Talk:Riemann zeta function

From Wikipedia, the free encyclopedia

You have new messages (last change).

Can anyone elaborate on the "prime numbers" section? It says "this is a consequence..." without giving even a hint or flavour of why. --P3d0 21:25, Sep 17, 2004 (UTC)

I've added what I believe to be a standard treatment of why the two expansions are equivalent. Do any real mathematicians want to do a better job? -- The Anome 23:27, 17 Sep 2004 (UTC)

I've turned the "vigorous handwaving" into an actual proof and have made a number of further changes and additions. Gene Ward Smith 08:42, 29 Jan 2005 (UTC)

Contents

[edit] Anon edit needs vetting

The following anonymous edit comes from an IP with a very checkered history. It needs vetting:

- \zeta(s) = \prod_{p} \frac{1}{1-p^{-s}} + \zeta(s) = \prod_{p \in primes} \frac{1}{1-p^{-s}}

Thanks. --Wetman 13:02, 18 Apr 2005 (UTC)

This is surely wrong, as it implies that the \zeta function is zero. Oleg Alexandrov 18:15, 18 Apr 2005 (UTC)
I don't see this exact thing in the article though. Oleg Alexandrov 18:18, 18 Apr 2005 (UTC)
Wetman posted a diff; he is talking about the edit from 9:32, 8 April 2005, which Oleg reverted a few hours later anyway. No matter, the edit was fine, the product is over primes. Case closed. linas 22:09, 18 Apr 2005 (UTC)

[edit] perfect powers

Is there a formula out there that relates the zeta function to the perfect powers (1, 4, 8, 9, 16, 25, 27, 32, etc) in a similar way that Euler's product formula does for primes? The reason I ask is because I discovered a very simple one a while back, but I can't find information about any other such formulas. Thanks. --Vagodin 14:47, August 21, 2005 (UTC)

[edit] Pronunciation

Is there a wikipedia policy for where pronunciations should appear? I dislike the redundancy of placing the pronunciation of Riemann both at this article and also at Bernhard Riemann. If a user wants to know the pronunciation they can simply follow the name link to find it. - Gauge 04:44, 2 September 2005 (UTC)

Also, pronunciations should probably be in International Phonetic Alphabet form, as English speakers could pronounce words very differently depending on the dialect. - Gauge 04:48, 2 September 2005 (UTC)
Remove the pronunciation from this article. linas 14:56, 2 September 2005 (UTC)

[edit] Riemann zeta function

I'd like to hold a survey regarding the article Riemann zeta function, to help determine its general comprehensibility and identify areas where it may be incomplete. Please indicate your perceptions of the article below, and feel free to expand the survey or article as you see fit. ‣ᓛᖁ♀ᑐ 21:07, 9 September 2005 (UTC)

The only point I could see this survey having is to determine which users are versed in some complex analysis and those who are not. See also my rant here. Dysprosia 07:57, 11 September 2005 (UTC)

[edit] Comprehensibility

Do you currently understand this article?

Yes

No

  1. ‣ᓛᖁ♀ᑐ 21:07, 9 September 2005 (UTC)
  2. I got a bit lost about halfway through the second paragraph. I also have no idea why the Euler Product Formula has to be proven in the middle of the article. And the bottom of the article is very difficult to follow with only college sophomore math skills. Avocado 00:56, September 10, 2005 (UTC)
  3. — Xiong熊talk* 02:20, 2005 September 12 (UTC)

Comment

  1. I agree with the fact that the proof of the Euler's product formula should not be there. Oleg Alexandrov 04:10, 11 September 2005 (UTC)
  2. I understood most of it up to the point it started talking about Mellin transforms (which is the point at which I lost the will to follow all the links I didn't understand). Before that point, I think the Euler's product proofs should be moved out (but linked to), and a bit more should be said (or linked to) about the "importance of the zeros", in particular what or how path integrals relate to the prime counting function. Hv 11:03, 11 September 2005 (UTC)

If not, do you feel you could understand it after following its internal links?

Yes

  1. ‣ᓛᖁ♀ᑐ 21:07, 9 September 2005 (UTC)

No

  1. Er, well, I found Analytic continuation and Meromorphic function absolutely incomprehensible. I think that if I had time and energy to wade through a huge tree of links it might begin to make a bit more sense, but the motivation is a bit lacking ;-) . On the other hand, I doubt that reading through all the other articles Wikipedia has on math would make it possible to actually follow the mathematical equations and transformations. Avocado 00:56, September 10, 2005 (UTC)
  • Er, well, this article could use improvement. But what's go me stumped is, if you don't know what a meromorphic function is, why in the world are you interested in the Riemann zeta? To answer my own question: probably because of the Clay Institute prize. In which case, the answer is that we need a section, or maybe even a whole article, describing "why the Riemann zeta is important to mathematics", and said article would not make use of formulas at all.
I say this because I object to the idea of somehow "simplifying" this article; its already too simple in many ways, because it is already quite lengthly, while failing to even touch on many important properties and relations. Personally, I would like to see some of the proofs and derivations moved to something in the style of Category:Article proofs. -- linas 17:03, 11 September 2005 (UTC)

[edit] Completeness

The article's lead section states the Riemann zeta function is "of paramount importance in number theory". From reading the article, do you understand why this function is important?

Yes

No

  1. ‣ᓛᖁ♀ᑐ 21:07, 9 September 2005 (UTC)
  2. Sort of. It has something to do with prime numbers (which I know are a knotty number theory problem) but I'm pretty sure I couldn't figure out from this article what exactly the connection is. Avocado 00:58, September 10, 2005 (UTC)

[edit] Joe test failure

Disclosure: I am the son of a world-famous mathematician -- indeed, in her later life a number theorist. However, she mated with a whiskey-soaked advertising copywriter and I was raised on a farm by psychopathic semi-deaf-mutes shunned by their neighbors for the worldly sin of using electricity and automobiles. Mother did not rescue me from this Appalachian pastoral idyll for many years, whereupon she made my bedtime tales out of graph theory.

So, I have only half the genes and half the nurture. I have managed to stagger through a computer engineering career with nothing higher than the calculus -- which only served me once, and that indirectly. On the brighter side, I'm generally able to comprehend intelligent explanations, often in polynomial time.

As it stands, I find this article to be incomprehensible and without merit here. Wikipedia is a general reference work. For content to be included here, it has to pass the Joe test: If you had unlimited time in which to explain it (in far more detail than here) to Joe, the Everyman; if Joe was completely cooperative, intelligent, and patient; if eventually he understood all you intend, then could he imagine any possible way in which this subject might be of interest? This topic fails the Joe test.

This article bears a disturbing resemblance to Graveler. It is an isolated swatch of factoplasm lifted out of a highly specialized context, meaningless outside that context. Nothing has been done to show that it has any application to the Real World. While the subject may be a vital part of its own bubble universe, nothing in the article connects it to anything outside.

To be sure, this is longer than Graveler, and arguably factual; but I think that by the time you get past definitions of terms, it is equally valid to say that it is very like a playing card in a mathematical game. If there is a connection to anything concrete, that needs to be shown.

So, I suggest the article be downsized to a bare description of the function and merged into its parent article. (It does at least have some relationship to a larger mathematical topic, does it not?)

Another possibility is to open a new WikiBook entitled "Higher Mathematics" and expand this article into a whole chapter -- there.

I hold out one other route for improvement. I almost began to see a glimmer of light in Applications. Perhaps a diligent effort could actually find some application of this function to something tangible. If so, rewrite this section and move it to the introduction. MBAs and fools like me can read the 4 or 5 sentences that place the function in context, and then we can graze on.

— Xiong熊talk* 05:11, 2005 September 12 (UTC)

So, removing the rhetoric, your proposal for making this article more accessible seems to be to make it smaller or to remove it from Wikipedia completely. I don't see how either of these routes will improve Wikipedia. Gandalf61 11:39, September 12, 2005 (UTC)
To paraphrase, Xiong seems to be saying "I'm the product of a broken social/cultural system, and have no education. I am self-taught, having learned engineering, but otherwise, I'm ignorant. I want to stay ignorant, and everyone else should be kept ignorant too". This sounds nothing so much like the Chinese cultural revolution, where villagers melted down the strong steel of mathematical theorems into puddles of worthless self-taught folk knowledge, and starved by the millions as a result. Shall we picture the "MBA's and fools like him" holding machine guns, eating 4 or 5 rice cakes "in context", and then grazing on? This is a tragedy. linas 14:36, 12 September 2005 (UTC)

Aside from psychoanalysis of this person (is he (or she) really Chinese), he has some point. But he is questioning how wikipedia should be written, and this is probably not a place to do. There are many, too many, hopelessly technical pages already. But the consensus is we should try to revise it so that laymen can understand it, not that eliminate or downsize it from wikipedia. -- Taku 03:31, 14 September 2005 (UTC)

Agree with Taku. And I will say again: please, when you notice a page is too technical, don't just slap a template and walk away. First try to read carefully the page, and see if your criticism is justified. If yes, write at least something on the talk page explaining what you wish were better. That is, be constructive. Oleg Alexandrov 03:57, 14 September 2005 (UTC)
Guess what..the Zeta function IS technical! Maybe "Joe Test" should read a damn book about number theory.

And no matter how uninteresting "Joe" might find this, im sure he's interested by the fact that the Riemann Hypothesis one of the Millenium Problems. As for being useless, this problem is closely related to the primes. Both the distribution of primes and primality testing are two of the biggest problems in number theory, both of which are closely related to cyptanalysis, which is certainly useful. -- He Who Is[ Talk ] 01:58, 29 June 2006 (UTC)

[edit] Removed text

I removed the following text:

The Möbius function also relates to the zeta function and Bernoulli numbers in the coefficients in series expansion of {\zeta(n + 2)} \over {\zeta(n)} with the formula
∑ μ(d)d2
d | n
for which A046970 gives values for the first 60 n.

I couldn't understand what it was trying to say. Its trying to describe some dirichlet series maybe??. linas 00:46, 21 December 2005 (UTC)

I spose i was trying to justify the oeis having a ref to this article. Numerao 21:33, 29 December 2005 (UTC)

[edit] An easier proof (for the layperson)

I found this section very helpful for understanding the connection between the Zeta function and prime numbers. BringCocaColaBack 11:29, 13 January 2006 (UTC)

[edit] Hyphens

Is this function called the zeta-function or the zeta function? The article uses both. toad (t) 12:10, 10 February 2006 (UTC)

Some anon editor ran around adding hyphens recently, which no one reverted. Not just here, but in half-a-dozen articles. :-( 15:05, 10 February 2006 (UTC)

Zeta-function refers to all zeta function is general. But in this case its just Riemann zeta function. -- He Who Is[ Talk ] 01:59, 29 June 2006 (UTC)

[edit] Question moved from article

Following question from an anon contributor moved from the Globallly convergent series section on the article page. Gandalf61 08:35, 20 April 2006 (UTC)

Why is there a function of s only (zeta of s), that equals a sum which leaves behind a function of s and x?


That question applies more properly to the formula in the section above Globally convergent series, called Series expansions, which contains the formula:

\zeta(s) = \frac{1}{s-1} - \sum_{n=1}^\infty (\zeta(s+n)-1)\frac{x^{\overline{n}}}{(n+1)!}

What's that 'x' doing there? -GTBacchus(talk) 13:38, 20 April 2006 (UTC)

I think that's supposed to be an s not an x, then it would look almost right (?). You can check correctness by going to the article on the Hurwitz zeta function, then look at the section called "Taylor series", where it mumbles about derivatives, and with a few minor substitutions (e.g. y=-1), you should be able to derive the above (with an s where x now stands). linas 04:16, 21 April 2006 (UTC)

[edit] Series Expansion

In the series expansion section, it's written that "Another series development valid for the entire complex plane is.." I can't figure out what the variable 'x' is supposed to be in the expansion that follows. x=s? —The preceding unsigned comment was added by 12.208.117.177 (talk • contribs) .

Ok, that's twice it's come up; I've changed it from x to s. -GTBacchus(talk) 05:54, 11 May 2006 (UTC)

[edit] Third moment of the Riemann zeta function?

The article titled 42 (number) says:

It is believed to be the third moment of the Riemann zeta function, based partially upon evidence from quantum mechanics.

I don't know what this means. Here's a guess:

\int_{(-\infty,\infty)} s^3 \zeta(s)\,ds = 42.

I'm accustomed to the definition of momnets of probability measures; if ζ were a probability density function then the integral above would be the third moment of the corresponding probability distribution. But ζ is negative in some places, and from the way ζ(s) blows up at s = 1 it seems we'd have to be thinking of a Cauchy principal value or something like that.

Can someone make the article's statement clearer? Michael Hardy 17:52, 5 July 2006 (UTC)

I've exchanged some email with John Baez, the mathematical physicist who has edited Wikipedia articles as user:John Baez, and he reports that he cannot access Wikipedia because he is in China. He wrote:
   
“
 So, feel free to post this comment for me:

I don't know anything about the "3rd moment of the Riemann zeta function", but perhaps what's meant is the 3rd moment of the distribution of spacings between zeroes of the Riemann zeta function. There's a lot of evidence relating the distribution of these spacings to the distribution of spaces between eigenvalues of a large random self-adjoint matrix. For lots more, try this:

http://www.maths.ex.ac.uk/~mwatkins/zeta/bump-gue.htm

and for general connections between the Riemann zeta function and quantum mechanics, try:

http://www.maths.ex.ac.uk/~mwatkins/zeta/physics1.htm

Best, jb
   
”
My wild guess seemed so implausible that I'm both relieved to hear that it's wrong and pleased to hear that this otherwise implausible-seeming statement can be construed in such a way that it makes sense. Michael Hardy 16:20, 20 July 2006 (UTC)

[edit] Surprising omission

No graphic of the graph in the complex plane? Surely the article should include one or perhaps three; real part, imaginary part and absolute value, as is the standard on Mathworld. Soo 14:17, 16 July 2006 (UTC)

lucky this is WP and not planetmath, or you would've gotten hooted at big time. anyway, yeah, it would be nice to have some kind of graphic. Numerao 20:18, 17 July 2006 (UTC)

[edit] Question on Trivial Zeros

The trivial zeros do not seem to yield zeros:

For example: \zeta(-2) = 1 + \frac{1}{2^{-2}} + \frac{1}{3^{-2}} + \cdots = 1 + 2^2 + 3^2 + \cdots;

which yields infinity.

I will appreciate if someone lets me know where I am mistaken.

As the article says, the power series only defines the Riemann zeta function for arguments x > 1. You must use the function's analytic continuation to evaluate it elsewhere. Fredrik Johansson 18:46, 26 August 2006 (UTC)

[edit] graph of zeta

I stored in commons a graph of zeta (x) with -20 < x < 10.

see

Riemann zeta function for real -20 < s < 10. The green graph is 100*zeta(x), -13 < x < -1
Enlarge
Riemann zeta function for real -20 < s < 10. The green graph is 100*zeta(x), -13 < x < -1

Perhaps it can go into the article

--Brf 10:05, 31 August 2006 (UTC)

[edit] An alternative elementary formulation for Zeta function

In a technical report entitled "[http://cswww.essex.ac.uk/technical-reports/2005/csm-442.pdf An elementary formulation of Riemann’s Zeta function]", myself (Riccardo Poli) and Bill Langdon provided a very simple proof that, for \Re(s)>1, Riemann's Zeta function can be written as \zeta(s)=1+\sum_{k=1}^\infty a_k(s) p_k^{-s} where a_k(s)=\prod_{j=k}^\infty (1-p_j^{-s})^{-1}.

We are not experts in number theory, but we have searched widely and also asked several mathematicians: it appears that our rewrite is new. These people tell us that this is useful formulation. So, we were wondering whether it would make sense to include it in the article.

Yes, this follows from the fact that
a_k(s)=\sum_{m \in \mathbb P_k}m^{-s}
where \mathbb P_k is the set of integers whose smallest prime factor is greater than pk. If this result is published in a textbook or refereed journal then it can be included it in the article. If not, however, then it falls under Wikipedia:No original research and cannot be included. Gandalf61 09:27, 27 October 2006 (UTC)

[edit] Critical Strip

Can someone add an explanation about the critical strip? This term's definition is nowhere to be found in Wikipedia. Thanks! By the way, the whole article is fine and readable; everybody with a college degree will understand at least the basics. Hugo Dufort 08:28, 14 November 2006 (UTC)

Okay, done that. Gandalf61 09:54, 14 November 2006 (UTC)
Thanks a lot! The added information greatly helps understanding some key concepts. Every specialized term needs to be defined, unless people not familiar with the subject will be lost on the way. Even before the arid math proofs! Hugo Dufort 04:16, 15 November 2006 (UTC)
Retrieved from "http://en.wikipedia.org../../../r/i/e/Talk%7ERiemann_zeta_function_d3f5.html"