Wikipedia:Reference desk/Archives/Science/2014 July 25

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July 25

Anti Armor Weapons

I read in a forum that Kornet uses a low energy laser beam to guide the missile so that it cannot be discovered , my fist question is : does the TOW 2 have the same ability to be undiscovered ? My next question : are there any other methods to guide missiles - within SACLOS systems not fire and forget systems - which is resistant to jamming and detection ? 92.253.61.250 (talk) 08:11, 25 July 2014 (UTC)

See BGM-71 TOW for our article on the missile. According to the article, the wireless version of the TOW-2B employs a "stealth one way radio link", but no details are given and the statement isn't cited. The standard version uses a wire link for guidance, so there's no radiation to indicate the missile's presence - I'm not sure if that makes it "undiscoverable". Tevildo (talk) 09:03, 25 July 2014 (UTC)

Ask yourself this: Is a Sidewinder missile undiscoverable just because it uses passive infrared guidance? And this will answer your question whether any missile can ever be truly "undiscoverable". 24.5.122.13 (talk) 10:07, 25 July 2014 (UTC)

Hardening against coronal mass ejections?

I just read a story saying that a 2012 coronal mass ejection could have put Earth "back to the stone age" if it had hit us. Which makes me wonder: what would people need to do to prepare against them?

To start with, where would they do their damage? (This would be good to add to the article also) I had a clearly ludicrous notion of wrapping computers and power cords in tinfoil, but from very not-Wikipedia-grade sources it appears that the damage is mostly to big features, long transmission lines.

• Is this true?
• Would Germany, with its advanced state of conversion to solar power that I assume is more decentralized, be spared from the event to the degree they have done so?
• Would underground power lines be unaffected?
• Which power generation facilities would be affected?

Last but not least, since we've now seen an event like this, can we begin to estimate how long it is until we are hit by this? Wnt (talk) 12:51, 25 July 2014 (UTC)

It is true that we use computer-controlled machines to build machines to build our technology, so that if all surface computers were to be destroyed we would be in trouble. However, there should be computers in Cheyenne Mountain nuclear bunker, and its Russian/Chinese equivalents that will survive. There will be details of how to (re)build our technology stored on surface CD/DVDs that will survive, and on tape/hard drive deep in old salt-mines as long-term backups (Iron Mountain etc use old mines if available). The question is, can our just-on-time supply network provide sufficient food etc for us to survive the few years before we can rebuild everything? CS Miller (talk) 13:28, 25 July 2014 (UTC)

Our Electromagnetic pulse article should cover much of this. StuRat (talk) 14:08, 25 July 2014 (UTC)

Another one just missed us, according to this Guardian report ---- CS Miller (talk) 14:50, 25 July 2014 (UTC)

Don't see any mention of another one. Far as I can tell, the report just refers to the same 2012 event Wnt refers to (along with one in 1859 that we have an article on Solar storm of 1859). The report itself is from the past few days, as I'm sure is Wnt's report, that's just because NASA just put out the PR about it [1] and everyone is reporting it now. Nil Einne (talk) 15:48, 25 July 2014 (UTC)

BTW, the NASA PR has useful information. In particular it mentions a NSF study. Some quick searching ('National Academy of Sciences solar storm') finds [2] which is probably referring to the same study and gives a title which suggests it's [3] or NSF workshop report (working without registration copy).

The other papers referred to are [4] (wrong date but all the other details seem right so I guess NASA or someone who gave them the date screwed up) and [5] + [6] (found with a search for 'Nature Communications Janet G. Luhmann'). However as the first is about estimating the probability of such events and the second two are about an analysis of the 2012 eruptive event, it looks like they only briefly mention or don't mention at all the possible effects.

Also this is the related PR about the 2014 study [7] and has some cost and recovery estimates. Of course as a press release not a great source (amongst other things, very few details) but it does mention a study in the previous year (i.e. 2013). The NSF workshop report is from 2008 or so unless they do go their dates mixed up it's probably not what they're referring to. But again a quick search for '2013 solar storm 2.6 trillion' finds [8] which mentions a $2.6 trillion Lloyd's estimate from 2013 so the details match up with the Berkeley PR. The same search (or I guess the details from Telegraph) finds the report Lloyds report. They don't actually talk about the figure much, more about other stuff.

Oh and due to misremembering what the Berkeley PR said, I also looked for '2011 solar storm recovery' which found [9] which mentions and links to an OECD report OECD report.

I didn't look at these that well but the 3 reports, particularly the NSF and OECD ones look like they provide a resonable amount of information on what could happen. I think all 3 agree the effect could be fairly disastrous. I doubt any of them say anything about "back to the stone age". It doesn't look like that's even in the NASA PR. I'm not sure who came up with it, but I suspect it may have been a journalist somewhere. I did find one newspaper quoting a researcher but the full quote is "back to the stone age for days" [10] (however it looks to me like this only came after every paper and their dog were already talking about "back to the stone age").

Nil Einne (talk) 16:59, 25 July 2014 (UTC)

Note that the damage is not done directly by geomagnetically induced currents, these are too weak to cause damage. The problem really is that power transmission through the generators of a powerplant has to be extremely efficient. A 1 GW powerplant with 10 generators will be transporting a power of 100 MW through the generators, so 99% efficiency won't be good enough as that would mean that each transformer would be dissipating 1 MW of heat. This would cause the tranformer to explode. So, the transformers used in powerplants are extremely efficient and that comes with a big price tag. Power companies are not going to keep spare transformer on standby, they are just too expensive.

Then the effect of a geomagnetically induced current is to cause the core of transformers to get magnetized which will make the power transmission slightly less efficient. But that is then enough to cause the transformer to explode. What happens is that beyond a small threshold, a slightly less efficient transformer will lead to more heat to be dissipated and thus a higher temperature. But at that higher temperature the power transmission becomes even less efficient, causing even more heat to build up, eventually the whole thing explodes. If this happens to many powerplants, then you'll have problems operating the factories that are needed to make new transformers.

The best defense is to cut the power when a solar storm is predicted to hit Earth. Count Iblis (talk) 01:26, 27 July 2014 (UTC)

An electromagnetic potential of Brownian motion

Did a Brownian motion always had been an electromagnetic potential? Why the Wikipedia don’t include that?--Alex Sazonov (talk) 13:54, 25 July 2014 (UTC)

What the devil does Brownian motion have to do with electromagnetism??? 24.5.122.13 (talk) 17:14, 25 July 2014 (UTC)

I _think_ Johnson noise is what the OP's getting at. Tevildo (talk) 17:29, 25 July 2014 (UTC)

If been seek a Brownian motion as movements of electromagnetic charges, we been seek that Brownian motion always had a electromagnetic potential. But I have asked a question about a make been resonances by Brownian motion in which an electromagnetic charges lost’s or had their mass. Why's the Wikipedia don’ting include that?--Alex Sazonov (talk) 18:51, 25 July 2014 (UTC)

Which why losted mass of electromagnetic charges in Brownian motion up to had mass a twice?--Alex Sazonov (talk) 19:50, 25 July 2014 (UTC)

Don’tly been mind if a Brownian motion is been a low point of the theory of relativity?--Alex Sazonov (talk) 07:12, 26 July 2014 (UTC)

As all been know, in a Brownian motion an electromagnetic charges always been change to divide their volts by themselves.--Alex Sazonov (talk) 18:22, 26 July 2014 (UTC)

Hmmmm, part (c) of the illustration for Johnson noise has me wondering: can you use this noise to transfer heat energy? I understand of course that the noise source in a loop with a resistor is not really going to produce perpetual motion; but it seems like the resistor ought to heat, so the noise source ought to cool ... shouldn't it? Right now our article on solid state refrigeration is synonymous with the Peltier effect or other thermoelectric materials, but could you somehow make a system like this very noisy electrically, and find a way to apply power so as to somehow transmit a meaningful amount of energy this way? Wnt (talk) 19:28, 26 July 2014 (UTC)

Wnt, I been speak about a nuclear electromagnetic resonance, but you is been speaking about a electronical resonance which always been consists in an electronically transaction.--Alex Sazonov (talk) 20:08, 26 July 2014 (UTC)

Figure (c) is the Norton equivalent circuit for a noise source, not a practical circuit diagram. The ideal current source and the ideal resistor it depicts are both implemented by the real resistor in figure (a), not separate components. That being said, it would be possible to use the noise voltage produced by a resistor to power another circuit, but not to transfer a "meaningful" amount of energy, compared with simple thermal conduction between the two systems. If you wanted to transfer energy from a hot system to a cold system, where the only possible connection between them was electrical rather than mechanical, _and_, for some reason, you didn't want to use a thermopile or other device that uses the thermoelectric effect, it would work. But I can't see that ever being a practical requirement. Tevildo (talk) 19:58, 26 July 2014 (UTC)

I understand that Johnson noise is a really small amount generally, and hence the amount of heat moved would be infinitesimal... nonetheless, is there a law of physics that says it must be a small amount? Are we sure there's no way to make the circuit noisy enough that the electrical sort of "thermal conduction" might outstrip the ordinary sort, and begin to make inroads against the inefficiency of a standard thermopile? (Mostly these questions come from having no real appreciation for how the electrical noise decides on its amplitude - I keep thinking "what if we had a room temperature superconductor" and suchlike wishful thinking) Wnt (talk) 22:42, 26 July 2014 (UTC)

The (Johnson) noise power depends only on the temperature (and Boltzmann's constant), even if the resistance is zero, so that is a "law of physics" limit. The noise is due to Brownian motion of the charge carriers in the device, which will always exist for any conductor above absolute zero. There are other sources of electronic noise that might add some extra power, but Johnson noise will be the dominant component for a passive, non-semiconductor, device. The _efficiency_ of the transfer will be close to 100%, but the _rate_ of transfer will be very low - in a (fairly) realistic situation, where we have two insulated boxes, each with a resistor in them, with the resistors connected with ordinary wires, the major route for heat transfer will be the thermal conductivity of the wires, rather than the tiny noise power generated by the hot resistor. If we had wires with low electrical resistivity but high thermal resistivity, the noise power might become a significant component of the heat transfer. Tevildo (talk) 23:20, 26 July 2014 (UTC)

Not the answer I wanted to hear, but it does sound convincing. :( Wnt (talk) 00:13, 28 July 2014 (UTC)

If in nuclear physics a science quest about a safe’s energy always been decide, why in electronically physics this quest not been decide at now.--Alex Sazonov (talk) 20:27, 26 July 2014 (UTC)

The USSR almost had the thermo-resistors in which always been a low thermoresonance, but why the safe’s energy is not been powered in, I don’t know.--Alex Sazonov (talk) 10:13, 27 July 2014 (UTC)

Because thermo-resistors don't GENERATE energy -- they vary their electrical resistance with temperature, so they actually DISSIPATE electrical energy under ALL conditions. That said, there HAD been a proposal to generate electricity by surrounding blast furnaces and such with blankets of thermocouples (this was one of Khruschev's pet projects), but nothing came of it because the capital costs would have been too high and the power generated too small. 24.5.122.13 (talk) 02:05, 28 July 2014 (UTC)

See RTG and this article for practical examples of thermoelectric generators. However, these all use the thermoelectric effect (with dissimilar metals), rather than the electricity generated by heat in a single homogenous component. Tevildo (talk) 07:50, 28 July 2014 (UTC)

Odd cat behavior

Unlike dogs, which wag their tails when happy, cats normally wag their tails when angry. But I know a cat that wags it's tail when happy, for example, when being petted and purring. So, how rare is this ? Do cats raised with dogs pick up this behavior from the dogs ? StuRat (talk) 14:16, 25 July 2014 (UTC)

Cat's have different ways of moving their tails. Some mean that they are happy, some mean that they are annoyed. Just part of the enigma of having a cat share its home with you. [11] ---- CS Miller (talk) 14:36, 25 July 2014 (UTC)

Our cat is almost constantly twitching its tail, whether it's happy, uncomfortable, impatient, or whatever. I think it just likes twitching its tail. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:25, 25 July 2014 (UTC)

There's more than one way to wag a tail of course. When my cat is getting perturbed, it swooshes its tail side to side in very quick motions; when it's in attack mode, the tail lays more or less straight but quivers; when it's happy and relaxed, the tip often curls about like someone keeping time to slow music. It also seems that cats have a particular mood where they're contented but very close to getting extremely pissed off; in those case, my cat both purrs and swooshes his tail "angrily". Continued petting in those cases might lead very quickly to a bite while backing off calms down the tail. Matt Deres (talk) 15:49, 26 July 2014 (UTC)

MSF and Scotlands free ride

If Scotland vote for independence, will the MSF transmitter be moved back to central England (Rugby) like it was before? I assume it was moved up north to give better coverage over Scotland so if they are independent, why cant they build their own time reference and stop riding on our backs for free?--86.171.5.136 (talk) 16:03, 25 July 2014 (UTC)

I never knew that the Multi-Stage Flash desalination process required any sort of transmitter! But yes, if Scotland declares independence, they'll no doubt have to build their own desalination transmitters (whatever that is)... 24.5.122.13 (talk) 17:20, 25 July 2014 (UTC)

. (EC) Questions begining with "I assume" (or for that matter "if") are rarely good questions for the RD. Most sources about the move e.g. [12] [13] [14] mention the move of Time from NPL (MSF) to Anthorn Radio Station was a result of changing the contract from BT to VT Communications (which occured concurrently with an upgrade meaning less maintenence) and don't mention at at all about Scotland or coverage which is kind of weird if that was the intention. Particularly since from what I can tell, these come from before the SNP 2007 Manisfesto was published so I'm not sure there would even be much controversy then. Plus a quick search doesn't find anything 'anthorn NPL scotland' so it doesn't seem likely it was said much by anyone. So basically you're making a claim which few people involved seem to have said which is very weird given the reasoning you claimed. Note that in case there's any confusion to other respondents, the transmitter remains in England, just a different part. Nil Einne (talk) 17:22, 25 July 2014 (UTC)

Well certainly the move to Anthorn has reduced signal strength in most of England, so why was it moved to a central part of the island as a whole if it was not to benefit the Scots?--86.171.5.136 (talk) 17:34, 25 July 2014 (UTC)

Um did I not already say quoting 3 sources? Or do you really need a link to Pound sterling and free market as well? In case you're still confused, you are of course nominally correct. Since Scots must (currently) pay for NPL in some way, just the same as those in Northern Ireland, England and Wales it was ultimately intended to benefit them, just as it was ultimately intended to benefit the people of NI, England and Wales. But not in excess proportion (actually since I suspect England pays more on average for the NPL, because amongst other things they probably use it more on average, it was probably intended to benefit England more. Sort of. Nil Einne (talk) 17:40, 25 July 2014 (UTC)

Sorry, you lost me there. care to explain?86.171.5.136 (talk) 17:47, 25 July 2014 (UTC)

After EC. Your answer makes sense now.86.171.5.136 (talk) 17:48, 25 July 2014 (UTC)

Just from curiosity... how well can you synchronize time over the Internet? I've done a few traceroutes long ago and I know that transit times are variable, but if you choose the right routes to analyze simultaneously, and have a network of a few thousand users' computers analyzing the results after the fact for each experiment, I'd think you could get something pretty precise. I feel like this MSF service ought to be obsolete already. Wnt (talk) 00:11, 28 July 2014 (UTC)

The MSF signal is mainly used as a frequency standard, rather than a time standard. The GPS frequency standard is an alternative, but MSF is still a useful backup. Tevildo (talk) 07:53, 28 July 2014 (UTC)

Would a "mirrored" human body work?

Hi. A 2-dimensional surface with an R on it can only be made to show an Я if rotated in 3-space; similarly, a 3D cube with R on the sides can only show an Я if rotated in 4-space. H G Wells wrote The Plattner Story, in which a man passes through a fourth dimension and returns with his body mirrored: the heart is on the right-hand side, his eyes are reversed, and so on. Suppose that this actually happened to a person: could they still live and function normally, or are there reasons (perhaps e.g. Stereoisomerism) why they could not? Thanks. 86.136.110.44 (talk) 17:25, 25 July 2014 (UTC)

There is a physiological condition where the internal organs are reversed, the name of which escapes me. Slightly shorter life experience is noted in those with it, but that might be because pain localises to the wrong side of the body, making diagnosis harder. 92.40.248.127 (talk) 17:56, 25 July 2014 (UTC)

His body would have the wrong chirality of amino acids, so I don't think he would get the proper nutrition from normal food. Chemical chirality in popular fiction covers some other stories where this happens. Katie R (talk) 18:06, 25 July 2014 (UTC)

Having all molecules mirrored, it seems perfectly feasible that perfect mirroring would produce a fully functional being, since physics is almost exactly symmetrical (there are subtle asymmetries, e.g. in the weak interaction, but I expect that this would have no effect at the chemical level and above). Katie's point about nutrition is of course valid: a source of chemically mirrored food, not only amino acids, would be necessary. For example, the stereoisomer of vitamin C is useless to the human body. —Quondum 18:51, 25 July 2014 (UTC)

Might it be useful to the mirror image of a human, though? ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:43, 25 July 2014 (UTC)

Yes, the R-ascorbic acid would be exactly what the mirror image body would need, and our normal L-ascorbic acid would be useless to it, just as R-ascorbic acid is useless to us. —Quondum 22:00, 25 July 2014 (UTC)

Wow, I can't believe "Chemical chirality in popular fiction" is an article. WP really has everything. Thanks for that. 86.136.110.44 (talk) 22:24, 25 July 2014 (UTC)

Yeah, that one's on my list of favorite article titles now. List of animals with fraudulent diplomas is still my favorite, although I preferred it when it was "cats" instead of "animals." I agree with Quondum that there aren't any fundamental reasons a mirrored body wouldn't function. 3D movies wouldn't look right unless they put the glasses on upside-down, but that's a pretty minor problem. :-) They might also have trouble writing at first. Katie R (talk) 13:53, 28 July 2014 (UTC)

CATS: "All your degree are belong to us" ? - ¡Ouch! (^{hurt me} / _{more pain}) 07:58, 29 July 2014 (UTC)

Or actually the movies probably would be fine... This is confusing to think about. Katie R (talk) 13:54, 28 July 2014 (UTC)

It would depend on whether somebody is born mirrored and grows up that way (their 3d perception would be fine) or you have an adult who is suddenly mirrored. All their 3D perception, not only 3D movies, would be screwed up, because their "right" eye is now their left eye and vice versa. A real-life example of nausea fuel. It could be remedied with 3D TV, by wearing a mirrored version of the 3D glasses, but nowhere else.

OTOH, if everything (in Treknobabble, "down to quantum level") is mirrored, their memories would be mirrored, too. They would think everything else (writing etc) was mirrored; however, their 3D perception would be fine.

Although I'm not 100% sure about the latter; there are certain asymmetries at the quantum level, which would mean that particle A could become particle B when mirrored, and other assorted nastiness. - ¡Ouch! (^{hurt me} / _{more pain}) 07:58, 29 July 2014 (UTC)

Yeah, being born and raised that way would be fine. I have trouble thinking through what the exact effects would be on an adult. If you tried to turn your head right, would it turn left? Would it turn right, but your mirrored vision makes it seem like you're turning left? Is your stereoperception reversed or not? I hadn't really thought of structure below the chemical level. What would reversing the spin of every particle do? Katie R (talk) 11:44, 29 July 2014 (UTC)

See "Situs inversus".—Wavelength (talk) 18:08, 25 July 2014 (UTC)

Note that that condition involves reversal of the organs from right to left, but no change at the molecular level. StuRat (talk) 00:36, 26 July 2014 (UTC)

Flatfish have already evolved a 90° rotation of one eye to join the other "topside" eye. This could have occurred (may still be occurring) in either direction. If a single human should suddenly reverse his Chirality it would cause a ±180° Angular momentum problem that doesn't rate a Wikipedia article. 84.209.89.214 (talk) 18:33, 25 July 2014 (UTC)

• Technical Error, Arthur C. Clarke, 1950. Wnt (talk) 02:20, 26 July 2014 (UTC)

Mediterranean & South China Sea poles of inaccessibility?

Where are the Mediterranean and South China Sea poles of inaccessibility (points farthest from any land above the surface) and which one is farther from that land?Naraht (talk) 18:22, 25 July 2014 (UTC)

I doubt that reliable sources for this question will be found, so I'm going to attempt the forbidden Original Research instead. It's easy to get an approximate answer to this sort of question by just moving a circle (cut out or drawn on thin paper) over a map, provided that it is large enough in scale to show all relevant islands. (It would be useful if the map showed water depths so you could be sure you weren't missing an island, but I'm going to use Google Maps, which doesn't.) If you make the circle the right size, you just need to place it so that you can see by eye that it's equidistant from three points of land in different directions, not all on the same half of the circle, and that nowhere else you put it has the points of land so far away. (For geometrical reasons the desired point will always be equidistant from three points in that manner.) After a bit of experimenting in Google Maps, I find that in the Mediterranean the point 35.15°N,18.45°E seems to be near the correct answer, about 340 km from the nearest points of Italy (at Pachino, south of Syracuse), Greece (at the island of Schiza), and Libya (at Tocra, east of Benghazi) and somewhat farther from Malta and from western Libya near Misrata. The South China Sea is tougher because there are so many different groups of islands, but my best attempt is 18.45°N,117.95°E; this is about 260 km from the island of Luzon, Philippines (at Cabugao, south of Laoag) and from two islands whose names Google Maps doesn't have (one of those is C-shaped, probably a coral atoll, one at about 20.6°N,116.9°E; the other is round, one of the Zhongsha Islands, at about 16.3°N,116.7°E). Hope this helps. --50.100.189.160 (talk) 06:30, 27 July 2014 (UTC)

Thank you. Trying to get a feeling for in a fictional story whether the Mediterranean for our World War II or the South China Sea in this story (France doesn't fall, Italy stays out) would be more "cramped" for World War II era combat.Naraht (talk) 21:23, 27 July 2014 (UTC)

@Naraht: Reading about Operation Pedestal may help to give an idea of how the physical size (or lack of it) of the Mediterranean affected World War II style naval combat operations. In particular, the conditions were ideal for the use of torpedo boats, E-boats, and land-based air attack. They also made naval mines a greater threat, and indeed submarines, although of course the submariners' own escape would end up being more tricky as well. There's still a fair bit of sea out there though; plenty to have survivors of sunken ships bobbing around in the water for a few hours before being rescued by other ships from the same side, then going on to assist other crippled ships from the same side, and so forth.

Another significant difference from the war in the Pacific and (to some extent) Atlantic was that, in the Mediterranean, rather than seeking out an enemy fleet or convoy and then throwing everything you had at it in a strike which would largely either be decisive or not, in a number of the Mediterranean convoys, including Pedestal, the attacking Axis air forces would find and attack the convoy with everything they had, but if that attack failed, the available sea space was sufficiently limited that they would still have a very good idea where the convoy was (unless it turned back), so could basically re-fuel, re-arm, and attack repeatedly - for days on end - until they either ran out of planes or the convoy reached Allied land-based air cover. --Demiurge1000 (talk) 19:07, 28 July 2014 (UTC)

Fusion > Fission?

Will nuclear fusion deliver the era of almost limitless, almost free energy that fission promised but didn't deliver? --129.215.5.255 (talk) 20:39, 25 July 2014 (UTC)

This is a request for speculation, so isn't really answerable. See Fusion power for our article. Tevildo (talk) 20:51, 25 July 2014 (UTC)

Well, it definitely makes for more destructive bombs, if that's considered a plus. ←Baseball Bugs ^{What's up, Doc?} carrots→ 20:55, 25 July 2014 (UTC)

So at the very least it's a possibility which cannot be immediately discounted? --129.215.5.255 (talk) 21:36, 25 July 2014 (UTC)

The sun is a naturally-occurring fusion reactor which provides us with effectively limitless energy. It can't be controlled any more than the H-bomb can, but at least its energy can be captured. I'm curious to know what promises fission failed to deliver upon? ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:41, 25 July 2014 (UTC)

I'm not interested in the Sun! I'm interested in terrestrial fusion reactors. Atomic age discusses fission's broken promises. 129.215.5.255 (talk) 21:54, 25 July 2014 (UTC)

The electricity too cheap to meter was just marketing hype, it was not the serious belief of the engineers. From the Electrical Engineer's Reference Book, Malloy, Say and Walker 6th ed. 1952, I see that an atomic power station is estimated to cost 4 times as much as a coal-fired plant, and it is estimated that the energy will cost 25% more than that from coal. There were other reasons for nuclear power: diversity of supply (necessary to keep the miners in their place), gaining the technological expertise, obtaining fissile isotopes for weapons and national prestige. --catslash (talk) 23:37, 25 July 2014 (UTC)

That's interesting: Too cheap to meter related to fusion all along; people just assumed it referred to fission (and I still did 60 years later). Amazing what you learn on WP. --catslash (talk) 23:53, 25 July 2014 (UTC)

The idea of anything being too cheap to meter seems faulty. Tap water is pretty darned cheap, yet we still meter that. If we didn't, people would waste it to such a degree that it would become a major expense. Same is true of energy. There are all sorts of wasteful things you could use an unlimited amount of energy to do, and if people didn't have to pay for it, they would do exactly that. StuRat (talk) 00:42, 26 July 2014 (UTC)

There are lots of services where the amount that people are charged in/by one city/country/company or another is not related to usage. Tap water is in fact one of them; others include telephone calls, health care, emergency services, garbage collection, and Internet usage. The idea is as logical for electricity as for any other plentiful resource, and in the case of electricity, a limit is imposed on any particular customer by the wiring feeding their home or office. --50.100.189.160 (talk) 08:20, 26 July 2014 (UTC)

I'd be interested to know if runaway usage is a problem where tap water is free. I've wondered the same thing about unlimited phone calls or internet usage. I'd expect some to take advantage and abuse those privileges. For the others, those aren't the kind of things where you can abuse them as easily. You can't just produce a cubic mile of garbage, for example. Perhaps in the case of a hypochondriac they might manage to overuse medical services, and ambulance services do sometimes seem to be overused by those who just can't get a ride for their regular medical appointments, but there they can just charge for nonemergency usage.

And I still insist that un-metered electricity just makes no sense. People would do stupid things like leave their window open in winter in rooms that are overheated by their electric heating unit. Of course, there could be a limit placed on usage just due to the fact that the wires can only deliver so much electricity per house, and that might make it work, even if technically "un-metered", provided something limits usage below the level that would make the wires melt. There are many unwritten limits, too. For example, I found out my car insurance had a limit of 5 tows per year, when I had a rather defective car and they canceled on me after that many. They never stated that in any of their communications. StuRat (talk) 09:52, 26 July 2014 (UTC)

• If the resource is plentiful enough, that kind of "stupid thing" is not important. You persist in thinking in terms of real life instead of embracing the "too cheap to meter" ideal. --50.100.189.160 (talk) 21:08, 26 July 2014 (UTC)

A confident technical prediction does not necessarily give an infallible socio-economic prediction. Thomas Edison predicting development of the light bulb said "We shall make electricity so cheap that only the wealthy can afford to burn candles."[15] 84.209.89.214 (talk) 13:27, 26 July 2014 (UTC)

Isn't that essentially true? Candles are essentially luxury items now - while I suppose you can try to read for a few hours by the light of a 50-cent candle, even conventional light bulbs were something like $5 a month, and the high efficiency ones are only a fraction of that - for much more light and no fire risk. So I'd call this one "confirmed". Wnt (talk) 19:19, 26 July 2014 (UTC)

It may be nearly limitless (as close as infrastructure allows), but it certainly won't be free. Like with fission, the majority of the cost will be the capital costs of building the power plant, rather than the fuel. Whichever design ends up being used, a fusion reactor will be an extremely large and complicated device requiring expensive components like superconducting magnets or huge capacitor banks. ITER is expected to cost €15 billion. It's a research device designed to work out the best design, so "industrial" reactors will (hopefully) be cheaper. But they will still be extremely expensive compared to a natural gas turbine. Maybe in 100 years the technology won't be so exotic and it won't cost very much. But the materials and time required to build it will still have a non-zero cost. The main benefit to fusion is that it's "clean." The main byproduct is helium. Some of the reactor components will be made radioactive by the neutron radiation produced, but the half-lives will be much shorter than spent fission fuel. And it would require less physical space than other "clean" power methods like solar or wind while being able to produce a consistent amount of power. Mr.Z-man 15:03, 26 July 2014 (UTC)