Talk:Peter Gustav Lejeune Dirichlet

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Pronunciation (1)[edit]

Anybody know how to pronounce his name? It would be nice to have pronounciation guides since most of us just read the names of the dead guys... — Preceding unsigned comment added by 69.220.112.219 (talk • contribs) 18:51, 1 May 2005‎

My last undergrad math prof said /DAYRSH-lay/ which can't be right. I'm tempted to pronounce it French-like, maybe /Day-hreesh-LAY/? We could use an IPA at the head of the article from someone who's certain what's right. — Preceding unsigned comment added by 74.132.209.231 (talk • contribs) 15:47, 12 August 2006‎

In Russian we pronounce his name in a French way: without 't' at the end, and 'ch' is pronounced as 'hh'. Something like [Dee-ree-hlé]. I think it resembles the original pronuciation. Crocodealer 9 July 2005 11:43 (UTC)

I've heard his surname pronounced both as French (dee-ree-SHLEH) and as in German (DEE-rikh-let)... Which is right? --Army1987 22:21, 18 December 2006 (UTC)[reply]

it's ambiguous, since his family is from french-speaking belgium, but he seems to have lived in german-speaking areas (Düren, Berlin, Göttingen).

the french way would be to pronounce the "ch" as english's "sh". the german way would be as a "k". one website claims the french way, but more credible sites (including wikipedia at present) use the german way — Preceding unsigned comment added by 70.239.166.141 (talk • contribs) 18:03, 17 March 2007‎

http://www.pronounceitright.com/pronounce/2871/johann-peter-gustav-lejeune-dirichlet has the German pronunciation as audio, which however interprets the spelling as French--so "ch" comes out "sh," "et" comes out "ay," and the accent is on the last syllable. The horror is that the name _is_ derived from French, but the spelling is German! Note that the sound of "ch" in German is quite different after a front vowel (e or i) than after a back vowel (a, o, or u): "ach" is close to "ahk," but "ich" is closer to "ish" than "ick." (I speak both French and German, if not well.) A French spelling of the name, as the article points out, would be "De Richelette"; and a reasonable English pronunciation would be "DirishLET." The pronunciation advocated by Wikipedia makes no sense at all, since it is neither French nor German. It is, however, a good match to the first audio pronunciation at http://fr.forvo.com/word/dirichlet/ (also by a German speaker). The second pronunciation there matches the one I started with. In sum, Wikipedia has ranged itself with the ignorant; but they are in the majority--in America, Germany, and--judging from the above--in Russia. So these are your choices: (1) you can be hip like me and say "DirishLET," and most everyone will think you're weird if not dumb; (2) you can say "DirishLAY," and everyone except educated German and French persons will think you're dumb; (3) you can take Wikipedia's advice and say "DiriKLAY" like the rest of the dummies, and everyone will think you're a mathematician. (I'm not really hip, just feeble as a humorist.) Halfb1t (talk) 08:37, 1 December 2012 (UTC)[reply]

Primes in an arithmetic sequence[edit]

Dirichlet is famous for proving that there are infinitely many primes in any arithmetic sequence where the terms are relatively prime. The guy started analytic number theory... there should be some mention of that. --Dantheox 04:41, 28 June 2006 (UTC)[reply]

The modern formal definition of function[edit]

I presume this means the notion of a function as a set of ordered pairs. I just want to see some evidence. At least one writer (Wiener 1914) attributes this notion to Schröder:

"what we have done is practically to revert to Schröder's treatment of a relation as a class of ordered couples"(cf Norbert Wiener 1914 A simplification of the logic of relations reprinted in van Heijenoort, Jean (1967, 3rd printing 1976), From Frege to Gödel: A Source Book in Mathematical Logic, 1879-1931, Harvard University Press, Cambridge MA, ISBN 0-674-32449-8)

Wiener's reduction of the theory of relation to class (cf commentary in van Heijenoort 1967:224) was carried forward by Hausdorff (1914) and Kuratowski (1921) into the notion of ordered pair set theory uses today. And whether the ZFC definition is the definition of function as far as I'm concerned is also open to debate (I'm researching this. For example, the notion also appears in Bertrand Russell's 1903 without attribution to anyone). Bill Wvbailey (talk) 15:18, 7 August 2009 (UTC)[reply]

Pronunciation (2)[edit]

It sometimes gets annoying when Wikipedia tries to be too pedantically accurate. Hence the "German" pronunciation with hard k. Certainly every time I've heard this name pronounced in English it sounds more like "DEAR-ish-lay". But each to his own. Benwing (talk) 06:22, 12 March 2012 (UTC)[reply]

I say /dɨˈɻɪklɪt/, Susskind says /ˈdiɻɪʃleː/, history says /diriˈkleː/. It's Belgian borrowed into German, anything could have happened. ᛭ LokiClock (talk) 22:15, 29 December 2012 (UTC)[reply]

Correction, it is said /diʀiˈʃleː/ by some Germans, according to German wiki. English pronunciations should be given, but they'll all come out with the same adjustments of the German versions. ᛭ LokiClock (talk) 22:25, 29 December 2012 (UTC)[reply]

The correct pronunciation has a hard 't' at the end in addition to the part the OP objects to (Source: Personal conversation with Eugenio Calabi).Julzes (talk) 19:08, 22 July 2015 (UTC) Julzes (talk) 19:08, 22 July 2015 (UTC)[reply]

That is, if by correct is meant how he was addressed when living. If we go by how people have agreed or not since then, I wouldn't expect people to get it this version of 'right' any more than I'd expect a 10-year old autodidact to correctly pronounce Euler. Julzes (talk) 19:11, 22 July 2015 (UTC)[reply]

Halfb1t in the first section on this seems to have it entirely right (i.e., getting it right will probably have almost everybody look at you like you're a fool even near where he actually lived and worked. Julzes (talk) 19:18, 22 July 2015 (UTC)[reply]

Dubious[edit]

I cannot find any references towards Dirichlet's Brain being preserved at a University published before 13 May 2010‎, when this sentence was added on Wikipedia with the sole exception of this. However, the reviews look less than optimal...

https://www.researchgate.net/publication/258104086_A_rare_anatomical_variation_newly_identifies_the_brains_of_CF_Gauss_and_CH_Fuchs_in_a_collection_at_the_University_of_Gottingen Nickpips (talk) 01:03, 17 July 2015 (UTC)[reply]

Gustav Lejeune Dirichlet doctoral advisors in error[edit]

Gustav Lejeune Dirichlet did not have Fourier and Poisson as doctoral advisors. Indeed, he left Paris without a PhD. Please show citation or other reliable evidence for Poisson and Fourier! Even if it were true, I don't think it could ever have worked; although Fourier and Poisson were friends in their student days, after 1808 they quickly became mortal enemies. Reason was related to Fourier's superior analytical abilities, which proved superior to Poisson's "human math transformer" abilities.

Here is a quote from Mactutor http://www-history.mcs.st-andrews.ac.uk/Biographies/Dirichlet.html "On 28 November 1825 General Foy died and Dirichlet decided to return to Germany. He was encouraged in this by Alexander von Humboldt who made recommendations on his behalf. There was a problem for Dirichlet since in order to teach in a German university he needed an habilitation. Although Dirichlet could easily submit an habilitation thesis, this was not allowed since he did not hold a doctorate, nor could he speak Latin, a requirement in the early nineteenth century. The problem was nicely solved by the University of Cologne giving Dirichlet an honorary doctorate, thus allowing him to submit his habilitation thesis on polynomials with a special class of prime divisors to the University of Breslau."

75.148.94.222 (talk) 20:43, 25 November 2015 (UTC) Al Roxburgh[reply]

You are right, that is also clear from reading the article, the only confusion was in the infobox. To remove confusion, I replaced 'academic advisors' with 'influences' in infobox, and also added Gauss which is a clear influence from the article and sources. AdamSmithee (talk) 12:02, 23 February 2016 (UTC)[reply]

Merger proposal[edit]

I would propose to merge Rebecka Mendelssohn into Peter Gustav Lejeune Dirichlet . Lejeune Dirichlet's wife Rebecka does not meet WP:NOTABLE, save that she is his spouse and a member of the Mendelssohn family. The article itself records her only as a passive figure in the lives of her family members. There is little or nothing that can be added to the existing Rebecka Mendelssohn article, save for her children by Lejeune Dirichlet, who are already mentioned in the latter's article. The Lejeune Dirichlet article already covers much of the content of Rebecka Mendelssohn as to her background, so adding the remaining details will not distort it; thus the merger will not cause any problems as far as article size is concerned. Smerus (talk) 07:32, 12 June 2020 (UTC)[reply]

Merger complete. Klbrain (talk) 22:02, 26 December 2020 (UTC)[reply]