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December 8

Falling from a balloon

In the opening sequence to The World Is Not Enough, what altitude is the hot-air balloon at when it explodes? Would a fall from this altitude onto a sloped/domed ~~concrete~~ fiberglass roof, as depicted in the movie, be survivable? 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 02:53, 8 December 2016 (UTC)[reply]

There have been reports of people surviving falling at terminal velocity, see Free_fall#Surviving_falls. So I guess it is "survivable" (if the odds do not matter as long as they are higher than 0, and the shape of the survivor does not matter as long as the heart/brain still work). Tigraan^{Click here to contact me} 07:20, 8 December 2016 (UTC)[reply]

OK then, let me put it a different way: As depicted in the movie, how high (or I should rather say how low) are the approximate odds of survival? 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 10:51, 8 December 2016 (UTC)[reply]

Wikipedia has an article and section Free fall#Surviving falls which may provide a starting place for your research. --Jayron 32 11:34, 8 December 2016 (UTC)[reply]

Any place where I can find a table or graph of % chance of survival vs. altitude? Also, how does the slope of the surface affect the chance of survival? 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 11:46, 8 December 2016 (UTC)[reply]

You can be killed in fall when you've got feet on the floor of your house. ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:34, 8 December 2016 (UTC)[reply]

Just watched the relevant clip -- this shows that the altitude is about 60-80 m (definitely less than 100 m, as per the article), and the slope of the roof looks to be about 15-20 degrees -- what are the chances of survival in this case? (Assume the person rolls down the slope rather than just splatting straight down on the roof, as indeed is the case in the film.) 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 13:14, 8 December 2016 (UTC)[reply]

This research paper has a section titled "Tolerance to impact acceleration" that lists some absolute limits; of course freak occurrences happen, but these values probably represent the expected maximum impact velocities for various landing configurations (feet first, head first, etc.) That would certainly help your research. --Jayron 32 14:48, 8 December 2016 (UTC)[reply]

This study directly correlates height with lethality. --Jayron 32 14:50, 8 December 2016 (UTC)[reply]

Thanks! So, possible but unlikely, right? 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 01:10, 9 December 2016 (UTC)[reply]

Beech 18

What is the landing speed of the Beech 18? 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 03:03, 8 December 2016 (UTC)[reply]

It is about 1.3 x stall_speed which is quite complicated to calculate. See also https://flightsafety.org/wp-content/uploads/2016/09/alar_bn8-2-apprspeed.pdf Without knowing exactly which Beech 18 model is hard to say but I would guess around 70-80 knots. I will ask an old-timer pilot I know and post again. 196.213.35.146 (talk) 07:43, 8 December 2016 (UTC)[reply]

There is actually an internet-available flight manual for the Beech 18, circa 1948 [1]. I'll just quote exactly: "Gear, down... flaps, down, maximum speed 120 mph TIAS... Use small amount of power on approach. Approach speed is approximately 105 mph TIAS. Contact speed is approximately 80 mph TIAS." Someguy1221 (talk) 07:55, 8 December 2016 (UTC)[reply]

This account [2] says "just over 90 mph" approach speed which is 78 knots. 196.213.35.146 (talk) 08:08, 8 December 2016 (UTC)[reply]

It also just hit me that there are many variants with different weights and engines, so presumably they could have different landing speeds. Someguy1221 (talk) 09:47, 8 December 2016 (UTC)[reply]

Thanks, all! So, about 80-90 mph, right? And question #2: If someone falls out of the plane as it touches down at that speed, is it possible for that person to survive? 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 10:53, 8 December 2016 (UTC)[reply]

The frequent crashes of professional motorbike riders (in, for example, MotoGP) at similar or higher speeds without major injury suggest that it's certainly possible. They, however, are falling from a fairly low "altitude" (a "highside" crash might throw a rider perhaps 8 feet in the air - a broken collarbone, wrist or lower leg/ankle is likely in such a scenario: searching for such crashes on YouTube is likely to be productive) and are wearing protective leathers and gloves which allow them to slide rapidly on smooth tarmac without friction abrasion (to themselves). Portraying such an incident in a fictional work (which I'm guessing the OP is researching for) might need some careful details in the setup and description to retain verisimilitude. {The poster formerly known as 87.81.230.195} 90.200.136.117 (talk) 12:02, 8 December 2016 (UTC)[reply]

Sure. With the right gear. [3] 196.213.35.146 (talk) 11:55, 8 December 2016 (UTC)[reply]

I meant falling at the moment of touchdown (i.e. from just above ground level, as in the motorbike scenario), but without any special gear, like in this video -- would the secret agent get killed, or would he just break every bone in his body? (Also note that in the video I linked, the plane touches down at well above normal landing speed, as evidenced by the fact that it has its flaps up and that it bounces hard -- how would that affect the chances of survival?) 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 12:32, 8 December 2016 (UTC)[reply]

African or European Beech 18? --Jayron 32 15:23, 8 December 2016 (UTC)[reply]

Whichever one Kamal Khan has. 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 06:17, 9 December 2016 (UTC)[reply]

Why defibrillator is not placed directly above the heart?

One might think that the manual external defibrillator's direct placement of paddles above the heart is more efficient than the currently used placement. Thanks.--93.174.25.12 (talk) 09:49, 8 December 2016 (UTC)[reply]

There are different positions in which defibrillator pads can be placed, depending on several factors including the manufacturer's guidelines. It is in fact quite common for one of the pads to be placed over the cardiac apex. (NB I am qualified in advanced life support). — Preceding unsigned comment added by 86.142.162.185 (talk) 10:39, 8 December 2016 (UTC)[reply]

(edit conflict) I have no medical qualifications whatsoever, but I think you imagine that the electrodes send the electricity forward to the heart, and hence it would make sense to place them as close to the heart as possible.

That is incorrect, because the electricity does not "know" it should go to the heart. Put another way: why are there two electrodes? The burst of electricity will flow from one to the other by multiple paths, and will "choose" preferentially the paths with the lowest resistance. Some paths go through the heart, others do not, and your job is to deliver the most of the electric burst to the heart.

If we make the assumption that a path's resistance is proportional to its length, if you place the two electrodes very close to each other, the path of least resistance will be very short compared to diving inside the body to reach the heart and back. If the electrodes are further apart, the detour is shorter, relatively speaking.

All the above is of course extremely simplified. First of all, electrical conductivity varies, probably by a huge factor, within the human body. Moreover, "resistance" should probably replaced by impendance because we are talking about a transient phenomenon. Finally, there might be medical reasons to target here rather than there that have little to do with the electricity. Tigraan^{Click here to contact me} 10:47, 8 December 2016 (UTC)[reply]

All things being equal, the bulk of the electricity will take the shortest path. And the skin can act as a barrier, such that electricity may be conducted along the sweat on the skin, instead of penetrating it. My Dad, who worked in medical electronics, had an invention idea of paddles with small tines that would penetrate the skin, similar to the tine test used for TB, to avoid this problem. Unfortunately, it hasn't caught on yet. StuRat (talk) 15:28, 8 December 2016 (UTC)[reply]

Sleeping positions

While lying in bed recently, I was wondering whether some sleeping positions are more preferred than others (e.g left side, right side, back, front)? Any statistics? In particular, I was reflecting on the fact that I generally prefer my left side over my right. Now this might just be habit, but I was wondering if there might be some advantage to sleeping on one side rather than the other. Since the heart and stomach are both somewhat to the left of center, maybe the left side improves circulation or reduces heart burn or something. I can't say I've ever really noticed a difference per se, but maybe I originally adopted the sleeping preference due to some small difference without really picking up on why. So, any stats on sleeping positions? Or perhaps physiological reasons why some positions might be better / more comfortable than others? Dragons flight (talk) 12:58, 8 December 2016 (UTC)[reply]

Read this. --Jayron 32 13:03, 8 December 2016 (UTC)[reply]

I'd note that despite being a chest sleeper, I nearly always wake up either on my back or sideways. Perhaps subconsciously it's a natural way to get more oxygen (and give some space for occasional morning wood). In any case it's normal to change positions while sleeping. Just don't put your arms under the head or cheek as it will disrupt the bloodflow and nasty feelings will happen. Brandmeister^talk 13:58, 8 December 2016 (UTC)[reply]

Forgive me, but the first half of that linking sleeping positions to personality traits sounds like bad pseudoscience. Maybe the position statistics are correct, but I think I'd need a fairly large dose of peer review to be confident in anything presented with that introduction. Of course, even if accurate, it also doesn't address my right vs. left curiosity. Dragons flight (talk) 15:57, 8 December 2016 (UTC)[reply]

How about this one. --Jayron 32 18:26, 8 December 2016 (UTC)[reply]

(EC). Does this help? Matt Deres (talk) 18:26, 8 December 2016 (UTC)[reply]

LOL, I have a few that aren't on any of these lists. There are two with one knee up - in one, the other foot rests against it forming a tetrahedron, and in the other the foot whose knee is up goes in front of the other leg with bent knee. Wnt (talk) 22:18, 8 December 2016 (UTC)[reply]

Pete AU aka --Shirt58 (talk) 11:54, 10 December 2016 (UTC)[reply]

Well, a graphologists may agree with you that your development stopped at the age of fifteen but what has this to do with sleeping positions? P.S. If you bought this book with the assurance that it would be able to improve your handwriting, I hope you kept the receipt, as you can now (I think) ask the book seller for a full refund. Oh Gosh. Just look at it. It is all sloping down hill, and a lot of letters are not joined up! Further. Can only award you 6 out of 10 for dotting all your is and crossing all your t's, as the t's differ in hight and the dots over your iota's float to too much to the right. Both signify you have closeted liberal tendencies rather than being a plain, unadulterated conservative. ;¬ ) --Aspro (talk) 20:14, 10 December 2016 (UTC)[reply]

I don't agree that your handwriting shows you are highly organized. I should think neat hand-printed letters (or neat cursive), perhaps using a straight-edge to draw guide-lines to keep the text from drooping down on the right side, would be more what I would expect from such a person. Also, I wouldn't expect those stains on the right side (blood, chocolate ?). I have seen much worse handwriting, though. StuRat (talk) 16:28, 11 December 2016 (UTC)[reply]

See "Sleeping position" and Wikipedia:Reference desk/Archives/Miscellaneous/2010 May 1#No article on sleeping positions?

—Wavelength (talk) 20:41, 10 December 2016 (UTC)[reply]

Star formation and Dark matter

It is said that dark matter can be affected by gravitational force. So during the formation of stars dark matter should also be accerted into them. So my question (doubt) is do stars contain dark matter?, if so why?, if they don't why?--G.Kiruthikan (talk) 14:31, 8 December 2016 (UTC)[reply]

The answer for any question you may have about dark matter is "we have no idea". Dark matter is a hypothetical explanation for a plethora of as-yet unexplained phenomena, dark matter has never been directly observed, its existence is likely, but only inferred from other observations, mostly that the observed velocities of distant objects is greater than would be expected from their measurable mass. The most common explanation is that the difference is caused by an undetectable mass which cannot otherwise be accounted for, which we call "dark matter". If we knew what it was, it wouldn't really be "dark matter" anymore, we'd just call it "matter" and describe it. Dark matter is name physicists use instead of unobtanium or some such, because that would sound silly, but otherwise, we don't know much about it, except what effects it has on the movement of large, distant objects (if it does exist and is indeed the cause of such phenomena). --Jayron 32 14:40, 8 December 2016 (UTC)[reply]

As an addendum, just to show that physicists do have a bit of a sense of humor, competing theories of the source of dark matter go by names like Weakly interacting massive particles (WIMPs) and Massive compact halo object (MACHOs). --Jayron 32 14:42, 8 December 2016 (UTC)[reply]

This is a good Q. If dark matter behaves the same way as ordinary mater, with respect to inertia and gravity, then wouldn't we expect a similar distribution ? But the proposed distribution of dark matter is more spread out, into large "halos" around galaxies. So, to me this suggests that dark matter may break the link between inertial mass and gravitational mass we see in ordinary matter. Specifically, it may have a higher inertial mass, making it move more slowly in response to the smaller gravitational pull it is subjected to. StuRat (talk) 15:38, 8 December 2016 (UTC)[reply]

Dark matter do "behaves the same way as ordinary mater, with respect to inertia and gravity" but because it is collisionless it spreads out in large halos. Ruslik_Zero 17:26, 8 December 2016 (UTC)[reply]

Right, even starting from similar initial distributions, you'd expect dark matter (of the WIMP variety) to have different final distributions, given it is basically a collisionless, frictionless, ideal gas, more or less. Someguy1221 (talk) 01:16, 9 December 2016 (UTC)[reply]

Here are a selection of research papers that discuss star formation and dark matter, they may provide some material of interest [4] [5] [6] [7]. SemanticMantis (talk) 17:10, 8 December 2016 (UTC)[reply]

Thank you for some great help. The thing that I can gather is that it has a different distribution. Someone please explain why it has a different distribution? And if it doesn't have any collisions there cannot be any charges (because it is the electrons that repel in collisions) or may be elactrons and protons (or charged particles like them) should lie in the same nucleus. Is my speculation theoretically right that dark matter may be electrons in the nucleus ? I think it may be right because nuclei like alpha can penetrate matter easily (Rutherford's gold sheet experiment). --G.Kiruthikan (talk) 10:15, 9 December 2016 (UTC)[reply]

You are right that dark matter particles have no electrical charge, or at least that is how they are usually modeled (no one has managed to detect one yet). Dark matter cannot be made of electrons and/or nuclear particles because even if the charges balanced, leaving it with a neutral charge, such a particle would still interact with electromagnetic fields. Also, alpha particles do not penetrate matter easily - they can in fact be stopped by a thick sheet of paper. In Rutherford's gold foil experiment, that foil was nanometers in thickness, and still managed to block a detectable number of alpha particles. The lack of interaction with ordinary matter would explain the different distribution of dark matter. Basically, there's nothing slowing it down. No collisions, no friction, no radiating energy by electromagnetism. They would in theory just go round and round the galaxy for billions of years quite happily. Someguy1221 (talk) 10:14, 9 December 2016 (UTC)[reply]

(admission: I don't know this well, caveat lector) Another issue is temperature: cold dark matter, for example, is apparently considered problematic because it ought to accrete into more dwarf galaxy objects then it does. There are dodges suggested there like fuzzy cold dark matter that is too light to exist in any one place much. Dark matter in general is used to postulate huge fuzzy spherical haloes in which galaxies are suspended, so the premise is that, mostly, it doesn't stay put in spiral arms let alone stars, and so even "cold" dark matter is really hot by our standards, like 5% the speed of light hot. Of course, the characteristics of the type of dark matter needed to make galaxies spin like record albums may not predict the characteristics of some other unknown type of dark matter... Wnt (talk) 12:17, 9 December 2016 (UTC)[reply]

OK boss. I accept that dark is now really dark indeed. I hope that we can 'light' it up some day. Things like no collisions, less interactions, lack of electro magnetism but with gravity, different distributions are parts of twilight for better understanding in future.--G.Kiruthikan (talk) 16:08, 9 December 2016 (UTC)[reply]

Are humans ever harmed by highways?

Other animals always die on the road as roadkill. Squirrels may run across the street, and then - BAM - a car strikes them. Are primitive human populations ever harmed by highways too? Maybe an advanced human population builds fancy roads and drives cars, while containing a group of primitive humans in a park. The group of primitive humans can't go anywhere and can't follow the migratory animals. If they do, then they have a high chance of getting hit by a car on the road. 66.213.29.17 (talk) 17:33, 8 December 2016 (UTC)[reply]

I'm not sure about uncontacted peoples, but humans in modern urban USA are harmed by cars on highways all the time. In my current state of TX, we design things such that pedestrians have a very difficult and unsafe time. We killed two people with cars on Interstate 35 in Austin just this November [8] [9]. SemanticMantis (talk) 17:42, 8 December 2016 (UTC)[reply]

Have you heard of the Boulevard of Death? It averaged 2.5 dead pedestrians per mile per year in 1990. "The problem with Queens Boulevard is that everyone wants to get all the way across in one shot," said Mr. DePlasco. "We've been trying to teach people to be more patient, and cross half of it at a time.". It looks like a highway except usually 20+ intersections/mile and (in one part) 16 lanes, many elderly with canes, and not too far from Kowloon density (four subway tracks run under it or the neighborhood would be too dense to exist) Sagittarian Milky Way (talk) 21:20, 8 December 2016 (UTC)[reply]

Even the stupidest human is a lot smarter than the average squirrel. It's the difference between not knowing any better vs. not paying attention. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:51, 8 December 2016 (UTC)[reply]

It sounds like you're assuming that pedestrians are always at fault when they get killed by automobiles. That wold be a good example of victim blaming. Here in the USA, a pedestrian is killed about every two hours [10], and in my area, we are among the best in the nation at killing pedestrians with cars [11]. Maybe you're comfortable assuming that they were all "not paying attention", but I'm not. SemanticMantis (talk) 17:58, 8 December 2016 (UTC)[reply]

No, it could be the driver who wasn't paying attention. Or it could be both. ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:00, 8 December 2016 (UTC)[reply]

Fairly sure the OP was referring to cars driven by humans, not squirrels. Nil Einne (talk) 15:15, 9 December 2016 (UTC)[reply]

In my experience, there is considerable overlap between the smartest squirrels and the stupidest humans.[ Citation Need ed ] --Guy Macon (talk) 17:04, 9 December 2016 (UTC)[reply]

Could you specify what you mean by advanced and primitive humans? Those terms don't have any meaning in non-racist anthropology or sociology. I have to assume good faith that you're not a neo-Nazi, so I'm left perplexed by your terminology. Matt Deres (talk) 18:29, 8 December 2016 (UTC)[reply]

Primitive is still a common vernacular term. How is it derogatory?--Aspro (talk) 19:28, 8 December 2016 (UTC)[reply]

The difference between squirrels and "primitive humans" is that the humans, however "backward" their culture, very quickly learn from observation and from each other that highways are dangerous, just as children do in "advanced" cultures. Squirrels continue to scurry along roads in front of vehicles, apparently thinking that they can outrun them even when they observe squashed squirrel on the road. Dbfirs 21:33, 8 December 2016 (UTC)[reply]

I bet if some New York City pedestrians set spears and slew the oncoming beasts, they might make their roads as safe as roads in the jungle. :) (no, really, I don't know the statistics... feel like it could go either way though!) Wnt (talk) 22:22, 8 December 2016 (UTC)[reply]

You might want to look up road building in the Andaman Islands. -- zzuuzz ^(talk) 22:06, 8 December 2016 (UTC)[reply]

Comment There are several statements in this thread about the behaviour and cognition of squirrels, all of which totally unreferenced. This is a science reference desk - such statements should be supportable by RS. DrChrissy ^(talk) 22:39, 8 December 2016 (UTC)[reply]

Yes, apologies to all the red squirrels that I see squashed on the road. Perhaps they all deliberately committed suicide? Apologies to all readers for my WP:original research. Dbfirs 23:15, 8 December 2016 (UTC)[reply]

The premise is ludicrous that "an advanced human population builds fancy roads and drives cars, while containing a group of primitive humans in a park. The group of primitive humans can't go anywhere and can't follow the migratory animals. If they do, then they have a high chance of getting hit by a car on the road." No human is considered an animal. There are no "primitive humans". The question is nonsensical. Bus stop (talk) 23:26, 8 December 2016 (UTC)[reply]

The last time I looked at taxonomy, humans ARE considered to be animals. DrChrissy ^(talk) 23:39, 8 December 2016 (UTC)[reply]

We regard all humans differently than we regard all animals. There are no "primitive" humans. The word can be used figuratively only. Bus stop (talk) 23:46, 8 December 2016 (UTC)[reply]

Previously, you used the word "considered". I, and I suspect 99.99% of other biologists consider humans to be animals. Please note, I have not used the word "primitive". DrChrissy ^(talk) 23:55, 8 December 2016 (UTC)[reply]

Animals are forms of life. Humans are forms of life. Humans are animals. But humans are distinct from other forms of life and other animals. This could change. We can entertain ideas of forms of life elsewhere in the universe that we would have to regard as equal to ourselves in their humanness. But on the planet Earth we regard no other form of life as human except for humans. I know you didn't use the word primitive. And my response is not just based on the use of the word primitive. It is a word and it encapsulates my objection to the initial post. But the rest of the post implies a differentiation between one population and another: the highway builders on the one hand and those who are more primitive and follow migratory animals and might, in their particular stupidity, get hit by cars, on the other hand. This postulated scenario contradicts the actual relationship between humans and other forms of life on Earth. Bus stop (talk) 00:15, 9 December 2016 (UTC)[reply]

Thanks for this. I think we are in agreement that humans are animals. I will let others comment on other aspects of this thread. DrChrissy ^(talk) 00:46, 9 December 2016 (UTC)[reply]

Especially the ones with PhDs who dress fashionably and are connoisseurs of fine wine and especially the aficionados of current cultural entities and who have bank accounts containing enormous quantities of disposable income—they are really animals. Bus stop (talk) 01:42, 9 December 2016 (UTC)[reply]

The premise isn't that ludicrous. It could be a home for folks with Alzheimer disease, or a very good frat party. Wnt (talk) 12:21, 9 December 2016 (UTC)[reply]

Humans are harmed by highways (or roads as we Brits call them) in many ways other than being hit by cars. For example, living near a busy road exposes humans to pollution contributing to respiratory problems such as asthma. Living by a road can also be a source of noise pollution, which can in turn interfere with sleep and increase blood pressure. — Preceding unsigned comment added by 86.142.162.185 (talk) 13:03, 9 December 2016 (UTC)[reply]

Only the section heading asks "Are humans ever harmed by highways?" The body of the text posits a question predicated on the notion that primitive humans, contained in a park, can't follow migratory animals without crossing highways. This is ludicrous firstly because there are no primitive humans. Secondly no humans are contained in a park. The question posits that some humans are not human. Now, it might be that some humans are not regarded as human, but that is highly problematical and the entire scenario of the question is completely asinine. Bus stop (talk) 13:37, 9 December 2016 (UTC)[reply]

That is a somewhat charitable description of The Village (2004 film), which is one of M. Night Shyamalan's better efforts. Wnt (talk) 13:42, 9 December 2016 (UTC)[reply]

Both the driver and the pedestrian could be paying attention and the car could be at fault, as explained in this post:

In the news this week [12] a motorist died as he hit a parked lorry at 119 m.p.h. after his car's cruise control got stuck. In a call to the police he said

the brakes did not respond
he was afraid to apply the handbrake
the gear lever did not stay in neutral
the button to switch the engine on and off did not work

Turing test considerations

In Turing test are there any problems with asking simple questions like "What's your hair color" or "Which person do you find attractive and why?" and/or more complex ethical/moral or judgemental open-ended questions? For instance, "in a disaster would you save the child or the dog in distress first and why?" Is it assumed that the machine can give false answers like "My hair color is black" or refuse to answer ("I don't know", "I don't want to tell", etc.)? As a side note, our article is a bit ambiguous. According to it, Turing asked "Can machines think?", so presumably the point of the test is not to determine whether one is chatting with a machine or not, but to determine its ability to think on its own. Brandmeister^talk 17:52, 8 December 2016 (UTC)[reply]

Near as I can tell, that's not quite it - it's to gauge whether the entity you're conversing with is distinguishable from a human, or not. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:57, 8 December 2016 (UTC)[reply]

The Turing test is not a set of questions, or even a style of questioning. It's a means by which to assess sentience; the idea being that sentience (and in general, other issues related to the Hard problem of consciousness) is not something which can be assessed except by other sentient beings. Just as Justice Potter Stewart once said of obscenity "I know it when I see it", the test for sentience is "Can another sentient being tell the difference". If a machine can interact with humans and those humans can't tell they are talking to a machine, the machine can (for all intents and purposes) be described as sentient. Philosophically, the Turing test is of the school of behaviorism, which holds that the only thing you can study about something is its behavior. If it isn't observable, it isn't testable. The Turing test sets out to qualitatively assess if a machine behaves sentient. If it does so behave, then we must say that it is. Also, the person who assesses the Turing test is not the person interacting with the machine. The assessor is a third-party evaluator: If I read a text conversation between, say, Jane and John, and I know that one is a machine, can I reliably pick out the machine from just the text of the conversations. The conversation is supposed to be structured as natural as possible, and not merely be a script of questions.--Jayron 32 18:20, 8 December 2016 (UTC)[reply]

The Turing test can demonstrate that something appears to be sentient. But that does not logically lead to the conclusion that it actually is sentient. ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:30, 8 December 2016 (UTC)[reply]

See Behaviorism and more to the point Experimental analysis of behavior. If you can't measure it, it doesn't exist. If it behaves as sentient as you are, then it is. --Jayron 32 19:10, 8 December 2016 (UTC)[reply]

This is the kind of reasoning that ancient peoples used to conclude that natural phenomena are "alive". ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:16, 8 December 2016 (UTC)[reply]

What is your alternate method of proving a phenomenon is happening if it cannot be observed or measured? If something exists, it can be measured. If it cannot be measured, it does not exist. What is your proof of sentience? --Jayron 32 19:18, 8 December 2016 (UTC)[reply]

It's most likely the constant failure to rationalize a particular decision in a series of open-ended questions during conversation. If a machine repeatedly fails to offer either human or better-than-human solutions to moral and judgemental open-ended questions, then it's not sentient. If it does not, then it's sentient. Brandmeister^talk 19:41, 8 December 2016 (UTC)[reply]

Actually, the biggest problem right now is the AI-hard problem of natural language processing; which is mostly about deriving context clues from conversations based on assumed shared life experiences. Morality is still a set of rules, and machines can be made to learn the rules, or to develop their own morality from interactions with others (i.e. infer rules from observation, as most humans do). These issues are noted at the article I cited below. --Jayron 32 20:11, 8 December 2016 (UTC)[reply]

Is there any similar test that, like the Turing test, tries to assess being sentient, but that's based on a non-behaviorist framework? Many cognitive scientist are not behaviorists, and would like to test it through different means.Llaanngg (talk) 18:37, 8 December 2016 (UTC)[reply]

There are things like the Hutter Prize which is based around the notion of AI-completeness and Natural language understanding, the idea being that data compression is a reasonable analogue for artificial intelligence. --Jayron 32 19:17, 8 December 2016 (UTC)[reply]

I'm prone to apply the Turing test in unusual ways. Like, if you're in a room full of people who despise you but none of them says anything obviously hostile, they pass the Turing test for liking you, hence they like you. If someone reels off a line of pseudoscientific crap about his brilliant new perpetual motion machine and you can't see it's wrong, it passes the Turing test for physics, hence it's valid physics... :) Wnt (talk) 19:23, 8 December 2016 (UTC)[reply]

Yes, so if we are assessing sentience or are about "to gauge whether the entity you're conversing with is distinguishable from a human", then again what's wrong with asking open-ended questions that are germane to humans? Our article states that it's "a test... of a machine's ability to exhibit intelligent behaviour equivalent to, or indistinguishable from, that of a human". Since per article the evaluator "would judge natural language conversations", he/she might identify the machine answers as easily as the one who asks those open-ended moral or subjective human-centered questions. The evaluator may looks into machine's answers and figure out for himself/herself. Brandmeister^talk 19:23, 8 December 2016 (UTC)[reply]

You can ask anything and the computer is allowed to say anything. The way I interpret the test, you should try to determine whether or not you are talking to a normal, cooperative human. "Normal" for example means not insane or retarded, and "cooperative" for example means willing to give honest answers to questions humans wouldn't usually be unwilling to try to answer. For example, if you ask "Would you rather be sick or healthy?" then a human should probably be assumed to say healthy. If the answer is "Sick", "I don't know", "I don't want to tell", or something evasive like "That's an interesting question", "That's a silly question", "What do you think?", "Why do you want to know?" or "How about yourself?", then a computer will probably be judged to have failed the test, even though some humans would also give such responses. PrimeHunter (talk) 19:55, 8 December 2016 (UTC)[reply]

That's the kind of questions I was interested in. I thought that specifically human questions like the aforementioned "What's your hair color", "Which person do you find attractive and why?" and similar open-ended questions is a much simpler way to test the machine than complex scenario designed by Turing himself or others. Brandmeister^talk 22:24, 8 December 2016 (UTC)[reply]

What people perceive and what is real are not necessarily the same thing. I could argue that the little fortune-telling machine in that one episode of The Twilight Zone passes the Turing Test, because people are reacting to it as if it were a conscious being. They're thinking it is, doesn't make it so. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:49, 8 December 2016 (UTC)[reply]

You could argue it. You'd be wrong. But you could certainly make your mouth say those exact words. Saying words doesn't make them correct, you know. --Jayron 32 01:30, 9 December 2016 (UTC)[reply]

What's your basis for arguing against the fortune-telling machine passing the Turing Test? ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:04, 9 December 2016 (UTC)[reply]

Do you have a reliable source that shows the results of someone doing so? If you don't, there's a concept called the null hypothesis which basically says that unless you have actual positive results from an actual time someone did something, then it isn't valid to say a concept is confirmed. It's always the person proposing a statement like "a fortune telling machine would pass the Turing test" to provide the evidence that it is true. You cannot just make statements at random and then demand that the world prove you wrong... The burden of proof lies with the person who is making the positive assertion. --Jayron 32 09:51, 9 December 2016 (UTC)[reply]

Are you aware of anything that has actually passed the Turing Test? ←Baseball Bugs ^{What's up, Doc?} carrots→ 11:51, 9 December 2016 (UTC)[reply]

No, I am not aware of one that has. Turing test#Predictions notes when people have guessed a computer WOULD pass it, but they have to keep nudging their estimates upwards. --Jayron 32 13:34, 9 December 2016 (UTC)[reply]

Here are some Dilbert strips that reference the Turing Test idea.[29] ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:25, 9 December 2016 (UTC)[reply]

I encourage anybody interested in this topic to actually read Computing Machinery and Intelligence, the essay in which Turing proposed his test. It is widely available online (for example at http://loebner.net/Prizef/TuringArticle.html), and very well written. Looie496 (talk) 14:50, 9 December 2016 (UTC)[reply]

I should note that my responses above to Bugs's misunderstanding of the Turing test are not meant in no way to imply that I am endorsing those answers as reality. That is, in the sense that I believe that the Turing test would be able to prove that computers could think in the way that humans can think. I was merely presenting information that already exists about what the Turing Test is and what it is based on (that's why it is so frustrating to be argued with, as though I had invented it, or that I could un-invent it by merely being convinced strenuously by those who disagree with it). I have not agreed with the Turing test (and in saying that, I am also not DISAGREEING with it); indeed my state of mind on the matter is open and I'm not really looking to be "convinced" to believe anything about it one way or the other; convincing me it is bullshit is useless, because I don't believe it to not be bullshit (and in saying that, I also don't believe it to be bullshit. I don't believe anything about it at all). Indeed my belief about its validity is unimportant, I am merely serving as a conduit to explain how it works. In the interest of providing information about other perspectives on artificial intelligence (and in providing this information, I am also not endorsing it anymore than I am endorsing what I have already presented about the other side), one should also read up on John Searle's Chinese room argument, which is perhaps the best known, and best articulated, refutation of the behaviorist approach by the Turing Test. @Llaanngg: asked above about such non-behaviorist responses to the Turing test, and that's a good place to start research on it. --Jayron 32 15:21, 9 December 2016 (UTC)[reply]

The point in the Dilbert panels is to show a robot passing the Turing Test while the real humans fail it. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:11, 9 December 2016 (UTC)[reply]

Apollo machete

Why did the designers of the Apollo command module suppose that the astronauts might need a machete? I'm not aware of any jungles on the moon (or at their landing in the ocean). SpinningSpark 21:11, 8 December 2016 (UTC)[reply]

When you splash down back on Earth you might need to cut parachute cords and whatnot. 91.155.195.247 (talk) 21:28, 8 December 2016 (UTC)[reply]

They were going to the Moon which stays within +/-28 point something degrees declination (sky equivalent of latitude from equator). So that an emergency landing in an unplanned place might be in Earth's tropics is not far fetched. This may have been a consideration. Sagittarian Milky Way (talk) 21:40, 8 December 2016 (UTC)[reply]

According to every website I can find, these machetes were meant for jungle use, in case that's where the module landed. And the design allowed them to double as a prying tool if that was needed for whatever reason. However, I haven't been able to find any official documentation for why NASA commissioned these knives, so I'm not entirely sure where these sites got their information. The Smithsonian Institute apparently gives lectures on "space knives", but I haven't found a video or transcript available online. Someguy1221 (talk) 21:46, 8 December 2016 (UTC)[reply]

I'm not sure if it is good for prying. I read "Although the machete has yet to be needed on a mission, it has proved to be a very useful item during the training exercises. The blade is of high-quality stainless steel, but is brittle and will break if used for prying. A more desirable material for the blade should be considered for further development."[30] Bus stop (talk) 02:06, 9 December 2016 (UTC)[reply]

The claim is that the prying would be done with the ricasso, rather than inserting the point into something and then putting pressure on the handle. That should minimize the chance of breaking. But the geometry then would only make it possible to pry things by the corner... If they were already giving astronauts a 17 machete, presumably they also could have given them a proper prying tool if they thought it was necessary. Someguy1221 (talk) 02:51, 9 December 2016 (UTC)[reply]

Considering the Apollo astronauts were trained in jungle survival, it makes sense to give them tools for surviving in such an environment. WegianWarrior (talk) 21:50, 8 December 2016 (UTC)[reply]

Nothing to add except I found this picture of the full "Survival Kit #1" mentioned in the first link. Alansplodge (talk) 22:31, 8 December 2016 (UTC)[reply]

Bingo! "The survival kit is designed to provide a 48-hour postlanding (water or land) survival capability for three crewmen between 40 degrees North and South latitudes". From Apollo 11 Lunar Landing Mission Press Kit (page 135). Alansplodge (talk) 22:39, 8 December 2016 (UTC)[reply]

Slightly related, you might find TP-82 interesting. Vespine (talk) 23:27, 8 December 2016 (UTC)[reply]

So if it came to a fight, cosmonauts would beat astronauts! SpinningSpark 00:17, 9 December 2016 (UTC)[reply]

And they could use the knives if they got into a fight with aliens on the Moon. Bubba73 ^{You talkin' to me?} 01:41, 9 December 2016 (UTC)[reply]

They were for survival if they had to make an emergency landing away from the landing zones. See this. Bubba73 ^{You talkin' to me?} 23:36, 8 December 2016 (UTC)[reply]

Today, the main webpage at NASA.gov published a set of historical images of John Glenn... usually, like most pilots, he looked pretty sharp with those aviator sunglasses and closely cut hair - but there were also a few photos that you might not have seen before, showing him and his fellow astronauts looking pretty scruffy:

The Original Mercury Seven During Survival Training, at Stead Air Force Base (now Reno Stead Airport, home of the Air Races). "Portions of their clothing have been fashioned from parachute material, and all have grown beards from their time in the wilderness." We've all been there!
Survival Training: "Some of NASA's sixteen astronauts participate in tropic survival training from June 3, through June 6, 1963, at Albrook Air Force Base, Canal Zone"

One thing to remember is that spaceships (and jet airplanes, for that matter) fly very fast. In a slow airplane, you can get miles beyond the edge of human civilization in just a few seconds. If you have to bail, you may bail into a place where there are no roads, no lights, no help. In a jet, you might be tens of miles from help after flying for just a few seconds.

In a spaceship, you can easily end up a few hundred miles off course. You might end up in a different time and climate zone than your rescuers. NASA prepared astronauts to survive.

Here's NASA Tech Note TN D-6737: Apollo Experience Report - Crew Provisions and Equipment Subsystem (1972). Page 30 describes the infamous machete. Although the machete has yet to be needed on a mission, it has proved to be a very useful item during the training exercises.

If you should ever find yourself a few miles from help, you might wish you had a machete among your equipment. It's a generally useful tool. At the very least, you can use it to shave.

When you travel in space, you've gotta be prepared to land in sand or snow, oceans or deserts or forests or mountains or foreign lands... Earth is a strange and mysterious place!

Nimur (talk) 23:46, 8 December 2016 (UTC)[reply]

Scott Carpenter in Mercury-Atlas 7 overshot the landing site by 250 miles. Bubba73 ^{You talkin' to me?} 00:14, 9 December 2016 (UTC)[reply]

Considering the Earth's circumference is 25,000 miles, and he's basically aiming an unnavigable hunk of metal at it from a few hundred miles above the earth and coming within about 1% of his target. That's pretty freaking good, if you ask me... --Jayron 32 01:26, 9 December 2016 (UTC)[reply]

Machete in Space! --Guy Macon (talk) 08:10, 9 December 2016 (UTC)[reply]

I have added a brief section to Survival kit#Spacecraft kits using refs provided above. Alansplodge (talk) 12:05, 10 December 2016 (UTC)[reply]