Wikipedia:Reference desk/Archives/Science/2010 March 1

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March 1[edit]

Scientocracy[edit]

Scientocracy is listed on the "Wikipedia:Requested articles/Social sciences" page at http://en.wikipedia.org/wiki/Wikipedia:Requested_articles/Social_sciences

I have written a draft of an article about scientocracy. See http://en.wikipedia.org/wiki/User:JasonCupertino/Sandbox

Is that draft ready to be posted in Wikipedia's main space as a new article? JasonCupertino (talk) 00:17, 1 March 2010 (UTC)

It could use a section of the history of usage of the word. When did people first start using it? How many are using it now? etc. --Tango (talk) 00:23, 1 March 2010 (UTC)
The Ref Desk isn't really the place for this sort of question - on the other hand, I don't really know where it _should_ be posted. WP:DRAW, or WT:WikiProject Sociology perhaps? Anyway, the article looks quite reasonable to me - I would probably remove the first paragraph, especially the part about Ghits, and just start "Scientocracy describes the practice of basing public policies on science." A citation for the first paragraph of the "Scientocracy as a form of government" section would also help - which of the various authors you cite has this opinion? If it's derived from more than one author, add a reference to the appropriate author to the corresponding sentence - if it's just one of them, add the reference to the end of the paragraph. If it's your own opinion, however, it shouldn't be in the article, per WP:OR. However, these are just minor issues - I'm sure it would survive an AfD if it were to go live now. If you can't move it yourself, add the {{move draft}} to the top of the article. Tevildo (talk) 00:44, 1 March 2010 (UTC)
I strongly disagree with User:Tango. Your first line is "Scientocracy is a neologism" - which is an immediate red-flag. Have you read WP:NEO? If not - please do so immediately - especially the section "Articles on neologisms"! You need to be sure that this isn't an article about the word (Wikipedia isn't a dictionary) - so dump the entire first paragraph because that, right there, would be enough to cause the article to be deleted. It needs to be strictly about what scientocracy is - not about the word itself. Hence adding history of the usage of the word would be a very bad thing. The very last thing you want to emphasise is the newness of the word - you have to stick to the concept behind it - and kinda reluctantly use this admitted neologism to describe that concept. That said - without the first paragraph, it's not a bad article and I'd post it into main-space and see what happens when it's exposed to other editors. SteveBaker (talk) 01:14, 1 March 2010 (UTC)
Replace "word" in my comment with "concept" and the point stands. The difference between a word and the concept described by that word is largely meaningless. --Tango (talk) 01:19, 1 March 2010 (UTC)
For where it should be posted, I would say, besides WP:DRAW and any applicable WikiProjects like Tango said, WP:HD and WP:RfF are good for things like this. —Akrabbimtalk 01:21, 1 March 2010 (UTC)
That was Tevildo, not me. --Tango (talk) 02:32, 1 March 2010 (UTC)
For what it's worth, I'd vote against it on AfD as a neologism. Comet Tuttle (talk) 01:25, 1 March 2010 (UTC)
The execrable Pomosexual survived AfD ([1]) on a far flimsier footing; however, past history is no guide in that particular area of the project. Tevildo (talk) 01:45, 1 March 2010 (UTC)
You know, I'm convinced I !voted against that - why else would I know about it? - but my opinion isn't in the AfD. Was there a second one, or is this a glitch in the Matrix? Tevildo (talk) 02:23, 1 March 2010 (UTC)
The general requirement for inclusion in Wikipedia is the existence of good sources. This article seems to satisfy that. Being new doesn't count against it - plenty of things get articles as soon as they come into existence. --Tango (talk) 02:36, 1 March 2010 (UTC)
Are you saying that "Scientocracy" exists? It does not exist. Comet Tuttle (talk) 04:01, 1 March 2010 (UTC)
That depends on your definition of "exists". As an abstract concept, it definitely exists. --Tango (talk) 05:02, 1 March 2010 (UTC)
As an article about a word - it's newness definitely counts against it (per WP:NEO) - as a concept, newness is not necessarily an obstacle. As presented to us, this article would be about the word and that would likely get AfD'ed into oblivion in short order. However, without the first paragraph, this would be an article about a concept - with an unfortunate choice of a neologism for a name - which ought to pass muster. SteveBaker (talk) 13:03, 1 March 2010 (UTC)
The concept may sound appealing but it's so poorly defined, even with the references, that there's just no way. "Caninocracy" gets google hits and is appealing to some people and should not be a Wikipedia article about it. Comet Tuttle (talk) 15:26, 2 March 2010 (UTC)

Tango: I added a section that presents what I think may be the first use of "scientocracy". I also added a reference to an online Oxford English Dictionary search yielding "no results". But I should probably delete those things if I am going to eliminate the reference to scientocracy being a neologism.

Thank you one and all for taking the time to evaluate my draft of scientocracy. I will keep working on it with your comments in mind. JasonCupertino (talk) 06:03, 1 March 2010 (UTC)

The word scientocracy is not in Wikitionary. You may try to get it added there. Here is some etymology extracted from [2]:
science c.1300, "knowledge (of something) acquired by study," also "a particular branch of knowledge," from O.Fr. science, from L. scientia "knowledge," from sciens (gen. scientis), prp. of scire "to know," probably originally "to separate one thing from another, to distinguish," related to scindere "to cut, divide," from PIE base *skei- (cf. Gk. skhizein "to split, rend, cleave," Goth. skaidan, O.E. sceadan "to divide, separate;"
-cracy comb. element forming nouns meaning "rule or government by," from Fr. -cratie or M.L. -cratia, from Gk. -kratia "power, might; rule, sway; power over; a power, authority," from kratos "strength," from PIE *kratus "power, strength". The connective -o- has come to be viewed as part of it. Productive in English from c.1800. Cuddlyable3 (talk) 10:56, 1 March 2010 (UTC)
If it is a "new" neologism, then it probably should go in Wiktionary's list of "protologisms". It is unlikely to merit an entry in the dictionary unless you can cite permanently recorded media, conveying meaning, in at least three independent instances spanning at least a year (or use in a refereed academic journal). Just a mention or a definition of the word is not sufficient to merit inclusion. Dbfirs 12:32, 1 March 2010 (UTC)
... (later) ... actually, you do seem to have mentioned the required citations in your article, so perhaps the word is not so "new"? Dbfirs 12:38, 1 March 2010 (UTC)

nuclear versus fossil[edit]

France is the world leader in nuclear power. Cuddlyable3 (talk) 10:37, 1 March 2010 (UTC) ... but only if you are considering percentage of their total electricity generation, and not total number of plants or amount of electricity produced. If you consider the latter to be important, then the U.S. is the (reluctant) leader. --Mr.98 (talk) 12:43, 1 March 2010 (UTC)

How many nuclear reactors would be required to replace all of the fossil fuel now being used by the world? 71.100.5.197 (talk) 07:56, 1 March 2010 (UTC)

This says there are 436 reactors in the world, and the same website claims they provide 15% of the world's power. So, you'd need 6.66 times more reactors, or 2907 reactors in total. Of course, that assumes that the website is accurate, and that all reactors supply the same amount of energy (which they don't.) Vimescarrot (talk) 09:51, 1 March 2010 (UTC)
It wouldn't be 6.6 times even under those assumptions; fossil fuels do not account for the entire remainder of 85%. Someguy1221 (talk) 09:56, 1 March 2010 (UTC)
According to our nuclear power article, nuclear power supplies approximately 15% of the world's electrciity, but only about 2% of the world's energy. According to fossil fuel the breakdown of primary energy consumption (not sure how this is defined) is 86.4% fossil fuels, 8.5% nuclear, 6.3% hydroelectric, 0.9% other (hmmm ... those figures add up to 102.1% !). Gandalf61 (talk) 10:34, 1 March 2010 (UTC)
To eliminate all of the fossil fuels, you'd also have to find ways of not using coke in blast furnaces and in all sorts of other industrial settings, replacing every ship, diesel train, car, motorbike, bus and truck with either all-electric or hydrogen powered vehicles that could ultimately get their power from nuclear sources. Some forms of transport (such as aircraft) are not easily converted - I don't believe there is a single powered aircraft anywhere in the world that does not run on fossil fuels - and I don't see a whole lot of research being done to fix that. Some of those industrial processes would also be very difficult to replace with electrical processes. But if we believe Gandalf61's figures, we obviously need to increase our nuclear power base by a factor of 10. So we'd need about 4,400 reactors. I suspect that's an under-estimate because there are inefficiencies in using electricity to charge batteries and make hydrogen that are not accounted for in the energy extracted from fossil fuels directly. (If a car is currently rated at requiring X joules of energy per mile - then it will need X joules of hydrogen power to do the same thing - but it would take X+Y joules of nuclear-generated electricity to make that hydrogen - where Y is the inefficiency in the process.)
The obvious problem with doing this are that the capital investment to replace all of those users of fossil fuels with electric power would be spectacular - not least because nuclear power plants are 20 to 30% more expensive over their lifetime than coal plants...but WAY more expensive to construct in the first place.
Some critics of nuclear power would also claim that there is a problem with nuclear plants doing something called "load following" - when there is a major sporting event on TV, electricity consumption spikes when it's over as everyone goes off to cook food or whatever. The claim is that you can't ramp up power from your nuclear plants fast enough to meet that demand. However, France gets 80% of its power from nuclear and it manages this just fine - so there must be ways to fix that.
Another issue is that there are many places in the world with unstable governments and low technical expertise where nuclear power plants would be unsafe to run - and a dangerous source of fissionable products for nuclear weapons. That would be a serious consideration.
Finally, if electricity were to jump from being perhaps 20% of our energy supply to 90% or more, we'd need much more transmission line capability around the world. This kind of additional infrastructure doesn't come cheap.
Certainly we're going to need to dramatically increase our nuclear power base if we're going to duck this global warming catastrophy - but to make this work, we need a greater diversity of sources - and we need to cut consumption fairly dramatically too. It's much cheaper to use less than to generate more. Consider how many 20mpg cars there are on our roads and note that we have 40mpg cars (my car does 42) without resorting to hybrid technology or even suffering poor performance. If we pushed the technology, we could certainly get to 60mpg. If we did that then we'd drop the amount of energy consumed by cars by a factor of three - which would save about 16 billion gallons of gasoline a year...representing several hundred nuclear power plants. That kind of thing is a much better short-term fix than a massive nuclear build-out program.
SteveBaker (talk) 12:58, 1 March 2010 (UTC)
Comment - nuclear power does perform better at load following than coal, on account of nuclear control rod and associated throttling technology. Nimur (talk) 23:51, 1 March 2010 (UTC)
Indeed, however I believe there is a minimum energy production you need to maintain or it all goes horribly wrong. Shutting down a nuclear reactor is a lot of work, as is starting it back up again. Between that minimum and whatever the maximum is, you can vary things reasonably easily, yes. --Tango (talk) 01:35, 2 March 2010 (UTC)
I saw a talk by Richard Garwin a few years back that advocated thinking about these technologies as "wedges" in an overall pie of things to do, if you wanted to avoid global warming issues. One is increased nuclear. One is increased renewables. One is increased efficiency. One is increased capping and scrubbing. Maybe there were a few more, as well. But the emphasis was on the idea that you aren't going to have just one of these ideas actually do all of the work needed—and that focusing on trying to get one massive program adopted was surely going to fail, whereas doing a few things modestly, but simultaneously, would probably get a lot done. (Personally, I'm dubious that we can even get modest things done.) --Mr.98 (talk) 14:16, 1 March 2010 (UTC)
A side note... model airplane hobbyists have since the days of floppy, hard drive and CD/DVD motors experimented with "Y" and Delta windings to achieve higher RPM or higher torque. Several manufacturers have made still further improvements where shrouded props provide models with very high speed. Battery technology is a problem when scaled but promise lies in ultra-capacitors so like nuclear fusion capacitor powered airplanes might not be that far away. Next question I'll make reference to those technologies rather than just fission and lower energy density alcohol fuel as now. 71.100.5.197 (talk) 13:49, 1 March 2010 (UTC)
Even the most ambitious real-world (e.g. non-internet) boosters of nuclear fusion don't see it as contributing much if anything to the total electrical generation for another 40 years at a minimum. It is not really on the table in a real-world energy calculation. --Mr.98 (talk) 14:16, 1 March 2010 (UTC)
There is at least one manned solar plane: Solar Impulse[3]. Unmanned ones, too: QinetiQ Zephyr and NASA Pathfinder. Rmhermen (talk) 14:29, 1 March 2010 (UTC)
Well, there are some electrically powered gliders too - they pull the plane up to enough altitude to pick up thermals and such - but there isn't enough power to do useful work. SteveBaker (talk) 02:27, 2 March 2010 (UTC)
Yes, but there is no way those solar planes could replace current planes. They just don't have the lifting power to transport passengers or cargo. --Tango (talk) 20:50, 1 March 2010 (UTC)
Indeed, fusion is a long way off. Small scale fusion in individual devices is even further off. --Tango (talk) 20:50, 1 March 2010 (UTC)
The hope is that if we can build enough fission plants to keep us out of disaster - then maybe fusion can take over before we run out of dark places to hide the crap that the fission plants produce. But neither technology will fix the problem alone. We need boatloads of windmills and lots and lots of trimming of demand. SteveBaker (talk) 02:27, 2 March 2010 (UTC)
Or we can reprocess the crap and reuse it in breeder reactors, which will allow us to use fission for the next 3000 years without generating any significant nuclear waste. Clear skies 24.23.197.43 (talk) 06:42, 2 March 2010 (UTC)
That's a little naive. You should read Radioactive waste. Sure, you can reprocess spent fuel rods - but that's not the only radioactive waste these plants produce. Things like worn out equipment that's been exposed to radiation and end-of-life parts of the reactor itself produce low and medium level radioactive waste that cannot be re-used and yet is not safe to dispose of in ordinary ways. The casings of reprocessed fuel rods are highly radioactive and cannot be re-used when the rods are reprocessed. I read somewhere (sorry, I forget where) that just disposing of overalls that workers had worn inside the plant caused a significant waste storage/disposal problem at several US reactors (there is passing mention of this in the Radioactive waste article). SteveBaker (talk) 13:20, 2 March 2010 (UTC)
Not wanting to pick a technical fight, but I am pretty sure that reprocessing does significantly reduce the mass and volume of highly radioactive materials needed for long-term repositories. The problem with waste storage is mostly political, in any case—a problem of a lot of people against having waste sites anywhere, and a political system which requires waste storage sites to try and meet really fairly crazy and unscientific criteria (like being able to prevent basically any deaths over the course of thousands and thousands of years). If we were able (which in the US, we aren't) to politically treat nuclear waste the way we do with other, persistent and nasty industrial wastes (many of which are never going to decay into something less harmful), we'd be able to find an acceptable solution (one which would indeed probably involve a small number of people sacrificing something for the greater good, e.g. being relocated permanently). But we can't, and so we probably won't. But reprocessing would reduce a lot of the nasty stuff (and also make more use out of the existing uranium). The spent fuel rods are definitely the worst kind of radioactivity that the plants produce—fission products, transuranics, etc. Low-level nuclear waste (the overalls) requires its own procedures but it is orders of magnitude less dangerous than the high-level stuff. --Mr.98 (talk) 18:39, 3 March 2010 (UTC)
BTW, with enough hydroelectric dams (especially hydroelectric storage), we won't even need no stinkin' windmills, which aren't cost-effective anyway. 24.23.197.43 (talk) 06:51, 2 March 2010 (UTC)
Dams are being removed rather than created in the US because they aren't a good long term solution in most places. Aside from the damage they do to wildlife on these rivers, they also silt up over time and become gradually less effective. They are often horribly difficult and costly to remove - and when you figure that into the lifetime cost of them - they come out much less cost-effective than had previously been assumed. I really can't agree with you about the cost-effectiveness of wind power - what you are saying simply isn't backed up by science. There have been many studies on this - some find it to be marginally cheaper than coal and gas plants - others marginally higher (much depends on the projected lifespan of the equipment - which is something of an unknown right now). Probably the most comprehensive study said that cost per unit of energy for wind was estimated at $55.80 per MW·h, coal at $53.10/MW·h and natural gas at $52.50. (These numbers are quoted, with references in Wind_power#Economics_and_feasibility). If/when we get a proper accounting of the 'costs' of CO2 pollution and any kind of carbon tax or cap & trade system - then windmills will turn out to be highly economical - which is why so many of them are being built right now. However, they aren't good at load-following because you don't always have enough wind - and there aren't enough suitable places to build them in many parts of the world. Hence nuclear is likely to be a good part of the solution. SteveBaker (talk) 13:20, 2 March 2010 (UTC)
When I mentioned dams, what I meant was that they are uniquely useful for energy storage: you can just use excess electrical power at off-peak times to pump the water upstream, and then use the stored hydraulic power to generate electricity at peak times. You can't do that with any other kind of power plant, and definitely not with a windmill. And speaking of windmills, do the numbers you quoted include the capital cost of building them, or just the operating cost? 24.23.197.43 (talk) 05:31, 3 March 2010 (UTC)
I just looked at the references in Wind_power#Economics_and_feasibility; the main source for the figures you gave is a study done under the auspices of the BWEA, which may have a vested interest in promoting wind power. Do you know any independent studies that conclude wind power is economically competitive and sufficient to meet US electricity production needs? 24.23.197.43 (talk) 05:43, 3 March 2010 (UTC)
There are other references in that article that come up with somewhat more optimistic and somewhat less optimistic figures for the cost of wind energy. The BWEA study is actually right in the middle of the range - so it's probably the most reasonable guesstimate. Also, I doubt anyone believes that wind power is enough to meet US electricity production needs - not even close. We're going to need nuclear power and solar and some hydro (and yes, some coal and gas). We're also going to have to cut those demands back fairly sharply - because saving energy is much easier and cheaper than generating it sustainably. What I'm trying to point out here is that our OP's efforts to suggest an all-nuclear solution is not the best way to go. Besides that, having a diversity of methods gives us the most flexibility in the future - if we suddenly find some horrible and unforeseen problem with any one of the technologies, we can phase it out relatively quickly and do something different without having the entire country invested in one solution. SteveBaker (talk) 15:24, 3 March 2010 (UTC)

Methane from CO2 and H2?[edit]

Given, a priori, a limitless supply of cheap energy, is it possible to make methane from carbon dioxide and water, and then onto more complex hydrocarbons? Obviously this would be highly inefficient, but if workable, might be useful where a high energy/weight density power store is needed, such as aviation? CS Miller (talk) 19:21, 2 March 2010 (UTC)

It's certainly possible - but if we can get cars and trucks and trains and boats off of hydrocarbons, then we would be able to use biofuels like ethanol for aircraft. The point is not to get fixated on a single solution such as "produce 100% of mankinds energy needs from nuclear reactors" because doing that forces you into that kind of extreme inefficiencies. SteveBaker (talk) 20:09, 2 March 2010 (UTC)
But how in the world are you gonna "get cars and trucks and boats off of hydrocarbons" in the first place? Any ideas, Steve? 24.23.197.43 (talk) 05:02, 3 March 2010 (UTC)
Introduce a tax on carbon emissions that makes it cost effective to switch to electric or hydrogen cars and sit back and watch. Easy. (Technically easy, anyway. Politically it's a nightmare.) --Tango (talk) 05:50, 3 March 2010 (UTC)
I was asking specifically for technological ideas on how to do that, not the same ol' carbon-tax thing that would only reduce emissions by reducing economic activity. Specifically, I'd like to know how you plan to (1) improve the energy density and recharge rate of electric cars so it won't take all day to recharge their batteries, (2) address the serious safety hazards of hydrogen-powered cars, and (3) adapt either or both technologies to produce enough power for your typical eighteen-wheeler? I'm standing by for any ideas you might have. 24.23.197.43 (talk) 06:03, 3 March 2010 (UTC)
I plan to sit back and watch while businesses work out how to make profit. They are extremely good at that. The problems you mention are fairly simple engineering problems - throw enough money at them and a solution will turn up. I'm not remotely qualified to solve the problems myself, but I have great faith in the ability of the world's experts to do great stuff when given the necessary funding. --Tango (talk) 06:12, 3 March 2010 (UTC)
Are you saying that the hydrogen-safety issues and the battery charge limitations are "simple engineering problems"?! Obviously you had never worked with either of these things (and especially not hydrogen)! Anyone else have any ideas? 24.23.197.43 (talk) 06:42, 3 March 2010 (UTC)
The battery charge issue is trivial. Simply have a standard form factor and connector, and have a battery exchange system at the fuel station. Drop off the old one, put in a new one. That should take less than refueling takes now. You can also keep two at home, one for charging, one for using. Use a deposit system or something to handle battery ownership and possession. There is a company in Israel that is developing that system, but I forgot the name. --Stephan Schulz (talk) 13:55, 3 March 2010 (UTC)
It's not really that simple. A full set of batteries for (for example) a Prius costs several thousand dollars. They are a huge fraction of the cost of a car. So how many of these can a typical gas station afford to have "in stock"? 60? That's maybe $150,000...a big investment. Yet they might easily see 60 customers per hour (gas stations have maybe a dozen gas pumps - they see WAY more than 60 customers an hour). That means that they have to be able to recharge these things at a rate of one per minute - an hour to recharge a battery pack! That's not possible right now - so they'll need more like 600 battery packs in order to satisfy a 60 customers per hour rate - and now they have a 1.5 million dollar investment in batteries alone - that's not including the difficult robotic lifts that swap the batteries out and all of the charging stations. So now we have (probably) a multiple millions of dollars cost to opening a new battery-swap station. For those to be common enough for everyone to use, we need to have every gas station in the country spend several million dollars. There are close to 200,000 gas stations in the US alone - so if we're generous and put the cost at $2,000,000 to equip one with batteries, rechargers and battery-swapping robots - you're looking at 200 billion dollars of outlay. That's not outragous - but there is a chicken-and-egg problem. Until there are (let's say) 100 million cars out there that can use battery-swap technology - how is this $200 billion investment going to pay off? Nobody is going to buy a battery-swap car until there is enough infrastructure out there so that when they roll into a gas station with 10 miles worth of charge in their batteries they won't hear "Sorry - we just sold our last battery - it's going to be 5 hours until the next one is recharged!"
I think we really need a cultural change. We need to have people buy 100 mile range electric cars for daily driver usage (with charging sockets in company parking lots) - and be able (and willing) to rent long-range gasoline vehicles for road trips. It's not a terrible restriction - I'd go for it in a heartbeat because it makes sense. But for too many people, that's not an acceptable solution. SteveBaker (talk) 14:42, 3 March 2010 (UTC)
First, those are not technical problems, they are economic problems. Moreover, your calculation is off. Not everyone will have an electric car immediately, and not every gas station will have to provide a battery service immediately. If there is one per neighborhood that's enough - assume electricity is half the price of fuel per mile, people will gladly drive a bit further to the next station. I know some drive 20 km to fuel up for a few cents less per liter here in Germany. And those gas stations that offer the service will only need enough supply to deal with actual business (plus a few spares for reserve). Of your 60 cars/hour, in the beginning only one or two will be electric. As the business ramps up, the supply of batteries be ramped up. And, of course, if batteries are standardized and and used widely, their price will come down quite a bit. --Stephan Schulz (talk) 18:49, 3 March 2010 (UTC)
Thinking about this - what you'd really need is a system where the car is told "I plan to drive from here to there today" - the car then calls up gas stations along the route and books the batteries it's going to need to make the trip so you'll know they are going to be ready and charged at the gas station when you roll up there. With that degree of confidence about availability, the gas stations could plan ahead...maybe even move a bunch of pre-charged batteries in a truck from some central storage place to cover peak demands in unusual circumstances. If you changed your mind and take a different route - you'd have to be prepared for the car to tell you that you can't go that way because there aren't enough available batteries en-route to make it to your destination - maybe you'd even have to pay money to the gas stations whose batteries you'd reserved but didn't take. Combined with the ability to recharge at home and at work - this might produce a workable solution. But it would take some considerable consumer re-adjustment to make that work. SteveBaker (talk) 15:13, 3 March 2010 (UTC)
Another idea is to make the batteries smaller - say a Prius will normally get 3, a Lexus 5, and an E-Hummer 256. If a gas station runs low, they can ration batteries and, in the (hopefully rare) pinch situation, just provide enough to tide the driver over to the next station along his route. Or they can provide only partially charged cells (at a discount, of course), again to tide the driver over. Sure, it's an annoyance, but then so is gasoline, and fuel stations running out of gasoline is not unheard of even in the US. --Stephan Schulz (talk) 18:53, 3 March 2010 (UTC)
The thing about waiting for businesses to do this in order to make a profit is that their definition of "profit" is different from ours. If there is no cost whatever to dumping CO2 into the atmosphere (and there currently isn't) - then it is certainly vastly more profitable to burn coal and cause unending amounts of grief to future generations than it is to research cleaner technologies. If you want capitalism alone to cause free enterprise to want to do it - you have to adjust the rules such that producing CO2 comes up on the "costs" side of the balance sheet. If "producing a shit-load of CO2" is expensive then in order to make a profit, they'll have to clean up their act. The alternative is to write laws to simply make it illegal to produce more than some limit of CO2. I don't really care which we do - but the latter tends to upset the "free enterprise" thing.
In the automobile industry, (for example) we have the CAFE standards that do it the latter way - we require that the average fuel consumption of automobiles sold in the USA meet some specific goal. But we don't reduce that number fast enough - and we don't do similar things for things other than cars. One gasoline powered snow blower/leaf blower/chainsaw/lawn mower can produce truly insane amounts of pollution with (mostly) zero regulation. Big ships are often required to burn relatively clean kinds of oil when in US waters - but are allowed to switch to cheaper, exceedingly dirty stuff once they are out in international waters.
This kind of regulation is exceedingly patchy and because it's done with a complicated network of tiny rules and regulations, it's easily abused by lobby groups who can get a law changed for a single industry segment without causing national outrage. The good thing about "carbon taxation" is that it can apply uniformly across the whole of business with a uniform pricing scheme. No one industry would get their own laws - so the cost of CO2 emissions shows up on their balance sheet - and with luck, that will cause the profit mechanism to kick in and cause them to do research. It also has the nice property of creating the most incentive for the worst offenders. Coal power plants shouldn't be the cheapest form of energy - they should be by far the most expensive...a proper accounting for their real costs would make that clear and would result in more appropriate technologies becoming so blindingly obviously "profitable" that money would flock into building windmills or nuclear power plants or whatever it takes to solve this problem. SteveBaker (talk) 14:22, 3 March 2010 (UTC)
Agree absolutely. The best and simplest way to deal with the commons is to assess a fair price and set taxation so that that price will be internalized by businesses using the commons. Then let the market do its thing. To avoid disruption, taxes can be phased in in a predictable manner over 10 years or so. --Stephan Schulz (talk) 18:39, 3 March 2010 (UTC)

star composition[edit]

At the densities required to allow hydrogen to fuse into helium or any other element up to iron will the material with the higher atomic weight be the one to fuse,i.e. if the amount of carbon is the same, will carbon be the element to fuse if the amount of hydrogen is the same? 71.100.5.197 (talk) 14:00, 1 March 2010 (UTC)

If I understand your question correctly, some fusion reactions are more common on the aggregate than others. At different temperatures/densities, different reactions dominate. --Mr.98 (talk) 15:05, 1 March 2010 (UTC)
Does a star burn up all its hydrogen or does helium start fusing before all the hydrogen burns up. In other words what conditions cause helium or carbon to take over as the primary material of fusion? Is it the absence of less heavy elements or just that temperature and density favors one over another? In other words if you injected a star size amount of hydrogen into a helium burning star would it start burning hydrogen again or keep burning helium? 71.100.5.197 (talk) 17:17, 1 March 2010 (UTC)
It depends how much hydrogen you inject. The hydrogen doesn't run out entirely, it just gets too low to sustain sufficient fusion to stop the star collapsing under its own gravity. The star then starts to collapse until the heat and pressure is enough to fuse helium (it will still be fusing some of the left over hydrogen). If you injected a little more hydrogen it would just fuse that hydrogen while still fusing helium. If you injected a lot then it would fuse the hydrogen, generating lots of radiative pressure that causes the star to expand and cool, stopping the fusion of helium until the hydrogen runs out again and the star re-collapses. --Tango (talk) 17:50, 1 March 2010 (UTC)
It also depends on the star. The sun is fairly layered - it's slowly accumulating helium "ash" in its center. Eventually, the pressure will be high enough to start helium fusion. But some smaller stars (e.g. red dwarfs) are completely mixed by convection. They can keep fusing hydrogen much longer. --Stephan Schulz (talk) 22:08, 1 March 2010 (UTC)
The concept of a helium flash is also relevant. --Tango (talk) 01:30, 2 March 2010 (UTC)

Why not take from the sun?[edit]

Instead of expensive fusion initiation why not just go to the sun and scoop some already fusioning material and just keep it going with cheap gasses on Earth? 89.204.153.2 (talk) 14:49, 1 March 2010 (UTC)

First, getting to the sun at all is hard, because you need a very large delta-v. Second, the nuclear fusion in the sun takes place in the core, so it would be incredibly hard to create something that could survive the temperatures and pressures needed to reach the core, and get back out again. Third, the fusion reactions there are sustained by that pressure, which is a result of the gravity of the sun's enormous (compared to the earth) mass. If you remove the fusing material from that environment, the reaction will not be sustained. -- Coneslayer (talk) 14:53, 1 March 2010 (UTC)
I think "incredibly hard" is probably optimistic. I suspect there is no human-made object that could possibly make it to the core of the Sun and back in one piece. --Mr.98 (talk) 15:01, 1 March 2010 (UTC)
...and in any case we already have the technology to initiate a fusion reaction - that is relatively easy. What we lack is the technology to contain and control a fusion reaction without consuming more energy than it produces. Gandalf61 (talk) 15:04, 1 March 2010 (UTC)
what if we don't try to bring it back then but just park a power plant on the surface of the sun? Isn't cooling trivial when you had that much energy at your disposal? 89.204.153.101 (talk) 15:15, 1 March 2010 (UTC)
Good point, we could just have the power plant convert the energy into some form of radiation and 'beam' it back to the Earth. I think that the method has been tested before, it just might work! All we need is a power plant that can survive on the surface of the Sun. --144.191.148.3 (talk) 15:25, 1 March 2010 (UTC)
what if you use the energy right there? For example, A server farm doing massive massive number crunching a la NSA or complex rendering a la Pixar? Then would it make sense? 89.204.153.97 (talk) 15:45, 1 March 2010 (UTC)
It'll be tried soon and will succeed, but with unfavourable results. Bazza (talk) 15:55, 1 March 2010 (UTC)
The temperature on the surface of the Sun alone is some 5,778 K — nearly 10,000ºF. Even with a lot of energy I don't see that as being a "trivial" cooling problem, even you neglect the fact that the surface of the Sun is rather inhospitable for a number of other reasons. (And even more so, it's hard to imagine any on-the-sun/in-the-sun based situation that is going to be cheaper than a terrestrial option.) --98.217.71.237 (talk) 16:18, 1 March 2010 (UTC)
None of these answers makes any sense for me. You're talking about FREE energy, ALL around you. I just don't see why you can't use it to cool your power plant.  :( :( :( This thing doesn't make any sense to me. Let's get down to something more basic: how does a regrigerator work in space? Normally, a refrigerator uses energy to move heat from one place to another (same as an air conditioner). So, HOW does it do that on the surface of the sun? Thanks. 84.153.196.55 (talk) 16:29, 1 March 2010 (UTC)
So you want to use incredible heat to cool things down? Not so simple, methinks. LargeScaleForest (talk) 16:34, 1 March 2010 (UTC)
I for one hope no one has taken this thread seriously since about the second or third post... The first problem with gathering energy 'on the surface of the sun' is that all modern energy harnessing techniques aside from mechanical such as tidal energy, and photovoltaic with proton-electron conversion; require a *difference* in heat energy between one place and another in order to exploit for gainful purposes. The air inside of a combustion chamber vs. the outside air, for example. Since your whole power plant would quickly become the same temperature (unless you built it with a size proportional to the sun itself, say ten million miles across) and your ability to gather up energy would be rendered null. And, for what it's worth, refrigerators only work in space if you can count on infrared emission of the heat they relocate, since there is no air to blow across the condenser coil. --144.191.148.3 (talk) 16:48, 1 March 2010 (UTC)
That's exactly the problem. On a small scale, try using the heat of your oven to make ice cubes! We have a free fusion reactor provided for us just eight light-minutes away, so if we want an engineering challenge, why not just tap some of the energy as it arrives on earth (or we could tap the sunlight as it goes past the earth, but this would cost more, and would contribute to global warming.) Coincidentally, I've just been listening to Set the controls for the heart of the sun. Dbfirs 18:25, 1 March 2010 (UTC)
In order to use power to cool things - you have to take the heat out of the cool thing and somehow dispose of it - but the only way to do that is to funnel that heat to a radiator that is itself hotter than the surrounding environment. (Don't believe me? Check out how hot those coils at the back of your refrigerator get! They have to be hotter than the room the fridge is in.) So our solar refrigerator would need a radiator hotter than the sun itself. What could we possibly make that of? There are no materials known to man that wouldn't melt (or more likely boil) at those temperatures. SteveBaker (talk) 00:33, 2 March 2010 (UTC)
Certainly the idea of grabbing a bit of sun is both crazy-impossible - and completely unnecessary. As others have said - the problem isn't getting the fuel - and it isn't starting the reaction going. The problem is containing something that's as hot as the surface of the sun using 'normal' materials. There are no materials that we know of that can survive that much heat without melting. Hence we have to use the magnetic properties of the plasma and make massive magnetic fields to contain the stuff without it coming near the walls of the reactor. But those magnetic fields don't stay stable, the kink and bend and let the plasma loose. It's really tough - which is why we haven't solved it yet.
As for picking up energy at the sun and beaming it to earth - why bother? The sun is doing a great job of beaming energy at the earth without any help from us! The problem is collecting that energy when it gets here. There is plenty of sunlight lighting up boring bits of our planet that we could (in theory) gather up and use. But the cost of all of those solar panels is daunting - and all the time that there are cheaper alternatives, we're going to go on using them. The other problem with solar energy (that it shuts off at night) would apply to power collected near the sun and beamed here somehow. So there are no benefits to doing that...and the costs would be spectacular.
SteveBaker (talk) 00:28, 2 March 2010 (UTC)
Forgive my nitpicking, but the surface of the sun has no fusion and isn't nearly hot enough. Containing something at 6000 K is damn easy compared to the Tokamak operating temperature of 20-100 million K. Also, collecting energy near the sun and beaming it to Earth isn't entirely crazy. We get ~1370 W/m^2 at the top of the atmosphere, but if you place a satellite around the sun at say 5 solar radii, you could get 2.5 MW / m^2, so you'd only need 1/1000th the number of solar panels provided they could stand the heat. Put that energy into a collimated beam towards Earth, rather than letting it spread out in all directions, and there is a potential benefit, though in practice I can't imagine how you would build such a system without the sun pretty much instantly destroying it. Dragons flight (talk) 01:07, 2 March 2010 (UTC)
You also would need to be careful that the beam you would send from your theoretical power satellite goes exactly where you want it. Otherwise, we might see something like the superweapon in Golden Eye. Googlemeister (talk) 14:34, 2 March 2010 (UTC)


somebody above wrote "The problem is containing something that's as hot as the surface of the sun using 'normal' materials. There are no materials that we know of that can survive that much heat without melting. Hence we have to use the magnetic properties of the plasma and make massive magnetic fields to contain the stuff without it coming near the walls of the reactor. But those magnetic fields don't stay stable, the kink and bend and let the plasma loose." I understand why trying to contain the plasma magnetically is hard. Why don't we just use force fields then? A force field is, by definition, like a wall, but because it's not a normal material, it won't get hot. Why don't you just make a force field, and then a vacuum, like this:

crosssection:
[x|fusion|x]

wherein the fusion is the fusion reaction in progress, the | are the force field walls, and x is a vacuum? Then, you do not have to worry about direct energy transfer to your wall through convection. As for radiation, I actually don't know if heat radiates through a force field, I imagine it must as I have not heard of anyone saying that a force field is reflective of radiation. Is there any research being done along this avenue? 82.113.121.105 (talk) 00:44, 3 March 2010 (UTC)

And how in Heaven's name do you create a force field??? 24.23.197.43 (talk) 06:50, 3 March 2010 (UTC)
The short answer is "you don't" - but Force_field is worth a read. SteveBaker (talk) 13:43, 3 March 2010 (UTC)
sometimes science is able to predict the qualities of things that can't be produced yet. Insofar as that applies at all to force fields, does real science have anything to say about what thermal insulation and what thermal radiation properties it must have? 82.113.121.110 (talk) 14:55, 3 March 2010 (UTC)

Three (or more)-particle annihilation events[edit]

Is it possible for there to be a matter-antimatter annihilation event in which there are three (or more) particles involved. I surmised from a lecture today (possibly incorrectly) that there exist particles with charges of +- 2e, which made me wonder if you could collide two electrons and one anti-particle of charge 2e leading to mutual annihilation of all three and conversion of their rest-mass- and kinetic-energies into photons.

The question intrigued me becaus (again, if i recollect correctly) a classical triple collision is mathematically singular, that is, if three classical bodies were to collide at exactly the same time there is no way to determine the resulting trajectories.

Can anyone shed any light?

130.209.241.193 (talk) 16:31, 1 March 2010 (UTC)

No, that couldn't happen. A particle can only annihilate with its unique anti-particle. While charge does need to be conserved, it isn't the only conserved quantity. Things like lepton number would not be conserved in your example. (I don't think there are any elementary particles with charge +/- 2e, but something like a helium nucleus has charge +2e, or you may be thinking of an up quark with charge +2e/3.) --Tango (talk) 17:53, 1 March 2010 (UTC)
">2 particles" and "other than its own antiparticle" are separate issues. I don't know about the former, but for the latter, Zenone, Silvio Giovanni (1980), Antiproton Neutron Annihilation at Rest Into Kaon Antikaon-Pion Final States (Ph.D. thesis abstract), Syracuse University  is one of many such articles googling found me. DMacks (talk) 19:37, 1 March 2010 (UTC)
That sounds like an odd definition of "annihilation". If the final state includes fermions, it doesn't feel to me like the matter has been annihilated, just changed. --Tango (talk) 20:38, 1 March 2010 (UTC)
Yeah, this is beyond my field, I don't know how literal/technical the definition of "anhiliation" is in the field or anything about the (non)-presence of particles with mass in the products. DMacks (talk) 20:42, 1 March 2010 (UTC)
A Proton, an electron and a anti-neutron could have a triple anihilation into a neutrino plus photons. If fermions are not allowed in the final state than one of the three initial particles would have to be a boson. You could have for instance a neutron, a anti-proton and a W+ triple anihilate into photons.Dauto (talk) 01:28, 2 March 2010 (UTC)

Native American Height[edit]

My tribe is considered shorter than the average adult in the US (NW Canada). However I went to several pow wow's in the East Coast US and Eastern Canada and am still amazed how tall the native american people (men) were there. I'm talking over 6'3". Was what I saw unusual or is there an explanation for this? --Reticuli88 (talk) 16:41, 1 March 2010 (UTC)

Our human height has a link to details on the unusual height of Plain Indians [4] but not eastern ones. Rmhermen (talk) 20:25, 1 March 2010 (UTC)

Here are five possibilities: 1. The description of the tribe as short is old and obsolete because of improved health and nutrition. 2. The description of the tribe as short is old and obsolete because of continued intermarriage with people of European ancestry. 3. The description of the tribe as short was inaccurate even at the time. 4. Differential attendance at your gatherings-- tall people for some reason were more likely to be present. 5. Misperception: you noticed the tall people more, but they are atypical (or not tribe members) and the average is truly a bit short. Like any of these? By the way, the average adult male height in the US and Canada is close to 69.5 inches. alteripse (talk) 02:18, 2 March 2010 (UTC)

Re: The Seinfeld Junior Mints episode[edit]

What would be the likely effects (if any) of a Junior Mint getting left floating in between one's internal organs after an operation? Assume said mint is perfectly clean of any germs/bacteria.20.137.18.50 (talk) 17:46, 1 March 2010 (UTC)

Why would you assume that?? —Preceding unsigned comment added by 89.204.153.67 (talk) 19:00, 1 March 2010 (UTC)
To get past consequences I already know.20.137.18.50 (talk) 19:02, 1 March 2010 (UTC)
In that case, there would likely be a foreign body reaction within the connective tissue into which the mint settles. Macrophages would attack and fuse in an attempt to engulf it -- sort of like they did in Metchnikoff's seastar embryos. DRosenbach (Talk | Contribs) 20:04, 1 March 2010 (UTC)
Might it not dissolve before that could happen? It's a warm, wet environment - and those mints dissolve in your mouth in a short amount of time. Aside from the possibility of infection, I would kinda expect the sugars and starches to basically vanish. But if you just had an operation, surely the medical staff would be on the watch for possible infection and treat with antibiotics as soon as symptoms showed up. It's hard to be sure - but it seems possible that the answer might be "Not much". But it's tough to know for sure. SteveBaker (talk) 00:16, 2 March 2010 (UTC)
I stand corrected -- I did not know what a junior mint was, apparently. If you would drop some popcorn, let's say, what I said above would likely apply to that :) DRosenbach (Talk | Contribs) 00:39, 2 March 2010 (UTC)
But we have an entire article on the subject: Junior Mints - WHAAOE! - I'm horrified that you didn't know that! :-) SteveBaker (talk) 02:33, 2 March 2010 (UTC)

────────────────────────────────────────────────────────────────────────────────────────────────────the article on Infiltration (medical) may be of some assistance. I know when donating blood, occasionally the needle with slip out of the vein, and blood will pool under the skin. (At least, for me - even then, it's totally safe.) This causes an ugly bruise, but my understanding is that this infiltration of blood is slowly absorbed back into the body. It sounds reasonable that the same thing would happen to a Junior Mint. (disclaimer:not a doctor} -Avicennasis @ 19:37, 3 March 2010 (UTC)

Citric acid[edit]

is it true that Citric acid is converted by the body into baking soda? —Preceding unsigned comment added by 67.246.254.35 (talk) 18:30, 1 March 2010 (UTC)

No. Citric acid is primarily relevant to the citric acid cycle, which has nothing to do with baking soda. Note also that citric acid and baking soda react energetically; an attempt to transmute one into the other would just cause a reaction into their byproducts. — Lomn 19:42, 1 March 2010 (UTC)
I'm wondering - did you confuse bicarbonate with baking soda? The acidosis article says that decreased bicarbonate production can lead to acidosis - it's used to balance the pH of the body. I won't pretend to understand it - I just found this by wiki-surfing. Vimescarrot (talk) 21:31, 1 March 2010 (UTC)

why is it okay for people with acidosis to have fresh lemons then? —Preceding unsigned comment added by 67.246.254.35 (talk) 21:19, 1 March 2010 (UTC)

Does anyone have a pointer to a scientific (i.e., not food quackery or Edgar Cayce hooey) discussion of the alleged alkalizing effect of lemons? --jpgordon::==( o ) 15:14, 2 March 2010 (UTC)
The low pH lemon is broken down in the stomach so it has no direct contact with the blood, so it wouldn't affect anyone with acidosis. In any case, if it magically did, the blood is buffered and can withstand pretty significant changes in pH. Regards, --—Cyclonenim | Chat  17:22, 2 March 2010 (UTC)

Semantic web[edit]

What, if anything, does the term "semantic web" even mean? —Preceding unsigned comment added by 89.204.153.98 (talk) 18:46, 1 March 2010 (UTC)

It's an idea that the meaning of the contents of a web page can be encoded in a way that specially written, hypothetical computer software is supposed to be able to understand. See the Semantic Web article, or wait for SteveBaker's long post which is sure to come below. Comet Tuttle (talk) 19:09, 1 March 2010 (UTC)
Jeez - talk about being taken for granted!
I happen to be a fan of this idea. Web pages are written for humans to read. That's OK as far as it goes - but it makes it exceedingly difficult for computers to understand them. The idea of the semantic web is to encode the information in a web page into a rigid, logic-based language that states things unambiguously for the sake of computers. (I rather like Cyc - but there are many others). If computers could read that data, they could fairly easily turn it into English for us (perhaps not very beautiful English...but definitely understandable). If we had that then search engines could be instructed to produce the exact right results - and it would be easily possible to have your computer read all of the pages that were found and return a summary of all of that information for you. The idea that any computer could surf the web and look for answers would enable all sorts of possibilities that would seem a lot like Artificial Intelligence. SteveBaker (talk) 00:11, 2 March 2010 (UTC)
On the other hand if we had real AI none of that would be necessary or desirable. Dauto (talk) 03:48, 2 March 2010 (UTC)
That's true - but we're really no closer to getting true AI than we were when research on this was started in the late 1960's. Besides, giving an AI system a huge stock of "common knowledge" is an important part of getting it to work - a very intelligent computer that didn't know that water is wet or any of a gazillion other common knowledge kinds of thing would appear very stupid to us. You can argue that an intelligent being could deduce this from reading the Wikipedia article on Water - but the act of reading really requires that a large pile of common sense be already in place. But no matter what, AI is hard - and writing software that traverses a semantic web is easy. SteveBaker (talk) 20:04, 2 March 2010 (UTC)
The first impression I got of the semantic web idea is that it's a system where humans work twice as hard in order to take a small burden off machines. That's not how we usually do things, we usually have the opposite aim. Perhaps it's good for some parts of the web, though. I guess it would be useful for sites which already tag things in ways which could be standardized. Seems less useful for, say, a personal homepage: oh joy, extra coding. 81.131.42.83 (talk) 11:10, 2 March 2010 (UTC)
What????? Humans put in immense effort to make the damned machines bend to their will. Ask any programmer. Comet Tuttle (talk) 17:33, 3 March 2010 (UTC)
The problem is that computers really can't do this for themselves...but if we do it for them, we'll get back many times more than we put in. (Or so the theory says!) SteveBaker (talk) 20:04, 2 March 2010 (UTC)
It's not really as dumb as all that. The idea is to save the data you already have so that the computer doesn't have to try to infer it later (which computers are too dumb to do (computer scientists, actually)).
Here's a simple example that affected me recently: I enjoy the local college radio station and sometimes in my car I would like to know what song is playing. I wanted to write a little app for my Google phone that would go out to the station's website, grab their playlist, and display it on my phone. Now whoever wrote the program that generates their playlist could easily have given it semantic qualities like this:
<span class="song_name">Small Change</span> by <span class="artist_name">Tom Waits</span>
They already had the name of the song and singer right there, but instead chose to do something very unsemantic like this:
<b>Small Change</b> by <i>Tom Waits</i>
So now instead of just looking for things tagged with "song_name", my program has to go through the page and look for "the first bold characters in each row of the third table but skip the first row". When they change the visual formatting of their playlist page in any way it is likely to break my program. It's stupid, and making the page more semantic would not have caused them any effort at all. Obviously the "semantic web" where everything is tagged is another step, but just making things a little smarter isn't hard. --Sean 20:48, 2 March 2010 (UTC)
Yes, because the inventors of HTML turned their back on one of the fundamental ideas of SGML that they based it on, and conflated the structural and presentation properties in a single system. --ColinFine (talk) 21:37, 2 March 2010 (UTC)
The Semantic Web idea envisions a Paradigm shift in how we humans get access via our machines to data sources on the web. It does not presume to create data of itself nor to indulge in spontaneous creative art. When the uncontained enthusiasm for the idea blows over, as it must, the view of a sceptic is that this immutable mantra shall prevail and that we can't expect more than this amount of advance towards Utopia. A sceptic can be wrong too. Cuddlyable3 (talk) 22:42, 2 March 2010 (UTC)
For the record, I wasn't taking SteveBaker for granted; I was forecasting a force of nature that was as inevitable as the Sun rising tomorrow. Oh, maybe that was taking it for granted. Comet Tuttle (talk) 01:11, 4 March 2010 (UTC)

LCD Clocks and Plasma Balls[edit]

About a decade ago I used to own a plasma ball. I had it next to my bed next to an old fashioned LCD alarm clock. One of the black and grey displays. When I turned on the plasma ball the LCD alarm clock would go wild. Segments of the figures would flash on and off in a seemingly random fashion. I assume it was due to some kind of electromagnetic interference. I was wondering what exactly. What happens in the plasma ball, and what process in the LCD alarm clock does it disturb, and why? •• Fly by Night (talk) 20:55, 1 March 2010 (UTC)

There are some really high voltages and high frequencies present in those balls (35 kHz, 2–5 kV) - and the arcing inside is producing frequencies that are all over the dial. It doesn't surprise me that it would upset your clock. Two things might help - one is obvious - which is to move the clock as far away as possible from the ball - whatever electromagnetic junk the ball puts out will decrease as the square of the distance - so twice as far away means a quarter the amount of interference. If they are an inch apart now then putting them a foot apart reduces the noise by a factor of 144:1. Secondly, it's possible that the interference is travelling through the wall socket from one to the other. If you could plug one of them into a different outlet, then that might fix the problem.
The reason for the problem in this case is almost certainly that your alarm clock also has a radio in it - that means it has an antenna that's tuned to pick up radio frequencies. Once those signals get inside the box, they can cause 'crosstalk' in nearby wires. Those random spikes can look like digital data to a computer or other digital electronics could certainly crash the little computer inside by messing up the instructions it reads out of it's memory. But there are any number of other detailed mechanisms that could cause this kind of thing and it's really impossible to figure it out.
SteveBaker (talk) 00:03, 2 March 2010 (UTC)
It was a battery operated alarm clock, and it didn't have a radio. It was a little one that just beeped when it was time to get up. The globe's electromagnetic field was getting inside the LCD and causing segments to misfire. I guess that the segments of the figures are activated by an electrical current. So somehow the electromagnetic field was turning into electricity inside the LCD and making it misfire. •• Fly by Night (talk) 12:54, 2 March 2010 (UTC)
Yes, the segments are controlled by voltage (rather than by current), and the circuit is matrixed, so you will get apparently random effects from varying electromagnetically induced low voltages on just a few elements of the matrix. It would be interesting to see whether you could reproduce the effect with static electricity - amber (or just a plastic comb) rubbed on dry wool. Dbfirs 19:12, 2 March 2010 (UTC)
As SteveBaker said, plasma balls generate high voltage, low current fields. This extends into any nearby wiring. LCD devices (especially 7-segment displays), use high voltages (around 100V AC, IIRC) at low currents to affect the twist of the crystals in the display. The plasma ball might have been inducing a high enough voltage in the display to cause it to twist. CS Miller (talk) 19:33, 2 March 2010 (UTC)

Line between species[edit]

How hard set are the lines between species? I imagine at some point maybe 1 out of 10 matings between the 2 branching "species" would produce fertile offspring and then 1 out of 100 and so on. But is there really a hard limit? So for example if a woman and a horse (gross I know but I'm not sure how else to phrase this)...is there zero possibility of producing offspring (let alone fertile) or is it more like a 1 in 10,000 chance? TheFutureAwaits (talk) 21:09, 1 March 2010 (UTC)

It is very poorly defined. The existence of ring species really complicates matters. The fact that there are even interfamilial hybrids shows that our taxonomic system doesn't really work. It's a decent approximation for most purposes, though. --Tango (talk) 21:18, 1 March 2010 (UTC)
A human and a horse, zero probability -- the genomes are way too different. A human and a chimpanzee might be possible, just as it is possible for a horse and a donkey to produce offspring, although not fertile. Looie496 (talk) 21:35, 1 March 2010 (UTC)
You are not going to get cross-breeding between different species that are radically genetically different. Horses and humans belong to entirely different orders—they have little in common other than the fact that they are mammals. Even amongst animals much more closely related to humans (e.g. orangutans, gorillas, chimps), the possibility of hybridization is thought to be basically nonexistent. For some long-standing speculation on chimp-human hybrids, see humanzee.
All of this is a little tangential to asking about the species concept. The species concept is necessarily fuzzy and not set in stone. But that fact does not mean that the genomes of radically diverged lineage are compatible. --Mr.98 (talk) 22:30, 1 March 2010 (UTC)
Wikipedia has articles on Liger and Tiglon that both have parents of the same genus but different species. Cuddlyable3 (talk) 19:50, 2 March 2010 (UTC)
There are lots of examples of hybrids of different species in the same genus. It is those in different genera that are particularly weird. It shows our definitions of genera are very arbitrary and don't mean the same thing in different parts of the animal kingdom. --Tango (talk) 20:14, 2 March 2010 (UTC)
Why do we restrict ourselves to the animal kingdom? Hybrids are frequently observed in the plant kingdom. --Kvasir (talk) 23:56, 3 March 2010 (UTC)

water[edit]

which way does water polarize the e-field of light, paralell or perpendicular to the plane of the surface? —Preceding unsigned comment added by 129.67.118.36 (talk) 21:16, 1 March 2010 (UTC)

Parallel. See Brewster's angle, although you may need to read it several times to decide which particular "planes" and "normals" the article is discussing. :) The diagram is reasonably clear, though. Tevildo (talk) 22:03, 1 March 2010 (UTC)

blatter infections and pregnancy[edit]

would blatter infections cause miscarriages in women by chance? ive been wondering bout that for some time... —Preceding unsigned comment added by Jwking (talkcontribs) 21:53, 1 March 2010 (UTC)

Do you mean "bladder"? As in a urinary tract infection? I think any sufficiently serious illness in the mother can cause a miscarriage (basically, her body decides it needs to worry about itself rather than a baby) and UTIs can get very serious, so I'd say "yes". --Tango (talk) 22:15, 1 March 2010 (UTC)
Yes yes yes. Bladder infections in pregnancy are serious and require immediate medical attention because left untreated they can result in premature delivery of your baby or miscarriage. If this applies to you, seek medical advice. Regards, --—Cyclonenim | Chat  17:25, 2 March 2010 (UTC)

Colder after chewing gum[edit]

Why is it whenever a person is chewing gum, mint flavored, then drinks a cold drink or cold water, is the cold sensation in your mouth so extreme? Sometimes you get an instant brain freeze effect. Can anyone shed some scientific light on this? —Preceding unsigned comment added by Zerojjc (talkcontribs) 21:57, 1 March 2010 (UTC)

See Menthol#Biological properties. --Tango (talk) 22:07, 1 March 2010 (UTC)
For the same reason why hot peppers taste hot, menthol tastes cold. They react with the same receptors, respectively. DRosenbach (Talk | Contribs) 00:41, 2 March 2010 (UTC)
And if one eats menthol with peppes it will feel both hot and cold at the same time!! Dauto (talk) 03:17, 2 March 2010 (UTC)

Malitol[edit]

What is Maltitol's history? Is it naturally occurring, like sorbitol?174.3.99.176 (talk) 22:15, 1 March 2010 (UTC)

Reading the first few lines of the article told me that it comes from starch. Beach drifter (talk) 22:17, 1 March 2010 (UTC)
Sorbitol certainly isn't "naturally occurring" - our article says: "It is obtained by reduction of glucose changing the aldehyde group to an additional hydroxyl group." SteveBaker (talk) 23:36, 1 March 2010 (UTC)
To be picky, that doesn't say that sorbitol is not naturally occurring, only that it is produced synthetically as well (or, could be, exclusively, but it doesn't say that). --Trovatore (talk) 23:43, 1 March 2010 (UTC)

Exorcists after "the Exorcist"[edit]

It seems to me that there is a regurgitation of exorcism in the Cristianity; particularly, in the Catholic Church. I had a glance to some film reports of exorcisms on youtube, both home-made and from TV programs, and I've got the impression that today's exorcism rite owe a lot to the movie the Exorcist. It seems to me that today priests and possessed people tend to behave and speak like the characters of the movie (as far as they can, of course). Is there an evidence of the influence of the movie on the behaviour of these people? --pma 22:28, 1 March 2010 (UTC)

It may be the other way around. I have heard it said that The Exorcist was a very accurate depiction of how exorcisms are handled. I couldn't find any reference to that in the article on the film, though. --Trovatore (talk) 01:49, 2 March 2010 (UTC)
Wikipedia has an article on Exorcism. The movie The Exorcist was the 2nd most popular film in 1974, has been the source of some urban legends, see the linked article that significantly notes that its critical reception has grown over the years. That is evidence of its increasing influence. The Catholic Church does not endorse its representation of exorcism any more than it endorses the conclusions of a more recent movie The Da Vinci Code. Cuddlyable3 (talk) 19:43, 2 March 2010 (UTC)
Thank you both for your answers. Well, it seems that the Church attitude towards The Exorcist is quite another story from The Da Vinci Code, whose content is evidently heretical. I see now we have an article on Gabriele Amorth, which is a kind of president of the official association of exorcists of the Catholic Church; it reports he appreciated the movie as accurate, although a bit exagerated (I'm glad to know it is, of course), but substantially confirming what Trovatore sais. But also, this suggests that there could be a feedback: that is, that the movie then influenced the scenography of the rite and increased its popularity. After all, if something inside you tells you that you should feel possessed (a mental disorder, a big social embarass, or the diable himself, or whatever) you may feel encouraged to let yourself go, if you have already learnt how to behave properly. --pma 23:07, 2 March 2010 (UTC)

TV color[edit]

In the USA colors seem to be a combination of red, blue and green at varying intensities to derive the combined color. Are there other countries that use a different scheme that if recorded and played back on TV's in the USA will show a blue exchanged with red? 71.100.5.197 (talk) 22:29, 1 March 2010 (UTC)

(Removed long discussion about the OP's questioning habits to the discussion page). SteveBaker (talk) 12:52, 2 March 2010 (UTC)
Well, no, not exactly. NTSC (what the USA uses for TV) does do color a bit differently than, say, PAL, does, and sometimes you do need to fiddle with the tint on NTSC. One presumes that playing a PAL on an NTSC or vice-versa could result in some color shift. But it should not result in colors simply exchanging, I don't thnk. --Mr.98 (talk) 22:33, 1 March 2010 (UTC)
All TV's, computer monitors, and color displays of all kinds use Red, Green and Blue. The main reason is that this is how our eyes perceive color - we have 'sensors' in our eyes that only pick up those three colors. Hence, this is the smallest number of colors (and the exact perfect ones) to trick us into thinking that we're seeing all colors possible. However, there are other animals (such as the humble goldfish) that can see in more than three colors. This would presumably mean that a goldfish would think that watching color TV would be somewhat like watching just a red/green display would be for us. Other animals (such as bees) see in parts of the spectrum where we can't see at all. Bees do a good job of seeing in the ultra-violet waveband. There are actually a very few humans who are tetrachromats who see in four colors. One of them who has been studied by scientists is an elderly lady in the UK - and she has reported that she finds color TV pictures somewhat lacking in full color...which is what we'd expect.
The reason there is a need to 'fiddle' with the tint on NTSC TV's is that NTSC misses a rather clever trick that PAL TV's use to keep the color looking good. With NTSC, the color is decoded and displayed very directly - but if the decoding circuit gets a bit out of sync, it has to be manually adjusted to get the color right again. PAL rather cleverly encodes the colors with the opposite signal on alternate lines of the image (PAL stands for "Phase Alternate Line encoding" - or something like that). That means that if one line of the image 'drifts' (say) towards green then the alternate lines either side of it must drift away from green by the exact same amount. Because our eyes don't perceive color at high detail, this 'alternation' blurs together to produce the exact right color in our brains - provided it hasn't drifted too far from the right values. That's pretty clever - and it's why a lot of Brit's call NTSC "Never Twice Same Color".
SteveBaker (talk) 23:49, 1 March 2010 (UTC)
Thanks for that explanation for the difference in NTSC and PAL. However, the problem I have encountered is a converter from VGA that switches red and blue regardless of setting to NTSC or PAL for output to a standard NTSC TV and to a S-Video/RCA composite input video card on a personal computer. The seller says it converts fine on his TV but for sure it does not convert fine on the buyers TV. What could be the explanation other than defective converter? 71.100.5.197 (talk) 00:00, 2 March 2010 (UTC)
What are you using when you connect to the TV? Also when you are testing with the video in card, When you say s-video/composite, do you mean you've tried to connect both S-video and composite? Are there any controls other then switching output from NTSC & PAL? Nil Einne (talk) 00:17, 2 March 2010 (UTC)
The converter has 2 binary switches, a VGA input/output/bypass connector, and S-Video output connector and an RCA output connector. With both switches set to off you are supposed to get PAL-B/B/G/H/I. With switch #1 on and switch #2 off you are suppose to get NTSC and with switch #2 on (regardless of switch #1 setting) you are suppose to get RGB out. I assume this applies equally to both the S-Video and the RCA output connectors. Regardless of connector setup to TV or to S-Video or to RCA on computer input card testing each unit and each possible configuration and connection in turn you still get blue and red colors reversed. 71.100.5.197 (talk) 00:46, 2 March 2010 (UTC)
I assume from this that the connections (wiring) are intact but that the switches might be inoperative. In any case my conclusion is that the unit(s) are defective. 71.100.5.197 (talk) 01:48, 2 March 2010 (UTC)
Do you have anything to try the RGB with? Also if there are multiple VGA connectors, have you tried plugging it in to one of the other ones in case you have the wrong connector? And the final obvious thought, have you tried fooling around with switch 2 and in particular, using it on the other setting in case you mixed it up? Nil Einne (talk) 02:18, 2 March 2010 (UTC)
RGB monitors such as the Amigo are hard to find now-a-days. I do have an Atari monitor but it would take some sync circuit interfacing to tap its RGB lines. Actually RGB is a technology that would have to use the S-Video output connector since it has horizontal and vertical sync lines in addition to the RGB analog lines. The original Radio Shack Color Computer may have used an RGB monitor but the RS Color Computer II I still have has only an RCA composite output connector for use with an antenna box to hook its up to the VHF or UHF TV antenna connector for use with channel 3 or 4. This box is what I'm now using to go from the RCA connector output to the TV. The connection to the computer RCA input connector, however, does not require this antenna box.Regardless of switch settings of which there are only three the red and blue revered color does not change. 71.100.5.197 (talk) 03:27, 2 March 2010 (UTC)
Do you actually know what sort of RGB connection the device outputs? Are you sure it isn't RGsB? Incidentally I believe projectors often use RGBHV. Also are you saying that whatever of the 4 possible settings (switch 1 on and off, switch 2 on and off) you set it, the output works but red and blue is reverse? Below however you appear to say it doesn't work however when set to NTSC and connected to a computer Nil Einne (talk) 03:56, 2 March 2010 (UTC)
The human eye is sensitive to all wavelengths from red through violet, not just to three specific wavelengths. Because there are three cone types, three primaries suffice to reproduce any hue. Many sets of three primaries will work. The choice of primaries is driven by practical considerations like the availability of cheap phosphors/filters/LEDs and compatibility with established standards based on certain primaries. There are (or at least were) some displays that used red-green-violet, orange-green-violet, and the like, and there's a lot of variation in the "red", "green" and "blue" used in RGB displays.
The NTSC signal uses a color space called YIQ. Y (brightness) is encoded independently, while I and Q (color) are encoded together as a signal whose phase is the hue (angle in the I-Q plane) and whose amplitude is the saturation (distance from the origin). The famous tint problem comes from this signal being out of phase. It's the TV's job to convert this into phosphor intensities, and in principle the TV can use whatever phosphors it likes as long as it does the conversion correctly. Though I guess that none of this ends up being relevant to the OP's question. -- BenRG (talk) 02:22, 2 March 2010 (UTC)
Its probably relevant in that the NTSC setting does not work either regardless of connection or switch setting at least with the converter unit whereas it works fine with all other devices I have connected to the computer that use NTSC correctly. 71.100.5.197 (talk) 03:33, 2 March 2010 (UTC)
So wait, if I understand you correctly, when you turn it to NTSC it doesn't work with your computer at all? Does it work with your TV? When you turn it to PAL it works? Does your computer identify the device as PAL? Nil Einne (talk) 03:56, 2 March 2010 (UTC)
On any setting the picture is still displayed but the red and blue colors are reversed. On the computer I adjusted the resolution from lowest and highest the video card and monitor would support. My question above was to determine if the converter might require a codec that switched blue and red color back to normal or if there was some other difference in signal say like what might be used in Russia which was incompatible with Standard US TV. Now I just think the converter is defective. 71.100.5.197 (talk) 04:50, 2 March 2010 (UTC)
If the switches don't do anything, then yes, it sounds rather dubious. I still don't understand what you mean by 'NTSC setting does not work either regardless of connection or switch setting at least with the converter unit whereas it works fine with all other devices I have connected to the computer that use NTSC correctly' since the switches don't do anything. In any case, it doesn't matter now I guess given your upcoming major life change. Do remember to disclose that this device is probably defective when you sell it, as you've said it's the moral thing to do. Nil Einne (talk) 10:11, 2 March 2010 (UTC)
I remember now DECO isn't it? Anyway I thought we were friends there for the longest time and now I realize it was you who went through some kind of life change... Anyway... to clarify. No matter whether the switches are set to produce NTSC, RGB or PAL the blue and red colors are reversed. i.e., the sky is red instead of blue. The sunset is blue instead of red. A field with a morning haze of light blue is a morning field of light red. Got it? Anyway... it also does not matter what resolution the computer viewing monitor is set to or which TV set is used so the only explanation I can come up with is that the device is defective accidentally such as the switches not working or temporarily defective by intent on the part of the seller to allow the seller to engage in the Defective Item Return Scam. I can't sell the device because I have already returned it to the seller who declared that it was not defective but working and together with the excess postage fee he did not refund and the 15% restocking fee he not only got a "working" item back to sell once again but a 30% profit. 71.100.5.197 (talk) 20:49, 2 March 2010 (UTC)
For clarification, as I said in my earlier response I've never gone by the name DECO, or any other name. Maybe you're confusing me with User:Jiuguang Wang, User:Dcoetzee (who remains an active wikipedian) or someone else you've had a run in with one of you numerous previous accounts. Anyway back to the original question, if the switches didn't do anything at all even change the output to PAL instead of NTSC as they are supposed to, this is something I would have emphasises to the sellet and it's clearly a flaw whatever they use in Russia, but I guess that's too late now. And you still haven't explained what 'NTSC setting does not work either regardless of connection or switch setting at least with the converter unit whereas it works fine with all other devices I have connected to the computer that use NTSC correctly' means since according to you now the switches don't do anything so there's no such thing as a NTSC setting but only one setting (since the buttons don't do anything) so the device either works all the time when outputting to a device like a computer with video in, or never works at all. And it's not clear to me from your responses whether the device is really outputting NTSC. It may be that the device is permanently on the RGB setting and however the device works when it does that, it reverses the colour when outputting to composite and s-video on that setting. Either way as I've already said, if the switches aren't working at all, that would be a clear cut sign the device is broken, and compatibility issues aren't relevant. Nil Einne (talk) 08:54, 3 March 2010 (UTC)