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January 8

Cardiopulmonary resuscitation, oxygen in mouth-to-mouth artificial respiration

Since we exhale CO2, why does mouth-to-mouth artificial respiration help by CPR? Should we expire the air as soon as we inspire, holding our breath as short as possible, so to pump more oxygen into a patient?

I have not seen any indications regarding this issue. But is the artificial respiration meant to pump oxygen at all, or just to 'jump start' the breathing in the patient? --Hofhof (talk) 00:39, 8 January 2018 (UTC)[reply]

You're beginning with a mistake: We don't exhale CO₂, we expire a mixture of gasses that includes about 4 to 5% more CO₂ than we inhale. That is, the chemical composition of exhaled air is about 78% nitrogen, 18% oxygen, and 4% CO₂ (plus lesser amounts of other gasses). This is sufficent to oxygenate blood when inhaled. - Nunh-huh 01:16, 8 January 2018 (UTC)[reply]

The relevant article is at mouth-to-mouth resuscitation, which uses slightly different figures for exhaled oxygen levels (and backs them with a citation). If Nunh-huh has a better reference, s/he should update the article. Matt Deres (talk) 01:50, 8 January 2018 (UTC)[reply]

17% and 18% isn't a significant difference. The ref I used isn't better than the one in the article, though a better reference than that one is desirable, - Nunh-huh 02:36, 8 January 2018 (UTC)[reply]

I would argue that it is. Air is only 20.9% oxygen to begin with, so a one percentage point difference is pretty significant in terms of respiration efficiency. I was hoping gas exchange would have something better, but I'm not seeing much discussion of oxygen percentages (though there is a lot of text and I'm not familiar with the science). Matt Deres (talk) 03:03, 8 January 2018 (UTC)[reply]

I find your argument intriguing, and would like to subscribe to your newsletter. When we were taught CPR, I asked this very question, and was assured that some oxygen is better than no oxygen, and that we exhale a rather large fraction (they weren't specific) of the oxygen we breath in anyways. μηδείς (talk) 06:05, 8 January 2018 (UTC)[reply]

A 1% difference in a reported percentage that would vary widely in different measurements is certainly without significance. Variations in water vapor content and variations in metabolism will produce values for exhaled air in a wider range than that. - Nunh-huh 12:00, 8 January 2018 (UTC)[reply]

Yes, even assuming Air is 21% O2 and exhaled breath is 17% O2, you are looking at a 20% difference in saturation. Healthy people at sea level normally have a 100% blood O2 saturation, but people with sleep apnea can go for significant periods with a 70% saturation. And, again, 70% or 80% is much better than zero.

There is also the recent change in CPR guidelines which changes the initial order of steps from ABC (airway, breathing, compression) to CAB, so that the first step is compression. See Dragons flight on this below. μηδείς (talk) 15:53, 8 January 2018 (UTC)[reply]

In most places the latest guidelines for CPR recommend doing only chest compressions, without the mouth-to-mouth part. See Cardiopulmonary_resuscitation#History and also here. AndrewWTaylor (talk) 08:25, 8 January 2018 (UTC)[reply]

To clarify, CPR with rescue breathing is still recommended for trained professionals (as far as I know), and is believed to be of some benefit. However, it was found that when untrained or lightly trained members of the public tried to do rescue breathing they were so often confused and/or ineffective that there was often no benefit and in some cases additional harm when compared to performing chest compressions alone. So the new recommendation is for most people attempting to do CPR to just perform chest compressions, which provides most the benefit and is less likely to confuse non-experts. Dragons flight (talk) 12:20, 8 January 2018 (UTC)[reply]

This is covered in Cardiopulmonary resuscitation#Compression only which is linked in the history sectionl and also the effectiveness section. The particular cases where rescue breaths seem to offer some benefit is for children due to the increased likelihood the cardiac arrest has a non cardiac cause, and victims of drowning or drug overdose. Nil Einne (talk) 10:52, 9 January 2018 (UTC)[reply]

Good question! We mammals have a relatively inefficient respiratory system, where a lot of work is done pulling in air just to exhale it again. This is because we use tidal respiration, where the gas flow reverses constantly–you breathe in, and then breathe out through the same pathway. Gas exchange only occurs with air that's in contact with the surface of the alveoli; the remaining "dead air" is wasted. This is why there's still plenty of oxygen in the air you exhale. The "limiting factor" in our breathing is the need to get rid of carbon dioxide, not the need to get more oxygen into the lungs. The urge to breathe is, in fact, triggered by blood carbon dioxide levels. This is why you can painlessly asphyxiate from breathing carbon monoxide or an inert gas; you're still getting rid of carbon dioxide, so your body doesn't know anything's wrong. Rebreathers also exploit the fact that exhaled air has plenty of oxygen still in it. They just remove the carbon dioxide, and recirculate the rest of the air to be breathed again. Birds have a much more efficient respiratory system, where air flows in one direction throughout, minimizing "dead air". --47.157.122.192 (talk) 10:09, 8 January 2018 (UTC)[reply]

I am reminded that the advice given to those who hyperventilate due to anxiety is to breathe the same air several times using a paper bag [1] to increase the level of carbon dioxide in the blood. The usual advice is to do it about six times: the level of oxygen is clearly safe even when the same air has gone through the system several times. Wymspen (talk) 11:26, 8 January 2018 (UTC)[reply]

By its nature, hyperventilating puts out less CO2 per breath, so we can't compare those numbers directly. Carbon dioxide poisoning happens at a few percent (see the table there). Occupational guidelines on carbon dioxide are often quite a bit stricter, though I sense a strong lobbying influence from ASHRAE to turn the top floor of every major building into an HVAC shrine. Wnt (talk) 16:20, 8 January 2018 (UTC)[reply]

The point of the whole "breathe into a paper bag" thing is to artificially increase the fraction of inspired CO2 to compensate the respiratory alkalosis caused by hyperventilition with its attendent purging of arterial CO2.

How we use burning Energy?

Anlagenwirkungsgrade vs Anlagennutzungsgrade

Ich habe gelesen, auch in Pennsylvania wird Deitsch gschprochn, ein Dialekt welcher von vielen Amish gesprochen wird. Daß die Amish aus Glaubensgründen viele der uns lieb gewonnenen "technischen" Errungenschaften konsequent ablehnen ist bekannt. Im Hinblick auf eine gewünschte Reduzierung der Kohlendioxidemissionen möchte ich mit diesem Beitrag an die Community der Amish-People die Frage stellen inwieweit die Nutzung Photoelektrischer und solarthermischer Effekte mit Ihrer Lebensphilosophie vereinbar ist. Viele Gründe sprechen dafür sich der Kraft von Sonne und Wind zu bedienen. To collect the Energy from the Sun is easy and there are different Systems available they will produce Electricity or Heat by using the Physical Way. It is not Chemistry, when we use Collectors to catch that Photons, the Sun will deliver us most of the Days in the Year. What do Amish People think about Decarbonisation and Renewables, which can they use in the Future written by Umweltheizung - 4. January 2018 to translate into the "Deitsch" writing and speaking Wikipedia-Community in USA and Canada.

Isn´t it a technical and economical Process, How we are transforming Energy into Electricity and Heat? The Efficience is less than 70% and we can do that same with enormous higher efficiency Results. Using Renewables, like the Power of Wind and the Power of the Photons we could collect a lot of Energy, and transform into Electricity and we can save this Energy easy and cheap into hot Water Storage´s.

Anlagenaufwandszahlen|Diskussion — Preceding unsigned comment added by Umweltheizung (talk • contribs) 14:35, 8 January 2018 (UTC)[reply]

The Amish, many of whom have a "Pennsylvania Dutch" heritage and may continue to use Deitsch, have a strongly organized religious community that uses shunning to maintain an unusual degree of homogeneity. A chief goal of many of their beliefs -- including resistance to electrification and gasoline power -- is actually to preserve their independence from "the English" (who have since come to call themselves Americans). As such, renewable energy is clearly very appealing to their beliefs: [2] [3] It is already not uncommon to see Amish businesses that are well equipped with power tools, doing high quality technical craftsmanship. Wnt (talk) 16:30, 8 January 2018 (UTC)[reply]

The word "Deitsch" can refer to both the people and their language. The link Deitsch is a redirect to the article on the people, the article about their language is located at Pennsylvania German language. --Jayron 32 19:50, 8 January 2018 (UTC)[reply]

health effects of RF radiation

Hi, I came across a video that quotes some figures for health effects of Radio Frequency Electromagnetic radiation at various power densities. https://www.youtube.com/watch?v=QHkOdoDx-0c at 8:10. I am looking for this kind of data, which should form the basis of allowable levels of either power density or Specific Absorption Rate. I have not been able to find anything useful. Any help is appreciated. GilHamiltonTheArm (talk) 20:38, 8 January 2018 (UTC)[reply]

There is an article Electromagnetic radiation and health that may have some of what you need.

ApLundell (talk) 22:56, 8 January 2018 (UTC)[reply]

I should note that the video linked is quite the pile of batshit crazy. The gist is that electromagnetic radiation causes brain damage by interacting with "micro-antennas" delivered to the brain by mandatory vaccines. This is the level of crazy that, if this person says the sky is blue, go outside and double-check. I wouldn't take anything from the video as factual. Anyway, "health effects of radio frequency" is a very large subject. I think our article gives a decent overview, but if you have a more specific question, we could answer in better detail. Someguy1221 (talk) 01:58, 9 January 2018 (UTC)[reply]

OP: Hi again, I don't know how to make my question more specific. The level of mammalian excrement in the video is beside the point. I am looking for the data that underlies the officially determined allowable levels. There are health effects at high field strength and at high power density: I want to see the data, so I can determine whether the allowable levels make sense. GilHamiltonTheArm (talk) 08:00, 9 January 2018 (UTC)[reply]

This page of references from the U.S. Occupational Safety and Health Administration seems to have a wealth of leads to help you research the answers to your question. Here is a study from a journal called "Environmental Health Perspectives" that seems to be pretty good as well. Hope that helps some! --Jayron 32 13:49, 9 January 2018 (UTC)[reply]

Generally radio frequencies do no harm, even if you stand right next to a 100 kilowatt frequency generator, which i once did on a guided tour at a public day of a big radio station. I never forget the amazing trick the guide pulled of to show us how much power was in the air: He grabbed a standard big neon lamp tube, naked without anything connected, held it near the generator and it brightly lid up. Of course he enshured us that this causes no harm, not even when you spend your working life next to it.

The miracle with frequencies is simply about when they resonate (start to affect/swing) something - in our personal safety case water. Simply put you could safely sleep inside a 100 kilowatt radio frequency generator but you can not put your hand into a 700 watt Microwave oven for more than maybe 10 seconds - best not at all, ever. Simply put because the microwave frequency resonates with water and the radio waves dont. --Kharon (talk) 17:15, 9 January 2018 (UTC)[reply]

Microwave ovens actually don't cause water molecules to resonate [4]. Someguy1221 (talk) 18:42, 9 January 2018 (UTC)[reply]

January 9

Recommendations for non-science books by High Energy physicists

This is a question I could not easily find a good answer to on Google. I am looking for recent books by physicists, in particular physicists who work on fundamental research (as opposed to applied or e.g. condensed matter physics), on topics that range beyond just science to general cultural topics. An example would be Lake Views by Stephen Weinberg, or for older examples, The World as I See It by Albert Einstein or many books by Richard Feynman. Something written since ~2010, and by a well respected physicist, preferably. Any recommendations? 72.221.65.122 (talk) 03:50, 9 January 2018 (UTC)[reply]

Two recent books come to mind:

The Big Picture: On the Origins of Life, Meaning, and the Universe Itself by Sean M. Carroll

Life 3.0: Being Human in the Age of Artificial Intelligence by Max Tegmark

Gandalf61 (talk) 11:24, 9 January 2018 (UTC)[reply]

Thanks! 128.148.63.187 (talk) 23:23, 9 January 2018 (UTC)[reply]

Just to be clear, I assume you're excluding fiction (for which Gregory Benford or Robert Forward would be good examples)? {The poster formerly known as 87.81.230.195} 90.200.41.3 (talk) 14:46, 9 January 2018 (UTC)[reply]

Yes, I'm excluding fiction.

Any other suggestions? 128.148.63.187 (talk) 23:23, 9 January 2018 (UTC)[reply]

John Gribbin has some popular science/history of science books which are easy reads, such as In Search of Schrodinger's Cat and Schrodinger's Kittens. Brian Greene has also written some good, easy reads on similar subjects, such as string theory and the like. --Jayron 32 20:15, 10 January 2018 (UTC)[reply]

Supercritical power plants

General James M. Gavin Power Plant is a 2.6-gigawatt (2,600 MW) supercritical coal-fired power station in the village of Cheshire, Ohio, United States.

What does "supercritical" mean? Does it mean that this power plant operates by means of Supercritical steam generators, or something else? Nyttend (talk) 04:49, 9 January 2018 (UTC)[reply]

Presumably? I find multiple sources that simply call these "supercritical coal power plants" [5][6]. Someguy1221 (talk) 05:03, 9 January 2018 (UTC)[reply]

See Supercritical steam generator and Superheated steam. --Kharon (talk) 07:40, 9 January 2018 (UTC)[reply]

This term has nothing inherently to do with superheating or superheaters (NB the WP article is at superheater, not superheating), although it would be unheard of for such a plant to not also use superheating.

WP needs work on the supercritical and steam generator articles. They're mostly not inaccurate (but superheater is), but they aren't complete and they fail badly in explaining why a supercritical steam generator is useful. The term "steam generator" also has several meanings and the articles keep getting messed with and confused.

There is an inherent problem with steam boilers - steam is hard to transfer heat to. It is much easier to transfer heat to water (which is a convenient dense liquid) rather than steam in the low density, high volume, gaseous phase. The goal of any "boiler" is to transfer heat to a mass of water. This is so much easier when that mass of water is dense, i.e. liquid. The transfer can be done with a smaller area of heating surface, and the denser water can be moved around within a smaller boiler. Allowing the water to actually boil, although the ultimate goal of the boiler, is strongly unhelpful!

So a supercritical steam generator keeps the pressure high enough to avoid any boiling. It's arranged as a small number of long water-filled tubes before this (sometimes just one), wherein the water is heated. This hot, high pressure water is then allowed to expand (it may pass through a nozzle) and the drop in pressure allows it to boil immediately, without adding any further heat to it.

Most designs now avoid any single nozzle and instead use a long pipe the steam is allowed to boil gradually over a section of this pipe, but this is after most of the heating has taken place (using the efficient supercritical water phase). Lengthening the pipe after this allows superheating, where more heat is added, raising the temperature of the steam but without increasing its pressure in the normal equilibrium. This is useful because steam engines (steam turbines and a few of the later and more efficient piston steam engines) operate from heat energy within the steam predominantly as temperature, not just as pressure (as is usually thought).

As far as WP goes, WP should not be used as a source for this topic. It's nowhere near good enough, and (like electrical engineering) it keeps getting worse as a target for bad university projects encouraging first year students to trash articles. Andy Dingley (talk) 12:06, 9 January 2018 (UTC)[reply]

To be very basic, this refers to a supercritical fluid, which is denser than a vapor but hotter than a liquid. And typically hotter and more pressurized than the critical point (thermodynamics). That means that above the critical pressure, water can be "boiled" without ever boiling; it is simply heated up until it is a super-dense sort of steam (well, critical fluid) whose pressure could be reduced to form ordinary steam if desired, still without ever boiling. As the article says the lack of boiling means that there is no need to separate the steam from the boiling water with a big chamber prone to explosion; there's only one phase. The previous poster appears to know far more about this than I do, so I'll merely wonder out loud whether supercritical liquid–gas boundaries have any practical effect on the design of these generators. Wnt (talk) 22:10, 9 January 2018 (UTC)[reply]

January 10

Embryo segments (creationist claim)

Biological Anomalies: Humans by William R. Corliss quotes the following from a book called Flaws in the Theory of Evolution by Evan Shute (published 1961):

Homologous structures can arrive fro different segments of the body. In the newt the arm arises from segments 9 to 11, in man from 13 to 18. These "homologies" are not evidence of an ancestral relationship. They are largely accidental-- or artificial!

I can't find any discussion of this claim online, nor any explanation of the embryo segment numbers (which don't seem to be used anymore in embryology). Is this claim accurate in any way, and if so, what explains the apparent discrepancy? 169.228.152.135 (talk) 02:48, 10 January 2018 (UTC)[reply]

What explains the apparent discrepency is bullshit. You can safely ignore such arguments without giving them further consideration, they are generally some combination of outright lies and cherry picking specific things (usually not-as-yet explained things) rather than anything that resembles reasonable science. The proper response to such arguments is "..." --Jayron 32 11:43, 10 January 2018 (UTC)[reply]

Let's not be so touchy. There may be a difference, because the location of Hox gene activity (gene expression) varies a little between tetrapods; it is also possible that the response to it is different. In sort, evolution doesn't mean things stay the same - they can make use of the underlying genetic framework to move by making little tweaks here and there. The idea of paralogs is essential to this: one gene gets duplicated many times, resulting in genes that are similar but not the same, so that changing one of them just changes a few things, or so that becoming regulated by one rather than another with a small change in the DNA doesn't cause a drastic deformity. I don't have time presently to find the specifics of where newt limbs and Hox genes are; they're not in this review but you might find it helpful for general concepts.

The war between creationism and evolutionism is futile. You don't expect the text of a book and the author's notes on the book liner to agree about how characters in it came to exist. Wnt (talk) 15:18, 10 January 2018 (UTC)[reply]

This sort of thing is silly given our modern knowledge of genetics and embryology. An easy analog for non-biologists to understand is the turtle. Turtle evolution. The upper shell of the turtle is comprised of the back of the ribcage. In all other vertebrates with limbs, the limbs lie outside the ribcage, assuming the ribcage extends down as far as the hind limbs, which it often doesn't. In any case, think of your shoulderblades. They lie outside the ribs, not inside them. So God must have created the turtle especially, since its entire set of limbs lies within the ribcage. The limbs can't move through the ribcage during development, can they?

Well, the problem has been solved with clever study of embryology and the discovery of fossils which were unknown back when Jerry Fallwell was running the Moral Majority. The problem has been solved; science moves on; embryology is plastic; organisms evolve. It is human minds which sometimes do and sometimes don't catch up. μηδείς (talk) 18:27, 10 January 2018 (UTC)[reply]

Actually, the topic was addressed more recently, and while it certainly is a matter of evolution, the lack of known transitional forms means that a classic Haeckelian "ontogeny recapitulates phylogeny" approach provides us with the best insight so far. Wnt (talk) 00:27, 11 January 2018 (UTC)[reply]

Wnt, please look up projection (psychology). You call one editor touchy, then you "correct" (?) me by saying the issue has been addressed more recently? The time stamp I gave was Jerry Fallwell. He died in 2007, so was there actually any point in the "more recently" non-sequitur? Do us a favor, and apply your ample time and wisdom to making turtle evolution a bluelink. μηδείς (talk) 02:21, 11 January 2018 (UTC)[reply]

You said "back when Jerry Falwelll was running the Moral Majority" -- which was disbanded in 1987, according to our article. And you miss the point that as far as I could tell from the coverage I cited, we still don't have convincing fossils to illustrate how turtles altered the relations of ribs and pectoral girdle -- instead, we have an inference (a strong one) from observation of embryological development. Wnt (talk) 22:13, 11 January 2018 (UTC)[reply]

DST and India

As far as I know India doesn't use DST, but then why did they do so during Second World War ? Jon Ascton (talk) 19:23, 10 January 2018 (UTC)[reply]

According to Time_in_India, during the War India advanced clocks by 1 hour (war time) but it was not really DST as clocks were not adjusted twice a year. Ruslik_Zero 20:07, 10 January 2018 (UTC)[reply]

Indian Standard Time (IST) is the time observed throughout India, with a time offset of UTC+05:30. Compared with other countries, India lies close to the Equator (Jabalpur which is close the center of the land mass is at latitude 23°N) so that sunrise times hardly vary enough to justify the complication of DST which may have been viewed as an unwanted inheritance from British colonial rule, that it discarded at independance in 1947. Burma is similar while Bangladesh and Pakistan have observed DST in some years since WW2. Notes: Kolkata and Mumbai retained their own local time (known as Calcutta Time and Bombay Time) until 1948 and 1955. Daylight Saving Time (DST) was used briefly during the China–Indian War of 1962 and the Indo–Pakistani Wars of 1965 and 1971. see Time in India. SdrawkcaB99 (talk) 20:23, 10 January 2018 (UTC)[reply]

Two references: ^[1]^[2]

References

^ Pandey, Alok (3 January 2014). "India could get second time zone with Assam one hour ahead". New Delhi Television.
^ Kasambi, Meera (ed.) (2000). Intersections: Social-cultural Trends in Maharashtra. New Delhi. p. 176. ISBN 978-81-250-1878-0. {{cite book}}: |first= has generic name (help)CS1 maint: location missing publisher (link)

January 11

Does normal salt intake cause cardiovascular disease and high blood pressure by depressing the renin–angiotensin system?

We can read here that taking in very low amounts of salt (less than 0.1 grams a day) leads to elevated levels of aldosterone and renin and on the long term you then don't see the usual rise in blood pressure with age. So, could it be that by adding salt to our diets at the RDA levels (note that a few grams of salt is already 50 times the natural amount), we achieve a normal blood pressure but in the wrong way, and that this causes the blood pressure regulation to not work as well causing damage to the arteries on the long term that in turn causes arterial calcification which leads to hardened arteries and blood pressure rise? Count Iblis (talk) 00:36, 11 January 2018 (UTC)[reply]

Dude, you began with your own reference. Don't ask us to give medical speculation on it; read the guidelines. μηδείς (talk) 02:16, 11 January 2018 (UTC)[reply]

What guidelines???? Count Iblis (talk) 14:13, 11 January 2018 (UTC)[reply]

The ones that say we're not supposed to speculate here. We're supposed to provide reading material (references) in the form of reliable sources. Since you, yourself, just provided your own reference, and then ask us to speculate on it, Medeis is just noting that that sort of thing is not what we do here. It is explicitly written in the guidance at the top of this very page. --Jayron 32 15:28, 11 January 2018 (UTC)[reply]

Yes, Medeis is right, of course. It's entirely logical that a 42 year old suggestion in the literature would be taken to be the last word in the scientific community. Without even searching the literature, we can be 100% sure that there is nothing more to be found in the literature, therefore anything anyone could possibly have to say must be pure speculation, so let's hat this question! Count Iblis (talk) 15:45, 11 January 2018 (UTC)[reply]

I never said any of that. I'm not sure why you would want to hat the question now. Here is an overview of more recent studies about heart health and salt intake. Here are the most recent recommendations of the American Heart Association. The problem is that the phrasing of your question "could it be that..." is leading and an invitation to speculation. If you had phrased it "what is the current research on..." then you would have gotten a different response. --Jayron 32 15:52, 11 January 2018 (UTC)[reply]

Titanic

If they knew then what we know now about hypothermia, would it have been possible to save at least some of the people who died on the Titanic (I don't mean those who went down with the ship, but specifically the ones who jumped into the water)? Because the Carpathia arrived on the scene only a couple of hours after the great ship went down, and it's not exactly unknown for a hypothermic victim to be revived after such a time, right? 2601:646:8E01:7E0B:1DAB:D57B:F9C8:4AE0 (talk) 05:16, 11 January 2018 (UTC)[reply]

(Fixed your link.)

In the article you linked, the section Hypothermia#Prognosis suggests an answer of "maybe yes". Of course the number of victims who could be intensively treated would have been limited by the number on board the Carpathia who were qualified to do so. The best chance of revival would have been with children. Beyond these points we get into speculation, which we should not do here. --70.29.13.251 (talk) 06:56, 11 January 2018 (UTC)[reply]

According to our article Lifeboats of the RMS Titanic the Saveguard planning was insufficient and what was available was badly organized on top. Of course they already knew then that humans dont survive in ice cold water. The Titanic was not the first ship in history that sank in bad weather. Shurely with more Precaution almost everyone could have been saved. You can even argue if the captain had known a little more about Icebergs - but the big surprise is that everyone already knew back then everything important to know about icebergs. --Kharon (talk) 07:22, 11 January 2018 (UTC)[reply]

What I meant, though, was that we now know (but they didn't know then) that people sometimes DO survive in ice-cold water despite being mostly dead to all appearances (as the article on hypothermia points out) -- so my question was, with this knowledge alone, could they have saved more people even with all the other factors remaining the same? 2601:646:8E01:7E0B:1DAB:D57B:F9C8:4AE0 (talk) 09:45, 11 January 2018 (UTC)[reply]

Yes. ←Baseball Bugs ^{What's up, Doc?} carrots→ 10:23, 11 January 2018 (UTC)[reply]

How many extra lives could have been saved depends on what alternative history one cares to speculate. With the knowledge at the time of Titanic's sinking April 1912 it would seem obvious that earlier rescue with treatments such as a hot bath, massaging arms and legs, using a heating pad, and possibly giving alcohol could have saved more from death by Hypothermia. Today it is known that such treatments risk causing blood to be directed away from vital organs to the skin, see Hypothermia#Management. Modern recovery treatments for severe hypothermia such as extracorporeal membrane oxygenation (ECMO) or cardiopulmonary bypass, including cardiopulmonary resuscitation (CPR) for those without a pulse are most effective but they would have required a well equipped Hospital ship to be present at the scene. SdrawkcaB99 (talk) 11:50, 11 January 2018 (UTC)[reply]

Review of probable survival times for immersion in the North Sea from the UK Health and Safety Executive, on p. 22 points to the example of the Ocean Ranger, a mobile offshore drilling unit that sank in Canadian waters on 15 February 1982. The standby vessel arrived within 20 minutes of the sinking, but capsized a lifeboat while trying to rescue survivors. Those that fell into the sea could not hold on to the lifeboat or rescue lines and died. "It is apparent that in cold water sea conditions, the survivors who were not equipped with immersion suits succumbed within minutes to cold shock and hypothermia". I'll leave you to read through the rest of the data and evidence, but it's clear that two hours in the winter sea in your dinner suit is not survivable. Alansplodge (talk) 12:03, 11 January 2018 (UTC)[reply]

Circum-Rescue Collapse also makes interesting reading: "After the first Battle of the Falkland Islands [in 1914], it was reported that most of the 200 survivors from the German battlecruiser Gneisenau died on board one of the rescue ships". This underlines SdrawkcaB99's point above about the limited understanding of the condition at that time. The standard treatments used then are recognised as positively harmful now. Alansplodge (talk) 12:21, 11 January 2018 (UTC)[reply]

Cool flame

How did Sir Humphry Davy discover cool flame? Our article mentions that he produced the flame and accidentally noticed its coolness, but it doesn't mention what he did to produce it in the first place. All I'm finding with Google is numerous references to the fact of discovery, with (again) no mention of the process. Here's a good candidate for article expansion, if we can get a source. Nyttend (talk) 12:51, 11 January 2018 (UTC)[reply]

Reference no 5 in the cool flame article provides the answer - "H. Davy (1817) "Some new experiments and observations on the combustion of gaseous mixtures, with an account of a method of preserving a continued light in mixtures of inflammable gases and air without flame," Philosophical Transactions of the Royal Society of London, 107 : 77-86. On p. 79, Davy inserted a hot platinum wire into a mixture of air and diethyl ether vapor: "When the experiment in the slow combustion of ether is made in the dark, a pale phosphorescent light is perceived above the wire, which is most distinct when the wire ceases to be ignited. This appearance is connected with the formation of a peculiar acrid volatile substance possessed of acid properties." (though I do wonder if he really wrote vapor rather than vapour). Wymspen (talk) 13:09, 11 January 2018 (UTC)[reply]

Ah, sorry, I failed to check the references; I figured that whoever added the sources would have added the "how" if the sources supported it. Nyttend (talk) 13:14, 11 January 2018 (UTC)[reply]

January 12

Bizarre error in official PLU code record?

If you look up PLU code 3474 on plucodes.com, you see that it's something called "Saffron" sweet potato. If you drill down and look at the whole record, you get this info which says that the botanical name is Escobedia linearis.

Now, I don't know what Escobedia linearis is, but it's in a family of parasitic plants that includes Indian paintbrush and Pedicularis densiflora... and very little that is edible. I would be shocked if E. linearis bears anything that resembles a sweet potato.

It seems much more likely that the species here should be the ordinary sweet potato, Ipomoea batatas. But what does E. linearis have to do with anything, and why is it in the official PLU code data? —Keenan Pepper 01:43, 12 January 2018 (UTC)[reply]

The phrase "sweet potato/yam/kumara is used, which seems a tip-off that the common name is not very cladistic in nature. I haven't tried to figure out what this plant is, but I would be prone to suspect it might actually bear something that vaguely resembles a yam or sweet potato, perhaps saffron-colored. As with the common tomato, it is hard to guess whether a plant will bear wholesome fruit by looking at its relatives. Caveat: the image I found doesn't look like much of a potato! [7] (from [8]) Wnt (talk) 02:24, 12 January 2018 (UTC)[reply]

So you think E. linearis could actually produce food, and this be known widely enough that it has a standard 4-digit code for use in grocery stores? We should have an article about it! —Keenan Pepper 02:41, 12 January 2018 (UTC)[reply]

I don't know, but these PLU codes are published in multiple places; I'd think someone would have noticed. this source says that "azafrancillo" ('saffron', according to Google Translate) variety of sweet potato is indeed this species. Wnt (talk) 02:59, 12 January 2018 (UTC)[reply]

That link to kumara that you provided is inappropriate as it links to an article about a South African plant. Kumara (different language entirely) is indeed the Maori word for sweet potato, and in New Zealand it is, to my knowledge, a unique variety of sweet potato. It and its shade of meaning is discussed in the main article you linked to, so there was no need for the South African link. Akld guy (talk) 05:30, 12 January 2018 (UTC)[reply]

I agree that the link doesn't relate to what kumara is but I find your clarification equally confusing. Kumara is generally used for any sweet potato, or at least any of the 3 varieties common in NZ i.e. red (also sometimes called Owairaka or sometimes purple although there are also other recent imports often called purple), gold (also sometimes called Toka Toka or sometimes brown) and orange (also sometimes called Beauregard) [9] [10]. As far as I know, all 3 varieties are accepted to be derived from varieties introduced by European settlers or later, and don't share much in common with the varieties grown by Māori pre-contact [11] [12].

They may or may not be unique enough that they could still be called unique to New Zealand. My impression is that for at least one variety, the orange this isn't the case hence the alternative name Beauregard, see List of sweet potato cultivars. It may be what people in NZ sometimes think of when you mention sweet potato, if they don't just automatically translate it to kumara, given it looks similar to what I think is the most common "yam" or sweet potato in the US. (Although I'm not sure how many of those in the US are actually Beauregard even if it came from there. However from my experience, nowadays at least, everyone still just call it kumara or orange kumara or whatever. You sometimes hear sweet potato for very recent imports or those that haven't yet taken any real foothold here, although even then kumara is normally mentioned somewhere e.g. [13].

For further clarity the red variety is the traditional variety (i.e. it's what was probably considered kumara 50 years ago) and remains the most popular. But at least wherever I've been in Auckland, most fruit and vege shops, as well as supermarkets nearly always have all 3, and as said all called kumara. And if anything the gold is less common than orange nowadays. In fact [14] suggests orange could overtake red within 5 years (of 2017) due to changing demands.

There have been some attempts to reintroduce kumara grown pre-contact commercially, but these haven't been particularly successful as yet. As hinted at in the earlier sources and also others like [15] [16] [17], even finding these pre-contact varieties has been difficult.

Now this is English usage, but I'm pretty sure te reo is the same, or probably even more extreme. (I'm not sure if these's any term for sweet potato which isn't kūmara.)

Nil Einne (talk) 09:09, 12 January 2018 (UTC)[reply]

[18] has a better image. I do see some tubers. The source is Mexican and in Spanish, but machine translation of the description gives:

This tuber is used as a coloring and flavoring in certain stews; It is scarce, it is only present in one of the municipalities studied, Tacotalpa. It should be mentioned that the information regarding this species is scarce and is commonly confused with turmeric. The cultivation is of easy vegetative propagation due to the existence of abundant buds in the rhizome.

So it seems like the tubers are mostly used for colour and flavour rather than as a food source, which may explain why it's called "azafrancillo" or "saffron". I'm not sure why sweet potato is used, but maybe it is because it's the most commonly consumed tuber by the people who use it so "sweet potato" is something similar to "tuber". (You could probably say there are similarities with the word "yam" in English, and even more so with "corn".)

Nil Einne (talk) 07:05, 12 January 2018 (UTC)[reply]

BTW, it's also worth noting that given the large number of varieties, local growing conditions etc, even for something which is Ipomoea batatas people's mental picture is likely to vary. When I was in Malaysia, during Christmas I bought some kumara. The flesh and skin looked like what you'd call orange kumara in NZ but these very tiny, IIRC smaller even than what I'd call small potato. I don't know if I've ever seen a kumara in NZ that small. I think these were very small even by Malaysian standards as e.g. [19] those don't look very small although that's in Sabah no KL or peninsular Malaysia. And these in KL [20] although apparently from a prepared food or drink store rather than a market or supermarket also don't look that small. But even so, the point remains what rural villagers in Tacotalpa think of as a sweet potato may not be that similar to what you and I do even ignoring whatever colloquial usage and language translations issues that arise. Nil Einne (talk) 09:26, 12 January 2018 (UTC)[reply]

PID controller

PID controller uses the standard conventions for the gains, which is well and good:

K_{\text{p}}

is the proportional gain, a tuning parameter,

K_{\text{i}}

is the integral gain, a tuning parameter,

K_{\text{d}}

is the derivative gain, a tuning parameter,

But I'm dealing with a case where the PID controller uses this weird non-conventional notation:

K_{\text{P}}

is "Velocity gain" (note capital P)

K_{\text{i}}

is "Velocity gain"

K_{\text{p}}

is "Distance gain" (note lowercase P)

Since " $K_{\text{i}}$ " looks identical to " $K_{\text{i}}$ ", and has the right units (milliseconds), I'm assuming they map to each other. But what about $K_{\text{P}}$ and $K_{\text{p}}$ ? Which one map to the proportional gain and which one map to the derivative gain?

The acceptable range (according to the controller) of $K_{\text{P}}$ is 0 to 10, unit-less. And 1 to 5000 for $K_{\text{P}}$ , also unit-less. Mũeller (talk) 02:25, 12 January 2018 (UTC)[reply]

The quoted weird notation strongly suggests a mistake. The name proportional–integral–derivative controller must imply it has three different gain constants which correspond in reality or metaphor to velocity-distance-(de)acceleration respectively. Have you a reference such as a product specification or data sheet that shows this case? SdrawkcaB99 (talk) 10:16, 12 January 2018 (UTC)[reply]

Brown crap on people's teeth that doesn't go away

Sometimes I've seen people with brown who-knows-what on their teeth which stays there day after day. What's that all about? Is it permanent? How did it get there? I'm not talking about a diffuse staining from coffee or nicotine; but it looks like they've eaten recently and got some crap stuck to their otherwise normal teeth. I've seen this several times on different people I've known but I can only dream of the kind of social skill it would take to broach that subject without causing offence. 129.215.47.59 (talk) 17:46, 12 January 2018 (UTC)[reply]

Sounds like dental tartar. DuncanHill (talk) 17:48, 12 January 2018 (UTC)[reply]

Could also be dental fluorosis, standard tooth decay or celiac disease. Justin15w (talk) 21:28, 12 January 2018 (UTC)[reply]

I have brown spots on a couple of my own teeth where the enamel has chipped off, but there is no actual decay. At some point I'll get these covered up, but fortunately they do not show even when I smile. Someguy1221 (talk) 22:55, 12 January 2018 (UTC)[reply]

Bollockwarts

Is it true that orchids were once called bollockwarts as they can resemble testicles? The orchid page does not mention this.149.254.235.44 (talk) 22:32, 12 January 2018 (UTC)[reply]

Orchids are still called testicles, you just don't know it. The word is derived from the Ancient Greek ὄρχις (órkhis), which literally means 'testicle'. Though Google would suggest that no one calls them bollockwarts, now or in the past. Someguy1221 (talk) 22:50, 12 January 2018 (UTC)[reply]

Ah no. I its bollockworts . Can I have that as a user name?149.254.235.44 (talk) 23:52, 12 January 2018 (UTC)[reply]

Is "bollock(s)" considered a serious vulgarism in British English? If so, then probably not. ←Baseball Bugs ^{What's up, Doc?} carrots→ 00:47, 13 January 2018 (UTC)[reply]

Not really. I wouldn't expect to hear it in polite company, but compared with cunt it doesn't really have anything like the same impact. In fact describing something rubbish as "a load of old bollocks" is practically acceptable in many environments short of the vicar's tea party. There again I work with mechanics and engineers, swearing is a fact of life. Greglocock (talk) 02:59, 13 January 2018 (UTC)[reply]

Aside from a few comments on internet fora, I cannot find a good source to say that this word was ever used in that manner. One person claims it was once listed in OED, but the 1928 version that's available online doesn't list it. Anyway, it's not the job of Wikipedia to list every word ever used to describe a thing, though if the rumor could be verified, that would be something for Wiktionary. Someguy1221 (talk) 03:05, 13 January 2018 (UTC)[reply]

The word bollockwort does appear in the OED Third Edition (Revision of June 2008) as an obsolete word for a kind of orchid, but the two cites are from around 1300 and 1500 (the latter being from "Anglo-Saxon and Old English Vocabulary"). "Bollock grass" is another term for a type of orchid and has more recent usage. The word "bollock" was, according to the OED, "Apparently in standard use until the 17th cent., after which the word is regarded as coarse slang." Dbfirs 08:31, 13 January 2018 (UTC)[reply]

There appears to be a German equivalent Hodenkraut. Cheers ✦ _hugarheimur 08:51, 13 January 2018 (UTC)[reply]

See also our article Bollock dagger for another example of the term being used without contemporary offensiveness. Contrary to some people's hopes, it refers to form rather than function. {The poster formerly known as 87.81.230.195} 90.200.41.3 (talk) 18:48, 13 January 2018 (UTC)[reply]

Our Bollocks article includes some research conducted by the BBC into the 'relative severity of the various profanities, as perceived by the British public'. The results, published in 2000, reported that "bollocks" came in at 'eighth position in terms of its perceived severity, between "prick" (seventh place) and "arsehole" (ninth place)'. So there you have it. Alansplodge (talk) 00:02, 14 January 2018 (UTC)[reply]

It's too much of a coincidence that the word bollockwort was mentioned on the BBC2 TV programme "QI XL" 24 hours after the question was asked here, so I wonder if our questioner has some connection with the programme? Dbfirs 07:53, 14 January 2018 (UTC)[reply]

When I see a discussion about this word, it's hard to resist posting a definition I came across in an old dictionary at the math library at UCLA:

*bollock* _Naut._ Either of two blocks attached to the topsail-yard in a ship, for the topsail-ties to reeve through
— Funk & Wagnalls New "Standard" Dictionary (Reg. U.S. Pat. Off.) of the English Language 1947

--Trovatore (talk) 08:28, 14 January 2018 (UTC) [reply]

The same sense of bollocks is recorded in C W T Layton's 1955 Dictionary of Nautical Words: "Blocks in bunt of topsail yards of large ships. Topsail ties are rove through them to increase lifting power"; and in A Ansted's 1898 Dictionary of Sea Terms: "blocks secured to the middle of the topsail yards in large ships; the topsail ties pass through them, and thereby gain an increase of power in lifting the yards." Dbfirs 12:15, 14 January 2018 (UTC)[reply]

Looking at a few images of topsail yards suggests that the nautical term may well derive from sailors noting a similarity to the relevant male organs! Wymspen (talk) 16:14, 14 January 2018 (UTC)[reply]

In 1977 the Sex Pistols relased an album entitled Never Mind the Bollocks, Here's the Sex Pistols. If you read the article you will find that a record shop manager who displayed posters for the album was prosecuted for displaying an indecent advertisement. During the case evidence was presented that bollocks was an Old English word for a priest and, in the context used on the album cover, meant "nonsense". The judge reluctantly ruled that the shop manager was not guilty saying "Much as my colleagues and I wholeheartedly deplore the vulgar exploitation of the worst instincts of human nature for the purchases of commercial profits by both you and your company, we must reluctantly find you not guilty of each of the four charges." So if you disagree with your priest tell him he's talking bollocks. Richerman (talk) 16:57, 14 January 2018 (UTC)[reply]

January 13

The Muslim Newton

Is The Book "Musalmano ka Newton" (The Muslim Newton) available in English Version? Danfarid133 (talk) 15:39, 13 January 2018 (UTC)[reply]

Musalmano ka Newton :Dr Abdus Salam (2003) مسلمانوں کا نیوٹن ڈاکٹر عبد السلام احمدی سپوت by Muhammad Zakaria Virk in Urdu is available for download here and here. The English Wikipedia article about the Pakistani theoretical physicist Abdus Salam will be of interest. SdrawkcaB99 (talk) 16:15, 13 January 2018 (UTC)[reply]

Is this book available in English or French.Danfarid133 (talk) 07:43, 14 January 2018 (UTC)[reply]

January 14

Nannostomus beckfordi in Rio Guapore?

I am having trouble finding info on whether Nannostomus beckfordi can be found in the Guaporé River. It seems commonly accepted that it inhabits the Madeira River and some of its tributaries, but I could not find a source mentioning the Guaporé River specifically. Surtsicna (talk) 11:01, 14 January 2018 (UTC)[reply]

Google suggests:

Nannostomus beckfordi Giinther. 14. Nannostomus ... The Rio Madeira-Rio Guapore collection consists of 31 individuals...

From:

Weitzman, Stanley H.; Cobb, J. Stanley (1975). "A revision of the South American fishes of the genus Nannostomus Günther (family Lebiasinidae)". Smithsonian Research Online. Smithsonian Contributions to Zoology.

—But I haven't figured out how to find it. —2606:A000:4C0C:E200:1D4C:29E3:6313:60B3 (talk) 23:31, 14 January 2018 (UTC)[reply]

Accelerating towards the sun

I was watching this video and it discussed how to hit the sun, and it asserts you have to cancel your orbital velocity in order to fall into the sun. But why can't you just accelerate towards it? Or even just given an initial velocity towards the sun, won't you hit it eventually? The rocket should still have a velocity vector aimed right at the sun correct? And in outerspace there's no friction to slow down your vector towards the sun so I would assume that you can still hit the sun simply by heading towards it. ScienceApe (talk) 13:08, 14 January 2018 (UTC)[reply]

Your total velocity vector is relevant, not a possible component you add towards the sun. Note that the Earth is continually accelerated towards the sun (by the gravitational attraction of the sun), yet never hits it (*knocks on wood*). Qualitatively, you can see it this way: If you are in orbit around the sun, you have a significant velocity perpendicular to the line from you to the center of the sun. If you add a small vector along that line, by the time you would have reached the sun, you've moved very much sideways, so you miss. And the added velocity vector is not even pointing towards the sun anymore. On the other hand, if you just cancel your orbital velocity, gravitation alone will accelerate you to the sun, and you will hit it. --Stephan Schulz (talk) 14:49, 14 January 2018 (UTC)[reply]

(ec) Orbital mechanics can be counterintuitive sometimes. (If you have the time, money, and inclination, Kerbal Space Program provides a thoroughly frustrating and delightful insight into the problems of manoeuvering in space.)

"The rocket should still have a velocity vector aimed right at the sun...there's no friction to slow down your vector towards the sun..." The problem is that your impulse toward the Sun adds a component to your velocity vector that points towards the Sun at the time that it's applied, but your rocket keeps its original momentum 'sideways' (that is, in the direction of its original orbit, or prograde) as well. That new velocity component that points at the Sun now will be pointing tangentially to it a quarter orbit later, and away from the Sun half an orbit down the road. The overall effect is that you go from your original nearly-circular orbit to one that's more eccentric (more elliptical, or 'squashed' and cigar-shaped), but still stable.

Additional inward burns will change that eccentricity (make the 'cigar' narrower or fatter) and/or rotate the axes of the orbit around the Sun (change the direction the cigar points); the degree to which one or the other occurs depends on where you apply that thrust in the orbit.

In principle, if you apply enough inward thrust over a short enough period of time, you can squeeze that 'cigar' down to be narrow enough that rocket grazes the Sun instead of sliding sideways past—but that's way more expensive than doing a retrograde burn (i.e. 'cancelling' your orbital velocity to fall into the Sun). TenOfAllTrades(talk) 15:16, 14 January 2018 (UTC)[reply]

Let me just point out the curious fact that it is possible to accelerate constantly toward the Sun (that is, always centripetally) without your orbit changing at all. If the equation a = v²/r holds, with a directed toward the Sun and v at right angles to the Sun, then you will move in an unchanging circular orbit. This actually shouldn't be a surprise, given that gravity creates a constant acceleration that is always directed toward the Sun. Looie496 (talk) 15:41, 14 January 2018 (UTC)[reply]

To try to give a more intuitive analogy, imagine you're in a boat in the middle of a river, being pulled by the current. You pick a point on one of the banks, at a ninety-degree angle to your direction of motion, and start moving towards it. By the time you reach the bank, you'll be downriver of the point you selected, because you continued moving with the current while you also moved towards the bank. In this analogy, the point on the river bank is the Sun, and your motion downriver is your previous trajectory relative to the Sun. Things move at high speeds in space, because there's nothing to stop them. It doesn't seem like it because our hard-wired intuition is designed for an Earth-bound environment; because the distances are so big and there's no "fixed" background to easily compare against, it looks like things in space are moving slowly if at all. For some numbers, the International Space Station, and other things in low Earth orbit, are moving at about 8 kilometers per second relative to you and me. That's much faster than a bullet fired here on the ground. They circle the Earth roughly every two hours. Similarly, we're all cruising around the Sun at about 30 kilometers per second. If you point yourself towards the Sun, you're still moving screamingly fast around it, and so (as noted above) you just wind up in a wackier orbit around it (because the Sun's gravity keeps you from flying off into deep space). Although, as TenOfAllTrades said, if you had infinite fuel you could eventually stretch your orbit out so much that you would take a dive into the Sun next time you went past, but there's no real point since that takes more fuel than the "right" way of adjusting your orbit. Also, depending on payload, there's no guarantee (very hot) stuff wouldn't pop back out the other side of the Sun, since you're just grazing the photosphere, which might be a problem if you were trying to get rid of whatever it was. This is one reason why the sometimes-raised idea of launching nuclear waste into the Sun isn't a good idea. This, I think, is good at explaining some more about orbits. --47.157.122.192 (talk) 10:24, 15 January 2018 (UTC)[reply]

Lying to children about science

When people teach children about complex phenomena like atoms (as composed by little balls orbiting around bigger balls) or DNA (as a building plan for living beings), could it be that we unwillingly making it more difficult to understand the real thing later on? Couldn't it even be that we are making them believe crazy stuff? --Hofhof (talk) 20:33, 14 January 2018 (UTC)[reply]

Would you start elementary reading classes by having them read Shakespeare? Or would you go for simpler stuff that they can more easily grasp? ←Baseball Bugs ^{What's up, Doc?} carrots→ 20:42, 14 January 2018 (UTC)[reply]

Don't "people" teach children that this was what was once believed, or that this is a first approximation? All scientific models eventually turn out to be approximations^[1]. This doesn't make them lies. Dbfirs 20:48, 14 January 2018 (UTC)[reply]

References

^ "truth … is much too complicated to allow anything but approximations".von Neumann, J. (1947), "The Mathematician", in Haywood, R. B. (ed.), Works of the Mind, University of Chicago Press, pp. 180–196.

The aricle you linked in the header discusses at length the value of the method, the risks, and the importance of choosing the correct lie to help learners get started but not get too misled for later learning. It even uses DNA as a specific example. DMacks (talk) 20:53, 14 January 2018 (UTC)[reply]

Maybe. As our article you linked to states, however, 'Worstall stressed that this form of educational methodology was ubiquitous across multiple academic disciplines: "This is true of any form of education by the way. We don’t start music classes with atonality, we start with simple scales. We don’t do syncopation until we’ve mastered 2/4 and 4/4. Einstein’s corrections at the margin to Newton come quite late in a physics education."' In other words, whether it leads to wrong-thinking or not, it is pretty much the standard way to teach everything... everywhere. Reality is horribly complicated; people would get lost if you started the ABCs with discussions about phonetics. Matt Deres (talk) 22:11, 14 January 2018 (UTC)[reply]

On the contrary, teaching a simple model can make it easier, not more difficult, to understand a more complex model later. If we don't teach simple models, then the human brain makes its own model, and can often get it even more wrong. Dbfirs 22:20, 14 January 2018 (UTC)[reply]

This is the right way. 00:16, 15 January 2018 (UTC) — Preceding unsigned comment added by Count Iblis (talk • contribs)

I would start by teaching scientific method, for young children just hypothesis and test (salt will dissolve in water but sand won't, maybe asking them about some less familiar substances). Then as they get older teach them about hypotheses, laws, and theories. That way, when you teach simplifications they will realise that these are not "lies" but hypotheses and laws that have actually been refined. I think a great example is Newtonian physics, and how it can be used to land a man on the moon, but not explain things like gravitational lensing. -- Q Chris (talk) 08:58, 15 January 2018 (UTC)[reply]

January 15

trying to identify a plant by pictures

I'm trying to identify a plant, shown in the following pictures, which resembles arecaceae, but it isn't a member of this family. The pictures were taken somewhere in ancient Caesarea in Israel, in October 2017. Also the purple cluster shown doesn't look familiar, at least to me. I'll be glad to get clear & professional identification. Some Yucca, may be ? Not sure.

unidentified plant from Caesarea, Israel

בנצי (talk) 15:12, 15 January 2018 (UTC)[reply]

How much care is exercised in naming new concepts in quantum physics? (e.g. "wave function collapse")

I understand naming standards like ISO for computer science and IUPAC for organic chemistry, but I don't know any details about the process of naming terms & concepts in quantum physics. Those I've asked in discord/reddit have said quantum physicists have bigger egos than computer scientists or chemists, which I find irrelevant. Hoping to find a more helpful answer here... Thanks, 67.233.34.199 (talk) 16:15, 15 January 2018 (UTC)[reply]

[1] Pandey, Alok (3 January 2014). "India could get second time zone with Assam one hour ahead". New Delhi Television.

[2] Kasambi, Meera (ed.) (2000). Intersections: Social-cultural Trends in Maharashtra. New Delhi. p. 176. ISBN 978-81-250-1878-0. {{cite book}}: |first= has generic name (help)CS1 maint: location missing publisher (link)

[3] "truth … is much too complicated to allow anything but approximations".von Neumann, J. (1947), "The Mathematician", in Haywood, R. B. (ed.), Works of the Mind, University of Chicago Press, pp. 180–196.

[1]

[2]

[1]