Talk:Pi

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April 18, 2012Peer reviewReviewed
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Integral definition of pi[edit]

Why starting with the strange formula

instead of a natural one

? — Preceding unsigned comment added by 193.48.71.230 (talk) 13:28, 4 October 2018 (UTC)

Straight from the article (refs removed):

Here, the circumference of a circle is the arc length around the perimeter of the circle, a quantity which can be formally defined independently of geometry using limits, a concept in calculus. For example, one may compute directly the arc length of the top half of the unit circle given in Cartesian coordinates by x2 + y2 = 1, as the integral:

So if one thinks of π as the ratio of the circumference to the diameter, that's the integral that pops out. –Deacon Vorbis (carbon • videos) 13:43, 4 October 2018 (UTC)

Semi-protected edit request on 11 October 2018[edit]

The pronunciation at the top is wrong. The /p/ in the word pi is aspirated, so it should be /pʰaɪ/, not /paɪ/. Nvidovic (talk) 22:14, 11 October 2018 (UTC)

Not done. I'm not an expert on IPA stuff, but as far as I can tell (such as at Help:IPA/English, the aspiration mark isn't used, as any p in English is more or less the same. –Deacon Vorbis (carbon • videos) 23:26, 11 October 2018 (UTC)
Afaik, the "p" in the relevant phonem is always considered to have an aspirated "p". However, I do not know whether linguists unanimously agree on the existence of aspirated plosives, and I am ignorant about the pertinent WP-rules, probably claiming what non est in actis non est in mundo. May an expert in both take care of this? Purgy (talk) 05:39, 12 October 2018 (UTC)
Countenance, Sir, countenance ... I'm terribly sorry for having missed you, Sir, being such an expert, Sir! Purgy (talk) 12:56, 12 October 2018 (UTC)
English does not use aspiration to distinguish between consonants like /p/ and /b/, it uses voicing. /p/ is aspirated, though not as much as languages which use aspiration as the main way of distinguishing between such pairs of consonants. Chinese for example.--JohnBlackburnewordsdeeds 13:13, 12 October 2018 (UTC)

The answer, in broad strokes, is that WP uses a "phonemic" rather than "phonetic" transcription for English. Sometimes unfortunately, it uses a notional "phonetic" transcription for other languages, which leads to some renderings, like changing n to m before consonants in Italian, that give an entirely misleading impression, but that's not important right now. At the phonemic level, there is no need to mark aspiration, at least not in English. --Trovatore (talk) 02:15, 13 October 2018 (UTC)

Semi-protected edit request on 18 October 2018[edit]

Please update the approximate value of PI from 3.1415 to ACTUAL VALUE of (9sqrt2)/4 based on S^2=4Ci. This value is derived by squaring 4 circles, not one, as can be demonstrated in the link from Numberphile. Please remember this is 1:4 not 1:1, as 1:1(squaring a single circle) has NEVER worked to give the actual value. Before you throw off the idea, the question must be asked, "What prevents the approximate value, when increasing accuracy, be bound to the thousandths place and exclude the hundreths onward."


Explanation of why it is 1:4 not 1:1: Unexpected Shapes (Part 1) - Numberphile

Proof: Unequivocally Expressing PI as a Fraction

Actual value: sqrt(9^2+9^2)-4((9sqrt2)/4)

Approximate value: sqrt(9^2+9^2)-4pi

Thank you for taking the time to verify each link as this is a groundbreaking discovery. Perpetualinput (talk) 03:58, 18 October 2018 (UTC)

Not done π is a transcendental number, but the expression you give is an algebraic number, and therefore cannot equal π. Also, you would need to provide a reliable source. --Trovatore (talk) 04:10, 18 October 2018 (UTC)
(edit conflict) Not done @Perpetualinput: Please take your pseudomathematics elsewhere. The Numberphile video does not at all claim to be squaring the circle (or even "four circles"). Plus, you seem incapable of the most basic arithmetic: . I will not waste my precious studying time explaining to you the blatant inaccuracies in your so-called "publication".--Jasper Deng (talk) 04:12, 18 October 2018 (UTC)

Semi-protected edit request on 18 October 2018[edit]

This edit request has been answered. Set the Perpetualinput (talk) 04:24, 18 October 2018 (UTC)

@Perpetualinput: You can consider your edit requests to insert your so-called "value of π" to be categorically and automatically declined, please do not waste any more of our time.--Jasper Deng (talk) 04:27, 18 October 2018 (UTC)

Semi-protected edit request on 15 November 2018[edit]

How Pi might have come about? Humans might have wanted to know about the direct path to a point on earth exactly opposite to where they are. To find out, once it is known Earth is a sphere, they would have measured a cylindrical object's length of the circumference and the diamter. Using these measurements, they would have calculated the ratio and used it to derive the diameter of the earth by the known distance between the points. Thus, the Pi (22/7) might have come about. Wearewithyou (talk) 02:48, 15 November 2018 (UTC)

Not done. Edit request templates are not for making wild speculations. –Deacon Vorbis (carbon • videos) 02:58, 15 November 2018 (UTC)