Wikipedia:Reference desk/Archives/Miscellaneous/2011 September 9

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September 9

Mass of the Planet

Would the Mass of planet in the following equation be infinity / undefined when artificial satellite suddenly start hovering or stopped orbiting the planet i.e T = 0?

Mass of planet = M = [4/G*(pi)^2] * [(R^3)/(T^2)]68.147.41.231 (talk) 02:29, 9 September 2011 (UTC)Eccentric Khattak#1

The T in that formula is the time it takes the satellite to orbit around the planet. So yes, if the satellite goes around the planet in zero time, the planet would have to have infinite mass. Looie496 (talk) 06:06, 9 September 2011 (UTC)

I can just see the mathematical purists cringing at the notion of infinity being a number. The better way to express it would be that as T approaches 0, M approaches infinity (or vice versa). ←Baseball Bugs ^{What's up, Doc?} carrots→ 10:26, 9 September 2011 (UTC)

(ec) Neither of which has any meaning, either theoretical or real. Division by zero does not result in infinity; it is not defined at all. The best we can say is that the shorter the time the satellite takes, the greater the mass the planet has to have. But "infinite mass" is more than even the mass of the entire universe, a slightly impractical concept. -- Jack of Oz ^{[your turn]} 10:29, 9 September 2011 (UTC)

"Division by zero ... is not defined at all"? We have an article (of course) that suggests otherwise. In particular, in computer arithmetic, "The IEEE floating-point standard ... specifies that ... division by zero, has a well-defined result". Mitch Ames (talk) 14:27, 9 September 2011 (UTC)

That may be true in a virtual environment, but in reality, there is no defined result for a division by zero and no real infinity either. Those are simply tools that mathematicians and programmers use which have no natural examples. Googlemeister (talk) 20:30, 9 September 2011 (UTC)

Indeed. The existence of an encyclopedia article on something does not mean that that something exists. See Squaring the circle. See Utopia. See Flying pig. Division by zero is a comprehensive, some might say long-winded, exposition about how division by zero is not defined at all, as I said. -- Jack of Oz ^{[your turn]} 20:42, 9 September 2011 (UTC)

Division by zero isn't meaningless. 0/0 is indeterminate, which means that if you derive x = 0/0 it tells you nothing about x (the same as 0·x = 0). But x may still have a value, which you have to find in another way. 1/0 = ∞ is a well defined quantity in many contexts. All of this is covered in the division by zero article. The lede does mention that 1/0 has no value in real number arithmetic. But neither does ${\sqrt {-1}}$. -- BenRG (talk) 01:41, 10 September 2011 (UTC)

Thanks for showing me the big picture, Ben. I like big pictures. -- Jack of Oz ^{[your turn]} 20:27, 10 September 2011 (UTC)

One more similar question:

Here is the derivation of Mass of Earth.

http://www.enchantedlearning.com/subjects/astronomy/planets/earth/Mass.shtml

Isn't Mass of the Earth varies with increase in the size of resting mass [near the surface of earth] because of increase in the on-center distance between the two masses e.g moon on the earth.

Thus center to center distance between two masses = d = Radius of earth + Radius of moon. Therefore

Mass of Earth = M = [g x d^2]/G instead of M = g x R^2/G, where R = Radius of earth68.147.41.231 (talk) 18:56, 9 September 2011 (UTC)Eccentric Khattak#1

Barge wreck containing hogs on Withlacoochee river in Sumter County Florida approx 1922, Barge Manifest.

How may I find the manifest or any information of a barge that came apart after striking some rocks on the Withlacoochee River in Sumter County Florida approx 1922 allowing the hogs it was transporting to swim ashore on the Sumter County side of the river giving it the nickname Hog County? The barge is still there and can be seen during low water. I once read documents that a friend had researched that gave the specifics of this incident but he has since passed and his wife could not locate them. Thank you so much for allowing me to ask this question and I have my fingers crossed in hopes that you may be able to help me. — Preceding unsigned comment added by Jhschleman (talk • contribs) 04:18, 9 September 2011 (UTC)

Skyrim

Will you still be able to play as a female in skyrim? . — Preceding unsigned comment added by 94.197.113.195 (talk) 04:57, 9 September 2011 (UTC)

The Elder Scrolls V: Skyrim doesn't say you won't, and I'm pretty sure you could in the previous Elder Scrolls games. --Jayron32 05:05, 9 September 2011 (UTC)

Yes you will be able to play as a female. The Elder Scrolls official site already released many female race screenshots. Royor (talk) 06:27, 9 September 2011 (UTC)

Same thing invented or discovered independantly by two (or more?) people

A colleague of mine and myself were both given the same problem to work on by our boss. Without speaking to each other, we both came to the exact same conclusions. He cc'd me in his email, and I cc'd him, so we both saw what we'd come up with. We all had a bit of a laugh, and I got to thinking about Newton and Liebniz, who both (independantly) developed the calculus. Then I got to thinking about Bell and Elisha Gray, who both (independantly) developed the telephone. So I thought I'd ask the desk - are there any other famous cases of people (or teams of people) inventing or discovering the same thing, whilst working in isolation, only to be dismayed when they find out that they were "beaten to the punch" by the other party? — Preceding unsigned comment added by 121.44.191.154 (talk) 12:19, 9 September 2011 (UTC)

The dome seems to have been invented independently by folks in the middle east, and by Eskimos (in the form of igloos). HiLo48 (talk) 12:22, 9 September 2011 (UTC)

List of scientific priority disputes and Category:Discovery and invention controversies might be helpful here (though they don't all fit your specifications exactly). ---Sluzzelin talk 12:30, 9 September 2011 (UTC)

List of scientific priority disputes is pretty much what I was looking for. Thanks heaps!! 121.44.191.154 (talk) 13:36, 9 September 2011 (UTC)

Television - multiple parallel inventors; principle of natural selection - discovered independently by Charles Darwin and Alfred Russel Wallace. Gandalf61 (talk) 12:40, 9 September 2011 (UTC)

There are tons and tons of such instances. Rarely is any invention "out of the blue" to the degree that there weren't other people working very closely on the same topic. This is the case especially in science, where there aren't always priority disputes, but there are instances of people discovering something just days or weeks ahead of someone else doing so. If Hahn and Meitner had been distracted, nuclear fission would have been discovered by someone at UC Berkeley; if James Chadwick had taken the week off, the neutron would have been discovered by the Joliot-Curies. If Darwin had drowned in the Galapagos, the history of evolutionary science likely wouldn't have changed much. From an abstract point of view, this makes sense: it is very rare for someone to be so "out of their time" that they are not being influenced by the same problems of the day as their contemporaries, and while there have been a few singular geniuses, it is rare that they have existed in time periods where there weren't other similarly qualified geniuses also working on similar things (Newton and Leibniz being a great example of that).--Mr.98 (talk) 13:20, 9 September 2011 (UTC)

Technology and information build on previous technology and information, and are significantly driven by demand. The Connections TV series from the 70s/80s made this point repeatedly. Two obvious examples in recent history: the automobile, and the computer. ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:27, 9 September 2011 (UTC)

Additionally, we have a myth of the lone, genius inventor which presumes they just hang around until a light bulb goes off over their heads. In most cases this is false. Thomas Edison, the exemplar of the genre, actively promoted this sort of myth, even though in his own work, he relied heavily on basic research (done by people working under him, like Tesla), extensive patent libraries (so he could see what other people were working on, or where they had almost got things right, but not quite), and lots of grinding toil. This isn't to undermine Edison — he clearly was a master at this approach — but just to emphasize that there's no surprise that he and others like him often had very similar ideas. --Mr.98 (talk) 15:07, 9 September 2011 (UTC)

Even at that, Edison supposedly said that an invention is "10 percent inspiration and 90 percent perspiration." I happened to see a program the other day that pointed out that Edison wasn't the first to invent the light bulb, but rather the first to create a practical and affordable bulb. It also stated that he holds the record for quantity of patents: 1,300, or some such figure. But the real key was that he wasn't just focused on the light bulb, but on the entire process, including widespread electrical power to sell to the public. Where he messed up, though, is his tendency to stick with what he had worked with, i.e. direct current. Tesla was a promoter of alternating current, but he wasn't very good at self-promotion. Luckily, he found George Westinghouse. And I guess we've just raised another example of the OP's question: Two guys developing electrical systems at the same time. Tesla's system won, but Edison's name is on the power companies. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:44, 9 September 2011 (UTC)

In each case - Newton's observation about "standing on the shoulders of giants" remains true. Credit the man who invented the wheel with starting it all rolling. Collect (talk) 16:48, 9 September 2011 (UTC)

Please, I think you meant "Bernard of Chartres' observation". Deor (talk) 18:39, 9 September 2011 (UTC)

He was a plagiarist then - but he said it in English. <g>. Collect (talk) 23:05, 10 September 2011 (UTC)

A term describing this phenomenon, widely known in the Science Fiction community though probably not originating there, is "steam engine time." (I know the site of that link is not a reliable source, but in this instance it corresponds with my experience and saves me a lot of typing :-) ) {The poster formerly known as 87.81.230.195} 90.197.66.202 (talk) 18:33, 9 September 2011 (UTC)

Bernoulli number was discovered by Jakob Bernoulli in 1713 and Seki Takakazu in 1712. Determinant by Gottfried Leibniz and Seki Takakazu. See also List of multiple discoveries. Oda Mari (talk) 05:29, 10 September 2011 (UTC)

How do I define Operating Profit Per Share of a company?

Pleae let me know how does it help analysts to know how the company is performing. — Preceding unsigned comment added by Braychaudhuri (talk • contribs) 12:40, 9 September 2011 (UTC)

Profit = (income - expenses)/(number of shares). The special thing about "operating profit" is that the values you use for income and expenses only derive from ongoing operations, not from other ways a company can gain or lose money. A positive operating profit means that the company is fundamentally a viable business, even though it may temporarily be losing money for some reason; on the other hand, a negative operating profit means the company is not viable over the long term, even if it is temporarily making money. Looie496 (talk) 14:27, 9 September 2011 (UTC)

"How do I define Operating Profit Per Share of a company ?" - Operating Profit Per Share = operating profit / number of ordinary shares issued

"How does it help analysts know how the company is performing ?" - not much use on its own, but if you compare it with the market price of each share then you can calculate a P/E ratio that tells you whether a company's shares are under-priced or over-priced compared to its competitors. Gandalf61 (talk) 14:28, 9 September 2011 (UTC)

You could also compare the operating profit with the value of the company's assets to determine the Return on equity of the company, an important indicator of, indeed, how well the company is performing. Comet Tuttle (talk) 22:13, 9 September 2011 (UTC)

What problems would sociologists face when ...?

problems sociologists would face when applying the methods of the natural sciences to the study of society — Preceding unsigned comment added by 190.58.156.26 (talk) 14:21, 9 September 2011 (UTC)

Note: I have given this section a title. Looie496 (talk) 14:27, 9 September 2011 (UTC)

It is extremely difficult to isolate variables for societies as far as experimentation goes. Googlemeister (talk) 14:38, 9 September 2011 (UTC)

Yup. And there are ethical considerations too. Mostly, though, they'd have the problem of trying to figure out what 'methods of the natural sciences' would be even remotely relevant. AndyTheGrump (talk) 15:00, 9 September 2011 (UTC)

Presumably, the principal method of the natural sciences under consideration is the experiment. But even with observational studies, the presence of an observer can affect people's behaviour, which is different to what happens when you watch inanimate objects (inanimate objects may have observer effects, but don't deliberately act funny to annoy anthropologists). --Colapeninsula (talk) 15:09, 9 September 2011 (UTC)

Richard Feynman fulminates at length about the soft sciences in Surely You're Joking, Mr. Feynman!; well worth a read. --Tagishsimon (talk) 15:14, 9 September 2011 (UTC)

Actually, Feynman was a fine (though not formally trained) practitioner of social science methodology himself - see for instance his role in the enquiry of the causes of the Challenger disaster. AndyTheGrump (talk) 15:24, 9 September 2011 (UTC)

Yup, that too is a good read. Per Googlemeister, he's not at all happy that such people manage isolate variables, and compares the contemporary practise of the soft sciences as a Cargo cult - indeed, here are some of his thoughts as a PDF. His appendix to the Challenger report is here. --Tagishsimon (talk) 15:33, 9 September 2011 (UTC)

I don't see how Feynman's article can be interpreted as a comparison of 'soft science' to cargo cults - instead, he is comparing bad science to cargo cults - he gives examples from physics, not sociology. Incidentally, he is over-simplistic in his depiction of actual 'cargo cults' too. Not that this is unusual - our own article doesn't exactly cover the topic in any depth. AndyTheGrump (talk) 15:50, 9 September 2011 (UTC)

It's my recollection that he does make the direct comparison within Surely you're joking.... But I don't have that to hand right now. --Tagishsimon (talk) 15:55, 9 September 2011 (UTC)

I do remember him poking fun at a sociologist's "Academese" in SYJMF. He translates "The individual member of the social community often receives his information via visual, symbolic channels." to "People read.". See here, for example. ---Sluzzelin talk 16:25, 9 September 2011 (UTC)

The chief problem here (in my opinion, a flaw in the whole project very idea of the social "sciences") is that the scientific method of isolating and testing variables and establishing mathematical relationships of correlation works very well as a way to gain understanding of mechanistic and automatic natural processes. However, these methods fail to have the same explanatory power when dealing with human actions, which are seldom mechanistic or automatic. Instead, human actions are mediated by the highly dynamic processes of psychology and culture, each of which itself involves a myriad of interacting variables at the level of the chemistry of individual neurons. In the case of culture, these neurons can belong to millions of individuals acting with some degree of autonomy. As a result, applying the methods of natural science to human problems involves putting on blinders to the intricacy and dynamism of psychology and culture. The adoption of these methods was an essentially political project conceived during the ascendancy of natural science from the late 19th to the mid-20th century in an effort to claim for the social sciences the same efficacy and prestige that the natural sciences enjoyed. The use of reductive and quantitative methods in the social sciences has produced results that are generally inferior in explanatory power to the use of more humanistic methods that can account for the dynamic forces of psychology and culture. Marco polo (talk) 15:39, 9 September 2011 (UTC)

If 'the whole project of the social sciences' worked upon principles of 'isolating and testing variables' in this simplistic manner your comments might be valid. They don't, so they aren't. In fact, the whole debate is a bit of a red herring. Trying to determine whether say social anthropology belongs in the social sciences, or in the humanities, tells us next-to-nothing about what it is - and the best definition of anthropology I've seen is that it is 'what anthropologists do'. Feynman's work on the challenger enquiry was closer to anthropology than to physics, and was more fruitful as a result. AndyTheGrump (talk) 16:08, 9 September 2011 (UTC)

Andy's criticism is entirely correct. I was sloppy in my language and have edited it accordingly. I didn't mean to condemn all of the activities labeled "social sciences", just those that attempt to apply the methods of the natural sciences to the realms of culture and human interaction. However, I think that the very term social science and the idea embodied in that term is an unfortunate example of the effort to apply the methods of natural science to the realms of society and culture and a continuing source of justification for academics in the "social sciences" to attempt to apply such methods. Incidentally, social or cultural anthropology is probably the discipline least guilty of "scientific" reduction and statistical nonsense. Anyway, the question was about sociology, and I was thinking mainly of sociology in writing my response. Marco polo (talk) 18:31, 9 September 2011 (UTC)

Andrew Sayer, Method in the Social Sciences may be of use here. Itsmejudith (talk) 19:08, 9 September 2011 (UTC)

There's a misconception that if it can't be captured in an equation, it isn't knowledge. There's lots of valid insight and learning and novel ideas that are developed through the social sciences. --Jayron32 02:42, 10 September 2011 (UTC)

Knowledge creation

About 1000 new articles are created per day. Is notable knowledge created faster in the real world? Is knowledge creation expected to decrease in the next decades or centuries or to accelerate? emijrp (talk) 20:45, 9 September 2011 (UTC)

Our article accelerating change is relevant. Comet Tuttle (talk) 22:10, 9 September 2011 (UTC)

It's a good example of the difference between "notability" and "knowledge", but other than that no. Rapid progress doesn't continue forever. It continues for a while, then slows down again. In the early days of the space program people thought we'd be mining asteroids by now. In the early days of AI research people thought we'd have Lt. Cmdr. Data by now. In every era of human history there are people who think the End Times are nigh. Just ignore them. -- BenRG (talk) 02:11, 10 September 2011 (UTC)

Thing is, there's abstraction. If knowledge creation resembles data compression, eventually the trend may be for a reduction in the number of articles, the reduction accelerating in step with the rate of knowledge creation. The criteria for notability in Wikipedia would have to evolve to exclude old facts as they lose importance. If the criteria remain the same, unimportant old facts will continue to pass the notability test, meaning that Wikipedia doesn't just record knowledge, but data too.  Card Zero  (talk) 00:47, 10 September 2011 (UTC)

Note that notable knowledge 'creation' doesn't have to result in the creation of a new article, but could simply result in changes to one or several old ones. Nil Einne (talk) 23:51, 10 September 2011 (UTC)

A study shows how unique red links increase over time. emijrp (talk) 21:08, 10 September 2011 (UTC)

In theory, wikipedia doesn't "create" knowledge at all, it merely summarizes it from valid sources. ←Baseball Bugs ^{What's up, Doc?} carrots→ 14:02, 11 September 2011 (UTC)

It's not just a theory - WP:No original research is one of the core content policies. Mitch Ames (talk) 12:49, 13 September 2011 (UTC)