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I lost interest in extrasensory perceptions long ago also but what if there is a connection between the two phenomena in the title? Thanks, [[User:AboutFace 22|AboutFace 22]] ([[User talk:AboutFace 22|talk]]) 16:54, 23 October 2019 (UTC)
I lost interest in extrasensory perceptions long ago also but what if there is a connection between the two phenomena in the title? Thanks, [[User:AboutFace 22|AboutFace 22]] ([[User talk:AboutFace 22|talk]]) 16:54, 23 October 2019 (UTC)
:NO. Good god no. Extrasensory perception, in the sense of "magical powers to sense things no one else can" is unmitigated bullshit. Physicists even have a derogatory name for the "magic can be explained by quantum!" and it's [[quantum woo]]. Magical powers are not caused by quantum effects. Just no. --[[User:Jayron32|<span style="color:#009">Jayron</span>]][[User talk:Jayron32|<b style="color:#090">''32''</b>]] 17:46, 23 October 2019 (UTC)
:NO. Good god no. Extrasensory perception, in the sense of "magical powers to sense things no one else can" is unmitigated bullshit. Physicists even have a derogatory name for the "magic can be explained by quantum!" and it's [[quantum woo]]. Magical powers are not caused by quantum effects. Just no. --[[User:Jayron32|<span style="color:#009">Jayron</span>]][[User talk:Jayron32|<b style="color:#090">''32''</b>]] 17:46, 23 October 2019 (UTC)
::See our Articles [[Extrasensory perception]] and [[Quantum entanglement]] for an overview. I am not a professional in this but id guess the [[Hidden-variable theory]] seems the closest answer for the moment. --[[User:Kharon|Kharon]] ([[User talk:Kharon|talk]]) 17:52, 23 October 2019 (UTC)

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October 11

October 16

Flu Jab

When getting the flu jab, there is a form that needs to be filled out. One of the questions asks, how do you feel at the moment. Hypothetically if one were to fill this in and say you were healthy but actually you already had the flu, what would the outcome be? Would you end up with pneumonia Also, what is the difference between pneumonia and simply having the winter flu? How would one tell the difference between really bad flu and pneumonia? This just a hypothetical, its not a request for medical advice. I am more curious in the science behind it. Thanks Anton 81.131.40.58 (talk) 10:53, 16 October 2019 (UTC)[reply]

See https://immunisationhandbook.health.gov.au/vaccine-preventable-diseases/influenza-flu for some government information. I will leave you to read this and figure out whether immunization is recommended when you are already sick. Graeme Bartlett (talk) 11:06, 16 October 2019 (UTC)[reply]
To the final question, pneumonia, which you linked, is an inflammatory condition of the lungs, which is caused by various infections as well as non-infectious conditions (though infection is vastly more common). Pneumonia is not itself an infection. The flu is generally experienced as an upper respiratory tract infection, well clear of the lungs themselves. Someguy1221 (talk) 11:13, 16 October 2019 (UTC)[reply]
Yes, but the influenza article says that bad cases can lead to pneumonia, so my question is, how would one known when the trasition has happened? Thanks Anton 81.131.40.58 (talk) 11:37, 16 October 2019 (UTC)[reply]
The Wikipedia article titled Pneumonia has an entire section labeled diagnosis, that should tell you how one would know when one has pneumonia. --Jayron32 12:17, 16 October 2019 (UTC)[reply]
Exactly. But just to emphasize Someguy's point, pneumonia is not what you "catch", it's what you sometimes experience depending on how what you've "caught" has progressed. You could substitute conditions like "persistent cough" or "post nasal drip" - you don't "catch" those; you "caught" the cold or flu or whatever and it has infected you successfully enough to induce those responses. It may seem like a technicality, but it's an extremely important one. Matt Deres (talk) 20:26, 16 October 2019 (UTC)[reply]
Note also per the article, bacteria are more common causative agents than viral ones in most situations, although causative agents cannot always be identified. So if you just know someone has pneumonia it's not generally wise to jump to influenza without further information. Nil Einne (talk) 07:53, 17 October 2019 (UTC)[reply]
Also, also important is the notion of secondary infection, which means that, strictly speaking, the pneumonia may not be caused directly by the influenza virus, however the flu may make one susceptible to other infections, and those OTHER infections may be what causes the pneumonia. --Jayron32 12:14, 17 October 2019 (UTC)[reply]
@ Someguy - According to the Mayo Clinic the signs and symptoms of flu are:- fever over 100.4 F (38 C), acheing muscles, chills and sweats, headache, dry, persistent cough, fatigue and weakness, nasal congestion and sore throat. That list seems a bit more than an upper respiratory tract infection and that is probably because influenza is a body-wide infection. (Anecdote warning) Having had flu 3 times in my life it is well beyond a URTI in my experience. Richard Avery (talk) 22:28, 17 October 2019 (UTC)[reply]
Hi Richard. That is a very crucial observation, but it might not mean what you think it does. Or "upper respiratory infection" might not mean what you think it does. Or maybe your statement doesn't mean what I think it does. Anyway, the cells that are infected by a virus do not necessarily coincide with the organs that develop symptoms. Because the immune response to an infection includes the release of systemic signalling molecules, the entire body can feel the effects. I'm not sure of a single article that goes over this in good detail, but I'd direct you to cytokine, chemokine, interferon, and the woefully short immune response. Someguy1221 (talk) 08:14, 18 October 2019 (UTC)[reply]
I got a flu jab a couple days ago and didn't have to fill anything out. They asked if I had any allergies to them and I said no and I had a jab 2 years ago with no noticible side effects. I didn't fill anything out that time either, iirc, and it was at a different facility. 173.228.123.207 (talk) 23:27, 17 October 2019 (UTC)[reply]
I take it "jab" is a Britishism? ←Baseball Bugs What's up, Doc? carrots→ 00:54, 18 October 2019 (UTC)[reply]
Indeed, equivalent to 'jag', which is a Scottishism. Richard Avery (talk) 07:24, 18 October 2019 (UTC)[reply]
Jab would be an injection and as far as filling out form, I assume that different countries do it differently. Anton 81.131.40.58 (talk) 15:27, 18 October 2019 (UTC)[reply]
You seem to be worrying that having the jab will make things worse. You do realise that the flu innoculation is dead and you cannot get flu from having it?[[1]] --Ykraps (talk) 18:29, 21 October 2019 (UTC)[reply]
Not a single person, not even the OP, said that. You were the first person to bring it up. It's a good thing to mention, but literally no one here mentioned anything about it before you. --Jayron32 18:32, 21 October 2019 (UTC)[reply]
The OP asked what the outcome would be if he put down that he was healthy when he wasn't. That seems an odd thing to ask if you're not worried that the inoculation will make your health issue worse.--Ykraps (talk) 19:47, 21 October 2019 (UTC)[reply]
In the States at least, it is definitely not recommended to get a flu vaccination if you're already sick. I don't really know exactly why, but it's what they always tell you. Presumably it's for some reason other than a worry that the vaccination might give you the flu. --Trovatore (talk) 20:27, 21 October 2019 (UTC)[reply]
Although you're not injected with a live virus, your immune system will attack it, and if you're already ill, you could further compromise your system. Plus (and maybe more likely), this could be kind of a disclaimer in case someone lies about being sick and then tries to sue the makers of the vaccine. ←Baseball Bugs What's up, Doc? carrots→ 22:28, 21 October 2019 (UTC)[reply]
I suppose contention for immune resources is one possibility, though I have never really heard of that. Another I can think of is that the vaccination might provoke an immune overreaction, such as a cytokine storm. But both of these are speculation; someone should be able to find out the true rationale. --Trovatore (talk) 02:25, 22 October 2019 (UTC)[reply]
I was on the right track. Here's a detailed explanation.https:// www. verywellhealth .com/ what-will-happen-if-i-get-a-flu-shot-while-im-sick-770545 ←Baseball Bugs What's up, Doc? carrots→ 03:59, 22 October 2019 (UTC)[reply]
The NHS says it's a good idea to delay the jab if you have a fever (although it doesn't say you have to) but for minor illnesses with no fever, there's no problem.[[2]] The website User:Baseball Bugs has provided recommends the same but talks about a significant fever with a temperature of over 101f. The possible outcomes are also given so the OP can extract his answer from that.--Ykraps (talk) 07:54, 22 October 2019 (UTC)[reply]

I have to say I also wondered if the OP was confused on the issue and thought of replying when I first saw this so Ykraps is not the only one.

As a point of clarification Live attenuated influenza vaccine does exist but it's a nasal spray not a jab. The risk if getting an infection from that is very low. Still as per the source from the manufacturer, such vaccines as I think with all live attenuated vaccines, are not recommended for immunocompromised patients. In fact, that vaccine isn't even recommended for those who care for severely immunocompromised patients (i.e. "boy in the bubble" type), or if they receive it they need to avoid contact for 7 days. See also the CDC [3]

As for the original question, when I first read it I had a look but could only find crappy sources like the one BB provided so didn't link to them. Looking again I found [4] which is very slightly better but it's still a blog. Although these are not great sources, they do tally with what I would expect. The primary concerns is there could be confusion over whether you are having a reaction to the vaccine as well as the possibility your immune response won't be as strong leading to lower level of immunity.

I would note that that blog is from the US and specifically says there's nothing wrong if you simply have a mild sickness, it's particularly if you have a fever it isn't recommended. (To be fair, a flu is not likely a mild sickness unless in the early stages.) I'd also note it's written by a MD at the student health services of a university, and the way it's written it seems likely that this is based on how they handle things there so it's not simply abstract. It also mentions some health care providers are starting to think it may be better to do it anyway with fevers because people may not get the vaccine if asked to delay.

The CDC also mentions that only moderate to severe illness with or without a fever are a barrier [5].

Nil Einne (talk) 15:48, 22 October 2019 (UTC)[reply]

Seto Inland Sea land reclamation

Were there any plans in the past to drain part or all of the Seto inland sea, reclaiming the area for farming and housing? Thanks. --2.37.200.57 (talk) 14:33, 16 October 2019 (UTC)[reply]

The notion of draining Setouchi may have arisen but been left to languish like that of Atlantropa because investors in such a project would be deterred by a geologist's risk assessment of the area prone to subducting sea plates, recurring tsunami-producing earthquakes and volcanos on the Pacific Ring of Fire. DroneB (talk) 15:03, 16 October 2019 (UTC)[reply]
Yes, some for industry and rice production, see Figure 35 here [6] (it's unlabeled). Some of the reclamation was under the 1962 plan of the Comprehensive National Land Development Act of 1950.—eric 18:41, 16 October 2019 (UTC)[reply]

October 17

Bacopa Monnieri

I got a bottle of this stuff in mail one day, charge free. Never heard about it. A quick check showed that people claim various cognitive benefits. Is anybody aware of any solid research on this plant? Thanks, - AboutFace 22 (talk) 02:02, 17 October 2019 (UTC)[reply]

Here's what WebMD has to say:[7] I notice several "might" qualifiers in there. ←Baseball Bugs What's up, Doc? carrots→ 03:47, 17 October 2019 (UTC)[reply]
FWI Bacopa monnieri Anton 81.131.40.58 (talk) 08:13, 17 October 2019 (UTC)[reply]

Touch and death

They say that a baby will die if it is provided with food, water, etc but never given human touch. Is this true of other animals? Temerarius (talk) 02:27, 17 October 2019 (UTC)[reply]

Can you supply any documented information about what “they” say in relation to human infants? It sounds like a myth. Dolphin (t) 02:36, 17 October 2019 (UTC)[reply]
There have been experiments with monkeys that show they do need a "mother", but that can just be a warm blanket with a monkey face mask, it doesn't need to be an actual monkey. And, of course, some animals are independent from birth, like sea turtles, so they don't need any such contact. Other animals that do need mothers can attach themselves to other species, in a process called imprinting. SinisterLefty (talk) 05:34, 17 October 2019 (UTC)[reply]
I presume you are referring to Harry Harlow's experiments in raising rhesus monkeys with various types of surrogate mothers. Whether these studies show that monkeys "need" a mother depend on what you mean by "need". In contrast to the claim in the OP, the monkeys raised without mothers did not die, although they were psychologically abnormal. I doubt that any similar study has ever been done with human babies, so I don't see how the claim in the OP that babies die without touch could be supported. CodeTalker (talk) 22:30, 19 October 2019 (UTC)[reply]

1st, 2nd law of thermodynamics and the rest

Are the first and second laws of thermodynamics somehow more important or for some reason to be singled out from the rest:

In University Physics by Young's index:

Thermodynamics
  1. Temperature and Heat
  2. Thermal Properties of Matter
  3. The First Law of Thermodynamics
  4. The Second Law of Thermodynamics

Only the first two are studied, at least in a separate chapter. Is that normal for a general textbook? C est moi anton (talk) 08:50, 17 October 2019 (UTC)[reply]

The reason why those two are singled out is that they have the greatest implications for most people. The first law is the law of conservation of energy and the second is the law of increasing entropy. The third law, which is merely a definition of zero entropy; is ultimately not that necessary since we can define a "zero" point anywhere and the other laws still work fine, after all we deal with concepts like energy and enthalpy just fine even though we have no meaningful "zero" point for those values, we just deal in "ΔE" and "ΔH", which is all we need to know anyways. The zeroth law of thermodynamics is a rather unsurprising law describing the transitive nature of energy; that is if state A is in equilibrium with state B, and state B is in equilibrium with state C, than A is in equilibrium with C. It's really only necessary to define thermodynamics as transitive for the sort of mathematical formalism necessary to prove certain other mathematical relationships, but it's not really all that broadly necessary for anything else. The first and second, however, have HUGE implications for the behavior of energy in the universe, which is why we focus on them so much. --Jayron32 11:10, 17 October 2019 (UTC)[reply]

Dating ancient artifacts that do not contain carbon

Would radiocarbon dating be of any indirect use here? That is, if they find a clay table buried with a bone, they can speculate that the former is at least as old as the latter. Are there direct methods for dating, at least for man-made artifacts? The relevant article Dating in archeology only mentions the existence of direct methods, but does ceramic, swords or glass deteriorate in a way that can be measured? C est moi anton (talk) 10:22, 17 October 2019 (UTC)[reply]

I don't think that any of those materials can be dated directly. Dating in archaeology, like geology, mainly relies on relative dating. The stratigraphy of the site is determined and then any dateable materials are analysed (using the methods listed in the article that you linked to) to provide fixed points in the site's chronology. The artefacts are then dated by comparison with these fixed points. Mikenorton (talk) 11:04, 17 October 2019 (UTC)[reply]
Apparently lead can be dated directly in some circumstances - as here. Mikenorton (talk) 11:25, 17 October 2019 (UTC)[reply]
Iron objects contain carbon:) See [8] for an article about dating iron objects. DMacks (talk) 13:37, 17 October 2019 (UTC)[reply]
Wouldn't clay also contain some carbon? C est moi anton (talk) 16:15, 17 October 2019 (UTC)[reply]
Clay tablets were generally dried rather than fired so any carbon in them would not record the date of the tablets themselves. Most clays anyway don't have a significant organic content. Mikenorton (talk) 16:46, 17 October 2019 (UTC)[reply]
Ceramics, including clay if fired, may be datable via Thermoluminescence dating or by Rehydroxylation dating. Some clay tablets were fired not intentionally but when the building storing them was burned down, as mentioned in the article linked by Mikenorton immediately above.
Some carved stone may be datable by Luminescence dating.
A particular artifact, irrespective of its nature, might be datable by various Geochronology techniques if it has been preserved in an applicable context, as implied in the OP and first response. {The poster formerly known as 87.81.230.195} 90.200.41.118 (talk) 17:24, 17 October 2019 (UTC)[reply]
Here's an article about using uranium–thorium dating of minerals to determine the age of cave paintings.[9] Another article lists a few other methods.[10] These non-carbon isotope measurements are indirect in that they analyze the properties of something found along with the artifact. The reason for using indirect methods depends on the material. For example, there are problems associated with dating the carbon in iron objects like swords.[11] This paper[12] lists some methods used for different non-carbon dating techniques for glass and pottery. (it is out of date and also behind a paywall) --mikeu talk 23:57, 20 October 2019 (UTC)[reply]

Are one-to-one comparisons between superlative physical traits of small animals versus large animals "fair"?

There's a new animal show on TV (Little Giants) that focuses a great deal on measuring some physical feat of a small animal and then breathlessly exclaiming about how if you scaled the feat up to human sized it would be so astounding. For example, that the giant horned lizard shoots toxic blood out of its eyes and the 3-foot distance it squirts the blood would be like it squirting the blood five football fields at human size (making up the numbers to give you an idea of what I'm talking about; not verbatim from show); or that the mouse lemurs' X-foot jumps between trees is like a human jumping Y feet, and so on (wow!).

I don't have the science background to back up my nagging feeling that the comparisons they're exclaiming over are not really kosher. Is this one-to-one comparison "fair", or is there some factor of "economies of scale" or something like that, that explains why these scaling comparisons are not as incredible as they seem? Does it really work like that? Or would, for example, a human scaled down to a tiny size also be able to throw much farther in comparison to their normal size because of the way the physical world works at the small versus large scale? Lady in polka dot (talk) 23:10, 17 October 2019 (UTC)[reply]

You are right to be skeptical. See square-cube law and, linked from that, allometry. --76.69.116.4 (talk) 23:49, 17 October 2019 (UTC)[reply]
In the case of squirting, increased air resistance from a high initial speed would also be a big factor. I think you can forget about crossing football fields with a small liquid. It probably evaporates or disperses long before the speed is high enough. The square–cube law is also a factor if you try to compare structures built by small animals like mound-building termites. They may be impressive but it's not like humans making skyscrapers. And there is a reason dragons are myth and real flying animals are small. They cannot compete with airplanes on fair terms. PrimeHunter (talk) 14:11, 19 October 2019 (UTC)[reply]

October 18

elements most similar to iron chemically

Would ruthenium or nickel be pretty similar chemically? It says that nickel doesnt rust as easily, so maybe not as far as oxygen is concerned—Actually i’m wondering what atoms could accidentally replace iron in hemoglobin if any, and thereby cause health problems.Rich (talk) 00:06, 18 October 2019 (UTC)[reply]

I could not tell you why neither of those metals are used as oxygen carriers, but the second most common biological oxygen-carrying metal after iron is copper, as in hemocyanin. Someguy1221 (talk) 08:39, 18 October 2019 (UTC)[reply]
In order to functionally take the place of iron in hemoglobin, an element would need to have both a similar atomic radius and a similar coordination number so that it would "fit" into the hole that iron is taking up. In general, the problem is not in iron being replaced in hemoglobin, but rather the oxygen. Carbon monoxide (CO) molecules have similar sizes and shapes, and orbital orientations to dioxygen (O2), and forms stronger bonds to the iron atom than does the O2, so it will tend to block O2 from bonding to the iron; which is how it kills you. --Jayron32 12:01, 18 October 2019 (UTC)[reply]

sorry, i don’t think that is relevant.Rich (talk) 05:18, 20 October 2019 (UTC)[reply]

Cobalt and nickel are pretty close: they are the other two members of the iron triad. And indeed, there is such a thing as coboglobin. Double sharp (talk) 12:15, 18 October 2019 (UTC)[reply]
doi:10.1021/bk-1986-0321.ch016 is about nickel–hemoglobin. I don't have full access to read it, but it appears to be discussing more physical-chemistry details rather than at the level of possible oxygen-transport ability. DMacks (talk) 18:21, 18 October 2019 (UTC)[reply]
doi:10.1016/S0006-291X(74)80185-3 is about manganese–hemoglobin (Mn is one to the left of Fe, so a bit larger and not part of the iron triad, but still redox-active). And doi:10.1021/bi00447a050 is about ruthenium/iron-hybrid hemoglobins (Ru is one below Fe, so noticably larger and the higher principle quantum number of the valence orbitals likely affects some of its bonding). That ref discusses differences in O2 binding. DMacks (talk) 06:46, 20 October 2019 (UTC)[reply]

Real-life mist from Stephen King

Inspired by watching The Mist movie and the series of the same name, do you guys think it's possible for the kind of mist seen in Stephen King's novel could happen in real-life in which strolling through the mist is dangerous either because there are monsters in them (as seen in the movie) or the mist itself that would take the life force out of the body (as seen in the series)? PlanetStar 08:20, 18 October 2019 (UTC)[reply]

No. Anton 81.131.40.58 (talk) 09:41, 18 October 2019 (UTC)[reply]
I suspect Brexit is more likely to "take the life force out of the body" than mist. Martinevans123 (talk) 10:13, 18 October 2019 (UTC)[reply]
My job takes the life force out of my body. But I have coffee before and beer afterwards; that seems to help. --Jayron32 11:50, 18 October 2019 (UTC)[reply]
Mmm, sounds great. Martinevans123 (talk) 12:09, 18 October 2019 (UTC) right on, Jayron. It was the great Jimbo Marx, wasn't it, who said, all those years ago, "Wikipedia is the opium of the masses"?[reply]
How can an adult like PlanetStar be so confused about the nature of fiction, and not know that reality does not include monsters or "life forces"? Was his account hijacked by a troll?--Lgriot (talk) 13:47, 18 October 2019 (UTC)[reply]
Not necessarily a troll. I know nothing about PlanetStar but could he/she have kids using the computer? -- Q Chris (talk) 14:01, 18 October 2019 (UTC)[reply]
Probably not a troll or hacking. See the response from this user on their talk page under the title "Reference desk" about a similar nonsense question posted 3 years ago. Richerman (talk) 14:41, 18 October 2019 (UTC)[reply]
Are you the one who keeps asking about SVU episodes? ←Baseball Bugs What's up, Doc? carrots→ 13:51, 18 October 2019 (UTC)[reply]
  • Nothing which Stephen King describes is possible. That's his style: everything in there – even if not obvious from the beginning – is based on something utterly outside human knowledge and experience. The Shining could be a story of psychological disintegration, but King bases it on something supernatural. The Stand could be a post-apocalyptic tale of bioweapons, but it turns into Milton. Misery is perhaps his only novel that has nothing weirder in it than humanity itself. But this means that King's scenarios can't be analysed. You can't look for the cryptozoology of Stephen King when it's impossible by design. Andy Dingley (talk) 16:01, 18 October 2019 (UTC)[reply]
I agree with Richerman that I wasn't trolling or being hacked. I'm being cool. I get inspired to ask even an outlandish question and have discussion about it. I'm well aware that such a possibility of that happening is extremely slim, if not zero. If it doesn't happen on Earth, it could happen on another world that have advanced civilization. In the movie The Mist, the military operation went wrong that they opened the interdimensional portal to let monsters along the mist into the main realm. Physicists suspect there are other dimensions, and some believe that another dimension can be accessed through portals (see interdimensional being). There are all sorts of secret military operations going on around the world. Many operations could come with just as many kinds of accident as a result, some could be the kind that could right now be only generally be talked about it in fiction. One example is cloning, which if they did something wrong could result in a monster that could attack or kill people. PlanetStar 02:12, 19 October 2019 (UTC)[reply]
Yes indeed. In her short seven years, I believe that Dolly exercised a brutal "reign of terror" across the uplands of Midlothian. Martinevans123 (talk) 09:11, 19 October 2019 (UTC)[reply]
Strolling through poison gas will take the life force from your body. Monsters aren't likely to survive in it very well either, unless you are willing to accept microbial extremophiles as your monsters.-gadfium 05:16, 19 October 2019 (UTC)[reply]
A classic trope in science fiction is the chlorine-breathing alien monster, or even the silicon-based lifeform. They'd both be equally inconvenienced by our levels of oxygen. Andy Dingley (talk) 09:55, 19 October 2019 (UTC)[reply]
It is not only silicon-based lifeform can imaginably exist, but it's scientifically theoretical. Such a lifeform could exist on Saturn's moon Titan (see life on Titan). PlanetStar 01:51, 21 October 2019 (UTC)[reply]

Washing machines

Do washing machines typically revolve clockwise or anti-clockwise? Or does this depend on whether you're in the Southern or Northern hemisphere? 86.187.233.217 (talk) 21:45, 18 October 2019 (UTC)[reply]

Typically, neither. To prevent the laundry from tangling spirally on itself, the rotation direction alternates every few rounds. I once had a drier that was engineered by some half-wits that didn't used this tried-and-true method. It tangled bedsheets to the point I had to throw them away. אילן שמעוני (talk) 22:22, 18 October 2019 (UTC)[reply]
I think it's safe to say that in this big world different designs of washing machine are likely to be common in different parts. In particular some places have strong preference for the more efficient front-loading design (which may have glass in the door so you can see how it rotates) but in North America the simpler top-loading design is also common (and I've never seen one with glass in the lid, but if you open it during the spin cycle, you can see which way it's turning). Likewise, in some places the same machine is commonly both a washer and a dryer. I can say that (unlike the preference of אילן שמעוני) I've never owned a tumble dryer, or seen one in a laundromat, that did not turn in a single direction. My current dryer, and my current top-loading washing machine, both turn clockwise as seen by a person using the machine. --76.69.116.4 (talk) 05:17, 19 October 2019 (UTC)[reply]
Intriguing. Now the only culprit I could think of is refuted. אילן שמעוני (talk) 07:33, 19 October 2019 (UTC)[reply]
Article link: Washing machine. Our top-loader has a glass lid. It's a newer model without an agitator, so just the bucket spins, and it does all kinds of fancy wiggling back and forth. Really great machine; I highly recommend it. --47.146.63.87 (talk) 02:07, 20 October 2019 (UTC)[reply]
Yes, top loaders have all sorts of advantages:
1) Simpler design, less prone to failure.
2) No large flexible rubber gasket required to prevent leaks out a front door. These tend to trap dirty water, which then turns foul.
3) Less likely to leak on floor.
4) More flexible in terms of adding and removing clothes without draining water. Useful when you discover you forgot something a few minutes in.
5) Safer for toddlers, as they can't get locked inside while playing with them. Even if they can get to the top door, it's only held shut by gravity, and isn't air tight.
6) Can be better for those with bad backs, as less bending is required. (Or the front-loader can be put up on a base, but that's rarely done, as it could fall off. You'd need to bolt it to the base, and bolt the base to the floor.) SinisterLefty (talk) 01:26, 23 October 2019 (UTC)[reply]
But if you have a top-loader, you can't stack the washer and dryer, which is an extremely popular thing to do in the UK. --Dweller (talk) Become old fashioned! 10:55, 23 October 2019 (UTC)[reply]
Although maybe not at night time? Martinevans123 (talk) 11:04, 23 October 2019 (UTC)[reply]
"Toploader refers to the way ammunition is loaded into a 7.62mm heavy machine gun used by the British Army." (not from a reliable source) --Dweller (talk) Become old fashioned! 13:43, 23 October 2019 (UTC)[reply]
Aww, what a let down. So they're not named after a washing machine.... unlike that other famous rock musician Jimi Bendox. Martinevans123 (talk) 14:05, 23 October 2019 (UTC)[reply]

Civil engineering accidents

Worldwide, is it common for individual civil engineers to be sentenced to prison when people die or bare injured as a result of engineering related accidents? 90.194.57.188 (talk) 21:46, 18 October 2019 (UTC)[reply]

Were you including blocks of flats with flammable exterior cladding? In such cases it seems to be more likely that the "Tenant Management Organisation" might be held to be criminally responsible, i.e. not even the local Authority, let alone the civil engineers who built the property. Sorry to focus on such a specific example. I guess many bridges fall down. Many buildings collapse. Martinevans123 (talk) 21:57, 18 October 2019 (UTC)[reply]
In Israel there were three such cases that reached headlines. A bridge under construction that collapsed on the motorway killing 3. A pedestrian bridge that crumbled under the feet of athletes, killing 4, and the collapse of a dance floor that killed 23. In all cases the engineers that ratified the work plans were sentenced to several years in prison, as well as compensating the families. אילן שמעוני (talk) 22:28, 18 October 2019 (UTC)[reply]
There is a very old legal concept known as gross negligence (see also negligent homicide), which is related to the concept duty of care. Basically, if you know that what you are doing could kill someone if you screw it up, and you fail to take reasonable measures to prevent that, you could be in a whole heap of trouble. Even Hammurabi's code contained laws regarding the liability of a builder to the victims of a collapsed building. In modern jurisprudence, though it of course varies by location, the negligence is really key. The fact that someone died or was injured is a component of the crime, but guilt hinges on how reckless the responsible person was. Someguy1221 (talk) 01:03, 19 October 2019 (UTC)[reply]
Wouldn’t it be the case that in many situations, it would have been a system failure or pressure from the company management though? Clover345 (talk) 09:41, 19 October 2019 (UTC)[reply]
In two of the cases I described it was sheer neglect. The engineer has a duty, by law, to oversee the construction and force it to be as planned, In the pedestrian bridge collapse the engineer didn't do that. The overpass disaster was, just as you said, due to constructors rushing the work, bringing pre-built sections that had not enough time to fully cure, plus planning on the assumption that the support beams would only suffer vertical load. The last case, the dance floor collapse, went far deeper than that. An engineer pushed his own invention technology into the market, hailing it as cheaper , faster to build an just-as-safe. It turned out his patent documents were heavily edited to cover basic flows. This became a problem because all of a sudden it turned out hundreds of buildings are to be promptly evacuated and condemned. This was beyond negligence. אילן שמעוני (talk) 11:18, 19 October 2019 (UTC)[reply]
To go further, it depends on the relationship between the construction and the engineer. If an engineer is hired to design or plan a construction, but his job is done before it even breaks ground, his duty of care may end at taking appropriate measures to ensure the plan is safe. He might bear no responsibility for a separate contractor entity messing things up. However, if an engineering firm is hired to manage the construction as well as plan it, then even if they subcontract the construction work itself, they owe some degree of duty to their client and to bystanders to actually monitor the work that is being done. You can arrive at a situation where several people are civilly or criminally liable despite playing different roles in a multiple-failure scenario. Someguy1221 (talk) 11:28, 19 October 2019 (UTC)[reply]

So in the former who was to blame? Clover345 (talk) 15:20, 19 October 2019 (UTC)[reply]

In most cases projects and leading Experts are insured and naturally the insurance will try hard to blame anyone they can to avoid having to pay for damage. "Independent" Experts will be used to survey the case and put the blame on someone, so it often ends up in a complicated settlement or goes on until one party gives up. --Kharon (talk) 16:36, 19 October 2019 (UTC)[reply]
(ec)Who is to blame in any given case could depend on the wording of the contract. ←Baseball Bugs What's up, Doc? carrots→ 16:39, 19 October 2019 (UTC)[reply]
Here's another opinion:[13]Baseball Bugs What's up, Doc? carrots→ 16:43, 19 October 2019 (UTC)[reply]
Could, yes. If the contract dictates whose responsibility it is to check for this, that or the other thing, certainly. But mostly that will impact the determination of whether a defendant should have known of a given danger. However, if it is not in dispute that the defendant did know of a given danger, it may not matter whether it was his job to know. The contract might impact liability of one contracting party to another in that case, but you cannot indemnify a business partner from liability where either statute or common law establishes a duty of care regarding known and foreseeable danger. For example, if you sign a contract that states your employer accepts all liability for your own behavior, even if reckless, you cannot use that contract to stop criminal or civil proceedings against yourself arising from your own recklessness. "But it wasn't my job to warn anyone" could get rejected by a court, especially if you are a member of a professional organization bound by a code of ethics. You might be able to use that contract to recover from your employer any penalties you are forced to pay, although that contract provision may be declared unenforceable by a court as against the public interest. Someguy1221 (talk) 00:38, 20 October 2019 (UTC)[reply]

October 19

New railway construction

When building new railway lines on flat land in areas with no civil engineering structures required, is the excavation and basic pavement laid down by the civils contractor or by the track contractor? Clover345 (talk) 08:54, 19 October 2019 (UTC)[reply]

That sounds like a matter for the railway company to decide when drawing up the contracts. --76.69.116.4 (talk) 10:03, 19 October 2019 (UTC)[reply]
It is different in many countries. In the US Amtrak is a private corporation handling most passenger lines. In China China Railway is a state-owned sole proprietorship enterprise. --Kharon (talk) 18:49, 21 October 2019 (UTC)[reply]
Amtrak isn't really a "private corporation" in the usual sense. And the context of this question is the trackage, not the trains themselves...Amtrak owns barely any of the track. DMacks (talk) 03:51, 22 October 2019 (UTC)[reply]

Length of spaghetti

Is all the spaghetti commercially produced 25.5 cm long? Why is this? The Wikipedia article on spaghetti says this: "Originally, spaghetti was notably long, but shorter lengths gained in popularity during the latter half of the 20th century and now it is most commonly available in 25–30 cm (10–12 in) lengths." But there is no sauce. 86.187.170.245 (talk) 17:16, 19 October 2019 (UTC)[reply]

Sauce is separate. It usually comes in jars. As to the size of grocery store spaghetti, that could be a function of convenience in fitting into an average cooking pan. (Plus, it fits the box.) ←Baseball Bugs What's up, Doc? carrots→ 18:56, 19 October 2019 (UTC)[reply]
Fairly sure the OP meant "there is no source", whether the pun was intended or not I don't know. Nil Einne (talk) 21:47, 19 October 2019 (UTC)[reply]
Oddly, spaghetti is often too long to fit into most cooking pots, requiring it to be broken in half, inevitably with a piece or two flying across the room and under the fridge, as a result. Is this an attempt by the companies to keep the mice in the house well-fed ? SinisterLefty (talk) 01:37, 23 October 2019 (UTC) [reply]
I don't know where 25.5 cm came from, did you try measuring your own spaghetti? Anyway at least in around 2005, "Barilla no. 1 dry spaghetti pasta of length L=24.1cm" according to [14]. BTW, Garofalo makes long spaghetti [15]. This may he a somewhat specialty product, but from the price e.g. [16] I'm fairly sure it's commercially produced by any reasonable definition of the term. That one quotes the length as 20.5 inches. It also basically says the same thing as our article as doe a bunch of other sellers of this spaghetti, but I'm hoping they copied use since it's been in our article since 2010 [17]. Nil Einne (talk) 22:06, 19 October 2019 (UTC)[reply]
I don't know why spaghetti is the length it is, but "everyone's standard spaghetti is the same length" (or simple multiple/fraction thereof" as a form of standardization lets one measure the amount of dried pasta one is using by the size of the bundle. DMacks (talk) 22:16, 19 October 2019 (UTC)[reply]
Such as with this very common tool (image to right): 70.67.193.176 (talk) 20:37, 20 October 2019 (UTC)[reply]
Spaghetti measure tools rely on the pasta having a uniform length
I see that it:Spaghetti tell us: "The longest spaghetti in the world has a length of 455 m and was made by Ranieri Borgnolo, on 10 September 2005 in Ober-Ramstadt (Germany). The record was recognized by the Guinness World Records and appeared in the 2008 edition." Martinevans123 (talk) 09:43, 20 October 2019 (UTC)[reply]
Comment: 25.5 cm is suspiciously close to 10 inches.  hugarheimur 12:20, 20 October 2019 (UTC)[reply]
Both spaghetti and inches were around long before centimeters were. ←Baseball Bugs What's up, Doc? carrots→ 17:38, 20 October 2019 (UTC)[reply]
Our Italian units of measurement article says that a former unit of length in Naples (the home of spaghetti) was "1 palmo = 12 once = 10.381 in" (about 26.4 cm). I doubt that Imperial or US inches were ever used in Italy. Alansplodge (talk) 20:05, 20 October 2019 (UTC)[reply]
The strange individuals at the Nottingham Science Blog bought a packet of cheap spaghetti and found that: "The lengths varied from 245 mm to 263 mm, with the mean being 256 mm". The object of this scientific endeavour was to establish the total length of a 500 g pack, the result was 148.6 metres. The editors added that "Alternatively, it could be used to cover a floor area of 51cm x 51cm (0.26m2)". Alansplodge (talk) 20:20, 20 October 2019 (UTC)[reply]
To cover larger floors, you'd probably need to go here. Martinevans123 (talk) 20:24, 20 October 2019 (UTC)[reply]
Depending on the width of the floorboards as compared to the length of the spaghetti, you can calculate the value of pi. DMacks (talk) 00:11, 21 October 2019 (UTC)[reply]
If we're going to get geometrical, how does Buffon cope with the square stuff? Martinevans123 (talk) 08:23, 21 October 2019 (UTC)[reply]
Well holy crap, we even have a Buffon's noodle article. All these seem to assume an infinitely thin noodle though, which I think is the reciprocal of a spherical cow. DMacks (talk) 12:39, 21 October 2019 (UTC)[reply]
Thanks for all of those. It certainly helps to bolster one's faith in Wikipedia. Martinevans123 (talk) 14:41, 21 October 2019 (UTC)[reply]
Both spaghetti and inches were around long before centimeters were Outright wrong due to anachronism in the context of "a spaghetti is a nice round number of inches", and at the very least misleading. Yes, "inch" dates back a millenium or so, but referred to very different units depending on time and location, whereas the metric system units have not changed since the end of 18th century (technically the definitions have changed for metrology reasons but every change in definition took care to hold constant the value within experimental precision at the time). Even if you keep to the British inch, per Inch#History, the definition was "three dry barley grains" or "some multiple of the average Scots height" up to 1824/1825 (when it was replaced by a multiple of the yard, the latter of which being defined as a fraction of a metric unit). TigraanClick here to contact me 13:29, 22 October 2019 (UTC)[reply]
There are sometimes standards that specify the dimensions and other characteristics of food products. This USDA document[18] classifies spaghetti as a "Type VI" pasta with a length of 8 1/2 to 11 inches and a diameter of 0.060 to 0.110 inches. (ziti is 1 1/4 to 2 inches long) The ~10 inch length cited above falls near the midpoint of that range. For optimum cooking time see ISO standard 7304-1 (preview only of first few pages, so I'm not sure if it defines al dente.) Bon appétit! --mikeu talk 22:34, 20 October 2019 (UTC)[reply]
Maybe they're just harvesting it earlier these days.--Shantavira|feed me 08:13, 22 October 2019 (UTC)[reply]

October 20

Cells

What elements are cells , for example , the ones in the flesh in our arms , made of ? — Preceding unsigned comment added by 2401:4900:3145:b505:e818:41b4:a5a5:628e (talkcontribs)

Do you mean Chemical element in the technical sense, or in the more informal sense of "part"? Either way, Cell (biology) would be a good place to start. Alternatively, this Wikibooks page lists the (chemical) elements in a "typical cell", and their proportions. AndrewWTaylor (talk) 17:35, 20 October 2019 (UTC)[reply]
We also have Composition of the human body. Someguy1221 (talk) 19:01, 20 October 2019 (UTC)[reply]
Yes, the cells will be made of the same elements as the parts of the body outside the cells, such as blood plasma and lymphatic fluid, although perhaps at different ratios. SinisterLefty (talk) 01:59, 23 October 2019 (UTC)[reply]

Microwaving metal

I've accidentally microwaved forks a bunch of times. No sparks, no explosions, no problems. Why? Temerarius (talk) 15:46, 20 October 2019 (UTC)[reply]

If you place an antenna into a microwave oven, it will have a voltage and current induced across and along it. That's not necessarily a problem. If it's a fork, then there's really not much which is going to annoy a fork. It also needs to be a big enough fraction of a wavelength to act as a useful antenna - about an inch and a half. There are a few ways to have this go exciting:
  • (the favourite) Place the metal thing so that it passes near the earthed metal case. As it does, there'll be an arc. As this can represent a large current, this is the one which might cause electrical damage to the oven (but modern ovens are designed to be idiot proof). I've killed the HT diodes in my workshop microwave enough times that there are spares inside the case.
  • Make a loop antenna with a gap in it. This is how Hertz made the very first radio detector. When arranged correctly, this would give a high voltage difference between the two ends, then an arc between them.
  • Use a susceptor, such as the thin tinfoil layer in microwave popcorn bags, but overheat it. This acts as an ohmic heater so unlike the fork, the resistance is high and the current causes the metal to heat up. That might pop your corn, it might set fire to your kitchen. I have a microwave glass kiln - a firebrick with a conductive lining - which uses this technique to melt glass. Andy Dingley (talk) 19:13, 20 October 2019 (UTC)[reply]
A CD incorporates a suitably thin metal layer. The most pleasing results are obtained by first dimming the light and using any album by the band Oasis. catslash (talk) 23:33, 20 October 2019 (UTC)[reply]
Placing a glass with a little water in it in the oven along with the CD will provide the oven with the sort of load that it is designed for. catslash (talk) 23:50, 20 October 2019 (UTC)[reply]
My lab microwave has among its design specs the minimum amount of various materials (and different values for high-absorbers line methanol and DMSO, medium absorbers like water and acetone, and low absorbers like chloroform and toluene) that gives sufficient total absorbance of the energy to prevent problems. DMacks (talk) 15:22, 22 October 2019 (UTC)[reply]
  • AD's answer explains why this is usually not a problem, but I once saw a notice for an old microwave (pre-1990) recommending to put a spoon when heating a cup of liquid (water, coffee, tea...). The likely rationale is to avoid spraying one's face with rapidly-forming steam due to Superheating#Occurrence_via_microwave_oven (I was pleasantly suprised to find that link; most of the time refdesk questions leads to a redlink or a very poor article). TigraanClick here to contact me 13:39, 22 October 2019 (UTC)[reply]

October 21

Car mechanics: 'real' SUV vs 'lifestyle' SUV

What's the difference between an SUV designed for offroading and an SUV designed for having a comfortable big car.C est moi anton (talk) 23:07, 21 October 2019 (UTC)[reply]

See Pretend SUV. catslash (talk) 23:29, 21 October 2019 (UTC)[reply]
  • Nothing simply definitive. It's all a question of degree. An SUV will be more robust, more capable off-road, less easily damaged, more easily cleaned, cheaper to repair, cheaper to buy. A good example is the Range Rover. The original 'classic' Range Rover from 1970-1993 was an extremely capable off-road vehicle. It also had rubber mats inside and (in early years) washable seats. In 1989 the transfer box was changed simply to make it quieter on-road for the US market and easier to drive for unskilled drivers. In the early '90s, it gained a more comfortable suspension which became rather infamous for its unreliability. In the mid '90s, followed by its gearbox. The modern Rangie can't even cross a kerb without bending a wheel rim, it's only useful for taking rappers to a club.
Most SUVs, old or new, are also quite poor at being cars. Real saloon cars are lower, so they simply go round corners more easily. Anything with the height of an SUV, especially if combined with the ride height (for ground clearance) that SUVs used to have will have problems cornering fast and will roll uncomfortably. Andy Dingley (talk) 23:31, 21 October 2019 (UTC)[reply]
For the interest of non-UK readers, in Britain 'luxury' SUVs used seemingly inappropriately by urbanites are jokingly referred to as "Chelsea tractors" (which term redirects to Sport utility vehicle) from their stereotypical popularity with well-off people in the upmarket London district of Chelsea despite their size making them difficult to manoeuvre and park in typical UK city streets. {The poster formerly known as 87.81.230.195} 90.200.41.118 (talk) 11:26, 23 October 2019 (UTC)[reply]
For an American automobile, the classic off-road SUV is a Jeep Wrangler, which are designed to be ridden hard and put away wet. They still have the DNA of the original Willys Jeep from World War II. At the opposite end of the spectrum is the Cadillac Escalade, which is just a large display of ostentatious wealth and conspicuous consumption, the upholstery and paint job certainly aren't designed for the kind of abuse a Wrangler is. --Jayron32 15:05, 22 October 2019 (UTC)[reply]
Even the first YJ Jeep Wrangler was softened a lot to make it easier to drive. The last 'original' Jeep line was the CJ series before that, up to the mid-'80s. Oddly, even in the mid 1980s, they kept leaf springs at a time when even Land Rover had abandoned them. Were they ever SUVs though? Or were they just too short? International Harvester's Scouts might be a more comparable example from that era. Andy Dingley (talk) 19:31, 22 October 2019 (UTC)[reply]
If you're thinking of the truck-body SUVs, I think the prototype in the U.S. is the Chevrolet C/K-body type Chevrolet Blazer/GMC Jimmy. --Jayron32 14:26, 23 October 2019 (UTC)[reply]
Being upscale and being functional off-road aren't necessarily mutually exclusive. Leather seats and a good sound system, for example, won't prevent travelling off-road. You do generally want a different suspension and gearing for off-road, and 4-wheel drive (or all-wheel drive) is a must, but these can be addressed by having these all be adjustable for the situation. With enough money, it's doable, even waterproofing with a snorkel for crossing streams. Of course, the paint job will get all messed up by driving through extreme environments, but maybe having it washed, detailed and waxed will still make it acceptable for a night on the town afterwards.
However, when trying to keep the cost down, it is necessary to make choices between ruggedness and comfort. The Jeep Wrangler, mentioned above, for example, isn't much of a luxury vehicle. SinisterLefty (talk) 01:49, 23 October 2019 (UTC)[reply]
Ironically the main difference is already in the initial question. "Lifestyle" SUVs are much more optimized for normal streets and roads and thus often a bad choice for real offroad duty. The most popular civil SUVs are in the luxury segment (Audi Q7 or Audi Q8) while "old school" Sport utility vehicles like Humvee are Utility vehicles with military origin. --Kharon (talk) 11:55, 23 October 2019 (UTC)[reply]

October 22

Ratel

Is there any relation between the Honey badger and the Wolverine. Their respective articles don't appear to link them and I found the Wolverine article to be a bit lacking on Latin nomenclature. They appear to be very similar in appearance as well as temperament and resilience. How close is the link between the two, considering we are all linked to some ancient fish or amoeba. Thanks Anton 81.131.40.58 (talk) 15:56, 22 October 2019 (UTC)[reply]

Both animals, as noted in both articles, are mustelids, and thus members of the same taxonomic family. Indeed, the Honey Badger article directly mentions the degree of kinship with the Wolverines, and both articles clearly show the taxonomic classification in the infobox on the right. --Jayron32 16:01, 22 October 2019 (UTC)[reply]

Enthalpy in introductory college level physics books

I was checking the index of some well-known physics books, and couldn't find an entry for 'entropy' 'enthalpy'. Isn't it a basic concept that should be teaching alongside 'quantify of hear' for example?

How do they choose what belongs in the category 'basic'? C est moi anton (talk) 22:35, 22 October 2019 (UTC)[reply]

As you haven't mentioned which books, how could we reply? Bleaney and Bleaney is one of the core textbooks of modern physics for over 60 years, yet it doesn't mention it until page 637. Andy Dingley (talk) 00:23, 23 October 2019 (UTC)[reply]
In Physics by Robert Resnick and David Halliday they adequately cover the flow of heat to and from a gas at constant pressure, and they also define the specific heat at constant pressure Cp, but they stop short of introducing the word enthalpy. Dolphin (t) 12:21, 23 October 2019 (UTC)[reply]
The question is not about any concrete textbook. It's about what belongs in an college-level introductory physics book. Is 'enthalpy' maybe too chemistry-ish to be included? C est moi anton (talk) 00:28, 23 October 2019 (UTC)[reply]
But is it a thermodynamics book? Entropy pops up in B&B (eventually), but enthalpy doesn't. Andy Dingley (talk) 00:40, 23 October 2019 (UTC)[reply]
The heading uses the word enthalpy, but the original question uses the word entropy. Since then, responses mention both. Enthalpy and entropy are significantly different. I have read all the answers but what is the question? (Enthalpy or entropy?) Dolphin (t) 01:33, 23 October 2019 (UTC)[reply]
It's about enthalpy. Sorry for the confusion. C est moi anton (talk) 02:16, 23 October 2019 (UTC)[reply]
A recent-ish editorial, Modernizing the Physics Curriculum by Being Less Modern, was published online at the website of the American Physical Society.
It is not the first that I've heard the argument; thermodynamics and fluid mechanics are often called out because they are featured less prominently in modern undergraduate treatments of physics compared to the curricula of previous generations of physics students. Each university selects its own syllabus. The syllabus is designed to provide education for the average student: specialists can and do pursue further study - and if they specialize in an area that needs a concept or skill, they will surely pick it up in multiple classes, or else they will learn it by indirect exposure to it.
We could quibble about whether enthalpy is helpful or useful for the average physicist; we might make the case that well-rounded physicist has a sufficiently general understanding of energy, and of general equations of state, such that "enthalpy" doesn't need additional special treatment. I am tempted to say that "enthalpy" refers to a particular operational definition for a specific form of internal energy that only helps in certain problem-domains (like the analysis of chemical reactions). Pure physicists prefer to generalize such expressions.
A couple of professors at my undergraduate institution became famous for their proposed introductory physics curriculum: APS cites Matter and Interactions on their list of research-based curricula - that is to say, there is experimental evidence to support the premise that students learn physics better when educated with this style of presentation and this curated list of topics. Notably, the heat engine is a supplementary chapter, rather than a primary topic of emphasis, in that book. In our curriculum, students in the physical and mathematical sciences would opt to proceed to study Physical Chemistry or Thermal Physics in an advanced course (e.g. over an additional semester or full year); or they could proceed down the engineering route (in which case they would study fluid mechanics and thermal engineering in another department); else, they could conclude with a degree in the humanities.
The "basic" classes taught to physicists, which would later be succeeded by multiple advanced courses, were very different from the "basic" classes taught to engineers to prepare them for further study in engineering domains; and those were different still from the "basic" classes taught to the humanities students as general education.
At the micro-level, if individual students needed more learning, they took another class; if the Engineering department didn't like the Physics course coverage, they worked to change it or supplement it; at the macro level, when empirical studies proved statistical success rates for students who followed certain curricula, other professors bought in to the books, and other departments and schools followed suit.
The point is, nobody decides what goes in the curriculum: prominent educators make proposals, and slowly influence the community of other educators by demonstrating some kind of positive educational outcome. And a positive outcome can be subjectively defined quite differently for different categories of students. So all we can really do is point to the presentations show up in popular books or in the classes of famous universities, and so on. Because... a good "basic" book for me might not be a good basic book for everybody else, depending on what we all want to get from reading it. I mean, golly..., what introductory textbook did M. Stanley Whittingham read as an undergraduate, and do you think he learned about enthalpy in it? ... and so what does that even matter, whether he did, or even if he did not? ...and did he include a chapter on enthalpy when he wrote his book on energy conversion and storage?
And finally, if you want to see what a physicist has to say about the difference between enthalpy and energy, here is Bruce Sherwood, an award-winning physics educator, on the difference between work and pseudowork. Chances are, if you see what any of this has to do with enthalpy, and why this demo is really more about atomic physics and thermodynamics than it is about strings and pulleys, then you're probably already a physicist; and if you can't see the connection, you're probably the type who needs somebody else to provide you with domain-specific state equations!
Nimur (talk) 05:08, 23 October 2019 (UTC)[reply]
Thermodynamics is a very specialized branch of physics or more fitting Engineering. Maybe similar like the term Thixotropy in Rheology. --Kharon (talk) 11:19, 23 October 2019 (UTC)[reply]
  • Enthalpy is covered in many chemistry courses as part of chemical thermodynamics. You'll find a discussion of it in any first-year college-level chemistry text book. You'll find more details in any physical chemistry course, where the things you learn in the first year class are expanded on. --Jayron32 12:18, 23 October 2019 (UTC)[reply]

October 23

Extrasensory perception and quantum entanglement

I wonder if there is a connection? I think it was Eugene Wigner who made a statement about it. He essentially said that consciousness is impossible without a quantum operation and that is the wave function collapse. There had been so many talks recently about quantum entanglement and quantum communications that it rekindled a long forgotten episode in my life. I was in a medical school at that time and a group of us got interested in "supernatural." We did Zener's cards and all the experiments failed. There had also been a talk about spontaneous extrasensory perception. I had a personal contact wish a person who claimed such experience. I don't remember his name and will call him Mr. X. The event happened decades before I met him, he published a skinny book, an account of what happened, and this is how we found out about him. This is what he said. As a young student he lived in a large metropolitan city away from his family. His father, a sick man, lived two thousand miles away in their family home. There was a caregiver involved, a young female. One day, at appointed time to give him a medication, she approached him with a glass with the medicine and a silver spoon. When she looked at him she realized he passed away. Startled she dropped the spoon in the glass which made a distinct sound of a bell ring. Mr. X claimed that he heard that sound at exactly that time.

It's important to give a characteristic of this man. He spent some years after that, trying to promote the possible research in the issue with no result since nobody wanted to deal with it. My understanding is that he never made a nickel out of his experience. He presented to us as an old, humble individual without much ambition or show off tendency. For him our visit was a chance to go down a memory lane once more since he lost interest in the problem long before we came. I am certain he told us the truth.

I lost interest in extrasensory perceptions long ago also but what if there is a connection between the two phenomena in the title? Thanks, AboutFace 22 (talk) 16:54, 23 October 2019 (UTC)[reply]

NO. Good god no. Extrasensory perception, in the sense of "magical powers to sense things no one else can" is unmitigated bullshit. Physicists even have a derogatory name for the "magic can be explained by quantum!" and it's quantum woo. Magical powers are not caused by quantum effects. Just no. --Jayron32 17:46, 23 October 2019 (UTC)[reply]
See our Articles Extrasensory perception and Quantum entanglement for an overview. I am not a professional in this but id guess the Hidden-variable theory seems the closest answer for the moment. --Kharon (talk) 17:52, 23 October 2019 (UTC)[reply]