Talk:Phi/Archive 1

Archive 1

More about Phi

In the book, The Hobbit, it talks about all this crazy stuff regarding Phi, and how it's a building block for life or something. Like if you measure your height from the tip of your head to the ground, and your waist to the ground, the ratio is equall to Phi. And the same goes for your fingers, arms, and alot of stuff in nature. Is this true? —Preceding unsigned comment added by 24.109.177.107 (talk • contribs) 21:15, 27 May 2006

Somewhat true, mostly exaggerated. See Golden ratio. —Tamfang 18:35, 28 May 2006 (UTC)

The empty set symbol

The letters Φ (obtained by typing &Phi;), φ (&phi;) or ${}{}\phi$ (<math>\phi<<\math>) are not the symbol for the empty set in mathematics, and should not be used as such in Wikipedia.

In Unicode, the empty set symbol ∅ (&#8709;) occupies code point U+2205. But many fonts in use today don't include this character and render it as a small rectangle.

The TeX symbol $\emptyset$ (<math>\emptyset</math>) looks funny and seems to dance above the baseline.

Therefore, I recommend using either Ø (&Oslash;) or {} ({}) to indicate the empty set.

—Herbee

Similarly, there's a Unicode diameter symbol, ⌀ (&#x2300;) which should probably be used instead of or in addition to the image being used on the page; I don’t know how widely-supported the symbol is. -Ahruman 07:36, 18 October 2006 (UTC)

History???

Where did Φ originate from (symbolically)? Tdinatale (talk) 17:04, 10 August 2009 (UTC)

Transliteration

Does anyone have any idea why it's transliterated into the modern Latin alphabet as "ph"? It's always seemed odd to me, even more odd than other two-letter combinations that make separate sounds, like "sh" and "th" -- in those cases, the mouth/lips/tongue are at least in a similar position to the normal pronunciation of the letters preceding the "h". And especially because we have a letter for this. It's called F. Is there any particular reason why these words/roots are not spelled like "filosofy" and "fobia", or was it just a fluke of language development that became tradition?

Don't know, but if it's a comfort to you, english and french are about the only two languages that do it. There was a lot of treating labiodentals as labials, see Tengwar.

Lee S. Svoboda 22:31, 1 Apr 2005 (UTC)

I don't really KNOW, but the following, cut-and-pasted from H2G2 [1], seems relevant:

The Early Roman Alphabet

The Latins adopted writing from both the Etruscans and the Western Greeks in about the 5th Century. They had no use for the Z, Θ, Φ and Ψ characters of the Western Greek alphabet, so they dropped them from their alphabet.

The Romans needed a letter to represent the f sound in their language. The Etruscan language didn't have an f sound , and neither did Western Greek. (The Greek Φ was at that time pronounced ph, that is, a p with an h sound after it). They adapted the Etruscan letter F which was pronounced 'w' and gave it the sound 'f'.

They adopted an Etruscan three-lined zig-zag S and then curved it to make the modern curvy S. They used the Gamma < to represent both the Etruscan K sound and the Greek G sound. The early Roman alphabet looked like this:

A B C D E F H I K L M N O P Q R S T V X

There are a few differences from the modern alphabet:

C represented both the hard 'k' sound in 'cat' and the 'g' sound in 'garden'.

I represented both the vowel we call 'i' and the 'y' sound that we get at the start of the word 'yellow'.

V represented both the U sound of 'put' and a consonantal sound which was somewhere between our 'v' and 'w'.

[...]

The Eastern Greek Influence

In the 3rd Century BC, the Greeks led by Alexander the Great conquered all of the Eastern Mediterranean and east as far as India. Over the next few centuries, knowledge also spread out from Greece in all directions and the Romans absorbed a lot of ideas from Greek culture. Greek words started to be used in Latin. There was a need to be able to write down these words. The Romans transliterated most of the letters, making do with such combinations as PH instead of Φ and TH instead of Θ.

But they had no way of writing two particular Greek sounds, so in about 100 AD, the Romans borrowed two letters from the Eastern Greek alphabet. One was Y, which was very much the same as the V they had already got from Western Greek. In Eastern Greek it had retained a long stem while in Western Greek it had lost it. The Eastern Greek pronunciation was by now slightly different as well. It is the slender U sound we get in the German word 'fünf' or the French 'tu'. The other letter the Romans borrowed was the Zeta Z for the z sound. Both the Y and the Z were only used for writing Greek words so the letters were placed at the end of the alphabet, although Z had centuries before been positioned after F.

So by the time the Roman Empire reached its peak, the alphabet looked like this:

A B C D E F G H I K L M N O P Q R S T V X Y Z

Due to the Roman dominance of Europe, the Roman alphabet became the standard alphabet throughout Western Europe, and eventually was spread throughout the Western World.

--Niels Ø 09:57, Apr 2, 2005 (UTC)

The Greek phonemes ph, th, kh were originally aspirated stops (as in Hindi) not fricatives. It may well be that they had not yet become fricatives when Latin started borrowing words from Greek. —Tamfang 23:20, 25 February 2006 (UTC)

But how did the sounds change to fricatives?? Georgia guy 00:11, 15 March 2006 (UTC)

Perhaps there was an intermediate affricate stage, i.e. the aspiration became a homorganic fricative and then the stop dropped: ph → pf → f. (I am not a linguist but I play one on television.) You think that's curious, look up Grimm's Law. —Tamfang 05:47, 22 March 2006 (UTC)

I know this is late and many people may not like this answer at all but here is what really happened (and it isn't so exciting really).

The Egyptians had the glyphs (picture writting) that poor people turned into just symbols representing sounds. Of the original glyphs there were about 6000. 200 of those became the letters used by the common people. Then the Hebrew people had contact with Egypt and adopted 22 of those letters to write their language. The shape of the letters got gradually simpler with each new group that adopted it. Each letter in fact stood for several different sounds and spelling was far from standardized. Also, the letters only stood for consonant sounds, with the unseen vowel sounds just being supplied by the reader. This is in part what allows semitic pepoles today to have the exact same writting system, same cosonants in a word but pronounce it differently from area to area.

The magic moment that separates the Consonant only kind of writting from the Alphabetic writting with shown vowel sounds happened in Greece.

Now I know some people are going to disagree with what I am about to write but all the evidence I have seen in ancient text informs me of the truth of it.

When the Greeks borrowed the Hebrew (phonoecian) alphabet they took six of the letters and made them into vowel sounds. Two of these letters represented sounds that just did not exist in Greek at all. The others were only seldomly used.

Now I won't get into what each letter became so I will focus on Φ.

The letter that Phei was created from was a semitic letter that looked like a staff with an almost closed circle at the top. This letter in the Semetic languages represented W, Wh, V, Vr, F, Fr, OO (u), and the U sound in the word UP. How it was pronounced depended on who was saying it and which semetic language they spoke. It was also written slightly differently from tribe to tribe. The Greeks took the letter and Adapted it. They broke it into three letters. The first was of course Upsilon, with is a stick with a rounded top but the two sides were widened into a bowl. The second was Phei, which originally looked like a stick with the circle on the top, but as writters used the letter they began to write the circle part first instead of second and this had the effect of increasing the size of the circle and the stick became a line that went through the center (similar to qoppa). As Qoppa had follen out of use rather fast, this produced no problem. The third letter was Digamma, which just put the opening to the side instead of the top and squared it off. Upsilon was the V sound, Phei was the F sound and Digamma was the W sound. Upsilon also did duty as the OO sound. It later changed to a Yoo sound and then finally it was completely ionified and now sounds like EE.

The reason Phei gets transliterated into Latin as PH is due to the fact that the Latin F was harder than the Greek PH. In Latin the F sound is made by touching the lower lip to the top teeth. In Greek this sound was made by lightly separating the lips and making a HOO sound. Also, in ancient times, Latins and Greeks actually thought they used the same alphabet and were happy to transliterate words and sounds but since the shape of the letters they used for this sound differed, they wanted to use something else so that they would know from which Greek letter it came from so that if need be, they could transliterate it back into Greek.

The Romans were exposed to the writting of the world from several sources, the punics, Etruscans and the Greeks. It isn't like they sent a manned expidition to Greece to learn writting. These letters were out there in the market place and the Romans just picked them up. They borrowed Y and turned the shape of it into V and it stood for the V sound (a voiced F sound produced by touching the bottom lip to the top teeth). It also stood for the OO sound. If they Romans encountered people who had the W sound they used the OO sound to aproximate it but the Romans themselves did not have this sound in their native language. So a person named Walter would have a Roman trying to say his name and hearing OO-al-ta-r. The claudian digamma was breifly used for the W sound in Latin but since it was only needed for foriegn words it was never fully adopted to write native words in Latin.

So there you have it. Phei equals F and both dirive from the same source letter in Semitic but for historical and cultural reason are maintained as seperate letters. —Preceding unsigned comment added by 219.127.251.137 (talk) 05:34, 1 October 2008 (UTC)

Variants

Why are there two versions of the lowercase phi? --Abdull 13:26, 15 June 2006 (UTC)

For much the same reason as two versions of lowercase 'a'. —Tamfang 03:07, 16 June 2006 (UTC)

Interestingly, the different versions of phi have their own code points in character sets such as Unicode while there exists only one code point for the lowercase 'a', despite different versions. So there aren't moments when it is more appropiate to use one version of the lowercase phi instead of the other? --Abdull 16:57, 19 June 2006 (UTC)

From the way they're written, it looks like the swirly one is more for handwriting and the other one is for printing. Just a guess. Also, I think there is a code point for the a that looks like o|, buried deep in Unicode. 218.102.71.167 12:57, 20 June 2006 (UTC)

Yes, the two forms of 'a' are distinguished in the International Phonetic Alphabet, the simpler form being more "back" than the other. —Tamfang 02:17, 21 June 2006 (UTC)

The lede here tries to display the letter phi in four different ways; unfortunately, all of them display on my browser (Firefox on Ubuntu Edgy, using Bitstream Vera Serif) as the cursive variant. Part of this is due to this bug in MediaWiki's handling of maths markup. I've corrected one use of the unicode character which assumes the straight glyph where we can't guarantee that, but unfortunately this bug means it still looks the same. Hairy Dude 02:37, 16 December 2006 (UTC)

Update: Setting "Always render PNG" in your maths preferences makes it look right. Hairy Dude 20:20, 20 December 2006 (UTC)

The use of so-called variants confuses me too. As noted by Hairy Dude above, rendering in readers' browsers may not be what the article contributors expect. For example, the sentence "The lower-case letter φ (or often its variant, \varphi)" renders basically the same glyph twice with my settings — once as a Unicode character, and once as an image (not shown here). In both cases the glyph appears as an incomplete circle with downstroke. The problem is that U+03C6 renders in this way in some fonts (e.g. Times New Roman, Arial), but as a complete circle with slash in other fonts (e.g. Palatino Linotype). Just to confuse things still further, at the article's mention of U+03D5 (sometimes) the character is rendered as what I can best describe as rho (ρ) mirrored on its downstroke. ("Sometimes", because as I flip between tabs and adjust the font size in my browser, the glyph keeps on changeing between this and the incomplete circle with downstroke! Perhaps a realisation of the bug referred to above??)

Beyond this, the Unicode Code Chart shows U+03C6 as incomplete circle with downstroke, and U+03D5 as complete circle with slash. ...although this should be read with the disclaimer "[...] the charts do not specify the exact shape; they only provide a representative shape for identification." [2]

By the way, Hairy Dude, I'm also using Firefox (v1.5.0.10), and can't figure out where the "Always render PNG" setting is that you mentioned.

— DIV (128.250.204.118 07:13, 5 March 2007 (UTC))

*Answering own question*

I've now found the "Always render PNG" option at Help:Preferences#Rendering_math, but it only works for people who log in ...to view the page! (At least, as far as I can see.) So fairly useless, I would have thought, for the majority of article readers.

— DIV (128.250.204.118 05:49, 18 March 2007 (UTC))

*Answering own question* (again)

Refer to WP:FORMULA#Forced_PNG_rendering

—DIV (128.250.204.118 07:50, 14 April 2007 (UTC))

Reversed

As noted above Palatino Linotype reverses the glyphs for phi and phi symbol. That is, the 'letter' U+03C6 renders as $\phi \,\!$, while the 'symbol' U+03D5 renders as $\varphi \,\!$. Here is another example, DatapageMath4 from Mathtype. —DIV (128.250.80.15 (talk) 07:48, 4 February 2009 (UTC))

Lucida Sans Unicode also more-or-less reverses the glyphs. The 'letter' U+03C6 renders as $\phi \,\!$, whereas the 'symbol' U+03D5 renders as the 'mirrored-rho' described above, which looks something like $\mathrm {\varphi } \,\!$, but with the left-hand curve joined to the top of the stem. Cyrillic 'ф' is rendered in a similar fashion, except that for U+03D5 the stem has no ascender, and the curve from left to right is smooth at the bottom. [ф in turn appears like a mirrored version of thorn, þ.] (Evidently the reason the mirrored-rho variant glyph sometimes appeared on my system was that my default font in some applciations is Verdana, which doesn't support the character U+03D5.) —DIV (128.250.247.158 (talk) 07:19, 2 March 2009 (UTC))

Nullity

http://www.bbc.co.uk/berkshire/content/articles/2006/12/06/divide_zero_feature.shtml Ben 20:38, 7 December 2006 (UTC)

Ph and f

Why does this article neglect that ph and f aren't the same letter? (in latin and greek at least ph is softer) 82.18.172.41 12:24, 15 December 2006 (UTC)

Co-ordinates

A third spherical co-ordinate system convention is to measure positive φ up from the x-y plane to the z-axis. (Third in the sense of besides the two currently listed, not in the sense of third-best!) Don't know what fancy name to call this, but it could/should be added to the article to avoid bias. — DIV (128.250.204.118 07:23, 5 March 2007 (UTC))

"Variant" glyph?

The sentence,

"The lower-case letter $\varphi \,$ (or often its variant, $\phi \,$) is often used..."

seems to imply that "varphi" refers to the standard glyph, while phi refers to the variant form!

This seems wrong, though I assume it was intentional. Why is it like this? —Preceding unsigned comment added by Dratman (talk • contribs) 13:47, 13 November 2009 (UTC)

Just a suspicion which I doubt I'll be able to confirm, but it's likely that varphi is the actual Greek letter, while phi is a bastardization of ease. --Izno (talk) 14:53, 13 November 2009 (UTC)

It's not. $\phi \,$ is the correct form. I'm pretty sure that $\varphi \,$ is ypsilon. But I know $\phi \,$ is right. --N3g4t1v3z3r0 (talk) 23:37, 14 December 2009 (UTC)

Um, no. Greek ypsilon is υ ($\upsilon \,$) in lowercase, Υ ($\Upsilon \,$) in uppercase. Both the $\varphi \,$ and $\phi \,$ glyphs are variants of lowercase phi.—Emil J. 16:45, 2 April 2010 (UTC)

Usage

Is not the uppercase Phi a symbol for physics wheres Psi is the symbol for philosophy? Greetings, PassPort --87.144.71.113 (talk) 14:52, 22 January 2011 (UTC)

Phi in First-order Logic

This Wikipedia entry http://en.wikipedia.org/wiki/Predicate_calculus shows Phi being used to represent a sentance. I was just reading about it, so someone more knowledgable should fix the entry. — Preceding unsigned comment added by 69.180.204.245 (talk) 17:25, 29 July 2011 (UTC)

Pronunciation

The article says it's pronouced fee, but every lecturer and school teacher I've ever had (in Physics, Maths and Computer Science) has pronounced it fie. Does anyone know why this is? Is it an English vs. Greek vs. American difference in pronunciation? -- Karl Naylor 14:35, 23 May 2004 (UTC)

I have researched this pronunciation over the last several weeks pretty extensively (because somehow I have an itch that just must be scratched). The references I have found are distributed fairly evenly across three groups: 'fee', 'fie', and 'both'. Generally, those references that claim authority in a scientific or mathematical context generally claim 'fee'. Those references that are authoritative in Greek language studies claim either 'fie' or 'both'. In my college experience (math, physics, computer science), most instructors or professors used 'fee'. However, and curiously, many times the same instructors would pronounce the names of certain Greek association houses as 'fie', as in Phi Beta Kappa. Personally, I prefer 'fie' although in any case, I think the article should mention both pronunciations as being acceptable, depending upon context. -- Jim Richins, 29 June 2004

Everyone I know says fee, except my older brother who says fie, but hes a loser, so dont mind him. Fie as in pi & chi &c., but fee to be cool and know what you're talking about. daesotho 20:25, 15 Sep 2004 (UTC)

"Fee" is the actual Greek pronunciation (written φι, I believe). I've heard it pronounced both ways, but probably more commonly as "fee" in an academic setting. For what it's worth, the American Heritage Dictionary gives both pronunciations. Merriam-Webster gives only "fye". Personally, I say "fee", but to each one's own. Caesura 02:42, 19 Mar 2005 (UTC)

"Fie" is more common in .uk/.au/.nz English (in particular in mathematics, engineering and science done there). Don't remember what they say in .ca. Actually going by national stereotypes, koowoos would pronounce it "Foo" and Canadians "Feh?", but that's another story. Andrew Kepert 05:53, 21 Mar 2005 (UTC)

Anyone who doesn't know where 'fie' comes from should read about the Great Vowel Shift. ፈቃደ (ውይይት) 17:04, 14 March 2006 (UTC)

Maybe the source of confusion is that a word spelled "fie" or "fye" or "f'eye" (or whatever else) could be pronounced in a number of ways. Using IPA might clear things up a bit.

This dispute can be settled by noting the visual similarity between phi and theta; as the former resembles the latter turned sideways, it's known to some students as "gangsta theta". —Preceding unsigned comment added by 74.95.38.204 (talk) 03:52, 16 November 2009 (UTC)

I generally associate the "fie" people with mathematics and comp. sci., while "fee" with classicists. As a person who did a significant amount of stradling between those two worlds, I actually pronounce them differently depending on whether I am reciting the alphabet (fee), or reading about the golden ratio (fie). I also pronounce ξ, ψ, χ and π as "ksee", "psee", "khee" and "pee". VI_WS ^talk 03:39, 28 July 2011 (UTC)

Orphan question

i Have a question what are the unusual relationships to moderm times? — Preceding unsigned comment added by Kimon (talk • contribs) 17:26, 29 July 2011 (UTC)

phi in parallel computing

In parallel computing, phi is sometimes used to represent the fraction of time a computer program runs in parallel. — Preceding unsigned comment added by 81.33.111.249 (talk) 19:43, 18 March 2012 (UTC)

Edit request on 3 April 2012

The article states that phi is used to denote electric potential. Electric potential is measured in Volts and is denoted by a V. "Φ" is used to measure electric flux, not electric potential. Electric flux is the result of the change in an electric field through a given area. Specifically, Electric flux is equal to the integral of the Electric field with respect to differential units of area. In other words: Φ=∫E·dA. This is general knowledge within the field of Physics, and is even found on the Wikipedia page on electric flux. Please change "electric potential" to "electric flux." Thank you.

199.8.13.16 (talk) 20:08, 3 April 2012 (UTC)

Sure. --Izno (talk) 20:28, 3 April 2012 (UTC)

Phi is used for flux, but it is also commonly used to represent potential. — Preceding unsigned comment added by 139.80.236.34 (talk) 06:08, 8 August 2012 (UTC)

Source Request

Since when does phi represent 500 in the Greek numeric system? I was given to understand that Greek numerals were on base 24, with phi representing 22/24 just as 8 represents 8/10 in our base 10 system. Regrettably, I don't have a good source and so am wondering if there can be consensus that either a source should be provided for the "500" statement or we can remove it. Thoughts? 131.252.4.4 (talk) 18:53, 25 May 2012 (UTC)

You are misinformed, Greek numerals operate on a base 10 system. There are 24 letters in the Greek alphabet, but they have never used a base-24 counting system. Wikipedia has a good and accurate article on Greek numerals if you'd like to learn more. --145.226.30.45 (talk) 10:30, 26 November 2012 (UTC)

Semi-protected?

This article was semi-protected in 2010 for "ongoing high risk of vandalism". Nothing was added to the talk page by the person in charge of semi-protecting the article, and no actions of vandalism can [ttbomk] be found in the article history. I would like to revoke the protection of this article. Rgiusti (talk) 11:45, 29 January 2013 (UTC)

There are several cases of vandalism on this page. For example, [3], [4], and [5].--94knux (talk) 23:42, 11 February 2013 (UTC)

LaTeX representation

The article states, that the TeX representation of

• φ is \phi
• ϕ is \varphi

whereas Help:Displaying a formula - Wikipedia, the free encyclopedia, Hilfe:TeX – Wikipedia, LaTeX-Kompendium: Sonderzeichen – Wikibooks, Sammlung freier Lehr-, Sach- und Fachbücher,[6] states it should be the other way round

• φ is \varphi
• ϕ is \phi

Doing some research refering to LaTex-editors and generators I've found many systems, that use this literals differently. Is this not well defined? Voeren (talk) 08:37, 13 February 2013 (UTC)

In TeX, \phi is the stroked form of the character, and \varphi the loop form. In contrast, as you could read in this article if someone didn’t rather unhelpfully delete the explanation a month ago (the original version: [7]), there is variation among fonts as to which form the Unicode characters φ and ϕ have. Thus, claiming any 1–1 correspondence between the Unicode characters and TeX symbols is simply wrong, nevertheless the intention (not always followed) of the Unicode standard is that ϕ (U+03D5 GREEK PHI SYMBOL) should always have the stroke form, and as such corresponds to \phi, contrary to what our article states. Whether φ corresponds to \phi or \varphi is font-dependent.—Emil J. 13:17, 13 February 2013 (UTC)

I have restored the original information, and reformatted the rest without so much redundant detail.—Emil J. 14:01, 13 February 2013 (UTC)

Thank you EmilJ, that made it a lot more understandable. But shouldn't we make it even clearer by stating that the current Unicode chart clearly defines the loopy form on 03C6? Maybe in the column "Correct appearance"

Character	Name	Correct appearance	Your browser	Usage
U+03C6	GREEK SMALL LETTER PHI	( prior to Unicode 3.0)	φ	used in Greek texts
U+03D5	GREEK PHI SYMBOL	( prior to Unicode 3.0)	ϕ	used in mathematical and technical contexts

Voeren (talk) 13:32, 18 February 2013 (UTC)

No, it does not, that’s the point. Both forms are fine for 03C6, in accordance with Greek typography. The sample glyphs in the Unicode tables are not a normative part of the standard.—Emil J. 14:06, 18 February 2013 (UTC)

Ok, now I see this as well. But so I have another proposal to communicate this fact clearer, integrating a quote from the referenced unicode document. I've directly changed it in the document Voeren (talk) 16:10, 18 February 2013 (UTC)

Phi

Okay, how far should this go out: 1.6180339887 4989484820 4586834365 6381177203 0917980576 2862135448 6227052604 6281890244 9707207204 1893911374 8475408807 5386891752 1266338622 2353693179 3180060766 7263544333 8908659593 9582905638 3226613199 2829026788 0675208766 8925017116 9620703222 1043216269 5486262963 1361443814 9758701220 3408058879 5445474924 6185695364 8644492410 4432077134 4947049565 8467885098 7433944221 2544877066 4780915884 6074998871 2400765217 0575179788 3416625624 9407589069 7040002812 1042762177 1117778053 1531714101 1704666599 1466979873 1761356006 7087480710 1317952368 9427521948 4353056783 0022878569 9782977834 7845878228 9110976250 0302696156 1700250464 3382437764 8610283831 2683303724 2926752631 1653392473 1671112115 8818638513 3162038400 5222165791 2866752946 5490681131 7159934323 5973494985 0904094762 1322298101 7261070596 1164562990 9816290555 2085247903 5240602017 2799747175 3427775927 7862561943 2082750513 1218156285 5122248093 9471234145 1702237358 0577278616 0086883829 5230459264 7878017889 9219902707 7690389532 1968198615 1437803149 9741106926 0886742962 2675756052 3172777520 3536139362 1076738937 6455606060 5921658946 6759551900 4005559089 5022953094 2312482355 2122124154 4400647034 0565734797 6639723949 4994658457 8873039623 0903750339 9385621024 2369025138 6804145779 9569812244 5747178034 1731264532 2041639723 2134044449 4873023154 1767689375 2103068737 8803441700 9395440962 7955898678 7232095124 2689355730 9704509595 6844017555 1988192180 2064052905 5189349475 9260073485 2282101088 1946445442 2231889131 9294689622 0023014437 7026992300 7803085261 1807545192 8877050210 9684249362 7135925187 6077788466 5836150238 9134933331 2231053392 3213624319 2637289106 7050339928 2265263556 2090297986 4247275977 2565508615 4875435748 2647181414 5127000602 3890162077 7322449943 5308899909 5016803281 1219432048 1964387675 8633147985 7191139781 5397807476 1507722117 5082694586 3932045652 0989698555 6781410696 8372884058 7461033781 0544439094 3683583581 3811311689 9385557697 5484149144 5341509129 5407005019 4775486163 0754226417 2939468036 7319805861 8339183285 9913039607 2014455950 4497792120 7612478564 5916160837 0594987860 0697018940 9886400764 4361709334 1727091914 3365013715 7660114803 8143062623 8051432117 3481510055 9013456101 1800790506 3814215270 9308588092 8757034505 0780814545 8819906336 1298279814 1174533927 3120809289 7279222132 9806429468 7824274874 0174505540 6778757083 2373109759 1511776297 8443284747 9081765180 9778726841 6117632503 8612112914 3683437670 2350371116 3307258698 8325871033 6322238109 8090121101 9899176841 4917512331 3401527338 4383723450 0934786049 7929459915 8220125810 4598230925 5287212413 7043614910 2054718554 9611808764 2657651106 0545881475 6044317847 9858453973 1286301625 4487611485 2021706440 4111660766 9505977578 3257039511 0878230827 1064789390 2111569103 9276838453 8633332156 5829659773 1034360323 2254574363 7204124406 4088826737 5843395367 9593123221 3437320995 7498894699 5656473600 7295999839 1288103197 4263125179 7141432012 3112795518 9477817269 1415891177 9919564812 5580018455 0656329528 5985910009 0862180297 7563789259 9916499464 2819302229 3552346674 7593269516 5421402109 1363018194 7227078901 2208728736 1707348649 9981562554 7281137347 9871656952 7489008144 3840532748 3781378246 6917444229 6349147081 5700735254 5707089772 6754693438 2261954686 1533120953 3579238014 6092735102 1011919021 8360675097 3089575289 5774681422 9543394385 4931553396 3038072916 9175846101 4609950550 6480367930 4147236572 0398600735 5076090231 7312501613 2048435836 4817704848 1810991602 4425232716 7219018933 4596378608 7875287017 3935930301 3359011237 1023917126 5904702634 9402830766 8767436386 5132710628 0323174069 3173344823 4356453185 0581353108 5497333507 5996677871 2449058363 6754132890 8624063245 6395357212 5242611702 7802865604 3234942837 3017255744 0583727826 7996031739 3640132876 2770124367 9831144643 6947670531 2724924104 7167001382 4783128656 5064934341 8039004101 7805339505 8772458665 5755229391 5823970841 7729833728 2311525692 6092995942 2400005606 2667867435 7923972454 0848176519 7343626526 8944888552 7202747787 4733598353 6727761407 5917120513 2693448375 2991649980 9360246178 4426757277 6790019191 9070380522 0461232482 3913261043 2719168451 2306023627 8935454324 6176997575 3689041763 6502547851 3824631465 8336383376 0235778992 6729886321 6185839590 3639981838 4582764491 2459809370 4305555961 3797343261 3483049494 9686810895 3569634828 1781288625 3646084203 3946538194 4194571426 6682371839 4918323709 0857485026 6568039897 4406621053 6030640026 0817112665 9954199368 7316094572 2888109207 7882277203 6366844815 3256172841 1769097926 6665522384 6883113718 5299192163 1905201568 6312228207 1559987646 8423552059 2853717578 0765605036 7731309751 9122397388 7224682580 5715974457 4048429878 0735221598 4266766257 8077062019 4304005425 5015831250 3017534094 1171910192 9890384472 5033298802 4501436796 8441694795 9545304591 0313811621 8704567997 8663661746 0595700034 4597011352 5181346006 5655352034 7888117414 9941274826 4152135567 7639403907 1038708818 2338068033 5003804680 0174808220 5910968442 0264464021 8770534010 0318028816 6441530913 9394815640 3192822785 4824145105 0318882518 9970074862 2879421558 9574282021 6657062188 0905780880 5032467699 1297287210 3870736974 0643566745 8920258656 5739785608 5956653410 7035997832 0446336346 4854894976 6388535104 5527298242 2906998488 5369682804 6459745762 6514343590 5093832124 3743333870 5166571490 0590710567 0248879858 0437181512 6100440381 4880407252 4406164290 2247822715 2724112085 0657888387 1249363510 6806365166 7432223277 6775579739 9270376231 9147047323 9551206070 5503992088 4426037087 9084333426 1838413597 0781648295 5371432196 1189503797 7146300075 5597537957 0355227144 9319132172 5564401283 0918050450 0899218705 1211860693 3573153895 9350790300 7367270233 1416532042 3401553741 4426871540 5511647961 1433230248 5440409406 9114561398 7302603951 8281680344 8252543267 3857590056 0432024537 2719291248 6458133344 1698529939 1357478698 9579864394 9802304711 6967157362 2839120181 2731291658 9952759919 2203183723 5682727938 5637331265 4799859124 6327503006 0592567454 9794350881 1929505685 4932593553 1872914180 1136412187 4707526281 0686983013 5760524719 4455932195 5359610452 8303148839 1176930119 6585834314 4248948985 6558425083 4109429502 7719758335 2244291257 3649380754 1711373924 3760143506 8298784932 7129975122 8688196049 8357751587 7178041069 7131966753 4771947922 6365190163 3977128473 9079336111 1914089983 0560336106 0987171783 0554354035 6089529290 8184641437 1392943781 3560482038 9479125745 0770755751 0300242072 6629001809 0422934249 4259060666 1413322872 2698069014 5994511995 4780163991 5141261252 5728280664 3312616574 6938819510 6442167387 1800011004 2184830258 0916543383 7492364118 3888564685 1431500637 3190429514 8146942431 4608952547 0720374055 6691306922 0990804819 4529751106 5046428105 4177552590 9518713188 8359147659 9604131796 0209415308 5855332387 7253802327 2763297737 2143127968 2167162344 2118320180 2881412747 4431688472 1845939278 1435474099 9990722332 0305926297 6611238327 9833169882 5393126200 6503702884 4782866694 0447307947 1047612558 6583752986 2362509998 2323359715 5072338383 3244081525 7781933642 6263043302 6589581708 0045127887 3115935587 7472172564 9470005163 6672577153 9209840950 3274511215 3687300912 1996295227 6591316370 9396860727 1342692623 1547533043 7993316581 1073696431 4217197943 4056391551 2108108136 2626888569 7480680601 1691894175 0272298741 5869917914 5349946244 4194012197 8586013736 6082869072 2365147713 9126874209 6651378756 2059185432 8888341742 9209015631 3328319357 5622089713 7656309785 0156315498 2456445865 4247929357 2282875060 8481453351 3521817295 8793299117 1003247622 2052194645 1053624505 1298843087 1344439507 2442673514 6286179918 3233645983 6963763272 2575691597 2395438305 2086647474 2381511079 2734948369 5239647926 8993698324 9179995027 8950006045 9661313463 3630249499 5148080532 9017902975 1825158750 4900743518 7983511836 0327227726 0171740453 5571658855 5782972910 6195819351 7105548257 9307091005 7635869901 9297217995 1687311755 6314448564 8100220014 2545405542 9273458837 1160209947 9457208237 8043687189 4480563689 1825802444 9963187834 2027491015 3357910727 3362532890 6933474123 8022220116 2627711930 8544850295 4191320040 0999865566 6517756640 9536561978 9781838045 1030356510 1315894589 0287186108 6905893947 1368014845 7001836649 5647203294 3343742989 4642741255 1435905843 4840919548 7015236140 3173913903 6164401984 5505104912 1169792001 2019996050 6994966403 0350863692 9039410070 1945053201 6234872763 2327324494 3963048089 0554251379 7233147518 5207091025 0636859816 7953048181 0073942453 1700238804 7598343234 5041425843 1406361272 1096022824 2337822809 0279765960 7771084939 1517488731 6877713522 3900911711 7350918600 6546200990 2497585277 9254278165 9703834950 5801062615 5333691093 7846597710 5297502231 7307412177 8344189411 8459658610 2980187787 4274456386 6966127724 5038458605 2641510304 0898257777 5447411533 2076407588 1677514975 5380471162 9667771005 8766461595 4967769270 5496239398 5709255070 2740699781 4084312496 5363071866 5337180605 8742242598 1653070525 7383454157 7054292162 9981149175 0861131176 5773172095 6156564786 9547448927 1320608063 5457794624 1453106698 3742113798 1689638235 3330447788 3169339728 7289181036 6408326985 6988254438 5166758622 8993069643 4684897514 8408790396 4760420361 0206021717 3944702634 8763365439 3195229077 3836167389 8117812424 8365578105 0341694515 6362604300 3665743108 4766548777 8012857792 3645418522 4472361713 7422925584 1593135612 8663716703 2807217155 3392646325 7306730639 1085410886 8085742838 5882806023 0334140855 0390973538 7261345119 6292641599 5212789311 3544314601 5273090255 3827104325 9662267439 0374556361 2286139078 3194335705 9003814870 0898661315 3981958574 4233044197 0856696722 2931427307 4138488278 8975588860 7997387044 7020316683 4856941990 9654802982 4931981765 7926829855 6297230106 8277723516 2740783807 4318778273 1821191969 5280051608 7915721288 2633796823 1272562870 0015001829 2975772999 3579094919 6407634428 6157571354 4427898383 0404547027 1019458004 2582021202 3445806303 4503365814 7218549203 6799899729 3535391968 1213319516 5379745399 1114942444 5183033858 8412904018 1781882137 6006659284 9413677543 1745160540 9387110368 7152116404 0582193447 1204482775 9605416948 6453987832 6269548013 9150190389 9593130670 3186616706 6371964025 6928671388 7146631189 1926856826 9199527645 7997718278 7594609616 1721886810 9454651578 8691224106 0981419726 8619255478 7899263153 5947292282 5080542516 9068140107 8179602188 5330762305 5638163164 0192245450 3257656739 2599765175 3080142716 0714308718 8628598360 3746505713 4204670083 4327542302 7704779331 1183666903 2328853068 7387990713 5900740304 9074598895 1364768760 8678443238 2482189306 1757031956 3803230819 7193635672 7419643872 6258706154 3307296370 3812751517 0406005057 5948827238 5634515639 0526577104 2645947604 0556950959 8408889037 6207995663 8801786185 5915944111 7250923132 7977113803

Is there no other place on the Web for this list of digits? A few of them are given in Golden ratio, but none are relevant to the present article about a letter. —Tamfang (talk) 06:54, 15 July 2014 (UTC)

Pronunciation

Fixed and sourced from OED. The Ancient Greek pronunciation could use a better source, though: I just used the automated formatting they have over at Wiktionary. — LlywelynII 04:16, 6 October 2014 (UTC)

The empty set?

Perhaps Jakesyl would like to remind us how a long list of digits is more appropriate to the talk page than the following question, which the digits replaced. —Tamfang (talk) 06:52, 15 July 2014 (UTC)

No mention of phi as the empty set? Barry.carter (talk) 23:07, 11 August 2013 (UTC)

Isn't there something in the article about other symbols that resemble phi? —Tamfang (talk) 09:30, 12 July 2014 (UTC)

Well, good this is here. Otherwise, I wouldn't believe that people could confuse those symbols... — LlywelynII 04:16, 6 October 2014 (UTC)

http://en.wikipedia.org/wiki/Empty_set#Notation — Preceding unsigned comment added by 81.82.234.87 (talk) 14:59, 10 November 2014 (UTC)

Semi-protected edit request on 8 October 2016

To add to existing list ending with line: "In lexical-functional grammar, the function that maps elements from the c-structure to the f-structure."

The symbol for Relative Humidity

92.251.24.209 (talk) 12:03, 8 October 2016 (UTC)

References

Looks like the entry is there. — Andy W. (talk) 00:22, 13 October 2016 (UTC)

Meaning in AI?

In artificial intelligence, a lowercase phi symbol has a standard meaning that escapes me at the moment. Perhaps if someone knows what I'm talking about, it could be added to this page? --5.198.44.45 (talk) 10:58, 15 May 2018 (UTC)

Pronunciation

The article claims: The modern Greek pronunciation of the letter is sometimes encountered in English (as /fiː/) when the letter is being used in [the mathematical/scientific] sense. There is no source for this claim (unless it's the book, which I can't verify). It seems more likely to me that the editor who wrote this heard scientists / mathematicians whose first language is not English simply using their native pronunciations while speaking English. Hairy Dude (talk) 12:55, 28 February 2019 (UTC)

I have personally heard native English speakers pronounce it that way, both scientists and classicists. — Preceding unsigned comment added by 68.172.33.135 (talk) 15:29, 9 March 2019 (UTC)

Semi-protected edit request on 27 February 2019

Upper Case Phi is also used in electrical power engineering a short hand for phase (as in Single Phase = 1Φ, Three Phase = 3Φ, Six Phase = 6Φ) 203.26.73.3 (talk) 05:08, 27 February 2019 (UTC)

Already in the article - "The number of phases in a power system in electrical engineering, for example 1Φ for single phase, 3Φ for three phase." ‑‑ElHef (Meep?) 15:42, 27 February 2019 (UTC)

This is not at all true. Φ is reserved in electrical engineering for magnetic flux. 1Φ is one webber of flux although Wb is more commonly used as an SI unit to avoid confusion with Ø. I can find no documentation in IEEE, NSPE, NCEES that uses Φ for phase. It would be incredibly confusing to use the same symbol. Electrical Engineering uses the symbol Ø. "My high side calculations found 3Φ on AΦ, 2Φ on BΦ, and 3Φ on CΦ in the 3Φ transformer." It should say "My high side caculations found 3Φ on AØ, 2Φ on BØ, and 3Φ on CØ in the 3Ø transformer." That is a lot less confusing because the same symbol doesn't mean two different things in the same sentence.

In mathematics phase can be denoted by Φ,θ,or Ø. Because Φ is flux and θ is phase angle, Ø is used to denote phase. This is the same reason math uses i for imaginary numbers and electrical engineers use j. i is current in electrical engineering. Yet when you type in 'symbol for electrical phase' this page pops up first. This incorrect and uncited claim needs to be fixed ASAP. 74.124.124.66 (talk) 19:57, 20 May 2020 (UTC)

Additional Example for the Use of Phi as a Symbol

Phi is the symbol for the world of Phyrexia in the story of the card game Magic: The Gathering.

Edit: here's an article from wizards of the coast (the company who owns magic: the gathering) about the symbol: https://magic.wizards.com/en/articles/archive/phyrexian-symbol-again-2011-05-18 Dodo Axolotl (talk) 16:26, 28 May 2022 (UTC)

 Not done: please provide reliable sources that support the change you want to be made. Secondary sources are needed to show that this is noteworthy. ScottishFinnishRadish (talk) 16:39, 28 May 2022 (UTC)

Hoping that counts as a reliable source! Dodo Axolotl (talk) 12:04, 2 June 2022 (UTC)

Semi-protected edit request on 8 June 2022

CHANGE "In probability theory, ϕ(x) = (2π)−1⁄2e−x2/2 is the probability density function of the standard normal distribution." to "In probability theory, ϕ(x) = (2π)−1⁄2e−x2/2 is the cumulative distribution function of the standard normal distribution." 138.51.72.65 (talk) 23:15, 8 June 2022 (UTC)

 Not done: please provide reliable sources that support the change you want to be made. ScottishFinnishRadish (talk) 23:22, 8 June 2022 (UTC)