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May 12

Percentage of Muslims that self-identify as British-first or muslim first

Out of Muslims living in Great Britain,what percentage of them identify as Muslim-first, and what percentage identify as British-first? — Preceding unsigned comment added by 70.180.208.48 (talk) 03:00, 12 May 2016 (UTC)

In other words, how many people identify as "Britons who are Muslim", and how many are "Muslims who are British" — is that what you're asking? Nyttend (talk) 03:50, 12 May 2016 (UTC)

Yes — Preceding unsigned comment added by 70.180.208.48 (talk) 04:08, 12 May 2016 (UTC)

In a recent survey 17% said their Muslim identity was more important than their British identity, 6% said their British identity was more important than their Muslim identity, and 76% said they were both equally important to them. http://survation.com/new-polling-of-british-muslims/ 81.132.106.10 (talk) 08:21, 12 May 2016 (UTC)

If you ask a silly question you usually get a silly answer. The value of such an answer in the real world is 0. The Quixotic Potato (talk) 16:36, 12 May 2016 (UTC)

This isn't a silly question, but it's much more humanities than science. It's addressing an aspect of cultural assimilation that's rather similar to the cricket test, although it addresses different aspects of the same basic issue. Nyttend (talk) 02:46, 13 May 2016 (UTC)

It is a silly question, and the answer is meaningless. Take the same question, but replace Muslims with (for example) Jews or Jehovah Witnesses or whatever and replace Great Britain with another random country, for example Liechtenstein. Do you understand why the question is silly now? Feel free to disagree though! The Quixotic Potato (talk) 02:57, 13 May 2016 (UTC)

It's not exactly silly, it's more like hinting at the notion that Muslims are disloyal, and the question is possibly driven by the recent election of a Muslim as mayor of London. It's basically Trumpism. ←Baseball Bugs ^{What's up, Doc?} carrots→ 07:10, 13 May 2016 (UTC)

True, I used "silly" as a euphemism, but I am far too kind. I think that people who question the loyalty of the Jewish people in Liechtenstein are antisemitic idiots. I didn't know "Trumpism" was a new euphemism for this kind of hate, but it is quite fitting. My userpage contains a special message to Donald Trump. The Quixotic Potato (talk) 11:28, 13 May 2016 (UTC)

@The Quixotic Potato: The question may be offensive to some, but it isn't silly or idiotic. After all, there has to be somebody who would far rather see Tel Aviv or Cairo prosper than London. Some people actually have conflicting allegiances (and probably more often, none at all). It is difficult to answer, for obvious reasons, but it should not be altogether unanswerable. I think rejecting legitimate thought like this out of hand is not a way to suppress prejudice, but is more likely to inflame it. If you want to stop prejudice, then you need to marshal and drill an army of counter-arguments, such as the number of Muslims who have died in military service or who have risked their lives in a civilian role. If you feel it is beneath you to argue your case, do not be surprised to lose. Wnt (talk) 22:25, 13 May 2016 (UTC)

@Wnt: For all religions I know about I am an atheist/nonbeliever, and in general I am a theological noncognivist and an ignost (no, that is not a typo). I am incredibly lucky because I was born in one of the least shitty places in the world (Amsterdam, the Netherlands). I am Dutch by default, not by choice. My great-grandfather wore klompen and slept in a bedstee. I don't feel a special connection to people who happen to be from roughly the same geographical area (my country is only 200 by 300 kilometers by the way). Being an Amsterdammer and a netizen has had a far greater influence on me than being Dutch. See [1]. You seem to be American; I have never visited your country but I am under the impression that in America nationalism is far more common than it is here. In 2015 a report was published that states that approximately 67.8% of the population in my country has no religious affiliation; the population of the USA is about 70% Christian. Are you religious? Of course I don't feel a special connection to other atheists; the best thing about being an atheist is that we are not members of a club. Do you agree with me that people who question the loyalty of Jewish people in Liechtenstein are antisemitic idiots? Would you have written the same thing if the question was about Jewish people in Liechtenstein (or Jehovahs Witnesses in Finland, or Buddhists in Greece)? The question is silly (I am using that word euphemistically), and the answer is meaningless. Feel free to disagree. Lose what? A hypothetical discussion that hadn't even started yet? Who decides? Is there a referee? Who cares? We are building an encyclopedia, no one is keeping track of the amount of times I "win" or "lose" a discussion afaik. Does "winning a discussion" mean that you actually have to convince someone? I have that famous Oscar Wilde quote on my userpage: "it is well to remember from time to time that nothing that is worth knowing can be taught". If you do not understand why the question is silly then I don't think I can help you with that. I wish I was as hopeful and optimistic as you are; you seem to believe that rational arguments are effective weapons against prejudice and stupidity. Maybe I am old and bitter, but in my personal experience the reality is far more complicated. I believe that if you want to stop prejudice you'll need to wipe out the human race (and quite a few animal species). I don't really think many things are beneath me, and arguing my case certainly isn't, but there are many other reasons why I am not really interested in explaining something like that in detail over the internet to random people I don't know. The Quixotic Potato (talk) 23:20, 13 May 2016 (UTC)

@The Quixotic Potato: I was actually talking about your hypothetical Liehtenstein case when I mentioned Tel Aviv above. There are actually times when this question can become relatively relevant, though not so much by the Jews' doing. For example, I was stunned to learn last year that the British Home Secretary can, pretty much on his own interpretation of a rather cryptic phrase, revoke citizenship of people who might reasonably be expected to be able to obtain citizenship elsewhere, which I assume includes Jews, and also includes residents of many Islamic states. [2] Now in a situation like that, where a person cannot be confident he will always have the right to be a British citizen and could be deported to some other country, he might be expected to start thinking about whether he will be safe and accepted in that country rather than Britain. Where racism is concerned, the people here discussing didn't start that fire - it's the bureaucrats with their policies and their forms and their databases and social programs who run that show.

As for optimism, well, there are a lot of different issues in the world, but I remember in the 1980s it seemed like the U.S. having a black president was a pure pipe dream; but even more profound is the difference in the gay rights movement, which is usually considered to have officially started in 1969 with the Stonewall riot. In the 1980s, sodomy was still formally illegal in much of the U.S. Followers of Lyndon LaRouche were all over the country advocating for a round-up and quarantine of people who had or might catch HIV, an epidemic very few people in government seemed to view as a bad thing. Not one person in ten knew that there were other species that could be homosexual. But people argued and rallied and made their point, and the situation changed. So with things like that, I would not dismiss the usefulness of explanations and discussions. Wnt (talk) 08:05, 14 May 2016 (UTC)

@Wnt: Vaduz is the capital of Liechtenstein. London is the capital of both England and the UK. AFAIK I didn't dismiss the usefulness of explanations and discussions. Did someone "lose" or "win" this discussion? The Quixotic Potato (talk) 08:14, 14 May 2016 (UTC)

I lost a few minutes reading it and judging it a tie. Ten points to everyone. InedibleHulk (talk) 08:33, May 14, 2016 (UTC)

By "lose" I did not mean you vs. me, but you vs. racism, as I got the impression you wanted to oppose it. Wnt (talk) 09:16, 14 May 2016 (UTC)

I don't think I understand what you mean. How can a single potato defeat racism? Racism will still be here after I am gone, does that mean that I lose and racism wins? I do not have nuclear weapons (very few potatoes do). The Quixotic Potato (talk) 09:56, 14 May 2016 (UTC)

Hillary Clinton will acquire nuclear weapons next year, by appearing less racist next to someone else. And then every man, woman and child on the planet can equally identify as "terminated". Till then, the stalemate drags on. InedibleHulk (talk) 11:47, May 14, 2016 (UTC)

Doesn't pass objectivity test. Most religious people I know identify with their religion first, regardless. Even the most patriotic, such as voluntary soldiers willing to die for their country, still have "God, Country, Family" as a fundamental understanding of precedence. It's the basis by which conscientious objectors have their religious beliefs respected (i.e. Quakers in the U.S.). I'd be surprised if people choose one over the other as an identity but religious beliefs can trump duty requests to country or family. --DHeyward (talk) 02:23, 14 May 2016 (UTC)

I think identity and loyalty are being incorrectly conflated here. It's hard to imagine how anyone who believes in God could disagree with the proposition that loyalty to God is more important than loyalty to country. That's a different question from whether you identify more with your compatriots or your co-religionists. (As an individualist, I think all this "identification" stuff is way overrated anyway. And no, I don't "identify as an individualist"; I just am one.) --Trovatore (talk) 02:36, 14 May 2016 (UTC)

posting of banned user removed. Fut.Perf. ☼ 08:15, 16 May 2016 (UTC)

Thanks for proving my point. Being a misanthropist is not the same thing as being anti-social. In my country there are non-religious burial services btw. You should read my userpage, I love real Christians like Wade Watts and I dislike hypocristians like the Westboro Batshit Church and yourself. Please judge me, and cast the first stone. I suggest you go read the bible, and then apologize. The Quixotic Potato (talk) 09:28, 15 May 2016 (UTC) p.s. It is possible that you are a troll who is trying to make Christians look bad, if so then you have achieved your goal. If not, then I have to inform you that you just made Jesus facepalm. I am an nonbeliever in religions without a god or gods, and an atheist for all theistic religions. I probably wouldn't even mind being described as an anti-theist. @Gerda Arendt: The IP 151.226.217.27 does not understand your religion. Maybe you can explain it to him.

posting of banned user removed. Fut.Perf. ☼ 08:15, 16 May 2016 (UTC)

You are a hypocristian, it is a portmanteau of hypocrite and Christian. The Westboro Batshit Church is a bunch of people who do not understand the Bible, just like you. There are many nontheistic religions. No, you do not understand Gerda's religion, because she is a Christian. The Quixotic Potato (talk) 12:50, 15 May 2016 (UTC)

Sort of a pity that we have an article on nontheistic religions, but none on nonreligious theism. It certainly exists; I'd go so far as to say that it's a pretty popular position, at least if you take it broadly to include people who follow religious observance for social reasons, and also believe in God, but don't think that the first has much to do with the second. --Trovatore (talk) 20:07, 15 May 2016 (UTC)

[un-indent] This is a perfectly legitimate question, but it belongs on the Humanities (or Miscellaneous) reference desk, not here! 2601:646:8E01:515D:F88D:DE34:7772:8E5B (talk) 01:32, 17 May 2016 (UTC)

For which person is more easier to lift his hands?

For which person is more easier to lift his hands, to someone thin or for someone muscular? I think that for the thin it's more easier because for the muscular guy he needs to carry heavy muscles = more weight. But I'm not sure about that. 93.126.95.68 (talk) 09:32, 12 May 2016 (UTC)

But muscles are the part of the body that does the lifting. The extra weight of the muscles is cancelled out by how much more the muscles could carry. Otherwise, no one in history would have ever tried to develop their muscles in any way, shape, or form. Ian.thomson (talk) 09:36, 12 May 2016 (UTC)

The muscles that lift the hands are well away from them and it is mainly tendons that contribute to the weight. This is even more so for your fingers, most of the muscles for them are in your forearm, see arm abd Muscles of the hand. Dmcq (talk) 12:11, 12 May 2016 (UTC)

probably not an answerable question as stated...what is meant by "easy"? how much total energy is required by the movement? how the movement subjectively feels to the individual? etc etc.68.48.241.158 (talk) 14:59, 12 May 2016 (UTC)

Who's in better shape, the 180lb man or the 300lb man? Now put 120lbs of stuff on the 180lb man so they weigh the same. I'm betting the 300lb man being accustomed to the weight does better than the guy with weights added. --DHeyward (talk) 02:27, 14 May 2016 (UTC)

Exercise: Repetition vs. weight lifted.

I have decided to move to a more structured exercise program. Right now I bike, sprint or jog, swim or lift weights, etc., based on what I am in the mood for.

So I looked at a few exercise websites, and I am now totally confused about repetition vs. weight lifted. So let's assume to keep the numbers simple that I can lift 100 Lbs -- once. If I try a second time I can't make it. Pretty much everyone agrees that maximum weight and one repetition is a bad exercise program. So I switch to 1 pound, and find that I can do many, many repetitions. Still not good. My heart rate and breathing don't increase much and I quit because I get bored.

I have also noticed that top sprinters or marathon runners and top distance runners or power lifters have different kinds of muscle development. I am kind of looking for the ability to lift a heavy weight, because that fits the kind of work I tend to do; "grab the longest wrench and we have try to unstick that 2-inch OD bolt". But I don't want to totally neglect my heart and lungs either.

So let's say I reduce the weight until I can do 10 repetitions but not 11. Compare that to being able to 30 but not 31 with a lighter weight. Which will be best number of repetitions for building muscle mass? Which will be best for cardiovascular fitness? Weight loss?

Surely someone has done some scientific research on this question. Alas, doing a web search on it is like drinking out of a fire hose. --Guy Macon (talk) 10:02, 12 May 2016 (UTC)

There is training for strength, power, endurance and hypertrophy. All require a different combination of sets and reps. It is not only weight vs. number of repetition. There are other variables you have to keep an eye on: speed, sessions per week, rest between sessions, reaching muscle failure (or not). Take a look at this table: [3].Llaanngg (talk) 12:16, 12 May 2016 (UTC)

Interesting! In the chart, what is the difference between strength and power? --Guy Macon (talk) 12:22, 12 May 2016 (UTC)

Strength: how much weight your muscles can move. (important for weight lifters)

Power: how quickly you move a weight. (important for martial arts, javelin/discus/hammer throwing).

Notice the difference in appearance between a weight-lifter and a martial arts practitioner Llaanngg (talk) 12:29, 12 May 2016 (UTC)

So any idea where that table came from, or a ref that might explain this distinction? I mean thanks for this good info but it doesn't really help us dig in to any further refs. My suggestion for OP is to get a nice medicine ball and read up on various techniques - Many people think they are fun and he might find the less boring than other exercises too :) Here is a general list [4] of techniques that also contains some good looking book refs. Here [5] is a video specifically geared toward developing punching power by using a ball, and here's one for endurance [6]. SemanticMantis (talk) 22:21, 12 May 2016 (UTC)

I think the question is a good one and I'm surprised there is not more on it. About the boring business - I must admit I just don't understand why people want to bore themselves stiff trying to get bulging muscles. There's lots of alternatives which are much more social, my main exercise is dancing which is fun and has a mental component which I think is good. Dmcq (talk) 22:57, 12 May 2016 (UTC)

Here's a small selection of somewhat relevant and freely accessible scientific studies on the topic: [7] [8] [9] SemanticMantis (talk) 23:06, 12 May 2016 (UTC)

I got into gym work and weight lifting for a while and one thing I noticed is that there are almost as many answers to this question as there are people who are training at gyms. And MOST of it is just based on personal opinion and anecdote. The general rule of thumb seems to be: the lower your "reps to fail" the more you are working on bulk and strength, the higher your reps to fail the more you are working your lean muscle and stamina. Low reps are in the range of 4-8 high reps is 10-14. If you are starting out, you can't go wrong with 3 sets of 8 reps for a while, learn a bit about which groups of muscles you should train together and which you should train separate. Once you start seeing improvement in your strength and you are increasing the weights you can lift, make an appointment with a personal trainer and have them create a training program specifically for what you want to achieve. With SO many pro atheletes, weight lifters, trainers etc, you'd think a question like Training to failure would be figured out by now, it's either better or not, but clearly so much of this topic is so complicated that even a seemingly easy question like this has a lot of room for experts to disagree. Vespine (talk) 23:09, 12 May 2016 (UTC)

If you're not looking for something too specific you're much more likely to stick to exercises you enjoy doing.Bastardsoap (talk) 16:14, 14 May 2016 (UTC)

Thread gauge T and Z for Go and No Go

"Normal" thread gauge says "Go" on one end and "No Go" on the other end, simple enough. But this set[10] I brought says "T" on one and "Z" on the other. Which letter correspond to "Go"?

And where did the "T" and "Z" come from? I'm guessing German?

I tried googling "thread gauge t z" but queries with single letters in it are hopeless.Johnson&Johnson&Son (talk) 12:05, 12 May 2016 (UTC)

If you believe this http://www.ebay.com/itm/Metric-Thread-Ring-Gage-Gauge-Set-M12-x-1-5mm-6G-T-Z-/171427721156 T = go, Z = no go --TrogWoolley (talk) 13:01, 12 May 2016 (UTC)

Other sellers say the same thing [11] [12] [13]. BTW, while searching for single letters is often not productive it's not always the case and I wouldn't say it's the case here as these results were found from searching. I'm not really sure whether you meant searching for (without the single quotes) 'thread gauge t z' or '"thread gauge t z"' (i.e. including the double quotes). If you meant the later, it's not surprising that the results weren't useful. If you meant the former, the obvious problem is that many of the results either say 'tz' or don't even have the tz. In fact some of them aren't even finding 'thread gauge'. So the next logical search attempt may be 'thread gauge "t" "z"' or perhaps '"thread gauge" "t" "z"'. Both of these will probably find at least one of these results (either directly or indirectly) or similar within the first 10-20 results. Since go/no-go is believed to be the standard terminology the next obvious search is something like 'thread gauge "t" "z" go no go' or '"thread gauge" "t" "z" go no go' which doesn't actually seem to find anything much more useful although may find one of the above results in number one place (ironically not one using the go/no go terminology itself but coming from elsewhere) and perhaps a few more results earlier on depending on precisely what you're comparing with. Unfortunately neither seems to find where the symbology originates. Nil Einne (talk) 14:46, 12 May 2016 (UTC)

For those wondering what this thing is for, we have a Go/no go gauge article. If T/Z is a standard nomenclature, please update it. DMacks (talk) 16:47, 12 May 2016 (UTC)

Have updated article. For the non-metricated, is it clear enough to make sense? --Aspro (talk) 18:31, 13 May 2016 (UTC)

Thanks! I wordsmithed it a bit to clarify (I think:). But I do not have access the the full actual standard, so I am not sure if I am clarifying it correctly vs taking it in an incorrect direction. @Aspro: please check and let me know. DMacks (talk) 19:47, 13 May 2016 (UTC)

But following up, what is the etymology of T and Z?    → Michael J Ⓣ Ⓒ Ⓜ 23:45, 14 May 2016 (UTC)

Orbital axes

I know that every planet's orbit has a different eccentricity and inclination. What I wonder is, do the semi-major axes of the various orbits point in the same direction? Perhaps a better way of asking is, do the non-solar foci have any correlation to each other?    → Michael J Ⓣ Ⓒ Ⓜ 16:20, 12 May 2016 (UTC)

The orientation of the semi-major axis is not fixed but undergoes apsidal precession over many thousands of years (110,000 years for Earth). Since the various planets evolve at different rates, I assume their orientation at any given time relative to each other is mostly random. Dragons flight (talk) 16:33, 12 May 2016 (UTC)

While reading a magazine or similar article recently about the possible Planet Nine, I happened to notice that all (or possibly all bar one) of the planets' semi-major axes are confined within about (I think) 135° [subject to further checking] and wondered whether this might be more than chance. {The poster formerly known as 87.81.230.195} 185.74.232.130 (talk) 18:07, 12 May 2016 (UTC)

A range of 135 degrees over 8 planets is hardly how I would define "confined", considering that 180 degrees would be the maximum value for variance. --Jayron32 18:16, 12 May 2016 (UTC)

How is the orientation measured? By angle ±° from that of Earth?    → Michael J Ⓣ Ⓒ Ⓜ 18:32, 12 May 2016 (UTC)

I'm assuming it's 135 degrees from the furthest difference in axis: 90 degrees would mean the semi-major and semi-minor axes line up, and 180 degrees would mean that you're lined up again on semi-major axes. If we had them all within a small number of degrees, that would be "confined". 135 degrees seems like a fairly wide range of differences. --Jayron32 18:40, 12 May 2016 (UTC)

While it is true that 180° difference means that they are lined up again on the semi-major axis, it does not mean that that is the same as 0° difference—actually, viewed from above with one focus to the left and the other to the right, the foci of one planet's orbit are the Sun and something to its left, and the foci of the other planet's orbit are the Sun and something to its right. They go off in opposite directions, not sharing their second foci. So viewing these as extreme opposites, a range of 135° Is only half as great (i.e., compared to 360° rather than 180°). Still a substantial variation, though. Loraof (talk) 19:52, 12 May 2016 (UTC)

Actually, the correlated trans-Neptunian objects' orbits depicted at Planet Nine#Planet Nine hypothesis look like they range over about 135°. Apparently that is considered to be highly correlated enough to give rise to the hypothesis. Loraof (talk) 20:21, 12 May 2016 (UTC)

To add a little more clarity, I was indeed taking the axes to be directional from perihelion to aphelion, so the full possible range would be 360° {The poster formerly known as 87.81.230.195} 2.122.0.142 (talk) 01:19, 13 May 2016 (UTC)

I've heard that the planets' longitudes of perihelia get pulled back into a wide range by Jupiter's gravity when they stray too far. Sagittarian Milky Way (talk) 20:31, 12 May 2016 (UTC)

Icarus again

What arm flipper type would need the least antigravity for an average young man to fly? Purest flight: a stationary start without needing wind, thermals, running, jumping, updrafts, denser air, rotors, machines, energy storage, lifting gases, genetic engineering, doping, magnets, high altitude, space travel, oxygen (more than usual), multiple guys tied together, shock waves, moving the ground..

Is tapered better? Square tip? Low aspect ratio or high? Longer than arm or no? Aluminum wing for the poor and carbon fiber for the rich or something else? Sports racket shaped? (how big a handle and head?) Sagittarian Milky Way (talk) 20:05, 12 May 2016 (UTC)

Aerospace engineering is not easy. Even the experts seem to hang around wind tunnels and stare at models under polarized light to try to figure out the best scheme. And I don't know anything about it, which makes this tough for me to answer. :) But I'm thinking we might separate it into some sub-questions:

How light and tough can a material be? If a wing held up by one arm is (for example) 10x2 meters, how much does it have to weigh to be able to support itself and rider? I have no idea if there is a way to set a theoretical limit to that.

How low can the air resistance be on the upstroke, assuming the cleverest engineering? I have no idea if there is a way to set a theoretical limit to that.

How high can the air resistance be on the downstroke, assuming the best possible engineering to manipulate vortices and turbulence? I have no idea if there is a way to set a theoretical limit to that.

At this point I should vacate the floor in favor of the experts I hope to have nettled. Wnt (talk) 21:33, 12 May 2016 (UTC)

If you're seeking a scientific answer, it's pretty clear that there is no possible way to build a human-powered flight system that depends on flapping your arms, nor by using your own muscles to flap any contraption you can conceivably strap to your arms. The topic has been researched extensively. Start at human-powered aircraft. The most successful human-powered designs have been glider-like aircraft with propellers powered by the aviator's leg-muscles, using a bicycle-gear-like mechanism.

If you're using humans to power the aircraft, you wouldn't really want to use their arm muscles - the legs of a human can deliver more power, and power is what you need most.

Take a look at a small fixed-wing airplane propeller's airfoil: it's not actually very large at all, but it is attached to a powerful engine - typically an internal combustion engine. For example, my copy of the POH says that the Cessna 172 has a 75-inch diameter McCauley propeller. Accounting for the spinner dome and the prop root, that means that the entire 2550 pound aircraft is being pulled through the air by an airfoil whose wings are less than three feet long. The real magic technology that makes flight possible - at least, for heavy objects like humans - is power. With enough power, you can go flying even if you've got very short, stubby, drag-inducing wings. In fact, some people build them that way on purpose, because they're a lot of fun.

(I'm sure some glider pilots will have some different opinions... but our OP has specifically asked to exclude wind and thermals)...

As far as building materials, well... the original Bellanca Citabria was built with (mostly) wooden wings, but you can get about an extra hundred pounds of useful load if you fly out to the American Champion factory and have them perform a legal wing conversion to use an Aluminum Spar; and there are some who swear that the Carbon Cub is three hundred pounds lighter than the standard Super Cub...

Nimur (talk) 01:21, 13 May 2016 (UTC)

Without demurring from what you say, Nimur, you're ignoring SMW's stipulation of antigravity. If, for example, one was entirely supported in the air by 1 gee's-worth of antigravity (where did I put my cavorite belt?), one could obviously propel ones self to a degree with arm-operated 'wings', just as one can swim in the sea. Similar considerations would apply if one were in, say, air at 1 atmosphere of pressure in a lower or zero gravity environment. I bet it'd be bloody tiring, though. {The poster formerly known as 87.81.230.195} 2.122.0.142 (talk) 01:31, 13 May 2016 (UTC)

Right, human flight by flapping wings is essentially impossible on regular Earth with regular gravity, but with antigravity or even some level of lower gravity it should get much easier. In addition to lift and such, there's also the control system to think about. Wings on arms are unwieldy. OP may enjoy For_the_Birds_(short_story), which contains Asimov's solution to the problem. SemanticMantis (talk) 14:09, 13 May 2016 (UTC)

Actual number of turns

In the case of, say a step-down transformer, we know that the ratio of turns determine the ratio of ac voltage we get, respective to the input of ac voltage. Supposing that we have 100 turns at secondary coil while there are 5000 at the primary one, we get 4.4 v ac for 220 v ac. Now if we change number of turns from 100 to 1000 at secondary and to 50000 from the earlier 5000 at the primary (we may have to increase overall transformer size, of course),but we still will get 4.4 for 220, since turn-ratio is same. But it seems sure that some other overall improvement must have come in performance. What would precisely that be ? And why ? 124.253.246.178 (talk) 23:32, 12 May 2016 (UTC)

I think it might be efficiency: the larger the number of turns on the coil, the greater the flux linkage and therefore the greater the induced emf. [14]. --Tagishsimon (talk) 23:46, 12 May 2016 (UTC)

But the induced e.m.f. depends on the turns ratio which is stated to be unchanged.. The transformer with the greater number of turns has higher mutual inductance and can therefore be used at lower ac frequencies. Core saturation will however occur at a lower primary current, which limits the maximum power handling. If increasing the number of turns was achieved by using thinner wire, the efficiency loss due to Joule heating increases. See the article Transformer. AllBestFaith (talk) 00:04, 13 May 2016 (UTC)

Just as a curious factoid, a tesla coil can have thousands of turns in the secondary and as few as 6 in the primary! (maybe even fewer, but I know 6 for sure.) Vespine (talk) 04:56, 13 May 2016 (UTC)

And the other way 'round (hundreds or thousands in the primary, vs as few as one (!) in secondary) is a common college physics demo. DMacks (talk) 05:21, 13 May 2016 (UTC)

By increasing ten-fold the number of turns on primary and secondary, you will indeed get the same voltage as with the former transformer under no-load conditions. The problem comes when you connect a load that draws current. Let's assume that in the former transformer, the core size and wire size were adequate for the current drawn. Increasing the number of turns ten-fold implies a much bigger core to accommodate them. That's fair enough. But the Ohmic losses in the windings will now be ten-fold too, so in order to reduce these so that the transformer puts out the same voltage as before under load, wire with greater cross-sectional area must be used, again increasing the core size. I don't see any advantage. All I see is the negative impact of a heavier, larger, and more expensive transformer that is wasteful of natural minerals such as copper and iron. Akld guy (talk) 06:50, 13 May 2016 (UTC)

Do you mean that savings in world resources of copper and iron are to be had just by reducing ten-fold the number of turns on primary and secondary of transformers? AllBestFaith (talk) 13:31, 13 May 2016 (UTC)

@AllBestFaith: No, because there's a minimum core size for any transferred amount of power. The cross-sectional area of the core in square inches is the square root of V x A divided by 5.58, where V x A is the voltamps output Radiotron Designer's Handbook, p.235. So, assuming that the core size was correct initially, it cannot be made smaller. That also means that the number of turns in the primary winding cannot be reduced either, since the flux density would fall, severely reducing the output voltage under load. Akld guy (talk) 01:21, 14 May 2016 (UTC)

No, a minimum core size for a power transformer in Eurasia using 50 Hz can be reduced slightly (hardly significant in commerce) for use in the Americas at 60 Hz, be reduced markedly for an aeronautic 400 Hz power system, and be reduced much more (with a change of material) in a SMPS. The figure you quote is an empirical guide that, to guess from the source, is just for 50/60 Hz transformer cores. AllBestFaith (talk) 15:14, 14 May 2016 (UTC)

The comparison was one transformer configuration versus another. Nobody said anything about forcing a change to the frequency supplied by the electricity network so as to make the second transformer work better. Akld guy (talk) 21:18, 14 May 2016 (UTC)

May 13

Does a photon have any chance of crossing a metal plate?

If a metal plate is opaque (say, it's 5 mm thick), could a photon still have a tiny probability of crossing through it? --Llaanngg (talk) 00:25, 13 May 2016 (UTC)

Yes in theory. You will have to qualify what kinds of photons you are talking about. For gold you can make it thin and transparent, see Gold#Characteristics. For light, although there may be a tiny tiny tiny chance, perhaps 1:10⁻²⁰⁰⁰, the practical answer is no. For gamma rays the chance of penetration is high. But it depends on how much guarantee you need there will no photons. There may be a chance of corrosion, or damage due to people drilling holes in it, or perhaps the photon can get around the edge of your metal plate, that is diffraction. For radio wave photons diffraction becomes much easier. Graeme Bartlett (talk) 00:50, 13 May 2016 (UTC)

Radiation_protection#Electromagnetic_radiation states "X-ray and gamma radiation are best absorbed by atoms with heavy nuclei; the heavier the nucleus, the better the absorption. In some special applications, depleted uranium or thorium[7] are used, but lead is much more common; several centimeters are often required." Several centimeters is greater than 5 mm. --Jayron32 01:06, 13 May 2016 (UTC)

At sufficiently low frequencies (less than 100Hz say), there is a fair chance of a photon getting through without being absorbed - see skin depth. However, even at very low frequencies, most photons will be reflected rather than absorbed or transmitted to the other side, and only about 1 in 10⁸ 1 in 10¹⁶ will get through. --catslash (talk) 14:37, 13 May 2016 (UTC)

Well, the OP never specified which energy photon. Really, the difference we're talking about here can be the difference between firing a bullet from a gun versus lightly tossing one underhand. Exactly what the photon would penetrate would depend entirely on how much energy it has. --Jayron32 14:44, 13 May 2016 (UTC)

• Yes. They aren't stopped instantly, their intensity falls off exponentially with distance in. The proportions of this curve depend on materials behaviour and substantially on the photon energy. So for visible light and higher frequencies there's a "thin film" distance where a metal foil (or more usually a layer deposited on something else) can still allow an appreciable fraction through. These thin films are quite important to all manner of devices. Andy Dingley (talk) 14:49, 13 May 2016 (UTC)

Virtual photons may have a much better chance of getting though even thick copper. This may be why, NASA are getting promising results from their absolutely-impossible -to-believe RF resonant cavity thruster experiments.--Aspro (talk) 19:01, 13 May 2016 (UTC)

I'm not sure I would call it "promising." More likely they are looking for normal explanations to explain margin of error. --DHeyward (talk) 00:45, 14 May 2016 (UTC)

• Photons can also tunnel through metals via QM [15]. Spin Hall Effect article touches on it with few sources, though. I seem to recall a very precise gyroscope being built using this but can't find it. :( --DHeyward (talk) 00:45, 14 May 2016 (UTC)

What is the reason that the fox was considered always as the cleverest or smartest among the other mammals?

93.126.95.68 (talk) 03:41, 13 May 2016 (UTC)

Um, was it? Can't really answer this question without proof of the premise... --OuroborosCobra (talk) 03:46, 13 May 2016 (UTC)

Well, in folklore, sure, "as cunning as a fox". But this is barely a "science" question, maybe more humanities? Vespine (talk) 04:45, 13 May 2016 (UTC)

Anecdotally, i live in an area where there are wild foxes, I've seen them in my own back yard. They are elusive and they are harder to trap than a lot of other animals. It's not easy to lure them with a simple bait trap, it takes more effort to set up a trap that will catch a fox. The main reason might be because they are also very good at getting into chicken hutches, they are much stronger than a cat and about as smart as a dog making them a formidable predator. Vespine (talk) 04:52, 13 May 2016 (UTC)

The reason I wrote this question here is because I would like to ensure it with science. Is it right scientifically that the fox is such cleaver? 93.126.95.68 (talk) 04:54, 13 May 2016 (UTC)

Don't predators in general seem to be "smarter" than their prey? Prey are better known for being prolific than for being smart. The average cat might be smarter than the average mouse, but there are a lot more mice. ←Baseball Bugs ^{What's up, Doc?} carrots→ 07:06, 13 May 2016 (UTC)

As the Kzinti say, "How much intelligence does it take to sneak up on a leaf?" {The poster formerly known as 87.81.230.195} 185.74.232.130 (talk) 14:04, 13 May 2016 (UTC)

• Animal intelligence is fiendishly hard to quantify (indeed, even human intelligence is fiendishly hard to quantify...) Wikipedia does have an article titled Animal cognition which gives a nice overview of the science. Perhaps starting there will lead you interesting directions for your research. --Jayron32 12:10, 13 May 2016 (UTC)

Once an animal becomes the symbol of some particular anthropomorphism, that tends to continue even if science might cast doubt on it. The idea that the fox is cunning goes back over 2000 years (the first literary reference is Aesop) so was probably based on popular observation, rather than on what we could consider scientific study. 81.132.106.10 (talk) 12:15, 13 May 2016 (UTC)

It is worth noting that it isn't just Western culture. Foxes have long been regarded as highly intelligent tricksters in the cultures of China and Japan as well (e.g. kitsune, huli jing). Dragons flight (talk) 12:31, 13 May 2016 (UTC)

As far as tricksters go, "Living Sideways: Tricksters in American Indian Oral Traditions" says "Coyote is no doubt the best known of the animal tricksters, but there are many others: Raven, Mink, Fox, Blue Jay, Skunk, Coon, Spider, Dragonfly, Turtle, Mud Hen, Wolf, Rabbit, Canada Jay, and Wolverine". The book goes on to discuss some theories about why those animals were chosen, but it appears that no one knows. I'll also point out that Genesis 3:1 says that the serpent is the craftiest of the animals. So there may be nothing special about foxes. -- BenRG (talk) 19:50, 13 May 2016 (UTC)

Humans consider the Fox a pest for his opportunistic attacks on poultry and rabbits, resistance (usually) to domestication and wiliness at concealment that makes him difficult to track and hunt. In the Lotka–Volterra equations that model predator-prey species interaction the variable y is typically the number of foxes. This article discusses Foxes in popular culture. As early as 600 BCE Aesop told a story about a dishonest greedy fox. Machiavelli wrote that the successful prince must have the traits of both the lion and the fox. In English dictionaries we find:

FOX (noun) someone who is clever at tricking people, a shifty deceptive person

TO FOX (verb) to make you confused and be impossible for you to understand or solve. Etymology from 1660s is "to delude" implied in Old English verbal noun foxung "fox-like wile, craftiness;" and Middle English had foxerie "wiliness, trickery, deceit."

SHENANIGAN (a deceitful confidence trick, or mischief) is considered to be derived from the Irish expression sionnachuighim, meaning "I play the fox." AllBestFaith (talk) 12:40, 13 May 2016 (UTC)

I think BenRG is correct above. I'll add that there can be different animals for different kinds of cleverness, such as the distinction between the clever conniving predatory fox and the clever stealthy resourceful respectable coon. This is kind of hinted at in one of Melville's wierder works [16] but I think it is also a broad part of early American culture; part of this I think is also based on a point that I'm still not sure about that the red fox was believed to be (and was it??) of foreign origin, whereas the coon was an American native. So you can see old political cartoons of the Whigs, and especially Abraham Lincoln, who was Whig before he started his own descendant party, drawn as coons - their opposition to slavery eventually led to "coon" being used as a perjorative term for blacks, though one, given its original positive meaning and the sort of skills that their communities needed to develop to survive injustice, was oddly apt, though I would not nonetheless expect to get a favorable reaction anywhere in the country if using it! But I fear that in modern America there is much too much singing of the praises of foxes, and not so much of coons, in any sense at all. Wnt (talk) 22:35, 13 May 2016 (UTC)

Let's compare foxes with other similar-sized mammalian predators. There are cats and dogs, both thought to be fairly intelligent, but those living with people may have less need to be clever to survive (would you really kill you dog if he can't learn any tricks ?). Wolves live in packs, so may have less need for a certain type of cleverness needed by a solitary hunter. Coyotes are also thought of as clever, and also tend to live solitary lives. Then there was the popularity of the fox hunt, which no doubt led hunters to exaggerate the skill of their quarry in order to boost their own standing. StuRat (talk) 23:01, 13 May 2016 (UTC)

This claim about the fox hunt seems sketchy. It seems like all the skill of tracking and cornering the quarry is that of the dogs, and the rich English guy rides along behind them to claim credit for their work after the fact, much as in his business enterprises. Wnt (talk) 02:49, 14 May 2016 (UTC)

Whose prejudices are showing now? It's not only rich people that hunted foxes - many less well off country people got involved too. In the Lake district they traditionally hunted on foot so you didn't even need to own a horse. Richerman (talk) 08:56, 14 May 2016 (UTC)

The only remotely academic reference that I could find was Friendly foxes are cleverer: Domesticated foxes show evolution of social intelligence by Emma Marris, which seems to refute StuRat's assertion above that "those living with people may have less need to be clever". Alansplodge (talk) 00:18, 15 May 2016 (UTC)

I was talking about evolution, which takes many generations, so unless foxes have been domesticated as long as cats and dogs, and to the same degree, there will have been little evolutionary change to them. Also note that social intelligence is just one type. It's quite possible that their ability to hunt and evade being hunted goes down at the same time their social intelligence goes up. StuRat (talk) 01:00, 15 May 2016 (UTC)

If anyone suspects one is unintelligent, one has a choice between remaining silent or opening one's mouth to prove it. So let's ask What does the fox say? (video) AllBestFaith (talk) 11:16, 15 May 2016 (UTC)

Going back to the original question, I thought that it was another mammal species that was always considered to be the smartest or cleverest...i.e. Homo sapiens. DrChrissy ^(talk) 13:54, 16 May 2016 (UTC)

It wasn't about "another mammal species". It was about the other mammal species. I guess that excludes us. It's not just mammals that are smart. Recent studies have shown that birds are pretty intelligent, despite their small brain size. Although they don't have a cerebral cortex, their alternative wiring is just as effective. 80.44.167.65 (talk) 15:00, 16 May 2016 (UTC)

I guess that depends on the way you read it. My interpretation is that because the question did not specifically exclude humans, and we are undeniably mammals, we are among the "other mammals". I agree with you totally about birds and their intelligence, particularly the corvids. I have recently created Theory of mind in animals where birds feature heavily and the Mirror test is also rather revealing. DrChrissy ^(talk) 15:31, 16 May 2016 (UTC)

How being a veterinary work?

How being a veterinary works?
I mean to take care of humans you need do to medicine to be a doctor, thats an entire course to deal with just one single specific living being, the homo sapiens sapiens (and doctors dont deal with ALL areas of human medicine, they have their specific areas), but a veterinary have to deal with every single other specie that exist on this entire earth.201.79.54.252 (talk) 12:44, 13 May 2016 (UTC)

• Veterinary physician has an overview. Veterinarians often specialize in certain disciplines, such as can be seen at Veterinary physician#Focus of practice. No veterinarian would be expected to treat every single kind of animal, and instead specialize by category. --Jayron32 12:48, 13 May 2016 (UTC)

Bear in mind also that vets do not have the same pressure to try and save the patient's life at any cost: if the condition is too serious, or the treatment too expensive for the owner, a lethal injection is an option that no doctor would have when treating a human patient. 81.132.106.10 (talk) 13:44, 13 May 2016 (UTC)

Adding to what Jayron32 has said, sometimes doctors and other (human medical specialists) are called in to assist with procedures particularly on apes but also other non humans mammals see e.g. [17] [18] [19]. However these are the exception, in normal cases it is veterinarian although as Jayron32 and the article say, it's not true that all vets normally treat all animals or all types of problems, there are specialisations based on type of animal and procedure. Besides our article, see e.g. [20]. Nil Einne (talk) 17:07, 13 May 2016 (UTC)

All veterinarians are competent over a large range of animals (including humans..your typical vet could work in an emergency room during a disaster etc), like an internist...but there are all kinds of specialists too (ie horses, marine animals etc)..68.48.241.158 (talk) 13:49, 13 May 2016 (UTC)

(Personal anecdote) I've had pet rats for over 10 years. I have found that many veterinarians won't treat rats. I assume the same is true for other exotic pets. It took a while to find a vet who was both willing to treat rats and was knowledgeable about them. A vet once told me that there's a joke among veterinarians: "doctors are veterinarians who only treat one kind of animal." CodeTalker (talk) 19:08, 13 May 2016 (UTC)

as a kid the vet we took our dog to never had a problem looking at my hamster or iguana..prescribed something for an eye infection iguana had...they understand animals like this quite well...these are knowledgeable scientists with a lot of schooling...of course 90% are dealing with cats/dogs/horses/farm animals/cattle regularly..68.48.241.158 (talk) 20:12, 13 May 2016 (UTC)

Someone with no feeling below the ~diaphragm (because of a spine injury) remarked that he might do better going to a vet, because they're accustomed to not being able to ask the patient how something feels. —Tamfang (talk) 23:39, 15 May 2016 (UTC)

This article will give you a good idea of what is required to become a qualified veterinary surgeon in the UK. Richerman (talk) 09:19, 14 May 2016 (UTC)

May 14

A method to scientifically test the existence of god

A lot of people have near death experiences, where in some cases they report seeing doctors trying to revive them and said they heard/seen things around them during the time "they died". if there was something very definite they can verify, e.g. putting a 6 digit number out of the sight of the dead body, but would be clearly visible from another angle, and if they can recall the number after they get revived, that would prove existence of afterlife and therefore of god. these tests can be run on death row inmates, kill them in a way that it's possible to revive them (e.g. anaesthetic overdose), and say if they can recall the number then they'll get life sentence instead of death (for some incentive).

This is the single most important question in human history, and we have the means to test it. So why haven't we done it? — Preceding unsigned comment added by Money is tight (talk • contribs) 00:33, 14 May 2016 (UTC)

Would you change your behavior if you would have proof that (a) god did or did not exist?

I don't think that that question is very important, it is quite irrelevant to me, and I don't think that the existence of an afterlife would be proof for the existence of a god or gods. People have scientifically tested the existence of a god, and the conclusion was that there is no reason to believe in a god or gods.

For example, back in 1872 Francis Galton concluded that prayer does not work, because the life expectancy of the British royals was not higher than that of the rest of the population despite weekly prayer for their health, and that churches burned down, got hit by lightning and destroyed by earthquakes at the same rate as other buildings of a comparable size. The Quixotic Potato (talk) 01:05, 14 May 2016 (UTC)

One of Isaac Asimov’s essays notes that when the lightening rod was invented, churches were reluctant to install them, as it would be attempting to thwart God’s vengeance. They gradually came around when they noticed the brothels and taverns being spared by the rod, while churches burned to the ground. Willondon (talk) 16:45, 15 May 2016 (UTC)

Or one could draw the conclusion that God wants to be worshiped in a rather different fashion than we imagined. It's not unprecedented. StuRat (talk) 16:40, 16 May 2016 (UTC)

(EC) Well, first, it has been done, though in a less grizzly fashion than you suggest - see the first three or so paragraphs at Near-death_experience#AWARE_study. As to your suggestion, there are major ethical problems in experimenting with death in the way you suggest, besides the whole idea being abhorrent. And then there's the point that even did the test pan out - near dead person sees something his body could not have seen - you have not proved god, but merely got yourself an observation for which it is difficult to construct an explanatory mechanism. All ethical and practical considerations aside, those who do not believe in god are unlikely to mount this test, since the anticipated absence of evidence (of god) is not evidence of absence - in other words, nothing gets proved by the experiment. Those who do believe in god are unlikely to put her to the test in this fashion. So the potential queue to perform the experiment is very very small indeed. --Tagishsimon (talk) 01:11, 14 May 2016 (UTC)

Houdini had a famous test where he told his wife some keywords that she had to memorize, and said he would tell them to any psychic who truly contacted him after his death. He died, and many psychics claimed to have contacted him, but none knew the keywords. Draw your own conclusions. StuRat (talk) 01:13, 14 May 2016 (UTC)

Houdini, dead ? What if the psychics could never have told her the special keywords ? ..the same result.. would occur.. --Askedonty (talk) 19:15, 15 May 2016 (UTC)

Some years ago a psychic was scheduled for an appearance on the local radio station. She arrived late, and said she was "caught in traffic." Apparently her psychic abilities did not include traffic reports. ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:38, 15 May 2016 (UTC)

They usually weasel out of this by saying they can't predict everything, 100% of the time, which is of course true, if quite an understatement of what they can't predict. StuRat (talk) 16:35, 16 May 2016 (UTC)

a fundamental problem too is that any experience of God still runs into the problem of Descartes radical doubt: Cogito ergo sum 68.48.241.158 (talk) 02:04, 14 May 2016 (UTC)

How is Descartes' belief in his own existence a fundamental problem? AllBestFaith (talk) 13:52, 14 May 2016 (UTC)

it's related to the notion of radical doubt..that is, even if one had the experience of God appearing before her etc, there's no way to no for sure that this is really what is occurring...one could be being fooled by an entity other than God etc etc...just as our experiences could be something other than what they appear..see "brain in a vat" etc etc...68.48.241.158 (talk) 14:13, 14 May 2016 (UTC)

Far from succumbing to despairing that everything is doubtful as you suggest, René Descartes who was evidently a male person who served in the army and fathered an ill-fated illegitimate daughter Francine, turned his ability to doubt into the tool of methodological skepticism with the goal of sorting out true from false claims. Since Descartes considered himself to be a devout Catholic, though his attempt to ground theological beliefs on reason encountered intense opposition, you may be doubly mistaking him for an atheist female. AllBestFaith (talk) 14:48, 14 May 2016 (UTC)

you seem to somehow have confused my use of the female pronoun in my example as suggesting Descartes was himself female...this would be an instance of poor reading comprehension..regardless, what I describe is accurate and has relevance..68.48.241.158 (talk) 15:00, 14 May 2016 (UTC)

There is no reason to assume that an afterlife requires the existence of God, or vice versa. ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:33, 14 May 2016 (UTC)

Agreed. The OP needs to think about what the hypothesis is and what the experiment is here. It is possible to picture a worldview in which there is an afterlife without God, or without a noticeable God. It is also very possible to imagine an afterlife that does not involve having some kind of disembodied vision. I mean, think about it - the colors we see are the product of red, green, blue receptors of a certain frequency. Our vision has a certain acuity, fails to pick up far infrared or (usually) ultraviolet. For that vision to be replicated after death by something that is invisible - i.e. which does not absorb light - seems extraordinary. Testing this kind of remote viewing has been attempted by some very unexpected agencies - see Project Stargate; there's no reason to assume a person would have to be dead to do it, if these disembodied eyes are part of some soul that exists in a living person also. Wnt (talk) 02:47, 14 May 2016 (UTC)

posting of banned user removed. The Quixotic Potato (talk) 12:27, 16 May 2016 (UTC)

Because a car manual contains accurate and useful information, it is not a work of fiction. The Quixotic Potato (talk) 09:46, 15 May 2016 (UTC)

The Bible is the designer's manual for use by humans? That view clearly reflects the belief system you have been given, and adopted, but your belief system is just one that has been created to date, and it is significantly different to the belief systems adopted by many others around the world. Dolphin (t) 10:58, 15 May 2016 (UTC)

Whether we could prove "scientifically" that God exists, in the end, You will either believe Him without such proof, or You won't, and I do not believe such proof can be found in this Age, since the Just shall live by Faith. Chris the Russian Christopher Lilly 09:21, 15 May 2016 (UTC)

The motor manufacturers set out to provide practical information in their manual. Why would you assume that the object of the people who put together the Bible was to tell a fairy story? As for the efficacy of prayer, if you pray that you will win the lottery you might not have much luck, but if you were to pray that a close relative be delivered from a serious illness you might be more successful.

posting of banned user removed. Fut.Perf. ☼ 08:15, 16 May 2016 (UTC)

Are you trolling? Shouldn't you be a lot more humble? Are you allowed to judge others? I noticed you haven't apologized yet. Praying for a sick relative is a waste of time. It is far better to bring them to a hospital, or call an ambulance. In the hospital they don't pray for the patient, they actually do useful stuff, like giving them medicine. There is a reason that god does not heal amputees. Your idea of god is just as made up as all the others. It is 2016, why do you still believe that nonsense? The Quran, Torah and Bible are all the same story about the same idea of a god, and the differences between them are quite small. I've read all three, maybe you should too! God loves atheists. The Quixotic Potato (talk) 12:03, 15 May 2016 (UTC)

“ Fuck me Sam, what are the odds
That of history's endless parade of gods
That the God you just happened to be taught to believe in
Is the actual God and he digs on healing,
But not the AIDS-ridden African nations
Nor the victims of the plague, nor the flood-addled Asians,
But healthy, privately-insured Australians
With common and curable lens degeneration ” — Tim Michin

posting of banned user removed. Fut.Perf. ☼ 08:15, 16 May 2016 (UTC)

Translated into English????? What are you talking about? You have not answered my questions. Are you trolling? Shouldn't you be a lot more humble? Are you allowed to judge others? And you haven't apologized yet. Don't worry, I'll forgive you, and I will ask your god to forgive you because you obviously don't know what you are doing. The Quixotic Potato (talk) 12:56, 15 May 2016 (UTC)

posting of banned user removed. Fut.Perf. ☼ 08:15, 16 May 2016 (UTC)

I wrote: "Translated into English?????"... You seem to know very little about the Bible (you wrote: Part of the Bible is the Torah (translated into English).), and religion in general (you wrote: How can a religion not have "a god or gods"?). Have you read the bible? How old are you? People do continue to visit Lourdes even though they don't derive benefit from it (or, you know, no miraculous cures). You have not answered my questions. Are you trolling? Shouldn't you be a lot more humble? Are you allowed to judge others? Have you read my userpage? What is your accountname? You should read this and watch this and that and this too. Have you read [21], [22] & [23]? The Quixotic Potato (talk) 13:45, 15 May 2016 (UTC)

Can someone close this thread and collapse the against policy behavior of "Quixotic Potato" and whoever else he's been engaging with??68.48.241.158 (talk) 14:14, 15 May 2016 (UTC)

Hahahaha. Welcome to the Science reference desk mate. Your most recent block ended 2 weeks ago, maybe it is a good idea to improve some articles? The Quixotic Potato (talk) 14:15, 15 May 2016 (UTC)

Some of the comments above go beyond the scope of the original proposed method, but they have some of the same issues regarding their hypotheses. Testing the existence of God by praying for healing assumes, for example, that, despite creating it, God doesn't see any beneficial use for disease; it also assumes that the purpose of prayer is to make magic happen rather than, for example, to provide insight or inspiration. Reifying "the Bible" minimizes the fact that it is made up of different books by different people that were independently circulated. So there is much needless conflict produced because people are taking a very specific notion of religion and then saying either it is all true or it is all false, when maybe the most important bits are independent of the most testable bits. After all, the most significant form of healing is resurrection into a new and better universe, yet it is clearly not possible to tell whether such a thing could occur by ordinary scientific means of investigation. Wnt (talk) 18:59, 15 May 2016 (UTC)

FYI, an IP is yelping at WP:ANI about this section, if anyone wants to comment there. ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:04, 15 May 2016 (UTC)

Actually, praying for the sick or for anything else does work. For sure, one must use the Medical Knowledge God has also allowed us, but the effectual fervent prayer of a righteous man availeth much, and thus Prayer is indeed useful, and may even accomplish what even Modern Medicine cannot. The Bible would not say such things if they were not true - and by the way, all of the Bible is true, does not matter what one can, or what one thinks one can prove "scientifically". What I see in some of these attempts to prove the Bible by Science ends up being reducing God's real Miracles to natural acts that can be explained away. As for judging, one can only do so if they are not doing the same things wrong. If one has genuinely turned to God, it should only be because they have first judged themselves in the Light of God's Word, as Judgment must begin at the House of God. But judging others should only be according to God's Righteous Judgment. Whether or not is 2016, and even that Number we use for this year is based on timing with respect to the Bible, that is to say, it is said to be about 2016 years since the Birth of Christ ( when I understand He might actually have been born around September, 4 BC ), whether or not indeed it is 2016, or whatever year it happens to be in any given moment, as people have said such things up to now, should have no bearing on our Belief in God, or any lack of it, since Jesus Christ is the Same, yesterday, today and forever, and whatever people think about Belief in Him being out of Date, it never is. His Word, which endureth forever, is just as valid now as it ever was or will be. It is also interesting that when things go wrong, People blame God, and yes, nothing happens that He does not ultimately allow, since if He wished, He could stop it, but the same People might not thank and praise Him for all that He has done and created that is Good - He gets a lot of the blame, but hardly any of the Credit, and think of it, if we live in a World which in general does not honour Him, does not run things in the Way He in His Wisdom knows and commands they should be run, we ought not be surprised if He allows unfortunate events to occur. But the thing is, if we all did turn to Him, He would hear us, and forgive us ( 2 Chronicles 7:14 ), because He does not bear a grudge against those of us here on Earth who still have a Chance to turn to Him. May God forgive us all for each and all of our own sins, for there is none that sinneth not, and I would not presume to speak of God if I had not acknowledged my own sins to Him. To finish - He knows and hears all, and whatever we say or write, we will give account, and I can only pray that if we have offended Him, we can admit that, and turn to Him. One way or other, in the end, when all is said and done, whether or not we think God exists, we will find out for sure. Chris the Russian Christopher Lilly 00:39, 16 May 2016 (UTC)

I'm late to the party, but no one has yet mentioned at least one serious attempt to approach this exact question God: The Failed Hypothesis by Victor_J._Stenger. If you are at all interested in this subject, I can recommend this book, I found it quite interesting and informative. Vespine (talk) 06:18, 16 May 2016 (UTC)

1. Any experiment involving killing human subjects is unlikely to pass ethical standards.
2. The experiment proposed wouldn't answer the question. At most it could prove that, at the point of death, your soul/spirit/consciousness leaves the body and can see things that you couldn't while still in your body. It wouldn't prove that the soul was immortal (maybe it evaporates a few minutes after body death), nor that it can "pass on" to some sort of after life, not that there is a God or gods. And it certainly won't prove which of the many proposed gods and after-lives is the correct one.
3. Also, the idea that your "soul" can see things after it leaves the body would raise some other problems. Like, why do you need eyes to see while your soul is still inside its body? If the soul can see without eyes, what is the point of them? And if the soul's movement is trapped by its body, and its vision is blocked by flesh, what else blocks it? How does it get out of the room to wherever it is supposed to go? Iapetus (talk) 10:45, 16 May 2016 (UTC)

Could an asteroid be ring-shaped ?

I picture a spherical asteroid, struck dead-on by a small, fast moving object, that punches a hole through it. Somehow I doubt if that would work, though, either breaking the asteroid into many fragments or melting it, in either case allowing it to coalesce back into a sphere. Maybe if the asteroid was flattened out from a high spin rate and the object struck it right on the axis ? StuRat (talk) 01:41, 14 May 2016 (UTC)

If the spin rate an dcollision speed were fast enough for the material to not coalesce in a sphere, it would be dispersed entirely. Fgf10 (talk) 12:27, 14 May 2016 (UTC)

Toroidal planets are possible, but they are not highly stable. A large impactor will cause them to collapse. So such a body is possible, but it has to coalesce from a primordial cloud with a high spin, and can't be created by the specific method StuRat proposes. (I only just found this out recently, but couldn't recall my source.) μηδείς (talk) 16:45, 14 May 2016 (UTC)

For future reference (since the search results will likely change) the leading search results include [24], [25], [26]. I remain less than confident this is possible from what I've read so far, but they think so and I can't rule it out. Wnt (talk) 19:13, 15 May 2016 (UTC)

Couldn't an exceedingly improbable string of tiny impacts "sculpt" an asteroid a few meters wide into a ring? Sagittarian Milky Way (talk) 19:45, 14 May 2016 (UTC)

larva on Mentha

Hey everyone, I found this larva on my Mentha. I try to identify this creature. I would glad to some help. I think it is a Chrysodeixis eriosoma but I'm not sure. thanks alot, --Tomsky2015 (talk) 09:22, 14 May 2016 (UTC)

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Well, there aren't many characters I'm really using here: I see it has three pairs of prolegs, and it's green, and it moves like an inchworm or looper. Without looking at your suggestion (which also fell in this category), I noted that some loopers in Noctuidae have three pairs of prolegs, such as the cabbage looper. (That, like yours, seems too fat to my eyes) There are various Noctuidae that come up on Mentha, but so far I didn't see a green one - it's not really easy for me to search. Pending some insight on how to find a better key, I think I'll leave this for now. Based on the lettering, is this from Israel, or somewhere else? Wnt (talk) 11:17, 14 May 2016 (UTC)

Wnt, Yes, Israel. Thank you very much. I looked on internet to see if I will find it by myself. My best result was Chrysodeixis eriosoma but your suggestion look right. Thank you and good day. --Tomsky2015 (talk) 12:45, 14 May 2016 (UTC)

Formulaic relation between two units

Suppose we don't know the simple formula to convert Centigrade into Fahrenheit or vice-versa. But, some how , we do know two or three instances of relationship between the two units. For example we know for sure that 5°C equals 41.0 °F, 17°C equals 62.6 °F, whereas 45°C is equal to 113.0 °F. My question is that, using these few instances how can we come up with a simple formula that can be used to turn any value of C or F to it's corresponding equivalent. 124.253.250.54 (talk) 12:16, 14 May 2016 (UTC)

Yes, provided we know that there is just a multiplication factor and a constant offset. It then becomes a simultaneous equation problem:

We only need two equations:

   45m + c = 113
    5m + c = 41

Now multiply the 2nd equation by 9 and subtract the 1st equation from it:

  (5m +  c = 41)×9
  45m + 9c = 369
-(45m +  c = 113)
        8c = 256

Solve for c then plug that back into the 2nd equation to solve for m:

         c =  32

   5m + 32 = 41
   5m      =  9
    m      =  1.8

Note that temperature conversions are a bit unusual in that they have a constant offset (except the conversion between Rankine and Kelvin). Without that you only need one conversion to find the multiplication factor, m. Similarly, you only need one conversion to find the constant offset, if there is no multiplicative factor (in other words, if it is 1, as in a Celsius to Kelvin conversion or Rankine to Fahrenheit). StuRat (talk) 12:44, 14 May 2016 (UTC)

All correct, we only need use two equations IF we already suspect the relationship is linear with an offset. The OPs third equivalence serves to confirm that. AllBestFaith (talk) 15:41, 14 May 2016 (UTC)

Yes, it's always a good idea to check your work by plugging the results into all equations provided. StuRat (talk) 16:50, 14 May 2016 (UTC)

Side note is that the mathematical definition of "linear" is there is no offset. --DHeyward (talk) 08:22, 15 May 2016 (UTC)

The only reason why you know there is a linear relationship is because Celsius (since 1948 the preferred term, even though the guy had the scale backwards) and Fahrenheit are defined the same way, just with different numbers. Wnt (talk) 10:58, 15 May 2016 (UTC)

Some people, especially less technical or elderly ones, need a Mnemonic to help them remember the conversions between °C and °F. They may remember the constants 5, 9 and 32 which appear in both formulæ but not how to apply them. That incomplete memory leaves one in this quandary about converting:

Subtract 32 or not ?

Multiply by 5/9 or by 9/5 ?

Add 32 or not ?

The rule that works is: Make the 3 choices above that each ensure numerical °F is "warmer" than numerical °C. "Warmer" here means more positive number, which is true for all temperatures except minus 40 degrees and below, which is colder than you want to think about. AllBestFaith (talk) 23:33, 15 May 2016 (UTC)

The choice is easy between 9/5 and 5/9. Celsius degrees are larger than Fahrenheit ones, so when changing from Celsius multiply by 9/5 and when changing from Fahrenheit multiply by 5/9. For those who have problems with adding or subtracting 32 there is a formula which makes use of the fact that -40 is the same in both scales. Using the fact that 10 degrees C = 50 degrees F and looking for easy divisions I reconstructed it as follows:

• Fahrenheit to Celsius

Add 40. Multiply by 5/9. Subtract 40.

• Celsius to Fahrenheit

Add 40. Multiply by 9/5. Subtract 40. — Preceding unsigned comment added by 5.150.93.133 (talk) 09:13, 16 May 2016 (UTC)

I think it's easier to remember that freezing is 0 C and 32 F. If you can remember that 212 F = 100 C and understand 212 = 180 + 32, you're golden. Wnt (talk) 17:00, 16 May 2016 (UTC)

Would dynamic tension work in space?

Dynamic tension is about contracting your muscles and moving them against each other Dynamic_Tension Would astronauts be able to use it to stave off bone loss and keep healthy? Bastardsoap (talk) 16:20, 14 May 2016 (UTC)

Yes, but it might be difficult to keep tabs on them. You would need to put a strain gauge between their hands to tell how much force they are really exerting, while a stationary bike is easier to monitor. Also, dynamic tension exercises don't do as much cardio, and that's important, too. StuRat (talk) 16:47, 14 May 2016 (UTC)

It's not that hard to add cardio with dynamic tension, you just have to contract less and do more reps Bastardsoap (talk) 17:31, 14 May 2016 (UTC)

I'm skeptical that you can get your heart rate up and keep it up as long as on a stationary bike. StuRat (talk) 17:41, 14 May 2016 (UTC)

Try a ddp yoga workout and see for yourselfBastardsoap (talk) 17:59, 14 May 2016 (UTC)

Its not a substitute for gravity and therefor this is still a well known health issue for long missions. Besides that gravity also completely affects cords and tissue and you can not substitute all that just with "some gymnastics". For that you find extensive artificial gravity constructions in Spacevessels in better Sci-fi movies like 2001: A Space Odyssey (film). --Kharon (talk) 12:14, 15 May 2016 (UTC)

A better solution would be a rotation that creates a 1G force. Exercise may help certain muscle tone and bone density but balance seems more important. To wit, a 150lb, 6 foot man can walk. So can a 300lb, 6ft man. I wouldn't expect that giving a 150lb backpack to the 150lb man would make him equivalent to the 300lb man in their ability to function. Both have adapted to their condition. --DHeyward (talk) 09:15, 16 May 2016 (UTC)

There are several disadvantages to a ship rotating fast enough for 1g:

1) Unless it's a large radius, the difference in g force when you stand up will induce nausea.

2) You lose the advantage of astronauts being able to move large pieces of equipment on their own.

3) Docking can only happen at 2 points, along the axis, and then you still need to match the rotation.

4) EVA's on the outside of the ship to do maintenance while it's rotating are impractical, so then you need to be able to stop the rotation and restart it, using up fuel.

5) Solar panels and communications antenna need to be moved constantly, to keep them aimed at their targets, causing them to break down sooner. The communications problem could be solved by having a sister ship which doesn't rotate, to do all the long distance communications, but that would require station keeping to keep them apart, and maintenance wouldn't be easy there. StuRat (talk) 15:53, 16 May 2016 (UTC)

Well, a lot of sci-fi designs suppose a limited centrifuge space for exercise with large nonrotating sectors at either end, to which ships dock. The centrifuge has limited uses that don't require much heavy equipment or stuff on its outer hull. Of course, given the stress involved I'd think you'd still have to check that hull for cracks and fatigue, which involves EVAs; but in theory the angular momentum can be transferred to a flywheel or to one of the end pieces or a second centrifuge section (rotating the other way) without the need for propellant usage, just electricity. Wnt (talk) 17:04, 16 May 2016 (UTC)

There the joints between rotating and non-rotating parts become risky, and an astronaut entering or leaving the rotating part needs to spin up or spin down their body. StuRat (talk) 17:11, 16 May 2016 (UTC)

It's not that simple. According to NASA "the risks of these problems occurring [bone loss and kidney stones] cannot be completely eliminated through physical exercise alone." [27] Richerman (talk) 22:45, 16 May 2016 (UTC)

Measuring calories

I heard somewhere that scientists determined the number of calories in carbohydrates, fats, and proteins by measuring how much heat the body produced after eating. I know scientists have burned carbohydrates, fats, and proteins in a calorimeter and found a discrepancy between how much heat is released when protein is burned in a calorimeter and how much energy is produced when protein is metabolized in the body. The body gets 4 calories per gram from proteins, but burning a gram of protein in a calorimeter yields considerably more energy. How do scientists know how many calories the body gets from a nutrient like protein?174.131.47.80 (talk) 18:37, 14 May 2016 (UTC)

Yes, there is a problem using a bomb calorimeter (or any other type), in that not everything that's flammable is digestible, with an obvious example being wood. I wouldn't think measuring heat produced by a person following a meal would work, either, though, as then you have confounding factors like the amount of food energy stored as fat to be burnt later, or retrieved from fat stored from previous meals. I would think using mice for this test would be better, since presumably they can digest about the same things we can, and you could feed them an all-protein, all-carb, or all-fat diet for their entire (short) life without violating medical ethics (although PETA might not like it). StuRat (talk) 20:34, 14 May 2016 (UTC)

The gross energy (GE) of a food, as measured by bomb calorimetry is equal to the sum of the heats of combustion of the components – protein (GE_p), fat (GE_f) and carbohydrate (GE_cho).

${GE}={{GE}_{p}+{GE}_{f}+{GE}_{cho}}\,$

Wilbur Olin Atwater 1844 - 1907 considered the energy value of faeces in the same way.

${GE}^{F}={{GE}_{p}^{F}+{GE}_{f}^{F}+{GE}_{cho}^{F}}\,$

to develop the Atwater system for calculating the available energy of foods:

${\text{Metabolisable Energy}}=\left({\text{Gross Energy in Food}}\right)-\left({\text{Energy lost in Faeces, Urine, Secretions and Gases}}\right).$

AllBestFaith (talk) 23:56, 14 May 2016 (UTC)

Amino acids are not completely cataboilized by animals. Therefore the bomb calorimeter significantly overestimates their biologically relevant energy content due to the energy remaining in urea. Ruslik_Zero 08:06, 15 May 2016 (UTC)

There are also whole room calorimeters that you can stick a person in, and control the gases and other materials coming in and out while also taking measurements. --OuroborosCobra (talk) 00:13, 17 May 2016 (UTC)

May 15

H2CL2

Why does this here [28] is 2HCL but not H2CL2 ? --Ip80.123 (talk) 01:02, 15 May 2016 (UTC)

It is dichloromethane, there is a "C" (carbon), that is not labeled, in the center of this skeletal diagram. And it's completely not true that the two H are "across" from each other or at right angles to the two Cl and vice versa. Our article has some nice 3D diagrams of the shape of this chemical, a detail that is easy to mis-understand in the image you found. DMacks (talk) 02:14, 15 May 2016 (UTC)

The Implicit carbon and hydrogen atoms section of the above article is the most important. LongHairedFop (talk) 16:54, 15 May 2016 (UTC)

Where are Salmonella bacteria are founded in the eggs?

Sometimes I hear about the risk to consume eggs in some places in the world since they contains a high level of salmonella. Where are Salmonella bacteria are founded or located in the eggs, are they founded on the shell from outside or into the eggs or maybe both places? (it matters for example, for case that we can wash well the eggs with soap)93.126.95.68 (talk) 06:18, 15 May 2016 (UTC)

See Salmonellosis#Causes, which says that an infected hen can transmit the bacteria to eggs she produces, or bacteria can enter the egg through the shell. Egg shells contain small pores to allow in air for the embryo to "breathe". --71.110.8.102 (talk) 06:59, 15 May 2016 (UTC)

The U.S., Japan and a few other countries do wash them for that reason but then you need to keep them refrigerated.[29] Rmhermen (talk) 12:52, 15 May 2016 (UTC)

If you wash an egg with soap then the soap can get inside... The Quixotic Potato (talk) 13:13, 15 May 2016 (UTC)

In Israel it's forbidden to wash eggs in water according to the health minister (this is for public places) and for the citizens it's not recommended, because the bacteria can get inside through the shell. I would like to know about other countries. 93.126.95.68 (talk) 03:23, 16 May 2016 (UTC)

Same here, in the Netherlands, it is not recommended (but I don't know if its forbidden in public places). Washing eggs is a bad idea. My brother has pet chickens. If you google "wash eggs" you will find many sites that all say something similar to this: "Eggs are laid with a natural coating on the shell that is applied as the last step in the laying process called the "bloom" or sometimes the "cuticle". This coating is the first line of defense in keeping air and bacteria out of the egg. Since eggshells are porous, if you wash your eggs as soon as you collect them, you are removing that natural barrier." [30] The Quixotic Potato (talk) 12:01, 16 May 2016 (UTC)

This PDF says: Current European Union legislation prohibits the washing of Class A eggs. The Quixotic Potato (talk) 12:09, 16 May 2016 (UTC)

Here are the recommendations from the Food Standard Agency in Ireland regarding egg washing.[31] DrChrissy ^(talk) 16:03, 16 May 2016 (UTC)

This is a rather informative, non-technical account of the pros and cons of egg washing.[32] DrChrissy ^(talk) 16:07, 16 May 2016 (UTC)

Looking for the Full List

Over ten years ago, I read a tract in which the Author spoke of seven, what I believed he called, principles of engineering, or principles of mechanics, and named them as the cog, hinge, lever, pulley, screw, spring and wedge. I think what we was saying was that these were the seven foundations of mechanical movement, and I wonder, whether there were more, and also, if anyone else has heard of such a list, and what it was called. I could think also of the wheel, the ball, a ball and socket joint, although that could kind of be thought of as some specialised kind of hinge, bearings, couplings, nails, chains, among other things. But perhaps the list was about such things at their most basic level, where these become the basic parts to more complicated machines. I suspect also that the rubber band is seen as a kind of spring, at least in a more basic sense. If anyone has any other information on this, that would be good. Thank You. Chris the Russian Christopher Lilly 06:34, 15 May 2016 (UTC)

Simple machines. Sagittarian Milky Way (talk) 06:39, 15 May 2016 (UTC)

Thank You for that.Chris the Russian Christopher Lilly 00:39, 16 May 2016 (UTC)

Nostrils--- one or two?

Both my nostrils have been clear for the last couple of months. ie I can breathe thro both of them at the same time. Is this normal? I seem to remember reain on a WP page that nostreils alternate in being clear for operation. Is that statement false? — Preceding unsigned comment added by 178.106.99.31 (talk) 17:44, 15 May 2016 (UTC)

Yes sorry I forgot to sign.,--178.106.99.31 (talk) 17:46, 15 May 2016 (UTC)

See Nasal cycle. However, although there is a regular alternation, most people are not acutely aware of one nostril being blocked and the other open. If you feel that one nostril is blocked for a longish period, you have a problem. 81.132.106.10 (talk) 17:55, 15 May 2016 (UTC)

Both my nostrils have been clear for a few months. Is that usual?--178.106.99.31 (talk) 17:57, 15 May 2016 (UTC)

It's unclear whether asking why no one has punched you lately or telling you to read our guideline against medical advice would be more helpful. μηδείς (talk) 19:03, 15 May 2016 (UTC)

I dont think my inferior turbinates are undergoing alternating complete turgescence as far as I can tell at the moment. Am I fooling myself,or is it that I am in the 20% of the population that does not exhibit alternating turgesence? Or is it possible that I only experience partial turgesence in either nostril?--178.106.99.31 (talk) 22:56, 16 May 2016 (UTC)

Gas analysis

Can it be told what is wrong with a persons body by analising the anal gas emanations?--178.106.99.31 (talk) 17:57, 15 May 2016 (UTC)

Possibly not what you are asking, but my sister-in-law who is a nurse has told me that they can tell what the difference is between a Clostridium infection, C.diff and gastro-enteritis simply by the smell of the stools. The human nose is, as always, a far superior organ to any artificial nose. --TammyMoet (talk) 18:45, 15 May 2016 (UTC)

You can detect some diseases by analysing exhaled gases, which is close to the OP's question. [33]. LongHairedFop (talk) 21:03, 15 May 2016 (UTC)

Analyzing gases from breath and skin is well known and can be refined. Tuberculosis makes skin smells like bread, some myocardial infarctions make skin smell burned or like smoke. Some blood suggar problems make breath smell like aceton or paint thinner. --Hans Haase (有问题吗) 09:19, 16 May 2016 (UTC)

Animals have amazingly developed senses of smell. See [34] and Canine cancer detection. 5.150.93.133 (talk) 09:49, 16 May 2016 (UTC)

There was a larger studie on flatulence gas mixture analysis a read a few years ago (I thought about how the collection was done) and there a peolple with hydrogen as a main compound while others have methane as a main compound, most of it is carbon dioxide any way. But the studie did not mention the trace gases which could indicate the mixture of microorganisms in the digestive tract.--Stone (talk) 10:06, 16 May 2016 (UTC)

Flatus can be collected in a "flatal bag" and then analyzed, but this doesn't seem to happen much, presumably because there are more accurate ways to evaluate digestive system problems, such as a stool analysis, where the collection method is simpler. However, a sudden change in flatulence, without any obvious cause like a change in diet, might be reason to see a doctor. StuRat (talk) 16:08, 16 May 2016 (UTC)

its all about light

from where does the light gets its speed111111111us (talk) 18:19, 15 May 2016 (UTC)

The speed of light in a vacuum appears to be a universal physical constant of the universe. No practical answer to "why is it that way?" exists for such constants except for "because that's the way it is". — Lomn 18:46, 15 May 2016 (UTC)

Exactly. The speed at which light propagates can be decomposed into vacuum permittivity and vacuum permeability, which are fundamental constants that represent electric- and magnetic- components. Some physics books consider these properties to be even more fundamental constants than c (which can be derived from these other constants, based on our understanding of the way electric- and magnetic- fields interact). At the end of the day, they're still just constants that never seem to change, no matter how we measure them - and although we can study them from lots of perspectives, we don't actually have any specific explanation for why they take any particular value.

Nimur (talk) 20:42, 15 May 2016 (UTC)

The article Electromagnetic radiation also sheds some light on the subject. ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:53, 15 May 2016 (UTC)

Surprisingly, the answer to scientific questions is sometimes "philosophy or religion". The science don't know. (besides "whatever it is, the current speed of light will not be one of the values that makes your species impossible"). Sagittarian Milky Way (talk) 20:51, 15 May 2016 (UTC)

I agree it's philosophy but i'm not sure why anyone would call it "religion", it has very little in common with religion. In fact, one of the major philosophical shifts of the scientific revolution was to stop trying to explain the world with answers to "WHY?" questions, using agency and motivation to explain natural phenomena, and instead explain it with answers to "HOW?" questions using mathematics and models. In this case, it's not that "science doesn't know 'why' light travels that fast", it's because that question does not have a useful answer. Of course we can scientifically answer a "why" question like "why does a ball drop when you let it go", but you can't "why?" all the way down, the buck HAS to stop somewhere, and with science, the buck stops at the natural explanan it, because Gravity IS that way, or light IS that way. Religion would always take it one step further and say because god MADE it that way, but that extra step doesn't actually ADD any explanatory power so science dropped it. Vespine (talk) 01:18, 16 May 2016 (UTC)

See also Non-overlapping magisteria for one viewpoint on this. --Jayron32 02:04, 16 May 2016 (UTC)

It's only religion for some people. Sagittarian Milky Way (talk) 03:09, 16 May 2016 (UTC)

It depends on what "God" means. If you equate "God" to "Nature", then "God made it that way" is totally valid. But as you say, it doesn't really add any new information. ←Baseball Bugs ^{What's up, Doc?} carrots→ 09:40, 16 May 2016 (UTC)

It's rather nonintuitive, but light doesn't seem to accelerate or decelerate, it just always goes the same speed (in a given medium), similar to how electrons jump from one energy level to another, without seemingly ever having been in-between. The proverbial "quantum leap". StuRat (talk) 21:56, 15 May 2016 (UTC)

There is mention of nanoseconds there, isn't this rather slow in consideration with light ? So you say that the electrons jump ( in a few nanoseconds ), generating light in the process - which does not accelerate but is a full c speed right from the beginning. Is it that the famous quantum leap ? --Askedonty (talk) 11:17, 16 May 2016 (UTC)

Watch this video: [35] --71.110.8.102 (talk) 08:32, 16 May 2016 (UTC)

May 16

.1 (leading 0 is implicit)

Is .1 (leading 0 is implicit) always the same as 0.1? And even if mathematically they are the same, could a manual of style advise editors not to use the one or the other?--Llaanngg (talk) 01:37, 16 May 2016 (UTC)

yes and yes, seems obvious..is there a specific context for asking this?68.48.241.158 (talk) 01:44, 16 May 2016 (UTC)

It may not be the same if the "." in .1 is actually a blemish on the paper. Note that there could be infinite leading zeros, as there is no unit, no ten, no hundred etc.... Our style guide should have something to say on the matter. Graeme Bartlett (talk) 01:46, 16 May 2016 (UTC)

The style manual says to use the leading 0:Wikipedia:Manual of Style/Dates and numbers#Decimals. Graeme Bartlett (talk) 01:59, 16 May 2016 (UTC)

Indeed the mathematics and interpretation of .1 is the same as 0.1 - and style determines which to use. The leading '0' is a huge aid to readability - especially when you consider that there are parts of the world where the role of '.' and ',' are interchanged in their meaning within numbers. SteveBaker (talk) 02:17, 16 May 2016 (UTC)

I think Steve should have stopped before "especially". In areas where "," is the decimal point and "." is the thousands separator, neither ".123" nor "0.123" is a possible number; instead we would be talking about ",123" and "0,123", neither of which is a possible number where we live. --69.159.60.83 (talk) 05:51, 16 May 2016 (UTC)

The problem comes in when it is used cross-culturally. For example, if we wrote "Color was blue,and the quantity measured,123", that might be taken to mean 0.123 in a place where a decimal comma is used. Adding a space after each comma helps reduce this type of error. StuRat (talk) 16:30, 16 May 2016 (UTC)

Why is this question on the Science Desk? Joseph A. Spadaro (talk) 04:21, 16 May 2016 (UTC)

Species of deer fly

A deer fly with a centimeter scale

Can anyone identify the species of this deer fly (from near the Atlantic coast of Georgia)? Bubba73 ^{You talkin' to me?} 03:25, 16 May 2016 (UTC)

Not a very clear image - but it could be Chrysops vittatus (full description here - http://animaldiversity.org/accounts/Chrysops_vittatus/ ) 81.132.106.10 (talk) 20:44, 16 May 2016 (UTC)

It's a still dead no eyed deer fly. Vespine (talk) 06:28, 16 May 2016 (UTC)

Can a pregnant woman become pregnant again while still pregnant?

Can a pregnant woman become pregnant again while still pregnant? Just curious about that odd situation. If this were the case, the woman might give birth to a baby. And then, say, 4 months later, give birth to a second baby. Is this possible? Has this ever happened? Does this have a name? Thanks. Joseph A. Spadaro (talk) 04:23, 16 May 2016 (UTC)

Superfetation which has happened with human children conceived two months apart. This was very easy to find with google. μηδείς (talk) 04:59, 16 May 2016 (UTC)

It's possible, as noted, but very rare and abnormal in humans. Normally in humans, ovulation is suppressed during pregnancy by high levels of progesterone. Most hormonal contraceptives work the same way, by containing a progestin that has the same effects. --71.110.8.102 (talk) 06:30, 16 May 2016 (UTC)

It is worth noting that although there are a few recorded cases of a second conception (though only during the early stage of the first pregnancy - two months seems to be the longest recorded gap) the births in each case have been simultaneous. It seems extremely improbable that the first conceived child could be delivered, while the second one then continued to develop in the womb for a significant period. 81.132.106.10 (talk) 08:21, 16 May 2016 (UTC)

However, there are cases where twins are born some months apart because of danger to one of the babies. Do a Google search on "twins born some months apart" for examples. --TammyMoet (talk) 10:06, 16 May 2016 (UTC)

I believe these two cases can be reconciled by stating that it normally requires medical intervention to deliver only one of the babies without the other(s) being born soon after. A C-section, presumably, is the normal medical intervention. Not sure if this would be possible with identical twins, which share the same amniotic sac (could it be cauterized/sutured ?). StuRat (talk) 16:18, 16 May 2016 (UTC)

No, StuRat; monoamniotic twins are extremely rare. DMacks (talk) 16:37, 16 May 2016 (UTC)

Not that rare, "about 1% of twin pregnancies", according to our article. StuRat (talk) 17:17, 16 May 2016 (UTC)

No Stu. 0.00285714285714% to 0.0016666666666667% of pregnancies is extremely rare!--TMCk (talk) 17:41, 16 May 2016 (UTC)

I don't think it is. We wouldn't call a disease that was that common "extremely rare", as then up to 200,000 people worldwide would have it. But, again, you are taking the percentage of the entire population, while I was only talking about identical twins. StuRat (talk) 17:47, 16 May 2016 (UTC)

Sure. That's why you removed the inconvenient part of your post. Full of it as always.--TMCk (talk) 17:55, 16 May 2016 (UTC)

I didn't notice that they had stated the odds directly in the article the first time, and removed my math and replaced it with a direct quote as soon as I did. And keep the attitude off the Ref Desk, please. StuRat (talk) 22:52, 16 May 2016 (UTC)

While it isn't a "disease", the accepted medical definition of "rare" is covered at Rare disease, with definitions ranging from 1/1000 of 1/200,000 as being "rare". .002% is 1 out of 50,000 pregnancies. --Jayron32 17:57, 16 May 2016 (UTC)

Do they define "Extremely rare" ? StuRat (talk) 22:52, 16 May 2016 (UTC)

I actually believed something similar. But I also did what TammyMoet recommended. From there I read sources like [36] which suggest this can occur without apparent significant medical intervention medical intervention. In fact [37] suggests medical intervention in the opposite direction i.e. ensuring the second twin was delivered at the same time used to be more common.

Note also that the original discussion was about pregnancies with conception happening at different times. Monoamniotic twins are already rare enough. Monoamniotic non identical twins with conception happening at different times is probably as close to impossible as we get in biology.

Perhaps of more relevance to the original question is that in rare cases a women with double uterus have had successful pregnancies in both uterus simultaneously. StraighDope mention a few, another slightly more recent one is here [38]. Possibly conception happening at different times is more likely in these cases than in a more "normal" case although since there are so few of them, conceptions happening at different times would be more likely in more "normal" cases. (To be clear, I'm not saying conception at different times is likely if a woman has a double uterus, but rather the probability of it happening, low that it is, may be higher.)

Nil Einne (talk) 18:23, 16 May 2016 (UTC)

Would that be "double uteri" ? StuRat (talk) 22:56, 16 May 2016 (UTC)