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October 12[edit]

New Earth Like Planets[edit]

General question, The knew possible earth like planet reported in the news could be covered in water, with the current scientific methodology if this is so could we also assume it would have an oxygen rich environment or can water exist in fluid form with out producing any oxygen? 5.175.72.42 (talk) 09:19, 12 October 2016 (UTC)[reply]

We can't assume it has oxygen rich environment just because it has water. Our atmosphere is oxygen rich because early life on earth produced lots of oxygen. Fuortu (talk) 10:06, 12 October 2016 (UTC)[reply]

See Great Oxygenation Event. The Earth's atmosphere contained very little oxygen for the first quarter of its existence (despite the presence of the oceans). Tevildo (talk) 18:00, 12 October 2016 (UTC)[reply]

Is it possible through current scientific methods to see the makeup of the environment...as we do with in our solar system or is the exo-planet to far away? an aded question i know sorry. — Preceding unsigned comment added by 5.175.72.42 (talk) 11:14, 12 October 2016 (UTC)[reply]

An oxygen atmosphere can be abiogenic, if hydrogen is stripped away from the planet by solar wind. With the flare activity of young red dwarfs, this doesn't seem implausible. See Habitability of red dwarf systems for a mention of this. Here is the original paper: [1] Note it is simulation of a range of possibilities and doesn't actually say much. Wnt (talk) 11:45, 12 October 2016 (UTC)[reply]

We can often estimate an exoplanet's mass and orbit size by observing the motions of its host star. That, plus the brightness of its host star is enough to get a rough idea about its surface temperature (if one assumes it is a rocky planet). That gives us a clue about whether it might possibly be habitable for earth-like life. If the planet happens to pass directly in front of the star from our point of view, it is also possible to estimate the composition of the atmosphere by the nature of the small changes observed in the star's light during the time the planet is passing in front. Most planets don't happen to have orbits that pass in front of their host star. As far as I know there is no feasible way right now to learn about an exoplanet's composition if it doesn't happen to pass in front of host star. Dragons flight (talk) 12:09, 12 October 2016 (UTC)[reply]

Tevildo's link above is the most relevant. Once photosynthetic organisms started producing carbohydrates and O2 from water and CO2; the oxygen they released was highly reactive, and it took millions of years for the oxygen and free iron dissolved in the oceans to "rust out" before O2 could accumulated in the atmosphere.

Super earths might be very tectonically active, still producing free iron long enough in their lifetimes to prevent the buildup of an O2 rich atmosphere even when we had long developed one. Hence the lack of free atmospheric O2 would not mean the lack of organisms producing it. The key in finding life will be whether the atmosphere is in a long-term chemical imbalance of some sort.

This book, [pubs.acs.org/doi/abs/10.1021/ed068pA112 The elements, their origin, abundance, and distribution (Cox, P.A.)] addresses the matter at length in its treatment of the atmosphere. μηδείς (talk) 00:26, 16 October 2016 (UTC)[reply]

Regenerating a li-ion battery?[edit]

Is it possible to regenerate a li-ion battery that has degraded due to normal use (that is, several cycles of charging and discharging)? I suppose the wikihow solution of putting the battery in the freezer does not help. However, is there an industrial scale refurbishing of old batteries? Maybe not for small smartphone batteries, but for hybrid/electric vehicles. --Llaanngg (talk) 10:23, 12 October 2016 (UTC)[reply]

Battery recycling generally involves taking the battery apart, melting down the components to separate out the valuable metals, and then using the resulting materials to build new batteries. At industrial scales, such recycling is often cheaper than buying freshly mined raw materials. However, that's not really a "refurbishment". As far as I know there is no simple process to restore the longevity of a li-ion battery. They degrade due to chemical and physical changes in the battery itself and I am unaware of any method of reversing those processes that doesn't involve scraping the battery. Dragons flight (talk) 12:17, 12 October 2016 (UTC)[reply]

(ec) The article Li-Ion#Battery life describes a variety of different ways that these batteries can degrade and there is no way to reverse them all. It is true that their life is longer if kept at low temperature and if a battery management system prevents operation outside each cell's safe operating area (max-charge, min-charge, safe temperature range). Experiments in reviving Li-Ion batteries by methods that have been suggested, such as "zapping crystal dendrites away with an electric welder" (that has been proposed to treat Nicad batteries that have an unrelated chemistry) are too dangerous due to the documented liability of Li-Ion batteries to explode. Thus the only option is to replace degraded Li-Ion battery cells with newly manufactured ones. Ideally old Li-Ion batteries should be recycled to recover their elements including iron, copper, nickel and cobalt but not much has been invested into recycling Li-ion batteries due to costs, complexities and low yield. AllBestFaith (talk) 14:28, 12 October 2016 (UTC)[reply]

"Several" discharge cycles should have no effect on the battery; it should take several hundred cycles at least for any noticeable loss of charging capacity. If you were being literal, and you have a battery that is new, it's defective and you should return it if it's under warranty. --47.138.165.200 (talk) 19:43, 12 October 2016 (UTC)[reply]

With "several" I meant enough wear and tear under normal circumstances to reduce its capacity, but nothing that would be covered by a warranty. Llaanngg (talk) 17:12, 13 October 2016 (UTC)[reply]

What's the Maximum cruise speed for Boeing 767 at 5000 ft?[edit]

And what's happening when the plane pass the cruise speed? 37.142.197.179 (talk) 12:51, 12 October 2016 (UTC)[reply]

Wikipedia has a general article on Cruise (aeronautics) which covers some of the general concepts, such as how optimum cruise speed is arrived at. That may help some with your second question. --Jayron 32 13:01, 12 October 2016 (UTC)[reply]

The normal cruising height for a large jet is above 30,000 feet. At 5,000 feet the plane will have difficulty reaching its normal cruising speed. Wymspen (talk) 13:24, 12 October 2016 (UTC)[reply]

14 C.F.R. §91.117 (a) Aircraft Speed states: "Unless otherwise authorized by the Administrator, no person may operate an aircraft below 10,000 feet MSL at an indicated airspeed of more than 250 knots (288 m.p.h.)." (These rules apply in the United States, but generally, almost all other nations have similar or stricter requirements).

If you happened to be near San Francisco this week, you might have seen a United Airlines 747-400 operating low and slow - here's a video of Saturday's show. The aircraft maneuvered below 5000 feet MSL at speeds between 145 mph and 300 mph (with special approval from the FAA).

A large airliner like a 747 or 767 is not designed to operate efficiently at cruise configuration at 5000 feet MSL - but it is capable of flying in that configuration.

In normal cruise flight, a 767 is operating at or below V_NO. That means its flaps are up, its gear is up, and its multiple engines are configured for long-term, efficient flight; and it is not making any abrupt control surface deflections.

Nimur (talk) 15:53, 12 October 2016 (UTC)[reply]

Had the pilots of El Al Flight 1862 known what was going on, they would have had a shot at a survivable outcome by dumping more fuel and then attempting a landing at a speed of around 200 knots. Count Iblis (talk) 17:34, 12 October 2016 (UTC)[reply]

Sorry, but... ^{[citation needed]} ? Do you make this claim because a reliable source - like the post-crash investigation report - indicated that the accident would have been survivable if the pilot(s) had done something differently? Because... if not, you probably shouldn't repeat that kind of a ludicrous claim on our encyclopedia, especially if you aren't an expert in the detailed analysis of 747 accidents.

After a major aviation accident that involves such great loss-of-life, experts study the event in great detail and publish their findings. If it is determined that different pilot-decision-making could have saved lives, that type of important detail gets published, and usually gets incorporated into training material. I do not believe any reputable accident-investigator believes that El Al Flight 1862 could have been made survivable if the pilots had made different decisions.

A detailed analysis of crew decision making is included in Chapter 2.5 of the Nederlands Aviation Safety Board AIRCRAFT ACCIDENT REPORT 92-11, available in English from archive.org. There is no mention whatsoever that Count Iblis' proposal - which does not even comply with the emergency-operations procedures for a 747 - could possibly have made the situation work out any better. Specifically quoting the accident report: "the possibility for a safe landing was highly improbable, if not virtually impossible" - even if the pilots had done something differently. That's the official, published opinion from a team of aviation experts - who specifically studied the accident - and know far more than you and I about 747 operations.

This is Wikipedia - the free encyclopedia that anyone can edit - but we have a standard for sourcing our claims. Just like you can't make up random numbers and facts about general science and post them in our articles, you should not post procedures, airspeeds, or analyses, if you don't know them and can't cite sources for them.

Nimur (talk) 18:09, 12 October 2016 (UTC)[reply]

See here: "The analysis indicates that the accident aircraft was recoverable from a technical point of view. However, the required procedures to perform such a recovery are not part of current industry training practices for complex in-flight emergencies or handling qualities in degraded modes. It is therefore understandable that a successful recovery of the aircraft was highly improbable." Count Iblis (talk) 19:10, 12 October 2016 (UTC)[reply]

Thank you for citing a source. At least we can now attribute the claim, irrespective of my personal opinions about that claim.

The author of the conference-paper you cited, M.H. Smaili, has his entire thesis available at this link, hosted by Netherlands Aerospace Centre: NLR-TP-2003-392 Flight data reconstruction and simulation of the 1992 Amsterdam Bijlmermeer airplane accident. It is worth consideration. I read most of the 40-some pages, and it is true that the author of that paper does recommend your idea, including a fuel jettison and a "high-speed landing or ditch at 200/210 KIAS", and also acknowledges that this recommendation is in contravention of the ordinary emergency operating procedure.

Even still, the source you cite is a student's thesis (abridged into a conference-paper presentation). Here's my two cents: pilots should not turn to students for advice on how to fly damaged aircraft. Even very smart people - who work out math very carefully, and perform elaborate simulation - are not necessarily qualified to provide advice or instruction on the safe operation of an aircraft in any condition. The author even admits that the procedure he recommends deviates from the procedure that industry-experts recommend. For example: here are a few bits of techno-babble that you might have lost in the details: "Weight reduction was achieved by simulation of fuel jettison up to a remaining quantity for about 20 minutes of flight." "Further speed reduction below approximately 220 KIAS at flaps 1 resulted in a loss of go-around capabilities." Are you - or the author - qualified to evaluate that statement to determine the impact of those consequences? Do you believe that you could make the judgement-call between one statistically-unsafe outcome, and another, different, statistically-unsafe outcome? (For example: do you know whether it is safe to jettison fuel on a Boeing 747 when the cockpit instruments are indicating an engine fire? Do you know whether there is enough precision to dump the correct amount of fuel when an aircraft is damaged in this way? What if you inflame the fire and blow up a wing? What if you jettison all your fuel and lose all propulsion? You just made your catastrophic emergency into an even worse catastrophic emergency!) This is exactly why pilots are highly trained to follow standard procedures, even during catastrophic emergencies.

In this case, I would defer to the accident report, which found that safe control of the aircraft was a virtual impossibility.

Here's a life-tip: Go Fly. During the pre-flight brief, ask your flight instructor to demonstrate an emergency-procedure during your first flight. It will change the way you think about aviation safety. Because, at some random time during the flight, probably while you are out sight-seeing and having a great time, the instructor will simulate an emergency and do something with a small airplane that will scare the lights out of you. Surprise! You're a mile from earth and don't have an engine! How will you react?

Demonstrating, and practicing, and preparing, for emergency operation is a very normal part of flying and flight training. Just a few weeks ago, I practiced something like five or ten emergency-landings. You can even listen to me having a pleasant conversation with our air traffic controller as I repeatedly kill the engine. This stuff has to be beaten into your head during practice flights so that you do it right when you're in a real actual emergency. Don't panic. Follow the checklist. Definitely don't try anything new.

Nimur (talk) 19:19, 13 October 2016 (UTC)[reply]

Caterpillars and butterflies[edit]

Here it says that butterflies are "able to remember the solution to a puzzle that they were taught how to solve when they were a caterpillar". How can you teach a caterpillar how to solve a puzzle? How can you even teach ANYTHING to an animal as inferior as a caterpillar? --Qnowledge (talk) 16:13, 12 October 2016 (UTC)[reply]

Insect nervous systems may be quite primitive, but that doesn't mean they don't have a capacity for learning. This source may be helpful. NorthBySouthBaranof (talk) 16:21, 12 October 2016 (UTC)[reply]

Note that the "puzzle" could be quite basic, like remembering that the red leaves are bitter and the green leaves are good. StuRat (talk) 16:39, 12 October 2016 (UTC)[reply]

"...that they were taught how to solve..." Who taught them? ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:07, 12 October 2016 (UTC)[reply]

Invertebrates are very capable of learning quite advanced tasks. I suggest the OP should read Pain in invertebrates#Learned avoidance and Pain in invertebrates#Cognitive abilities. DrChrissy ^(talk) 17:28, 12 October 2016 (UTC)[reply]

These scientists. When volunteering to help at a reference desk, it's a good idea to look for references before posting. It can be hard, so I'll tell you how I did it. I remember reading the work, but forgot who published it and where. So I went to google and typed /caterpillar learn butterfly/ [2]. The top hit is this Wired article [3], and a quick skim of that gave me an author name, Weiss. Now it's just another click over to google scholar, where I typed /weiss caterpillar learn/ [4], where the mentioned PLoS ONE article is the second hit. That's how you can help provide references on the reference desk. It took me longer to type this up (~3 minutes) than it did to find the answer for OP (<1 minute), but I hope that helps. SemanticMantis (talk) 17:42, 12 October 2016 (UTC)[reply]

The famous recent work on ~~butterflies~~ Lepidopterans remembering what was learnt as a caterpillar is Blackiston et al. (2008) "Retention of Memory through Metamorphosis: Can a Moth Remember What It Learned As a Caterpillar?" [5] It explains in the abstract:

“

Fifth instar Manduca sexta caterpillars received an electrical shock associatively paired with a specific odor in order to create a conditioned odor aversion, and were assayed for learning in a Y choice apparatus as larvae and again as adult moths.

”

The paper is freely accessible, and include diagrams of the puzzle/challenge setup. SemanticMantis (talk) 17:37, 12 October 2016 (UTC)[reply]

Other examples of memory and learning surviving metamorphosis include -[6][7][8] DrChrissy ^(talk) 22:43, 12 October 2016 (UTC)[reply]

As described, this does not necessarily have to mean the nervous system carries the memory. Most notably, aversive associations have been reported to be passed on in mice through two generations. [9] I would take a guess that this involves the epigenetic alteration of specific genes closely associated with the odor reception itself, though I don't know that - what I do know is that spermatozoa don't have brains. :) Wnt (talk) 15:45, 13 October 2016 (UTC)[reply]

Yeah, the second generation mouse "memories" together with the trans-pupation "memories" form a captivating picture. You're right that sperm don't have brains, but structural content for the moths could conceivably be preserved in the Imaginal discs. SemanticMantis (talk) 16:28, 13 October 2016 (UTC)[reply]

I have traced the mouse study back to its original source here[10]. Rather oddly, hidden away in the text is a statement that pups born by artificially insemination were not behaviourally tested. This, to my mind, makes their statements dismissing observational learning as weaker than might be perceived. DrChrissy ^(talk) 17:01, 13 October 2016 (UTC)[reply]

User:DrChrissy Interesting, thanks. Are you suggesting that parents could some how teach pups odor aversion even when not they are exposed to the odor simultaneously? I don't think the mothers were challenged with the odor while pregnant, so that rules out in utero "observation," right? Maybe I should just dig into the design/protocol myself but I'm curious what you're getting at. SemanticMantis (talk) 19:01, 13 October 2016 (UTC)[reply]

Ah - I have just seen that in the cross-fostering study, the pups were fostered On Day 1 postnatally. This means there would have been very, very limited opportunity for observational learning. And you are correct the females were not (deliberately) exposed to the odour while pregnant. DrChrissy ^(talk) 19:30, 13 October 2016 (UTC)[reply]

Human travel to Mars[edit]

How are we going to shield the astronaults brains from radiation?--86.187.174.75 (talk) 17:34, 12 October 2016 (UTC)[reply]

Read this. --Jayron 32 17:36, 12 October 2016 (UTC)[reply]

Some good stuff at radiation protection and radiation hardening (though that second one is geared more towards protecting equipment). We don't seem to have a specific article devoted to the subject of protecting astronauts from radiation, but it shows up in a number of other areas. Matt Deres (talk) 17:46, 12 October 2016 (UTC)[reply]

You'll want to shield more than just the brain. Actually, the brain is more radiation-resistant than some other parts of the body, because (especially in adults) it doesn't contain a lot of actively-dividing cells. Human spaceflight and Effect of spaceflight on the human body may be of interest. --47.138.165.200 (talk) 20:13, 12 October 2016 (UTC)[reply]

Whilst you make the certainly important point that the brain is largely post-mitotic, there is still a lot of damage that can be done in the absence of cell division, see our excellent article central nervous system effects from radiation exposure during spaceflight. Fgf10 (talk) 07:00, 13 October 2016 (UTC)[reply]

I'd say start here: [11]. It is possible to take a portion of the radioresistance of tardigrades and put it into human cells, allowing for the possibility of gene therapy or other penetrating treatments getting Dsup to where it could protect the DNA directly. Wnt (talk) 15:48, 13 October 2016 (UTC)[reply]

Purported car that runs on sea water[edit]

I came across this recently which appears to boast that their car can run on ordinary sea water. It sounds bogus but I wanted to confirm with the experts here. This is bs right? ScienceApe (talk) 18:53, 12 October 2016 (UTC)[reply]

Yep, total bs, more precisely some mix of pseudoscience, hoax, and fraud. We have a pretty good article on water-fueled cars that explains the problems and some history, Snopes is also always a good place to check for this kind of thing. They don't seem to have a full article but their discussion thread on the topic is here [12]. SemanticMantis (talk) 18:58, 12 October 2016 (UTC)[reply]

(Sorry, I flubbed this one by skimming the source link too quickly and jumping to conclusions. Best to ignore my whole post.) SemanticMantis (talk) 03:16, 13 October 2016 (UTC)[reply]

It not purported to run on seawater, that is merely what the journalist described it as. No, in fact the nanoFlowcell is described by its inventor as running on "bi-ion liquids" which he claims was conceived by NASA decades ago (though I can find no evidence of this). If you read his description, it sounds like a relatively ordinary battery, and the water is simply the solvent for the electrolytes. If you buy his description of how it is supposed to work, the advantage of this over an electric car is that instead of recharging the battery, you simply refill the emptied electrolyte tanks. If it worked, that would certainly be a lot faster than recharging. The one part of the description that sounds extremely fishy is the inventor's claim that one side contains a positive charge, and the other contains a negative charge. Two tanks of water separated by a membrane doesn't seem like an especially good capacitor, so that doesn't seem like a winning design for a car battery. We can give him the benefit of the doubt and assume he's talking about the general way that batteries work, with chemical reactions continuously generating positive charges on one side and negative charges on the other. This description is too vague to violate the laws of physics, but it has other hallmarks of a scam. The biggest red flag is that he is going public with this project while at the same time being extremely secretive about how it works - giving general descriptions but no specifics. In my experience reading about scams, any time someone presents what is basically a magic box that does something revolutionary, but won't let you look inside, it's a scam. And believe me, this car is pretty magical. Battery design is a very hot field, and making a battery light enough to power a car any significant distance is quite a feat. The batteries currently used in electric cars run on some fairly exotic electrolytes in organic solvents or fancy solid substrates, and are the result of decades of research and development. For someone to claim he did it with something he could dissolve in ordinary water is hard to believe. The typical evolution of all of these water-fueled-car scams is to go public with a revolutionary invention, be incredibly vague about how it works so no one can point to a violation of the laws of physics, collect millions of dollars in investments, then disappear into the aether. Someguy1221 (talk) 20:37, 12 October 2016 (UTC)[reply]

I erroneously jumped to the conclusion this was the same old junk. In fact it seems to be merely conceptually similar junk, so thanks for clarifying :) SemanticMantis (talk) 21:24, 12 October 2016 (UTC)[reply]

Flow batteries are commercially available and in use worldwide. Vanadium pentoxide, from memory. Greglocock (talk) 22:12, 12 October 2016 (UTC)[reply]

We apparently haven an article on flow batteries, and apparently a number of laboratories are trying to develop ones suitable for cars. Someguy1221 (talk) 22:19, 12 October 2016 (UTC)[reply]

Any student who took college chemistry and is familiar with the Nernst equation will also hopefully remember the concept of the concentration cell, of which a flow battery is basically a highly engineered version of. --Jayron 32 22:39, 12 October 2016 (UTC)[reply]

The "water dust" part sounds pretty fishy to me. I don't know what the secret ionic liquids are, but I bet whatever they are if you dump the residue from 150 liters of them on the road pretty often, the ecologists will have something to say about it. I mean, they don't even like road salt, and if this were as easy as road salt you'd think it would have been invented before. Wnt (talk) 15:53, 13 October 2016 (UTC)[reply]

It is also worth noting that if he were a real scientist, he'd use the damn right terms. I suppose he could be talking about some of the more exotic low-temperature ionic liquids, though most actual chemists I know tend to use the term to refer mostly to molten salts. Unless he means simply an aqueous solution of a salt. I'm pretty sure one of the indicators on the Crackpot index is someone who confuses basic terms from the very science he's purporting to be an expert in. --Jayron 32 19:02, 13 October 2016 (UTC)[reply]

Lord, there is a year and a half old Wikipedia article on this dubious Liechtenstein company NanoFlowcell which is asking for investors on its linked to website. Car show flash, and not even close to being enough grit, and perhaps worthy of deletion. --Modocc (talk) 20:08, 13 October 2016 (UTC)[reply]

Acousto-magnetic tags[edit]

This is about acoustto-magnetic tags, particularly about the role of the second "magnetically semi-hard metallic strip". According to the wikipedia article its purpose is to offset the magnetic anisotropy within the first strip, which "makes the [first strip] respond much more strongly".

How exactly does the external field make the response stronger and what does "stronger" mean here?

Somewhere else I read that the second strip provides a "bias" which causes the first strip to vibrate at the same frequency as the external pulse frequency (58 kHz) from the detector. Without the "bias" it would oscillate at twice this frequency.

Is this correct?

bamse (talk) 20:49, 12 October 2016 (UTC)[reply]

There are two reasons for the magnetised strip.

Firstly it's a "switch". By being either magnetised or not, the tag can be turned on or off. This isn't essential for all tags (some are mechanically detached, some are always active but passed around the detector by staff), but it's useful and is used here.
Secondly, it increases the sensitivity of these tags - they may just not be viable devices without. The way it works is that (all?) magnetic devices demonstrate hysteresis: the relation between applied field strength $H$ and resultant magnetisation $M$ isn't linear or even a simple mapping. However if $H$ is increased (by the nearby strip) it shifts the material's behaviour away from the $H=0$ point (the least linear point) to a place where the behaviour between the two is more approximately linear, or at least where the available change in $H$ (i.e. how much the reader's field coils can apply) gives a larger and more easily detectable change in $M$ . Andy Dingley (talk) 21:08, 12 October 2016 (UTC)[reply]

Thanks that argument with the hysteresis makes sense to me. However, unless I misunderstand magnetic anisotropy, this is not exactly what it says in the article, is it? Also what about the frequency argument, is it correct? bamse (talk) 22:29, 12 October 2016 (UTC)[reply]

The frequency argument is correct but Andy Dingley's hysteresis description (though relevant to magnetic recording) is not relevant to the acousto-magnetic tag.

The sentence "The magnetized strip makes the amorphous strip respond much more strongly to the detectors, because the DC magnetic field given off by the strip offsets the magnetic anisotropy within the amorphous metal." was posted by Oosacker[13] and may be challenged. I find no source for it and instead believe this explanation [14]:

"[The acousto-magnetic tag] requires bias magnet material in addition to active element material. The [magnetorestrictive] material will shrink no matter which direction the magnetic field is placed upon it. If the tag is driven with Frequency, F, it gets smaller as the magnetic field increases and larger as it's driven towards zero. This means that while it is being driven at F, the tag is trying to work at 2F, because at both positive and negative halves of the drive signal, the tag is getting smaller. To get the tag to work at F, a bias field is required. The bias is provided by a semi-hard magnetic element in the label. When magnetized, the bias prevents the active element from ever being in a zero field condition. So for an entire half of the drive signal, the tag shrinks. Then it expands for the other half. This results in an F response.

When you walk through the gate with a tag, the transmitter in the gate energizes the material and causes it to resonate at F. The transmitter then stops. The tag will continue to "ring" at F for a short period of time, and the receiver listens for that frequency. If it hears it, it knows there is a tag and sounds the alarm.

When the AM tag is demagnetized, it is deactivated. When it's magnetized, it is activated. (This is the opposite of how the deactivation of EM tags works.)"

The above explanation makes sense and could be rewritten for use in the article. @Oosaker: last posted to the article discussion page in 2008[15] and was aware of the howstuffworks reference. AllBestFaith (talk) 15:58, 13 October 2016 (UTC)[reply]

What's the smallest nm node that's inevitable in consumer electronics (as far as we know)?[edit]

I guess I could wake up in a holodeck on a Discworld in a universe where matter's infinitely divisible at any time so nothing's inevitable but assume that unlikely shocks to civilization like that or a comet ending humanity or something don't happen. 7nm is still not inevitable yet, right? Is 10nm inevitable? When it gets to the point where manufacturers realize a full node is too hard will they start releasing ever smaller percentage shrinks just so the time between nodes doesn't accelerate astronomically or to try to take the asymptotically decelerating record from company X for awhile? Sagittarian Milky Way (talk) 23:40, 12 October 2016 (UTC)[reply]

We actually have articles on these. The 10 nanometer chip appears to be commercially inevitable. The 7 nanometer chip is more iffy, but major corporations are planning to produce them in bulk in the future. 5 nanometer chips and under are still highly experimental and it doesn't look to me like these will be inevitable until some completely new chip technology has matured, after which we'll have to reassess what's possible. Someguy1221 (talk) 23:59, 12 October 2016 (UTC)[reply]

http://www.theregister.co.uk/2016/10/10/boffins_eschew_silicon_to_build_tiniestever_transistor_just_1nm_long/ 196.213.35.146 (talk) 07:47, 13 October 2016 (UTC)[reply]

People may have to use molybdenum disulfide or molybdenum ditelluride or another of the Transition metal dichalcogenide monolayers and graphene to get smaller, but these are still at an experimental stage, and not a technology yet. Graeme Bartlett (talk) 11:08, 13 October 2016 (UTC)[reply]