Origins of Mathematical Symbols/Names - MathOverflow most recent 30 from http://mathoverflow.net2013-05-22T18:52:12Zhttp://mathoverflow.net/feeds/question/8295http://www.creativecommons.org/licenses/by-nc/2.5/rdfhttp://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-namesOrigins of Mathematical Symbols/Namesliuyao2009-12-09T02:49:17Z2010-05-02T14:45:35Z
<p>I'm not sure if this has been asked. I'll explain the question by an example.</p>
<p>Fields are often denoted by the letter k, which comes from the German word Körper, meaning body (like corpse, corporeal).</p>
<p>Most mathematical symbols relate directly or indirectly to the English names, so what other exceptions are there?</p>
<p>(Yes, this is inspired by the other post about languages in math)</p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8297#8297Answer by Kevin Lin for Origins of Mathematical Symbols/NamesKevin Lin2009-12-09T03:04:36Z2009-12-09T03:04:36Z<p>$\mathbb{Z}$ comes from the German "Zahlen" which means "numbers".</p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8299#8299Answer by Kevin Lin for Origins of Mathematical Symbols/NamesKevin Lin2009-12-09T03:09:24Z2009-12-09T03:15:29Z<p>The notation $\mathcal{F}$ for sheaves comes from the French word "faisceau" meaning "bundle". </p>
<p>Also "gerbe" means "sheaf" in French.</p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8300#8300Answer by Kevin Lin for Origins of Mathematical Symbols/NamesKevin Lin2009-12-09T03:11:22Z2009-12-11T17:27:41Z<p>I've been told that the notation $\mathcal{O}$ for the structure sheaf of a scheme/variety/whatever comes from the Italian word "olomorfo/olomorfa" for "holomorphic".</p>
<p>I should note that I don't have any evidence for this claim beyond "I heard it somewhere from somebody". It would be great if anybody could corroborate this.</p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8302#8302Answer by liuyao for Origins of Mathematical Symbols/Namesliuyao2009-12-09T03:19:28Z2009-12-09T03:19:28Z<p>Center of a group is denoted Z, from German word Zentrum</p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8303#8303Answer by MLevi for Origins of Mathematical Symbols/NamesMLevi2009-12-09T03:28:50Z2009-12-09T03:28:50Z<p>As an undergraduate, I was told that $V$ is often used to denote a neighborhood because the French translation is <em>voisinage</em>. Anyone else hear this? </p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8304#8304Answer by REDace0 for Origins of Mathematical Symbols/NamesREDace02009-12-09T03:33:50Z2009-12-09T03:33:50Z<p>Wolfram has nice a little paragraph on the history of the term "Ring" right after the list of ring axioms.</p>
<p><a href="http://mathworld.wolfram.com/Ring.html" rel="nofollow">Ring (from Wolfram Mathworld)</a></p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8305#8305Answer by liuyao for Origins of Mathematical Symbols/Namesliuyao2009-12-09T03:34:55Z2009-12-09T03:34:55Z<p>In homological algebra, one sometimes uses Z and B to denote cycles (or closed form) and boundaries (or exact forms), respectively. Z must be for Zycle.</p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8341#8341Answer by axiomsofchoice for Origins of Mathematical Symbols/Namesaxiomsofchoice2009-12-09T13:04:07Z2009-12-09T13:04:07Z<p>You might like to take a look at this site:</p>
<p><a href="http://jeff560.tripod.com/mathsym.html" rel="nofollow">Earliest Uses of Various Mathematical Symbols</a></p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8342#8342Answer by Harald Hanche-Olsen for Origins of Mathematical Symbols/NamesHarald Hanche-Olsen2009-12-09T13:10:27Z2009-12-09T17:09:00Z<blockquote>
<p>Utile erit scribit ∫ pro omnia.
(It is useful to write ∫ instead of omnia)
– Leibniz (1675-10-29)</p>
</blockquote>
<p>(Source for this quotiation: Eriksson, Estep, Hansbo, Johnson: Computational differential equations, end of Ch. 3)</p>
<p>In response to some comments: <em>omnis</em> <a href="http://www.archives.nd.edu/cgi-bin/lookup.pl?stem=omnis&ending=" rel="nofollow">means “all”</a>. Compare <em>omnivore</em>. Here endeth the Latin lesson.</p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8350#8350Answer by Kevin Lin for Origins of Mathematical Symbols/NamesKevin Lin2009-12-09T14:06:29Z2009-12-11T17:28:52Z<p>I've heard that the "$K$" of $K$-theory comes from the German word "Klasse(n)" meaning "class(es)", but I don't have any concrete evidence for this.</p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8352#8352Answer by SixWingedSeraph for Origins of Mathematical Symbols/NamesSixWingedSeraph2009-12-09T14:27:54Z2009-12-09T14:27:54Z<p>Pat Ballew's blog <a href="http://www.pballew.net/etyindex.html" rel="nofollow">Math Words</a> has interesting stuff. </p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8356#8356Answer by psihodelia for Origins of Mathematical Symbols/Namespsihodelia2009-12-09T15:11:47Z2009-12-09T15:11:47Z<p>$\mathbb{N}$ comes from the German "Natürliche Zahlen"=natural number<br>
$\mathbb{Z}$ comes from the German "ganZe Zahl"=integer numbers<br>
$\mathbb{Q}$ comes from the Latin "Quotient"= result of a division<br>
$\mathbb{R}$ comes from the German "Reelle Zahl"=real numbers<br>
$\mathbb{C}$ comes from the French "nombre Complexe"=complex numbers<br></p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8359#8359Answer by Joseph Malkevitch for Origins of Mathematical Symbols/NamesJoseph Malkevitch2009-12-09T15:52:56Z2009-12-09T15:52:56Z<p>There is a "classic" book about the history of mathematical notations by Florian Cajori though there has been some "revision" of his work by more recent scholars.</p>
<p><a href="http://en.wikipedia.org/wiki/Florian_Cajori" rel="nofollow">http://en.wikipedia.org/wiki/Florian_Cajori</a></p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8375#8375Answer by Theo Johnson-Freyd for Origins of Mathematical Symbols/NamesTheo Johnson-Freyd2009-12-09T17:32:53Z2009-12-09T17:32:53Z<p>$x,y,z$, and in particular that $x$ is the independent variable and $y$ the dependent variable, are due to Descartes, if I'm not mistaken.</p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8601#8601Answer by Vectornaut for Origins of Mathematical Symbols/NamesVectornaut2009-12-11T20:28:20Z2009-12-11T20:28:20Z<p>This one is pretty well-known: the notation $e$ for the identity of a group comes from the German word <em>Einheit</em>, meaning <em>unit</em>.</p>
<p>I'd be willing to bet that the notation $G$ for a group also comes from German... but we don't notice, because the German word for <em>group</em> is <em>Gruppe</em>!</p>
<p><hr /></p>
<p><a href="http://ncatlab.org/nlab/show/partition+function" rel="nofollow">Here's a fun one</a>: the notation $Z$ for a topological quantum field theory comes indirectly from the notation $Z$ for a partition function in statistical mechanics, which comes from the German word <em>Zustandssumme</em>, meaning <em>state sum</em>. I said "indirectly" because partition function in quantum field theory isn't a statistical-mechanical partition function... it just looks like one after you Wick rotate! (Then again, maybe there's a deeper sense in which the QFT partition function really <em>is</em> a statistical-mechanical partition function. Does anybody know?)</p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8604#8604Answer by Konrad Swanepoel for Origins of Mathematical Symbols/NamesKonrad Swanepoel2009-12-11T20:44:55Z2009-12-11T20:44:55Z<p><em>F</em> for a closed set comes from the French <em>ferme</em> (=firm, cf. <em>fermer</em>=to close).</p>
<p>What about <em>G</em> for an open set? Is this also an example of the next-letter phenomenon? (as in Michael's comment to <a href="http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/8303#8303" rel="nofollow">this answer</a> to the question.)</p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/21150#21150Answer by Jamie Weigandt for Origins of Mathematical Symbols/NamesJamie Weigandt2010-04-12T20:02:08Z2010-04-12T20:02:08Z<p>I <a href="http://mathoverflow.net/questions/19264/what-is-the-etymology-for-the-term-conductor" rel="nofollow">asked a while ago</a> about the etymology of the name <em>conductor</em>. Often the conductor of an order in a number field is denoted by $\mathfrak f$. This comes from the original German name <em>Führer</em> given by Dedekind.</p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/21155#21155Answer by Harry Gindi for Origins of Mathematical Symbols/NamesHarry Gindi2010-04-12T20:47:56Z2010-04-12T20:47:56Z<p>Oh, but of course $\emptyset$ comes from Bourbaki. Interestingly, so does $\Rightarrow$ to denote implication, and $\in$ instead of $\varepsilon$. The "Dangerous bend" comes from Bourbaki as well.</p>
<p>However, my all time favorite is the set of associated primes of a module M. $Ass(M)$ is in fact called the <em>assassinator</em> of $M$, and its elements are called <em>assassins</em>. </p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/21163#21163Answer by Andy for Origins of Mathematical Symbols/NamesAndy2010-04-12T23:18:25Z2010-04-12T23:18:25Z<p>In design theory we talk of a t-(v,k,λ). I think v originally meant "varieties", but I don't know if any of the other symbols meant anything; it would be nice to find out that they did. λ seems an odd choice for an integer... in many other contexts it gets used as a real number.</p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/21432#21432Answer by Qfwfq for Origins of Mathematical Symbols/NamesQfwfq2010-04-15T08:19:04Z2010-04-15T08:19:04Z<p>$E$ is sometimes used for vector spaces, from the French word "espace"="space". </p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/21434#21434Answer by Keivan Karai for Origins of Mathematical Symbols/NamesKeivan Karai2010-04-15T08:53:28Z2010-04-15T13:39:39Z<p>The letter $T$ in the names for the separation axioms $T_1$, $T_2$, etc
in point set topology comes from "Trennungsaxiom" in German.
<a href="http://de.wikipedia.org/wiki/Trennungsaxiom" rel="nofollow">http://de.wikipedia.org/wiki/Trennungsaxiom</a></p>
http://mathoverflow.net/questions/8295/origins-of-mathematical-symbols-names/23258#23258Answer by Pádraig Ó Conbhuí for Origins of Mathematical Symbols/NamesPádraig Ó Conbhuí2010-05-02T14:45:35Z2010-05-02T14:45:35Z<p>I'm not sure how relevant this is outside of Ireland, but while doing basic mechanics, if you ever see acceleration denoted as $f$, as it is in the "log tables" here, as in $v=u+ft$, the $f$ in this case stands for the Latin for acceleration, festinatio (with festino meaning "I hurry", so festinatio would very roughly and more literally translate as "hurriedness"), which is funny because adcelero is the Latin for "I speed up" which looks a lot more like acceleration.</p>
<p>Similarly, displacement denoted by $s$ as in $s=ut+\frac12 at^2$ is from the Latin for displacement, summoveo (with moveo meaning "I move [something]").</p>
<p>And, of course, velocitas, the Latin for speed. I can imagine u being used for velocity as well since the Romans actually pronounced "v" as "u", so the two are pretty much interchangeable.</p>