC)[reply]

Many NYC rentals have gas ranges and portable hotplates are good for the subset of renters who wish to avoid paying two-digits of bucks just to use a few bucks of gas. For the price of only two coils 3 people can cook every day under bright fluorescent and have a normal (non-mini) fridge and take long showers under 25 watts and watch VHS or free SDTV on 27" electron gun in the dark all evening (this was a long time ago) and use only 120 kilowatt-hours per month (one-third the New York City average). What's a white good? Sagittarian Milky Way (talk) 04:02, 20 January 2022 (UTC)[reply]

White goods (I don't think I've ever seen "white good" until today) are cookers, fridges, freezers, washing machines, tumble dryers, and the like. Wikipedia calls them major appliances. To my ears a "major appliance" sounds like something Bloodnok might have to adjust DuncanHill (talk) 05:06, 20 January 2022 (UTC)[reply]

Yay, my first guess was right. If that had been an American term a third of the country would be rubbing it in peoples' faces to try to irritate them while some of the rest would call the original a phrase of oppression as bad as the N-word. Sagittarian Milky Way (talk) 06:02, 20 January 2022 (UTC)[reply]

What's the name of this device?

I want name of this device. I think it's used to lift heavy objects. Rizosome (talk) 06:59, 19 January 2022 (UTC)[reply]

It looks like some kind of "toe jack" to me. 41.165.67.114 (talk) 08:05, 19 January 2022 (UTC)[reply]

It could be associated with the motor trade, but the base does not look substantial enough to me. The alternative is agricultural, variously known as a "cabin ratchet" or "farm jack". See cabin ratchet* or farm jack* for examples. *Found via the internet, I have had no dealings with these firms and make no recommendations. Martin of Sheffield (talk) 08:39, 19 January 2022 (UTC)[reply]

I seems that the base is meant to be bolted to the floor. Also, part of the device has been removed; is it the motor lying on the floor? The toothed structure looks to me more like a rack, meant to engage with a gear, forming a linear actuator allowing for controlled motion in either vertical direction. (A ratchet is for motion in one direction.) --Lambiam 10:06, 19 January 2022 (UTC)[reply]

I don't think the base is meant to be bolted down, that curved thing at the front looks more like a stabiliser leg. The bolt on the right may well be for another leg that is missing. I agree about the ratchet vs rack-and-pinion, but that is because it looks as though it is designed for motor operation rather than hand operation. It would be interesting to know what used to be bolted to the working face. Martin of Sheffield (talk) 10:25, 19 January 2022 (UTC)[reply]

Whatever was bolted to the exposed face must have moved the pinion (mounted in the wide vertical slit) and, unless operated by manual power, contained a motor. So I think we are looking at the backside; the load being hoisted was then at the other side. --Lambiam 22:09, 19 January 2022 (UTC)[reply]

That white stuff splashed around the bottom of it looks like it is a rock drill of some sort. If you fastened that drill lying behind it back onto the plate that slides up and down the rack, it would look a bit like this https://www.machinio.com/listings/55550554-small-portable-borehole-mining-hydraulic-hard-rock-drilling-machine-in-shanghai-china Just a Guess!!49.197.155.118 (talk) 07:29, 20 January 2022 (UTC)[reply]

The rock drill theory neatly explains the rounded recess in the foot of the device, also seen in this rock drill machine. I imagined the part on the floor was meant to be mounted vertically on the exposed plate, but did not identify it as a heavy-duty drill, which it plausibly is. --Lambiam 14:14, 20 January 2022 (UTC)[reply]

Rack-and-pinion lift? --Lambiam 10:19, 19 January 2022 (UTC)[reply]

I am satisfied with multiple answers here. Rizosome (talk) 09:11, 20 January 2022 (UTC)[reply]

Resolved

Why more (ecological) forest generally means more rain?

Please suffice an explanation aimed for non-chemists / non-meterologists.

Thanks, 79.176.222.75 (talk) 12:26, 19 January 2022 (UTC)[reply]

This article published by Yale University does a good job of explaining the role that forests play in moderating local climate; including their effect on rainfall. --Jayron 32 13:30, 19 January 2022 (UTC)[reply]

Also suitable amount of rainfall, temperature, and sunshine get you a rich ecosystem like a rain forest. It's not that a forest causes rain, it is that rain causes a forest. 85.76.87.150 (talk) 16:18, 19 January 2022 (UTC)[reply]

Actually I read that also, forests cause rains, in general, especially if there is enough forest, in a given area. I read that in the past but never got an explanation. 79.176.222.75 (talk) 17:06, 19 January 2022 (UTC)[reply]

Both are correct; it's a complex system, the climate, and while rainfall does lead to forests, forests do also cause an increase in rainfall; the article I linked has some explanations as to why. --Jayron 32 17:20, 19 January 2022 (UTC)[reply]

In addition to the transpired water mentioned in Jayron's article above, this article (reporting this paper) says that rainforests also produce their own cloud condensation nuclei. Alansplodge (talk) 21:21, 20 January 2022 (UTC)[reply]

Is there a difference between "(ecological) forest" and other forest? —Tamfang (talk) 02:07, 21 January 2022 (UTC)[reply]

I don't know but possible distinctions could be forests that can't grow there naturally without human help like a indoor, watered or fabric-shaded one and places like clear cuts, Times Square and some golf courses that were, would be or will be forest if given the chance. I know there's an ecological term for what a place "ought" to be or will end up as without human intervention. Sagittarian Milky Way (talk) 02:58, 21 January 2022 (UTC)[reply]

January 20

Weather machine

Did anyone ever actually attempt to create a device for the purposes of manipulating the weather? Once read something about how the US military looked into how the butterfly effect could be weaponized to cause weather in Russia that would lead to droughts, floods, tornadoes, etc. - some facilty in Alaska? Also that the Russians were trying to do it too, but that it didn't work and so everyone gave up on it. Probably a conspiracy theory (I enjoy reading those sometimes), but just curious. 146.200.129.104 (talk) 11:55, 20 January 2022 (UTC)[reply]

See weather modification to see various efforts to manipulate the weather, to varying levels of success. Wikipedia has an article on everything. --Jayron 32 13:18, 20 January 2022 (UTC)[reply]

For a conspiracy theory, see HAARP#Conspiracy theories. 2603:6081:1C00:1187:25B6:3B5:BCF7:4392 (talk) 14:55, 20 January 2022 (UTC)[reply]

The butterfly effect is that a butterfly wing flap on the other side of the world could literally be the difference between a hurricane or no hurricane years from now, there's no possible way humans could predict that. How do you have a years-long 24/7 video of the movements of a cow who isn't even born yet? Much less the entire world, even in caves? Sagittarian Milky Way (talk) 16:36, 20 January 2022 (UTC)[reply]

Except that the so called "butterfly effect" is not literally that a butterfly flaps its wing and it could mean the difference between a hurricane or no hurricane years from know. It is an analogy to explain how small changes in initial conditions can have large effects on outcomes of models. As stated in our article: "Of course the existence of an unknown butterfly flapping its wings has no direct bearing on weather forecasts, since it will take far too long for such a small perturbation to grow to a significant size, and we have many more immediate uncertainties to worry about. So the direct impact of this phenomenon on weather prediction is often somewhat wrong." A large initial perturbation CAN have a measurable impact, and one that is far easier to predict than a small perturbation.. --OuroborosCobra (talk) 18:35, 20 January 2022 (UTC)[reply]

The fact that I said you'd have to account for the cows and the caves and everything else in the world 24/7 shows that I knew the butterfly was just an example. Is a large initial disturbance (like nuking a hurricane I guess or maybe cloud seeding) really what scientists mean when they say the butterfly effect? I never said such tiny air disturbances could be accounted for in weather forecasts, in fact I said it could never be. No one could possibly make a model of the atmosphere that accurate. And since the minimum air disturbance size that materially affects the weighted random number generator that is weather shrinks with longer time horizons there definitely should be a time that's far enough in the future that every tiny animal movement now will change all the weather after then (without materially changing the climate probabilities, i.e. a dinosaur or Cro-Magnon couldn't have materially changed the percent of the 2nd millennium at 52°N 0°E 1km above sea level that was rain). Sagittarian Milky Way (talk) 19:24, 20 January 2022 (UTC)[reply]

Power source for Jupiter's aurorae

Does their energy ultimately come from Jupiter's rotational energy or from its internal heat (via convective dynamos)? I've been looking for papers but none explicitly analyzes these questions. JoJo Eumerus mobile (main talk) 20:44, 20 January 2022 (UTC)[reply]

The mechanism for the Jovian aurorae is basically the same as for the terrestrial aurorae: ionization and excitation of atmospheric gases by charged particles affected by disturbances with the planet's magnetosphere. The source of these particles on Earth is primarily the solar wind; from the JADE results it is known that there is an important other source in play on Jupiter. The magnetic field forming the magnetosphere is thought to be generated by what is called an "interior dynamo", but the mechanism is poorly understood. Here are links to scholarly articles on dynamo models for Jupiter. --Lambiam 21:18, 20 January 2022 (UTC)[reply]

Agreed: These dancing lights are produced when energetic particles from the sun or other celestial bodies slam into a planet's magnetosphere — the area controlled by a world's magnetic field — and flow down its magnetic field lines to collide with molecules in its atmosphere. Jupiter's magnetic field is extremely strong — about 20,000 times more powerful than Earth's — and therefore its magnetosphere is extremely large. If that alien magnetosphere were visible in the night sky, it would cover a region several times the size of our moon. As such, Jupiter's auroras are much more powerful than Earth's, releasing hundreds of gigawatts — enough to briefly power all of human civilization. [2] Alansplodge (talk) 21:29, 20 January 2022 (UTC)[reply]

Can there be an immediate way to broadcast sound in the universe? "Bypassing relativity"?

I understand that the stars we see are actually light from stars that existed in the past (billions/trillions of years ago) and may no longer exist today, so the light is still "doing it's way" to us (even though it travels in a blazing speed).

Is there really no way to broadcast signals (light/sound) without this "slowness"? For example, is there no way for humans, at least in theory, to broadcast sound signals to other galaxies in some **immediate media**, bypassing the common situation of fast-but-slow *light speed travel*? — Preceding unsigned comment added by 79.176.222.75 (talk) 23:04, 20 January 2022 (UTC)[reply]

Maybe via tachyons, if they exist? (Otherwise, you'd have to get some unobtainium to build a transmitter, although it is rumored that gossip travels much faster than the speed of light.) Clarityfiend (talk) 23:37, 20 January 2022 (UTC)[reply]

Quoting our article Faster-than-light, oddly named, but whose topic is, specifically, faster-than-light communication:

Particles whose speed exceeds that of light (tachyons) have been hypothesized, but their existence would violate causality, and the consensus of physicists is that they do not exist, and their existence would imply time travel.

Actually, the mere assumption of the possibility of faster-than-light communication in a universe satisfying basic special relativity, regardless of the communication medium (waves, particles, telepathy, morphogenetic fields, Infinite Improbability Drive), already clashes with causality. If event S (send info) precedes event R (receive info) in some observer's frame of reference, and their separation implies FLT communication, the interval between the two events is spacelike in the Minkowski metric. This implies there is another frame of reference in which, for its observers, R precedes S: the message is received before it was sent. --Lambiam 01:00, 21 January 2022 (UTC)[reply]

That by itself is not necessarily a problem; that time is just a coordinate value you assign to the event, and it's OK in and of itself if the number is smaller. What's really a problem is if you can get a causal loop, which you can, if the faster-than-light communication conforms with relativity. We have an article: tachyonic antitelephone.

Note that there is an assumption here. What if relativity doesn't work for tachyons? Maybe there is a preferred frame of reference, but you can't tell if you just look at photons and bradyons, which is all we've ever observed. This would fit with a neo-Lorentzian interpretation of special relativity, generally disfavored in the current day, but on metaphysical rather than empirical grounds. --Trovatore (talk) 01:20, 21 January 2022 (UTC)[reply]

This reminds me of TV ads where (unlike real life) the Twin Towers roof had a microphone and giant speakers and the bald guy would say "the New York Lottery jackpot is now (number).. MILLION.. DOLLARS!" and people are shown confused by the booming sky voice's existence at ever increasing distances and very exaggerated volume dropoff slowness finally ending with it still being loud enough to understand over the roar of Niagara Falls (hundreds of miles away). I always wondered if each TV market got a local version. Sagittarian Milky Way (talk) 01:13, 21 January 2022 (UTC)[reply]

January 21

Schrödinger's cat = Checking whether a coin is fair??

Why Schrödinger's cat is treated different from coin flipping? They both have 2 possible outcomes. One is treated as though experiment, other one falls under Maths. Rizosome (talk) 03:51, 21 January 2022 (UTC)[reply]