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October 4

Website showing heavens appearance at a given date

Hello! Is there a website that tells me where the sun and the planets were at a given moment in the past? I only know http://www.heavens-above.com, but there you cannot go very far in the past.

Thanks!

Megalexandros (talk) 02:16, 4 October 2017 (UTC)[reply]

In Wolfram Alpha, you can type "Sky map for [place] [time] [date]" and get a sky chart for then. For instance, "sky map for London 1 AM 4 October 1800" gives you this. Smurrayinchester 09:47, 4 October 2017 (UTC)[reply]

Stellarium is usually favoured for this. It's a downloadable program, but it's free and it's cross-platform. There are several others, and a list at that article. Andy Dingley (talk) 10:00, 4 October 2017 (UTC)[reply]

It's all carefully worked out [1]. 82.12.63.55 (talk) 11:16, 4 October 2017 (UTC)[reply]

Muscle and liver glycogen, which refills first?

When a person has fully depleted both their muscle and liver glycogen stores and then ingests carbohydrates, which refills first; muscle glycogen or liver glycogen? My understanding is that all carbohydrates will pass through the liver first because the blood vessels from the intestines go directly to the liver. However I have also read that the liver will not actually replenish its glycogen stores if blood sugar is low. Also, StuRat, as much as I love you (seriously, I do like reading your comments) I am looking for referenced answers to this question not just idle speculation :) Thanks for your time. 109.62.183.116 (talk) 15:46, 4 October 2017 (UTC)[reply]

That's fine, but why did you repost ? Is this a different Q from the one above ? Even if it is, I'd put it right after that one. StuRat (talk) 16:01, 4 October 2017 (UTC)[reply]

It's a different question. The other one was about both liver and muscle glycogen stores together acting as a cabohydrate sink during excessive ingestion. This one is specifically asking which of the two refills first. 109.62.183.116 (talk) 16:21, 4 October 2017 (UTC)[reply]

To simplify, the liver stores glycogen, the muscles use it. When I prepped for bariatric surgery last January I had to go on a strict three-week diet for the purpose of shrinking my liver's size by 75%. The doctor said the liver would shrink, making access to my stomach easier, but the muscles would have enough glucose as long as my blood sugar remained over 80.

I had to test three times a day, because your heart and lungs (and brain) have to have glucose at a sufficient level, while your liver will simply cut back on non-essential functions. No, that's not an RS, but I lived through it. I threw out the pre-op documentation, but it's easy enough to get if you google pre-op bariatric diet. 22:24, 4 October 2017 (UTC)

Shoot, if a person can diet well enough to keep blood sugar under 80 for three weeks and shrink their liver, why do they need bariatric surgery? Wnt (talk) 06:16, 6 October 2017 (UTC)[reply]

How old are you, exactly, Wnt?

Because it's an otherwise unhealthy starvation liquid diet, requires the use of very expensive, unsatisfying, and diarrhea and nausea inducing protein drinks, risks ketoacidosis, a potentially fatal condition, does not address the issue on the long term, and is not comfortable or cost effective?

Having had the laparoscopic over-night stay gastric sleeve surgery (which cost ~$10,000), I am off diabetes meds that had cost ~$12,000 year, am not on a starvation diet, and have lost over 50% of my pre-treatment body weight? And actuarial tables show I have added about 30 years to my expected life span. I am in better shape now than I was 25 years ago, and am unlikely to die or suffer amputations due to diabetic complications like about 1/2 of the people on my father's side of the family.

I'd give you the research, but I see no reason to humour medical conspiracy theorists. I feel, look, and test great. μηδείς (talk) 19:24, 6 October 2017 (UTC)[reply]

October 5

What is this thing?

Uploader has a local name for the bug. Claims a local discovered it. What is it? Magog the Ogre (t • c) 01:31, 5 October 2017 (UTC)[reply]

It's a caterpillar. Someone would probably need a location to get more precise than that.--Jayron 32 01:34, 5 October 2017 (UTC)[reply]

The file description page on commons has some clues, including a precise location in Kenya. Jahoe (talk) 09:17, 5 October 2017 (UTC)[reply]

Description says it's a centipede, but it looks suspiciously similar to a Saturniid moth larva to me O_o Dr Dima (talk) 20:07, 5 October 2017 (UTC)[reply]

It is certainly not a centipede. μηδείς (talk) 23:51, 5 October 2017 (UTC)[reply]

Looks to me like a caterpillar which is starting the process of forming a chrysalis. That part near the bottom appears to be the start of this stage. Here's another species at about the same stage in chrysalis formation (the one on the left): [2]. StuRat (talk) 05:27, 7 October 2017 (UTC)[reply]

Slide-fire adapter

In the reports and commentary about the latest (at time of writing) American ~~celebration of the Second Amendment~~ mass-murder there are many mentons of bump stocks and slide-fire adapters. Bump stock is a redirect to an article which has some information about them (as well as lots of hints for anyone wishing to murder lots of people). We do not appear to have anything about slide-fire adapters. What are they? DuncanHill (talk) 21:00, 5 October 2017 (UTC)[reply]

More or less the same thing. "Slidefire" (the company) are one of the main makers of bump stocks.

One difference, in historical terminology, is that a bump stock requires a semi-automatic (self-loading) weapon. A "slide fire" technique was originally applied to manually-loaded weapons, particularly pump-action shotguns, with a poorly-designed, faulty or modified trigger disconnector. Holding the trigger down on these and racking them (working the loading slide) they would fire the trigger mechanism as soon as the breech went back into battery. Andy Dingley (talk) 21:58, 5 October 2017 (UTC)[reply]

Thank you, DuncanHill (talk) 22:18, 5 October 2017 (UTC)[reply]

The shotguns are also sometimes called slam fire. Here is a video that compares how fast you can fire the two types: https://www.youtube.com/watch?v=0-csrQ_VP5Y --Guy Macon (talk) 22:32, 5 October 2017 (UTC)[reply]

Off-topic: I find the little jabs in your question a bit insulting to a lot of people, especially when you say you really have no clue about what you're talking about. Please refrain from the superfluous comments in the future. Justin15w (talk) 14:40, 6 October 2017 (UTC)[reply]

Has anyone seen any other notable uses of bump stocks this week? I think defensive gun use claimed there were something like 33 million of them. Jimbo forfend that we would offend anyone using one! Andy Dingley (talk) 14:57, 6 October 2017 (UTC)[reply]

One doesn't need to have an extensive technical knowledge of firearms to have a valid opinion about mass murder and its enablers. DuncanHill (talk) 15:21, 6 October 2017 (UTC)[reply]

I think slamfire is the most relevant article here. @Andy Dingley: By the way, can you source a number of bump stocks in circulation? It strikes me that a potential way to numerically establish thresholds regarding "advanced" weapons is to take the number of innocent casualties (i.e. not suicides, not the shooter, but including any other 'incidents' we may have missed...) and divide by the bump stock * years to get some kind of threat evaluation, which then can be compared to figures like here for other phenomena (a 1/625 crash rate per 10 miles drunk driving, though we still have to do some heavy philosophy to decide if a per-year comparison is relevant. If we're going to argue about gun control on the science desk at least let's do it with some kind of numbers and theory. (There is a pro version of this at [3] but I have to discard it because their cost is based on lost wages, i.e. if someone invents a gun that can only shoot the poor that would be considered OK, but one that shoots the rich is not; note it is certainly possible to invent that sort of gun with facial recognition and a no-shoot list. I think a simple per-life number, presuming wounds are proportional, is far more productive) Wnt (talk) 05:48, 7 October 2017 (UTC)[reply]

October 6

Can electron quantum tunnel out of a black hole?

If a single hydrogen atom is just at the event horizon of a black hole. Can it's electron quantum tunnel from inside the event horizon to outside it. After all, its location is just a wave function and half of the wave is inside the event horizon and half of the wave is outside the event horizon. 110.22.20.252 (talk) 01:56, 6 October 2017 (UTC)[reply]

Hawking radiation is at least a bit relevant. Sagittarian Milky Way (talk) 02:15, 6 October 2017 (UTC)[reply]

Yes, there are generally theories that quantum mechanical effects will allow particles to escape from black holes, albeit with a very low probability. However, as we lack a comprehensive theory of quantum gravity or any direct experimental access to black holes, I would suggest such ideas are rather speculative at present. I would note though that unless you have some magic way of suspending matter right at the event horizon, then the atom is likely to be falling into the black hole at very high speeds. The amount of time that any atom might be considered half-in/half-out of the black hole is likely to be extremely small for any normal black hole. The situation is more interesting in the case of microscopic black holes, if such entities actually exist. It is possible to imagine, at least in theory, black holes so tiny that particles like electrons are essentially too large to fit in the black hole and even after being eaten there is an appreciable chance that they leak back out again. Again though, this all rather speculative and untested. Dragons flight (talk) 02:55, 6 October 2017 (UTC)[reply]

Jak skazal SMW, see Hawking Radiation. μηδείς (talk) 00:50, 7 October 2017 (UTC)[reply]

What does jak skazal mean? Sagittarian Milky Way (talk) 01:18, 7 October 2017 (UTC)[reply]

Limit of temperature generated by electricity

Hi again ref desk, another impossible to Google question. I heard on a podcast about converting the world to renewables, that creating steel requires around 3000°F and they claimed that using electricity alone, you can't get to those temperatures. So, is this true? If so, given an infinite amount of power, is it a law of diminishing returns? I was thinking they could just turn large chunks of iron into filaments (however impractical) to accomplish this. Anywho, thanks in advance. Drewmutt (^ᴥ^) talk 04:35, 6 October 2017 (UTC)[reply]

No, not true at all. Our article on electric arc furnaces says that they can reach temperatures of 3,000 °C (5,432 °F). 2601:646:C101:C8A2:34D5:864B:CE64:F9CD (talk) 05:46, 6 October 2017 (UTC)[reply]

That just the furnace. The actual arc is hotter.

"Electrical arcs produce some of the highest temperatures known to occur on earth, up to 35,000°F (19,426°C). This is 4 times the temperature of the surface of the sun which is about 9000°F (4982°C)."[4]

BTW, it took me roughly a minute on Google to find the answer to this "another impossible to Google question". I'm just saying. --Guy Macon (talk) 06:53, 6 October 2017 (UTC)[reply]

(ec)Maybe we should also mention that many high-quality steels are routinely produced in electric arc furnaces (and have been for at least decades), because they offer more control over the chemical composition of the steel (there is no coal to introduce carbon, or other undesirable impurities coming with coal, like sulphur and phosphorous), and they also make the physical process easier to control. Of course there also is a red herring - just because it is hard to replace some fossil fuel applications does not mean that we cannot reduce carbon emissions to a sustainable level - most carbon emitting processes can be replaced or improved. --Stephan Schulz (talk) 10:00, 6 October 2017 (UTC)[reply]

As pointed to above, the problem is not the maximum temperature. But a key consideration is that coal is used to bring not only heat but also carbon content to the steel in blast furnaces (historical note: Wootz steel), which can help the economics of coal vs. electricity - you would need a source of carbon if you heated by electricity.

Blast_furnace#Iron_blast_furnaces says that there have been electrical blast furnaces in Sweden but I cannot track down a source. I found this report considering switching to biomass (which counts as "renewable" by most standards). Tigraan^{Click here to contact me} 09:46, 6 October 2017 (UTC)[reply]

I would also note this, from our article on Tantalum hafnium carbide: " Tantalum hafnium carbide is a refractory chemical compound with a general formula TaxHfy-xCy, which can be considered as a solid solution of tantalum carbide and hafnium carbide. Individually, these two carbides have the highest melting points among the binary compounds, 4,150 K (3,880 °C; 7,010 °F) and 4,201 K (3,928 °C; 7,102 °F), respectively, and their "alloy" with a composition Ta4HfC5 is believed to have a melting point of 4,263 K (3,990 °C; 7,214 °F). Very few measurements of melting point in tantalum hafnium carbide have been reported, because of the obvious experimental difficulties at extreme temperatures. " (Emphasis added) --Guy Macon (talk) 16:20, 7 October 2017 (UTC)[reply]

Global warming

So when people think global warming is made up, what is their reasoning for why they think scientist would just make it up? Is it just random conspiracy nuts? CTF83! 09:30, 6 October 2017 (UTC)[reply]

It's very much not random - it's carefully seeded by people and organisations that profit from the old-school carbon-based economy and want to reduce or delay changes. A modern classic on the topic is Merchants of Doubt, but you will find plenty of additional sources via Google Scholar. --Stephan Schulz (talk) 09:40, 6 October 2017 (UTC)[reply]

There are not many global warming denialists. Temperature is quite easy to measure after all. Denialists mostly deny it's man-made, and hence, believe nothing should be done.

They normally explain the consensus as a result of aggressive activism, as a Chinese invention, or whatever. See Global warming conspiracy theory for the whole story. --B8-tome (talk) 11:45, 6 October 2017 (UTC)[reply]

To be fair, those of us who grew up in the 1960s and 1970s were regularly served up gloomy scientific predictions; the world would run out of food or water (or both) at some time in the 1970s, we could be thrown back into the stone age by a power cut, we would completely run out of oil in 1984 and millions would die when the next ice age arrived early in the 21st century. So although I agree fully with what Stephan Schulz says above, there has been an awful lot of crying wolf beforehand, so some scepticism is understandable. Alansplodge (talk) 12:06, 6 October 2017 (UTC)[reply]

The reason I've heard is funding, that if global warming wasn't real, climatologists risk losing their funding. A Quest For Knowledge (talk) 12:15, 6 October 2017 (UTC)[reply]

Because as a rule scientists are motivated by money and choose their profession because scientific careers pay so well? Or because there is a hive mind controlling all scientists? Note that anyone who puts a serious dent into a widely accepted theory would be set for life - compare Albert Einstein (who killed Newtonian mechanics), or Barry Marshall and Robin Warren, who showed that most gastric ulcers are caused by infections, and not (directly) by stress and diet. --Stephan Schulz (talk) 13:37, 6 October 2017 (UTC)[reply]

It isn't just because it is in the interest of some very big companies, there is also a desire in people to not believe they are doing any wrong by driving cars or taking holidays by plane or any of the other countless good things of modern life that need fuel to be burnt. And in particular in America it basically says you can't be altogether free to do whatever you like which is one of the beliefs the country was built on. So lots of people are quite happy to engage in what psychologists call denial. Dmcq (talk) 13:55, 6 October 2017 (UTC)[reply]

As hinted above, there is a habit of grouping anyone and everyone who disagrees with anything at all about global warming into the "stupid denier" section. If I were to point out a prediction from Gore's Inconvenient Truth that didn't happen, I would immediately be as much of a denier as some guy who claims that it is all made up by the illuminati. 209.149.113.5 (talk) 17:25, 6 October 2017 (UTC)[reply]

That is simply not true. Scientists were quite happy to point out some problems with the film An Inconvenient Truth. They didn't however make the leap from that Al Gore made some mistakes in his film to that global warming isn't happening. Dmcq (talk) 15:37, 7 October 2017 (UTC)[reply]

Ok thanks all! CTF83! 17:30, 6 October 2017 (UTC)[reply]

It is because the vast majority of lay people (whether they have doubts about global warming or not), don't know much about how science works in practice. In particular, they lack knowledge about the rigorous review procedures. The way the media reports on science in general, not just about climate change, doesn't help. There is usually nothing in news reports about science that gives you any clues how the review processes work. Because usually the news media will try to interview the leading experts in the field, this then leads to a skewed picture of how science works, it then looks like professors ultimately decide what is going to be accepted as proven facts. Then some lay people will find that reasonable, while other people who have read elsewhere that all these professors are left wing liberal tree huggers, cannot be trusted, will have severe doubts.

Contrast this with the justice system. People know a lot more about the procedures of that system and the way the media reports about crime and court cases usually will contain something about the relevant procedures. Then, without even reporting about the details of the evidence that led to a conviction, most people will typically accept the verdict. In exceptional cases there may be doubts, but even in such cases were someone is alleged to have been wrongly convicted, will people still argue that there should be a retrial based on e.g. new evidence. So, people know about the procedures of the system and at most they would want a new hearing within the system. In case of global warming, the deniers buy into arguments presented outside the system and they want conclusions reached via the procedures of the system to be ignored. That's analogous to releasing someone convicted of murder based on a newspaper editorial without going through the procedures set out for that (e.g. appeal and retrial or applying for parole or pardon). Count Iblis (talk) 19:26, 7 October 2017 (UTC)[reply]

Is there a wikipedia article debunking the "Never Adjust for Curvature of Earth" claim of Flat Earth?

Is there a wikipedia article debunking the "Never Adjust for Curvature of Earth" claim of Flat Earth? Basically the stupid argument of flat earthers is that an aeroplane flying level on a spherical earth would fly off into space. Since the pilot of the plane NEVER adjust for curvature of the earth, the only conclusion a sane person can draw (with his kindergarten crayon) is an earth that is as flat as a pancake.

I know how to debunk it, it involves the vector from the centre of mass of the aeroplane to the centre of the earth. The aeroplane naturally balances itself on the centre of the mass, in the direction of the centre of the earth. So just imagine the aeroplane like a see saw with the pivot being the centre of mass of the plane. However it takes too much words, diagrams and effort to explain the idea to the Flat Earthers. So I am looking for a wikipedia article to explain this concept so that I can just direct them to the article. 110.22.20.252 (talk) 10:21, 6 October 2017 (UTC)[reply]

Gravity adjusts the plane for curvature of earth. That's like Earth is longeing the plane.

PS: I hope you don't meet many flat-earthers in your day to day. I have some just through the internet, and thought they were a parody of creationists. This was a classical case of Poe's law. --B8-tome (talk) 12:01, 6 October 2017 (UTC)[reply]

If those flat-Earthers admit the existence of gravity anomaly, it might be a starting point to argue that "gravity is not always vertical" (or rather, that if by definition vertical = in the direction of gravity, all verticals on Earth are not parallel), and the plane goes perpendicular to the gravity field, etc. But I am not sure of what is causing g in their world model, so... Tigraan^{Click here to contact me} 12:11, 6 October 2017 (UTC)[reply]

There are a few effects here. Conservation of energy is one, things just don't change their gravitational potential energy unless there is some trade of energy going on. So planes don't change altitude against gravity unless they're either driven by their engines, they perform a zoom climb and trade speed for altitude, or light gliders might climb in a thermal.

Then there's the classic balance between lift and weight, thrust and drag. When these are balanced, there's no vertical movement (Note to Newton - there's no vertical acceleration because they're balanced. But there's also no vertical speed because of the work against the gravitational field).

Finally there's the angle of attack issue. Aircraft move vertically because of the lift/weight imbalance. But flat earthers think aircraft "go where they're pointed" and so presume that any aircraft pointing "up" flies in that same direction.

Underlying all of this though, is the flat earth refusal of either gravity (at all) or their belief that gravity acts parallel and perpendicular to a flerf, rather than symmetrically and radially. Andy Dingley (talk) 12:15, 6 October 2017 (UTC)[reply]

Wikipedia has an article Flat Earth but does not as far as I know address this claim. If you get a reliable source discussing it then you could try adding it somewhere I guess. However I don't see the point of the question. No flat-earther is going to be convinced by some rational scientific argument about what a plane does or gravity or whatnot if they think pictures of the earth from space are part of some conspiracy theory. Dmcq (talk) 13:48, 6 October 2017 (UTC)[reply]

Flight instruments#Altimeter would appear to be relevant. The pilot will use his instrumentation to ensure his craft is an appropriate distance above the ground. This is important because aircraft are segregated laterally and vertically. 92.8.220.234 (talk) 15:19, 6 October 2017 (UTC)[reply]

So do you follow the flat earth claim here? That aircraft only maintain altitude, rather than flying straight above an Earth curving away beneath them and so heading off into space, because the pilots are deliberately steering them downwards?

Perhaps we need an article on the legal fallacy of riding two horses as well? Globe Earth aircraft maintain a constant altitude as an equilibrium, because of gravity. The same gravity shapes the form of the Earth too, so we end up with a constant gravitational height approximating a constant altitude over a plain. This is the same case for both globe and flat earth models.

The fallacy of flat earthers claims about aircraft depend on two underlying fallacies. Firstly that aircraft climb "by pointing upwards", rather than by having an excess of lift. Secondly, a flat earth aircraft would fly straight and level above a flat earth, and a globe earth aircraft would follow the same altitude around a globe Earth. The fallacy is to claim that a flat earth aircraft, following flat earth physics, would somehow be above a globe Earth, dropping away beneath it! Aircraft over a globe Earth are flying by globe Earth physics. Andy Dingley (talk) 15:50, 6 October 2017 (UTC)[reply]

This is serious. This is NOT A LAUGHING MATTER. THIS IS SO SERIOUS THAT a man took a spirit level on an airplane to prove that the earth is flat. [Man takes spirit level on an airplane]. 110.22.20.252 (talk) 16:42, 6 October 2017 (UTC)[reply]

The easiest way to understand why a plane does not fly off the Earth is to consider the frame of reference fixed with respect to that plane. In such a frame the plane is not moving at all but instead the Earth rotates beneath it. The air follows the Earth and moves relative to the plane creating a lift that balances the total gravity force. So, it is not surprising that plane stays bound to the Earth. Such a frame is, of course, generally non-inertial save one special case. However one of the two inertial forces – centrifugal force – is just added to the true gravity forming the total gravity force and is essentially unobservable. The second inertial force – Coriolis force – is small (depending on velocity relative to the plane) although it will readily reveal itself once you conduct a Foucault pendulum test. Ruslik_Zero 18:26, 6 October 2017 (UTC)[reply]

You are not going to convince a flat-earther with rational argument. See Duty calls for what I think about your capital letters about that this is so serious. Dmcq (talk) 18:49, 6 October 2017 (UTC)[reply]

Flat-earthers don't believe in gravity; they believe that the earth is accelerating upwards at the rate of gravity. If you think the Earth is a globe because you can see the curvature of the horizon, try this: take a long pole that you know to be perfectly straight from sighting along it. Grasp it at its centre with one hand; hold that arm out in front of you at full arm's length so that the pole is horizontal and level with your eyes. Look at the hand. Do you see anything unusual about the pole in your peripheral vision? Explain that. Akld guy (talk) 21:15, 6 October 2017 (UTC)[reply]

Talk about the amount of ignorance of physics. 99% of the youtube videos explaining why the airplane does not fly off the earth in a level flight is COMPLETELY WRONG. Right result but wrong explanations.

The air get more rare as the altitude increases, Therefore the airplane must curve with the shape of the earth. CORRECT STATEMENT but wrong explanation, I can prove this if you replace the plane with a rocket and take away all the air by moving it to the moon. A rocket with thrust (directed towards the centre of the moon) that perfectly balance out the force of gravity over the moon, will still curve with the shape of the moon. The air get more rare explanation is wrong.

Gravity makes the airplane confined to a certain altitude above the earth. TRUE but how?

The autopilot of the airplane keeps it curving with the earth. WRONG. The airplane will still curve even with no autopilot.

The trim of the airplane keep it curving with the earth by keeping it "level with the horizon". WRONG. See rocket on moon explanation. Trim needs air to work on an airplane.

The true answer is that the airplane is like a (weighing) balance scale which naturally balances itself by the centre of mass located at the centre of the aircraft by the wings. As the airplane travels an infinitesimal distance to the right, the front of the airplane dips down an infinitesimal amount and the tail of the airplane rises up an infinitesimal amount. This is because the airplane is like a (weighing) balance scale or a see saw. As it moves to the right, the vector from the centre of mass of the airplane to the centre of the earth changes. So the airplane becomes "unbalanced" and like a (weighing) balance scale or a see saw, it will naturally rebalances itself to make it level according to the new gravitational field. You can say the airplane ALWAYS forms a right angle triangle from the front of the airplane to the centre of the airplane to the centre of the earth. You don't need autopilot and you don't need any other explanation. 110.22.20.252 (talk) 04:09, 7 October 2017 (UTC)[reply]

It actually is possible, in theory at least, to use an airplane to test for a flat Earth. If you have an east-west route near the Equator, the Earth gravity you feel is adjusted downward (normally) by 0.3% for centrifugal force. Thus, if you fly 500 mph East, you should weigh about 0.15% less (adding to your speed and the centrifugal force), and if you fly 500 mph West, you should weigh about 0.15% more. In concept an analytical balance can weigh things to this accuracy. The caveat is, I have a hard time picturing that the vibration typical of a commercial flight would actually let you weigh that precisely. But I've never taken an analytical balance on board a plane! (Probably get sent to Guantanamo Bay just to be 'on the safe side') Wnt (talk) 06:21, 7 October 2017 (UTC)[reply]

Well, the basic plan is good. With a 100kg reference mass, you should notice 300g of difference going one way or the other. To handle vibration, just take a time series for each leg and average the results. There are two caveats: A balance (in the narrower sense) is useless, as the same reduction applies to the reference weights. You need a good weighing scale that directly measures force. Also, using yourself as a test mass is not a good idea - even if you skip the aircraft food (a small sacrifice, ok), it will be hard to maintain exact weight for a sufficient time, due to sweating and breathing. --Stephan Schulz (talk) 06:47, 7 October 2017 (UTC)[reply]

Wups, clearly you're right about the analytical balance - I should watch those last-minute "improvements". And no, you couldn't literally use yourself for a test mass... not unless you're one of those new robotic airline pilots, anyway. Wnt (talk) 10:49, 7 October 2017 (UTC)[reply]

Name of 'Bill Gates just walked in the room effect'

How would you call the statistical effect on income/personal wealth colloquially called 'when Bill Gates just walked in a room'?--B8-tome (talk) 11:41, 6 October 2017 (UTC)[reply]

?? [5]? Andy Dingley (talk) 12:04, 6 October 2017 (UTC)[reply]

This is related to the Ecological fallacy - the mistake of making assumptions about individual members of a group based on group averages. That article discusses a similar effect where the average wealth of US states is distorted by the super-rich. Smurrayinchester 12:09, 6 October 2017 (UTC)[reply]

Don't know the name, but this is used to show the importance of using median incomes instead of average incomes. If you have a billionaire in a room with a thousand homeless men, their average income makes them millionaires, but saying "the room contains a thousand people, who, on average, are millionaires", is highly misleading. Yacht salesmen would be advised to look elsewhere. The median income correctly shows that most people in the room are dirt poor. StuRat (talk) 14:21, 6 October 2017 (UTC)[reply]

This effect might work out to the benefit of Paddock's victims, given his supposedly high net worth, as long as they take Hamlet's advice on the lawyers. μηδείς (talk) 19:32, 6 October 2017 (UTC)[reply]

In statistics it is known as the outlier problem. Looie496 (talk) 13:17, 7 October 2017 (UTC)[reply]

Not sure if that's quite right. The problem with incomes is they do not follow a bell curve, but are extremely lopsided.Thus, any statistical methods based on even distributions, like averages, don't apply to incomes. StuRat (talk) 04:00, 8 October 2017 (UTC)[reply]

An actual reference:

"When Bill Gates Walks into a Bar". Introductory Statistics. 4 September 2011. — 2606:A000:4C0C:E200:CCE8:62C2:FF45:AE7B (talk) 05:46, 8 October 2017 (UTC)[reply]

Skin moisturizer as universal solvent ?

The first 4 ingredients in my skin moisturizer are water, mineral oil, stearic acid, and cetyl alcohol. So, it should dissolve substances which are water-soluble, oil-soluble, acid-soluble, and alcohol-soluble, right ? Is there some reason this is an important attribute in a skin moisturizer, or is this just a coincidence ? StuRat (talk) 14:29, 6 October 2017 (UTC)[reply]

Err yes & no. These are just the ingredients for making a Cream (pharmaceutical) which can be washed off. If you have a liquidizer in the kitchen you can make your own – and even eat what's left over. The important omega 3 fatty acids are left out of commercial products as they go rancid quickly and start to smell off. Aspro (talk) 15:37, 6 October 2017 (UTC)[reply]

That article says that water and oil are essential ingredients, and certainly for a moisturizer the goal is to add water to the skin, and oil is needed to hold it in and prevent immediate evaporation. That article also says an emulsifier and thickening agent are needed. Do the acid and alcohol serve those purposes ? If not, what do they do ? StuRat (talk) 16:38, 6 October 2017 (UTC)[reply]

From the stearic acid article: its primary use is as a "surfactant and softening agent" SemanticMantis (talk) 17:33, 6 October 2017 (UTC)[reply]

As I understand it oil & water are necessary to make a cream rather than a greasy ointment. The 'goal' of the moisturizer which one buys, is to generate profits for the share holders of the company. Any water can only affect the upper lays of the skin File:Skinlayers.png; like if one stays in the bath too long and ones fingers turn white and fingerprints expand, unlike bathing in sea water. No moisturizer on Earth will reach down to the lower layer where wrinkles form. Proprietary products use emulsifiers in order to combine oil & water (like egg yolks are used to combine the fat of dairy cream to make ice-cream and mayonnaise etc). See a dermatologist, for to find out what skin-care (note: I did not say treatment)suits your skin. If he says you have very thick skin – just point out to him, that as a WP editor -it is a necessity ;-) Aspro (talk) 17:54, 6 October 2017 (UTC)[reply]

I'm not looking for any medical advice, I only use skin moisturizer on my dry feet. Just wondered why it seems important for a it to be able to dissolve everything. StuRat (talk) 22:11, 6 October 2017 (UTC)[reply]

As an aside: Do you wear 'real' leather shoes and sandals? They (I assume) made the skin of my feet very thick around the edged of the heal. Assume it was the chromium tanning compounds leeching out and tanning my skin, stopping it flaking of in the normal way until they cracked and became sore. Found that with no leather no problem. Spanish leather riding boot etc' from Argentina don't seem to cause this effect. Maybe this is due to a different tanning process but anyway this all anecdotal. Aspro (talk) 20:51, 7 October 2017 (UTC)[reply]

No leather footwear, no. My issue is a poorly insulated home which therefore has dry air in winter, causing my lips and feet to dry out. This results in chapped lips and cracked skin on the bottom of my feet. I've tried humidifying the air, but it just condenses on the poorly insulated walls and windows and grows mold. Lip balm on my lips and skin moisturizer on the feet seem to solve the problem. StuRat (talk) 01:00, 8 October 2017 (UTC)[reply]

To be clear, "acid-soluble" isn't really a thing. The long hydrophobic regions of stearic acid and cetyl alcohol help make them useful as emulsifiers. So you have water and oil (mineral oil, so don't eat it) kept in some kind of creamy suspension. Either water or oil can make skin feel wetter, and together they allow a broader range of hydrophilic and hydrophobic compounds to be dissolved in the cream.

In concept, a chemical put on the skin can work its way all the way down to the bone (hydrofluoric acid) so there is certainly nothing innately impossible about making an effective wrinkle cream. (If you happen to invent one, do tell us...) Wnt (talk) 12:09, 7 October 2017 (UTC)[reply]

Cure for wrinkles: Gain weight as they would form, to fill the wrinkles in with fat. (The wrinkles would eventually show anyway, but hopefully you will die from obesity before this happens.) StuRat (talk) 03:13, 8 October 2017 (UTC) [reply]

Conductive fingernail decoration strip?

Is the metallic form of this nail strip (for decorating fingernails) liable to be conductive or is that a stupid thing to hope? I find myself in need of a conductive material that is adhesive, very narrow (~ 1mm) and aesthetically pleasing/decorative and it would be great if this was, even if the resistance is high for a conductor. --185.216.49.78 (talk) 17:01, 6 October 2017 (UTC)[reply]

Have you tried the fingernail tips for touch-screens? 209.149.113.5 (talk) 17:16, 6 October 2017 (UTC)[reply]

They also make gloves with those built in. I own a pair. StuRat (talk) 17:20, 6 October 2017 (UTC)[reply]

Very high impedance. Too high to power LEDs etc. Andy Dingley (talk) 17:24, 6 October 2017 (UTC)[reply]

No, it's a plastic (often polyester) with an aluminium metallisation deposited onto it. As the metallisation is so thin, resistance is high.

You might find conductive thread to be more useful. Also kitchen aluminium foil can be used like this, so long as you glue it down. I usually stick it to double sided tape, with the backing tape still in place, then guillotine that into narrow strips. Copper is better than aluminium for some tasks, as the oxide layer is less troublesome. Andy Dingley (talk) 17:24, 6 October 2017 (UTC)[reply]

It's not impossible that it's conductive enough for your purpose. But I wouldn't bet on it. I suppose for 0.99 you don't have much to lose, except your time, but I think you'll be frustrated.

Alternatives are conductive ink, copper tape, or conductive thread.

Good luck with your project. ApLundell (talk) 18:01, 6 October 2017 (UTC)[reply]

Carbon fibre is good for this though hard to find. I was given threads from a place selling fibreglass etc. for boat repairs.Polypipe Wrangler (talk) 23:14, 6 October 2017 (UTC)[reply]

Salmon

What would happen if a person ate only Salmon every day? Could they survive on that and for how long? — Preceding unsigned comment added by 2408:802A:9700:5083:A0A4:B4BE:DED0:D63F (talk) 18:15, 6 October 2017 (UTC)[reply]

Till they run out of salmon? ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:44, 6 October 2017 (UTC)[reply]

Conducting such an experiment would be unethical, and you haven't even told us if they are drinking water. See dehydration and ketoacidosis and ask us if you have a question answerable by references, not guesses. μηδείς (talk) 18:53, 6 October 2017 (UTC)[reply]

Salmon seems quite low in many common vitamins, and in manganese and calcium: [6]. Scurvy and rickets are two possibilities. StuRat (talk) 23:47, 6 October 2017 (UTC)[reply]

I do not believe an exclusive salmon died would result in scurvy. Salmon has indeed vitamin C.Hofhof (talk) 10:54, 7 October 2017 (UTC)[reply]

My source (linked above) says it's not a significant source of vitamin C. Do you have another which contradicts this ? StuRat (talk) 00:54, 8 October 2017 (UTC)[reply]

Another concern could be heavy metal accumulation (i.e. mercury) which is in higher quantity in large fish and in aquaculture-grown fish. —Paleo Neonate – 06:05, 7 October 2017 (UTC)[reply]

Wasn't there another recent speculative question about what would happen if someone tried to live on one specific food? And what was done with it, if anything? ←Baseball Bugs ^{What's up, Doc?} carrots→ 06:22, 7 October 2017 (UTC)[reply]

The question was closed too soon. Articles like rabbit starvation, No-carbohydrate diet or Inuit diet are about a similar issue. It's a fine question to me to ask what would happen if a human doesn't get enough of this or that nutrient.Hofhof (talk) 10:54, 7 October 2017 (UTC)[reply]

It was written by a drive-by, so it's unlikely he would even know if it was deleted. ←Baseball Bugs ^{What's up, Doc?} carrots→ 20:12, 7 October 2017 (UTC)[reply]

Those human-looking robots

You know each year they have those AI things where people make robots that are like people? Last I saw, they just stare off into space but talk like people. Can they now detect eyes and make eye contact and follow your eyes around? That would be well-spooky. Anna Frodesiak (talk) 23:59, 6 October 2017 (UTC)[reply]

This is nearly ten years ago https://www.youtube.com/watch?feature=player_embedded&v=hCsEFaInYlQ

For serious research, look at 'Kismet' at MIT Andy Dingley (talk) 00:07, 7 October 2017 (UTC)[reply]

Darn. YouTube is blocked in China. :( Would that have show the eyes thing? Anna Frodesiak (talk) 00:16, 7 October 2017 (UTC)[reply]

http://jarkman.co.uk/catalog/robots/theeyestheeyes.htm

http://www.jarkman.co.uk/catalog/robots/giantstaringeye.htm

Andy Dingley (talk) 00:43, 7 October 2017 (UTC)[reply]

That's a good start. Anna Frodesiak (talk) 00:56, 7 October 2017 (UTC)[reply]

This certainly is doable. We have other technologies that tracks eye movements to determine what the user wants. See eye tracking. The more subtle part would be in getting it to know when not to track eyes. For example, if I hand you a file and say "Here's the Johnson report" and you keep looking at my eyes instead of the report, I'd think there was something wrong with you. And then there's people on the autism spectrum, who often don't like people staring them in the eyes. This would upset them, especially if it wouldn't stop, when asked to do so. StuRat (talk) 00:25, 7 October 2017 (UTC)[reply]

That makes sense. Maybe it could track the nearest person, or the one emitting the most sound (the one talking). And that "Here's the Johnson report" thing reminds me of someone. Maybe he's a robot. I'm going to pour water on him to find out. :) Anna Frodesiak (talk) 00:31, 7 October 2017 (UTC)[reply]

Good thinking. That will also work if he's the Wicked Witch of the West, in disguise. :-) StuRat (talk) 00:36, 7 October 2017 (UTC) [reply]

Or one of those aliens from Signs (film). In fact, I think we should hire a hit man with a Super Soaker (we really do have an article on everything, don't we?) to hose down the top management of the WMF and see if they melt. You can't be too careful. --Guy Macon (talk) 01:24, 7 October 2017 (UTC)[reply]

Yes, water-soluble evil aliens without the sense to wear raincoats, on a planet where it rains regularly, really gave me a good laugh. StuRat (talk) 01:45, 7 October 2017 (UTC) [reply]

There could be multiple people talking. Also, whether they are looking at you should figure into whether you look at them, and also how well you know them, should. Then there are some cultures where servants aren't supposed to look their "masters" in the eyes, which would be important to know, if those robots are to be servants. StuRat (talk) 00:39, 7 October 2017 (UTC)[reply]

Well, for now, if it just stared at the nearest/loudest that would be pretty impressive, I think. Anna Frodesiak (talk) 00:55, 7 October 2017 (UTC)[reply]

Not just the loudest, that would mean always looking at Trump. :-) StuRat (talk) 01:49, 7 October 2017 (UTC) [reply]

Robots that Show Emotion is a relevant TED talk, as are the others on this play list [7].--Wikimedes (talk) 03:21, 8 October 2017 (UTC)[reply]

October 7

Are pumice stones a rational response to a callus?

I have a question that's only technically a medical question and I hope that you will indulge me on the basis that a) it's perhaps the least threatening of all medical anythings in the history of medicine and b) I resolved mine over a decade ago. When I was about 18-19, I somehow got a callus on my foot and when I asked my doctor about it, he said I should use a pumice stone on it. I complied for a while but it was uncomfortable and I just couldn't make sense of the advice. Given that a callus is the body's response to damage to the skin, how the hell is continually damaging the skin with a pumice stone an appropriate solution? In the end I over-ruled that stupid advice and left the callus alone and sure enough, in the absence of damaging stimuli, it went away. I just want to know whether the doctor's advice had any basis in sense or logic and have only just gotten around to asking. --185.216.49.78 (talk) 06:58, 7 October 2017 (UTC)[reply]

I don't know, but I just want to congratulate you on correctly spelling the noun as callus; so many people get it wrong. This is a regular paradigm: callus/callous, mucus/mucous, phosphorus/phosphorous — in each case, the version with -us is a noun; the version with -ous, an adjective. --Trovatore (talk) 07:03, 7 October 2017 (UTC) [reply]

As you implied, we can't (and won't) provide medical advice. We can link to articles such as callus and sources such as:

"Calluses and Corns: Using Pumice Stones-Topic Overview". WebMD. WebMD does not provide medical advice, diagnosis or treatment.

—2606:A000:4C0C:E200:6130:AA57:396F:78BA (talk) 07:10, 7 October 2017 (UTC)[reply]

I believe the idea is that, after the stimulus that caused the callus to grow is gone, the callus won't disappear on it's own, at least not quickly, so abrading it off can speed up the process. Since the pumice stone is only used on dead skin, it's not supposed to damage the living part of the skin, so shouldn't cause more to grow. But if you do continue to damage the living part, say by walking barefoot on rough ground, then, yes, I would expect the callus to continually regrow. Incidentally, this is just a form of exfoliation, but with a very thick layer of dead skin, rather than the thin layer of dead skin on the face. Calluses that get too thick can provide fertile ground for plantar warts, crack and cause more serious problems, therefore keeping them under control is important, so that it doesn't become a medical problem. (I use a pumice stone on my feet after taking a bath, when the skin is softer and easier to remove.) StuRat (talk) 21:18, 7 October 2017 (UTC)[reply]

Are you removing calluses, or merely dead skin? ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:01, 7 October 2017 (UTC)[reply]

Calluses are composed of dead skin, so yes to both. StuRat (talk) 22:07, 7 October 2017 (UTC)[reply]

If it's dead skin, I don't see why it would be a problem. Pedicurists do it all the time. My own doctor suggested it too. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:11, 7 October 2017 (UTC)[reply]

In some cases, calluses are helpful. Of course, the alternative is just to wear proper gear to offer the same protection as calluses, such as padded shoes or leather gloves. StuRat (talk) 23:10, 7 October 2017 (UTC)[reply]

I recall Pete Rose once talking about spring training and "getting the calluses going", as they would have faded during the off-season. The calluses enabled a player to improve his grip and were a better alternative than blisters. ←Baseball Bugs ^{What's up, Doc?} carrots→ 00:16, 8 October 2017 (UTC)[reply]

Yes, but batting gloves would be an even better option. StuRat (talk) 00:51, 8 October 2017 (UTC)[reply]

Except you can't feel the wood directly. But batting gloves (originally just golf gloves) were just starting to be used in Rose's day. They're in wide usage now. ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:24, 8 October 2017 (UTC)[reply]

A good set of batting gloves should give you a better feel for the bat than thick calluses would allow. StuRat (talk) 03:56, 8 October 2017 (UTC)[reply]

How many more base hits would Rose have gotten if he had been an early-adopter of batting glvoes? ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:08, 8 October 2017 (UTC)[reply]

Don't know, but I'm sure he would have taken bets on it. :-) StuRat (talk) 04:14, 8 October 2017 (UTC) [reply]

I googled the subject, and there are certainly a lot of products out there. One item (sorry, I failed to grab the link) warned against overuse of pumice... while promoting their own alternative product. It's fair to suppose that overuse of pumice could be counterproductive. But if you've got personal concerns, you should consult your physician. ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:10, 8 October 2017 (UTC)[reply]

Electric powering a vehicle through induction

Could vehicles - real or bumper cars - get their power from the road (floor) through induction? In the same way that a cell-phone gets loaded on a charge pad? Would that be less effective than getting power from electric wires strung above (as streetcars do)? --Hofhof (talk) 10:50, 7 October 2017 (UTC)[reply]

Linking relevant articles: Inductive charging and Conductive wireless charging.--B8-tome (talk) 12:32, 7 October 2017 (UTC)[reply]

Due to the power requirements and the ground clearance needed, and having to place the charging coils under every place cars could drive, that doesn't sound practical, to me. You'd need too high of a field strength, which might cause other problems (like things bursting into flames ?). However, it might be possible when parked, especially if the charger could be raised up closer to the car after parking. StuRat (talk) 22:11, 7 October 2017 (UTC)[reply]

For electric vehicles, buses, trains, MAGLEV, etc. resonant inductive coupling shows promise. 2606:A000:4C0C:E200:1DF7:C3BD:258E:E025 (talk) 22:19, 7 October 2017 (UTC)[reply]

"Chemtrails"

How can I convincingly prove to others that so-called "chemtrails" are only jet exhaust? I know I can't prove anything directly to the conspiratards themselves because they're too stupid to look at other evidence besides their own, but how can I prove this to gullible people who may be deceived by the conspiracy theories? 2601:646:8E01:7E0B:0:0:0:EA04 (talk) 12:08, 7 October 2017 (UTC)[reply]

Chemtrails are only jet exhaust. They are also a sinister geoengineering conspiracy looking to sacrifice 1000-4000 lives a year to hold back global warming by six months and make air flights cheaper. There is actually no contradiction... [8] Wnt (talk) 12:13, 7 October 2017 (UTC)[reply]

Your geoengineering link is a disambiguation page. Which one were you meaning to link to? CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 13:09, 7 October 2017 (UTC)[reply]

Presumably: Climate engineering 2606:A000:4C0C:E200:1DF7:C3BD:258E:E025 (talk) 20:38, 7 October 2017 (UTC)[reply]

You can't really fight a completely irrational view with rational arguments. However, this is a good resource explaining how the conspiracy came to life: [9]. B8-tome (talk) 12:23, 7 October 2017 (UTC)[reply]

"Reasoning will never make a Man correct an ill Opinion, which by Reasoning he never acquired". The answer is that people who believe that are lost as humans, and should be written off. Trying to correct them is just throwing good money after bad. Get new friends.--Jayron 32 20:49, 7 October 2017 (UTC)[reply]

This excellent summary [10] was in the Washington Post a few days ago. The comments section will provide some sense of how difficult it is to convince people that the notion is nonsense. Acroterion (talk) 22:08, 7 October 2017 (UTC)[reply]

You might mention cloud seeding, which is related. In both cases, if you seed dry air, nothing much happens, but if the relative humidity is high, it causes water to condense and form clouds. Do they not believe in cloud seeding ? StuRat (talk) 22:26, 7 October 2017 (UTC)[reply]

Why not re-attach the kidney?

I watched an episode of The Good Doctor. In that episode, there was a woman with a tumor. It was determined that it was impossible to remove the tumor because a (healthy) kidney was in the way. In the end, the decision was to remove the kidney to be able to access and remove the tumor, thereby saving the woman's life. The dilemma was whether or not to remove a healthy kidney. It was healthy (and healthy kidneys can be donated to other people) and there would not be a risk of rejection since it was being returned to the person it came from. Other than for the purposes of drama for the TV show, what would the ethical dilemma be and why not reattach it? 76.71.156.197 (talk) 22:22, 7 October 2017 (UTC)[reply]

It's still an involved operation, with associated risks, and apparently they thought it was not worth the risk to go from one kidney to two, since one kidney seems perfectly adequate for most people. On the other hand, if going from zero to one kidney, it is worth the risk, in many cases, as lacking any functioning kidneys can be a death sentence (dialysis can keep them alive for a few years). StuRat (talk) 22:30, 7 October 2017 (UTC)[reply]

@ StuRat. More than "a few years". I knew someone who was on dialysis for about 30 years and there has been a case of 39 years. Both these cases were about 20 years ago, I suspect the technique is even more reliable today. Richard Avery (talk) 07:39, 8 October 2017 (UTC)[reply]

October 8

FLAT EARTHER speaks the truth

This is the best argument I heard from a flat earther where every statement he made (with the exception of "the earth is flat") is the literal truth.

“If you watch the trajectory of the Space Shuttle, it does not goes straight up, it always goes in a curve and out to sea (I think they meant the Atlantic Ocean). The point is, they actually goes horizontal. The Space Shuttle goes horizontal. It does not goes any further up, it goes horizontal. This proves the earth is FLAT.” 110.22.20.252 (talk) 08:48, 8 October 2017 (UTC)[reply]