Wikipedia:Reference desk/Archives/Science/2016 July 10

= July 10 =

sleeping on trains
Moved to Reference_desk/Miscellaneous

Are transparent solar panels bogus?
Are transparent solar panels even possible? Can a photon go through a panel and generate electricity without being absorbed? The presumptive inventor of these also claims that his transparent solar cell coatings can generate 50 times more energy than conventional solar panels. This makes it all look even more suspect. Are conventional solar panel so inefficient that their output can be multiplied by 50? --Llaanngg (talk) 11:42, 10 July 2016 (UTC)


 * A photon going through a solar panel unabsorbed and still generating electricity is a violation of the law of conservation of energy and therefore bogus. It is however possible to create solar panels that absorb part of the incoming photons for electricity and let another part through, so that's a solar panel producing less electricity than a normal panel, at the same time acting as tinted glass. A normal solar panel is not so inefficient that its output can be multiplied by 50. Maybe the inventor means that using these panels you can cover 50 times more surface area because they can be used on places where one would normally use windows? PiusImpavidus (talk) 12:31, 10 July 2016 (UTC)


 * We have an article on Ubiquitous Energy, an American solar energy startup ... that designs transparent solar technology to absorb ultraviolet and near infrared light (NIR) (wavelength span of λ= 650– 850 nm) while transmitting visible light through its medium called ClearView PowerTM. From § Future_Goals: The current development of the solar cells is transmitting approximately 70% of visible light and has a power conversion of approximately 2%. Researchers think that realistically they should be able to reach over 12% power conversion efficiency while still transmitting visible light with there are theoretical limits above 20%. -- ToE 12:57, 10 July 2016 (UTC)
 * See also Solar cell efficiency which states that efficiencies vary from 6% for amorphous silicon-based solar cells to 44.0% with multiple-junction production cells and 44.4% with multiple dies assembled into a hybrid package. -- ToE 13:02, 10 July 2016 (UTC)


 * They're certainly possible, but you have to be careful with terminology. The Sun is broad band radiation, eyes are a narrow band, and infra red (heating the inside of a building) can be a downright nuisance in many sunny climates. So a panel with passes visible light and absorbs UV or IR would be very useful, and credible. Andy Dingley (talk) 13:45, 10 July 2016 (UTC)
 * My credibility falters at the notion of a passive panel that does not reflect but absorbs IR without heating the inside of a building, because that would surely require some kind of Heat engine in conjunction with a colder source. AllBestFaith (talk) 15:32, 10 July 2016 (UTC)


 * The organic salts absorb UV and infrared, and emit infrared — processes that occur outside of the visible spectrum, so that it appears transparent.
 * --2606:A000:4C0C:E200:D0C4:DF9D:2B6A:49F5 (talk) 16:32, 10 July 2016 (UTC)


 * Their goal of using it to power mobile devices seems unrealistic. If it only captures 2% of the IR and UV energy hitting the device, that wouldn't be enough to power the display and make it bright enough to view in sunlight.  Perhaps it could charge the battery while sitting in the sunlight, but would people really want to leave their devices sitting out, where they could be damaged or stolen, instead of safe in their pockets ?  Of course, there could be safe spots inside to sit it in the sunlight, like in a window sill, but then the device could just as well be plugged in.


 * Digital signage has similar problems with power produced versus power consumed, but it might work to charge a battery and have the sign only flash a message when a vehicle passes, on infrequently used roads.


 * The use on building windows could be feasible, if the cost is low and if they last long enough. If they fail in a few years, like traditional solar cells, then you would need to replace the windows, and that's probably not going to happen. StuRat (talk) 16:58, 10 July 2016 (UTC)


 * When you're hiking it'd be nice to have any extra battery life at all just by holding it in a non-shady grip. I once wandered for miles cause I had to minimize sunlight-level screen brightness (it was now dark) at 0% battery then scramble to learn the map between me and the train station (it died before I memorized far enough ahead obviously). I didn't know it turned on accidentally for hours cause I intentionally memorized as far ahead as possible to save battery life. Sagittarian Milky Way (talk) 20:07, 10 July 2016 (UTC)


 * I suggest a back-up battery, either a 2nd battery for the phone or an external one with a USB charger. And a plain old paper map would be useful, too.  No GPS, to be sure, but it can get you home once you find a landmark, like a stream. StuRat (talk) 20:33, 10 July 2016 (UTC)


 * Paper map, what's that? Sagittarian Milky Way (talk) 00:53, 11 July 2016 (UTC)


 * 2060:


 * Paper? That's the kind of screen that can't turn off, right grandpa? Well, I can see how that might be useful. My friend told me paper screens can only show one thing, is that true?


 * Yes, boy. When I was your age you couldn't just ask the map for cnn.com or homework help or movies to wank to, you couldn't even be friends with it, they had these gigantic newspaper screens of news which never updated. They were at least hours out of date and you had to keep paying your allowance each day to get new ones.


 * Holy shit!


 * That's why I read my parents' papers after they were done, if I bought them myself I'd hardly have any chip left. Er, green rectangles that looked like this. , We didn't use chip yet.


 * You sold things for THAT?


 * Er, you'd never understand, you'd think we were retarded. Sagittarian Milky Way (talk) 00:53, 11 July 2016 (UTC)


 * Paper has other advantages. For example, although it might be tempting to try, in an emergency you can't wipe your butt with a cell phone. :-) StuRat (talk) 03:22, 11 July 2016 (UTC)


 * And if you're ever trapped long on a desert isle with only a lifetime supply of canned crackers/vitamins/bottled water a few $10,000 bills and no clothes, well, the option's there.. daring you.. Sagittarian Milky Way (talk) 20:21, 11 July 2016 (UTC)


 * What country has $10,000 bills? Anyway, money is washable, so feel free to wipe your butt with it. The central bank also has the obligation to replace damaged bills, as long as it can be assessed that you have 50% or more of the bill. Hofhof (talk) 10:37, 14 July 2016 (UTC)

Mars today and yestreen
Mars has a thin but active atmosphere. We see dust storms from Earth and we have footage of willy-willys from rovers. Despite the passage of at least 3.8 billion years- and the mind boggles at that span of time- we can see abundant evidence of the earliest Martian geological history. Why is this possible? Why have these features not been obscured by a uniform shroud of aeolian deposits? On Earth wind-swept deposits have all but obscured many of the hard rock features that underlie the Sahara in only a few thousand years. Little water is involved here. Any thoughts? Captainbeefart (talk) 14:43, 11 July 2016 (UTC)


 * I think you are mistaken in stating that water isn't involved in the formation of sand dunes in the Sahara, etc. The initial breakdown of rock, such as quartz, into sand particles is largely dependent on water erosion.  That sand then is deposited on beaches, which, with changing climates and moving shore lines, later become sand dunes.  So, much of that rock on Mars was never broken down by water into sand, therefore Mars lacks the thick layer of sand you see in places on Earth. StuRat (talk) 17:03, 10 July 2016 (UTC)


 * See Aeolian_processes. Which beaches would contribute to the sand dunes of the Gobi Desert? Mikenorton (talk) 19:40, 10 July 2016 (UTC)


 * If you go back far enough, virtually all land was underwater at some point. I believe the uplift of the Gobi happened when the Indian plate slammed into the Eurasian plate, so it would have been some time before that (10 million years ago ?).  Also I should mention that water erosion happens even in spots with far less water, such as the freeze/frost cycle cracking and eventually breaking down boulders.  Mars may not even have enough water for this, however.StuRat (talk) 20:38, 10 July 2016 (UTC)


 * Geological activity is still taking place on Mars, see Mars. New streaks appear frequently on steep slopes of craters, troughs, and valleys. Images in 2009 from the Mars Reconnaissance Orbiter showed evidence of an avalanche from a 700 m high cliff. AllBestFaith (talk) 17:07, 10 July 2016 (UTC)


 * (Willy willy: Austrahlian for dust devil) Sagittarian Milky Way (talk) 19:15, 10 July 2016 (UTC)


 * The windblown dust will be taken out of circulation at various places. Some will be consolidated to stone.  The Mars Rovers found rock made from cemented dust.  It may become cemented by salts drying out from fluids or perhaps by ice.  High pressure or high heat could do it too, (stick grains together), but are there places on Mars where dust could be buried many kilometers deep? Graeme Bartlett (talk) 23:58, 10 July 2016 (UTC)


 * Maybe at the bottom of deep craters ? StuRat (talk) 22:13, 11 July 2016 (UTC)


 * List of tectonic plates lists a number of blocks that date back, not quite 3.8 billion years, but nearly as long. Despite much more water and much more air on Earth to do erosion, and a much stronger plate tectonics to resurface the crust entirely.  So it seems like little surprise that there would be some pristine crust on Mars.  Also remember that waves of sand move slowly across hard rock - if you ever play around looking at the Sahara and other sandy deserts in satellite view, you see plenty of hard rock shining through in places where the waves are shallow.  The sand ultimately wants to move down, so whatever is up tends not to stay covered. Wnt (talk) 19:02, 12 July 2016 (UTC)

Ionic strength fraction
I've encountered in some papers, although undefined explicitly, the concept of ionic strength fraction denoted y for a mixture of at least 2 salts in aqueous solutions. What is the exact definition of this quantity?--82.137.14.64 (talk) 18:43, 10 July 2016 (UTC)
 * The article already mentioned cites a research article here. These articles explain that an electrolyte's ionic strength is half of the total obtained by multiplying the molality (the amount of substance per unit mass of solvent) of each ion by its valence squared. AllBestFaith (talk) 22:36, 10 July 2016 (UTC)

Miracle Mineral Supplement
If Miracle Mineral Supplement is a quack cure, which it is, why do so many people seem to be testifying its effectiveness? Mage Resu (talk) 23:40, 10 July 2016 (UTC)
 * Confirmation bias? 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 23:45, 10 July 2016 (UTC)
 * People believe all sorts of silly things. I think I've read that almost half of Harvard graduates (!) believe the seasons happen because Earth is closest to the sun in summer and farthest in winter. Shock Brigade Harvester Boris (talk) 23:52, 10 July 2016 (UTC)
 * It also seems that the more I argue with them the STRONGER their opinion gets! Why? Mage Resu (talk) 23:55, 10 July 2016 (UTC)
 * Humans tend to do that. You may find this interesting. Shock Brigade Harvester Boris (talk) 00:01, 11 July 2016 (UTC)
 * Thanks! Mage Resu (talk) 00:07, 11 July 2016 (UTC)
 * And why is Google refusing to take down this video? Mage Resu (talk) 00:04, 11 July 2016 (UTC)
 * Google's legal protection from various forms of lawsuits is centered on their being a passive distributor of content without editorial control. (The Wikimedia Foundation's legal status is similar.) They can take down things that they are legally obligated to remove, such as copyright violations. But if they take down things simply because they're stupid and wrong, they are exercising editorial judgment and therefore put their legal protections in jeopardy. Shock Brigade Harvester Boris (talk) 00:12, 11 July 2016 (UTC)
 * Um... That video is promoting the dangerous and illegal use of MMS to "cure" autism. Yes, illegal! Sellers of MMS have been prosecuted, according to the Wikipedia article! Mage Resu (talk) 00:21, 11 July 2016 (UTC)
 * You seem to be confused by the meaning of illegal. Some specific actions have either resulted in settlements or judgements of fraudulence, which are civil torts, and not crimes.  There would have to be a law banning the production, possession, or distribution of this stuff for it to be  ILLEGAL  under common law. μηδείς (talk) 02:51, 11 July 2016 (UTC)
 * I actually have a personal interest in this stuff, I've even had Jim Humble himself personally message me after "debating" with some MMS supported who tried to edit our article here. If you start digging, this is a VERY deep rabbit hole, like a lot of "alternative medicine". Answers to these questions are not "straight forward" and easy to answer, there are many confounding factors and different answers for different people. Why are there anecdotes? Placebo effect accounts for some, Choice-supportive bias accounts for some, Selection bias plays into it (you don't hear from people who it didn't work for). I find it an extremely fascinating topic. If you are genuinely interested in this topic generally, rather than MMS specifically, i would recommend you read something like Trick Or Treatment specifically about medicine, or Bad science about science in general. Vespine (talk) 01:56, 11 July 2016 (UTC)
 * Very loosely, critical thinking is not innate to humans, you have to LEARN how to be a good critical thinker and most people do not learn how to be good critical thinkers. This is why almost every tabloid magazine still has an astrology column. Vespine (talk) 01:58, 11 July 2016 (UTC)
 * as to why people get away with seemingly "illegal activity", well Jim Humble lives in the Dominican republic and a lot of these videos are produced and posted by people who do not actually "sell" MMS, so what do you charge them with? And chasing and prosecuting these people takes a lot of time and resources and expensive lawyers so who pays for it? There have been a few "high profile" cases where people have been prosecuted, but chasing every small operator or promoter is beyond the resources of any publicly funded organization, most of those have bigger fish to fry, that's the answer I've received every time I've tried to report a scam charity or snake oil salesman to some authorities. Vespine (talk) 02:02, 11 July 2016 (UTC)


 * Also, some people are willing to say anything to get onto TV, into web videos, etc. StuRat (talk) 02:17, 11 July 2016 (UTC)


 * http://www.dailymotion.com/video/x1z4iyq_e07-the-power-of-the-placebo_tv Count Iblis (talk) 03:39, 11 July 2016 (UTC)


 * The main reason why you can't ban scientifically "wrong" information is that its freedom is required for the opposing position to be falsifiable. The moment it becomes impossible to say that vaccines cause autism, in that instant it is no longer scientifically possible to prove that they do not.  Now I suppose you could try to argue that this is not true for a ban only in certain places specifically designed for children and the feeble-minded, such as television, since the truth could be argued elsewhere.  Nonetheless, to do so in any way would create a caste system as tangible as SIPRNet, where from the perspective of the lower caste, the statements of the upper caste are self-serving and unreliable, and therefore the arguments they make are not falsifiable for them.  Which means that precisely the group you want protected from fallacious thinking no longer possesses a defense against it.  History is full of authoritative medical statements endorsed by all the highest authorities that were complete bullshit - for example, using margarine instead of butter for its safety, or hormone replacement therapy.  So the paranoia of the lower caste here is well-warranted even when there isn't a formal prohibition. Wnt (talk) 19:31, 12 July 2016 (UTC)


 * Um... Injecting bleach into children's anal canals, which is exactly what the videos are promoting, constitutes child abuse! It's not just scientifically inaccurate! It's actually harmful and illegal! Mage Resu (talk) 02:55, 14 July 2016 (UTC)


 * And Wikipedia has removed dangerous pseudoscientific nonsense from their articles. See the MMS Wikipedia page history! YouTube has the right to do the same! Anyone can see that this is not only quackery but child abuse! The reason that the sellers haven't been prosecuted is that they have made every possible effort to avoid it! The first amendment does not force YouTube to host whatever some idiot posts on it! It only says that the government cannot deny people the right to free speech! Mage Resu (talk) 19:14, 14 July 2016 (UTC)
 * The problem is where one should draw the line. If you feed your child too many big macs then that's harmful too. If new research proves this view on a good diet right, then that means that most of what we eat is harmful to our health, so much so that irreversible damage has already been done. But do you want the government to make most of the foods you enjoy eating illegal, assuming that it is indeed proven to be harmful? Count Iblis (talk) 21:06, 14 July 2016 (UTC)
 * See this link. Mage Resu (talk) 21:45, 14 July 2016 (UTC)
 * Also, unlike junk food, MMS is acutely toxic! Mage Resu (talk) 22:42, 14 July 2016 (UTC)
 * There are several problems with turning to YouTube for censorship. To begin with, if they are actually effective at playing God with the content, deleting whatever is unwise, the more that viewers may be lulled into thinking that if YouTube carries a video it must be safe.  Then there's the issue that they are a private company and can't be trusted to remain universally impartial and caring in relation to every sort of scam.  Then there's the issue that they are, or should be, just one company and people looking for the video who find it deleted there will just go wherever it isn't censored.  We are better off simply letting people post whatever they want, and teaching viewers not to believe everything they see. Wnt (talk) 23:08, 14 July 2016 (UTC)
 * I'm pretty sure there are LAWS against shooting BLEACH up a kid's ASS!!! Failure to remove the video is assisting scammers in promoting illegal activity! Mage Resu (talk) 00:50, 15 July 2016 (UTC)
 * There are laws against cutting people's heads off, but that doesn't mean that YouTube should censor video from scenic downtown Raqqa. There are a lot of people wandering around out there who need to learn the difference between a crime and a picture of a crime. Wnt (talk) 02:03, 15 July 2016 (UTC)
 * They're not just displaying illegal activity! They're promoting it! There's a difference! Mage Resu (talk) 02:18, 15 July 2016 (UTC)
 * So should YouTube censor videos where people talk about growing pot, and movies where the characters do lines of coke? A few recreational drugs are actually worse than this bleach and acid mix, but I don't want the company deciding what I can watch. Wnt (talk) 02:35, 15 July 2016 (UTC)
 * That is a completely different scenario! The only victims of these recreational drugs are the users themselves! This woman is encouraging parents to shove it up their kid's ass! The kid can't give consent! Mage Resu (talk) 02:40, 15 July 2016 (UTC)


 * Any time you see the word "miracle" mentioned by the media or an advertiser, feel free to take it with as much salt as you like. A miracle is something that has been observed to occur, but which appears to defy rational or scientific explanation.  A little boy goes missing; they search for him, and they find him.  Is that a miracle?  Well, hardly.  The media would have us think it is, though.  A certain supplement may have health benefits, but what about that is miraculous?  If they're saying "We have no idea how it works, but it works", then they also have no idea of any potential side-effects, so it needs to be given a very wide berth until and unless it is demiraclised. --   Jack of Oz   [pleasantries]  22:02, 14 July 2016 (UTC)
 * That argument works for rational thinkers only! Desperate and naïve parents will call you a "Big Pharma troll" if you tell them that! Mage Resu (talk) 22:10, 14 July 2016 (UTC)