Talk:Why 10 dimensions?

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[edit] Why Why 10 dimensions?

B-) How is this encyclopedic? Why isn't the title nominal? --ESP 06:02, 15 Mar 2004 (UTC)


[edit] What is Encyclopedic?

"Anything academic - Someone or something that would be mentioned in a textbook or research paper, and which is notable or famous at least within its field."

"Why 10 dimensions?" is a topic that is discussed in books such as Michio Kaku's book "Hyperspace" and on prominant websites dealing with string theory. The existing Wikipedia pages on string theory do not cover this issue.

Name of the page.

"Generally, article naming should give priority to what the majority of English speakers would most easily recognize with a reasonable minimum of ambiguity, while at the same time making linking to those articles easy and second nature."

This "name" was taken from sources that discuss this issue such as: http://www.ecf.toronto.edu/~quanv/String/string9.html

If there was a better name in use I would be glad to use it. "Dimensionality of the universe" or "Dimensionality of String Theory" are possibilies, but I have not seen these terms used in the string theory literature in relation to the issue discussed here. JWSchmidt 07:56, 15 Mar 2004 (UTC)

The problem isn't just the name but the entire "talkyness" that pervades the article. Do something, please! HereToHelp (talk) 14:37, 5 November 2005 (UTC)

[edit] Wikibooks for "education"?

I was initially inspired to start the "Why_10_dimensions?" page when I saw this page. However, I have now become aware of the possibility of putting "educational" information into Wikibooks. I am exploring the idea of moving the Why 10 dimensions page to this book. JWSchmidt 15:39, 15 Mar 2004 (UTC)

That sounds like a good idea. --ESP 02:57, 15 Jun 2004 (UTC)
Considering the article's style, it would probably be appropriate for Wikibooks. An article with the name "Reasons for the number of dimensions of the universe" or something similar would however have its place on Wikipedia, so it would be best not to move it but to copy it. Fredrik (talk) 03:34, 15 Jun 2004 (UTC)

[edit] Ramanujan function

Does anyone have a source of the "Ramanujan function" that has terms (D-24) or another "generalized" form with (D-8)?

Maybe one of the references here? I'm not sure how to find these physics articles online.

I could not access online:

A. M. Polyakov, Quantum geometry of bosonic strings, Phys. Lett. B103 (1981), 207.

But this: "Quantum geometry of bosonic strings : revisited" has the following equation: Z=\int_{}^{} D^F [\rho(\xi)]\exp\left(-\frac{26-D}{12\pi} \int_{\xi}^{} \left[ \frac{1}{2} \frac{(\delta_\alpha \rho)^2}{\rho^2} \right] + \int_{\xi}^{} \mu_R^2 \rho^2 \right)

and cites another article by A. M. Polyakov, Phys. Lett. B103 (1981), 211.

as the source of an equation with D = 10 as the critical dimension for a supersymmetric bosonic quantum field. JWSchmidt 03:56, 7 Apr 2004 (UTC)

[edit] Energy loss to higher dimensions

Could someone explain why energy conservation laws works in 3 dimensions (i.e.: no "escape" of energy to higher level dimensions) ? Rama 23:02, 29 Sep 2004 (UTC)

____

In the November 26, 2004 issue of Science magazine, there is an article about attempts to link string theory to experiments:

"a few of string theory's extra dimensions might be wound loosely enough to be detected in {the Large Hadron Collider facility at CERN that should become operational in 2007}. If those dimensions are big enough, matter and energy might disappear into them when high-energy particles collide."

Apparently, string theory predicts that the compact dimensions are only able to take in energy under high-energy conditions that do not normally exist at the low temperature conditions familiar to us on Earth. I think that according to the idea of suppersummetry, under the high-energy conditions of the early universe, there was free exchange of energy between all the dimesions. When the universe cooled, the symmetry broke and some of the spatial dimensions collapsed and could no longer freely exchange energy with our 3 extended spatial dimensions Memenen 04:29, 14 Dec 2004 (UTC)

____

Hmmm, interesting, something like these dimension being "small", and high energy being related to high frequency, so small wavelength, so... makes sense. I should be less lazy and go interview specialists which are available next to me, actually :p Thanks for caring to write ! Rama 07:21, 14 Dec 2004 (UTC)

[edit] Extra Dimentions.

I read with interest the theory that extra spatial dimentions exist. However, this view is at variance with one expressed by Professor Stephen Hawking, who remarked that " if there were more than three spatial dimentions, the orbits of planets around the sun or electrons around a nucleus would be unstable and they would tend to spiral inward." - Derek R Crawford.

The extra dimensions would be far too small to be relevant to planetary orbits, or even atomic orbits. -Lethe | Talk 11:03, Jun 20, 2005 (UTC)

[edit] Lorentz invariance

First, let me say that I agree this is an important topic worthy of encyclopedic discussion, though I'm not sure the title chosen is the best one. Second, I think this article definitely needs a discussion like that in Zwiebach's A First Course in String Theory, where the dimensionality of spacetime is deduced by mandating that string equations of motion be Lorentz invariant. This would give the article a much more solid grounding than a discourse on modular forms. Not that I think the modular form stuff should go! I prefer to have complementary approaches whenever possible; it's just that a bright physics undergraduate could probably grok the Lorentz-invariance explanation in fullness. I've even had some luck explaining 10- or 26-dimensional theories that way to non-science people; lawyers, even.

Anville 12:56, 31 October 2005 (UTC)

The original title of the article was a request for help from a biologist. My hope was that someone who knew the answer would fix the article and give it a new title. --JWSchmidt 13:16, 31 October 2005 (UTC)

[edit] Peer review? Where?

The box at the top of this page has been removed, there is no archived peer review that I can see... QmunkE 08:53, 13 November 2005 (UTC)

[edit] Neccesary road map?

Why 10, 11, or 26 physical dimensions in string theory?

The small section under this subheading is a road-map, not something that is often found in an encyclopedia. I don't think its neccesary, even though published articles might have them.

I'll leave it upto other people to edit, although I would integrate some of the information in that paragraph into the introduction.

[edit] Where is the answer?

I expected to find an explanation of why 10, 11, or 26 dimensions should be more favoured than other numbers, but I can't find the answer in the article. Maybe it is too complicated math, but then what is the relevance of this article? Apus 13:17, 5 September 2006 (UTC)

No kidding. While it's probably dubious to try to bring something so obviously technical into everyday language, the fact that this article exists (and a book, too, apparently) seems to refute that. So, unless some editors here can prove us wrong, I nominate this article for deletion. Those interested in the technical details of string theory can find it at the article about string theory. If there's any extra info available here, merge it into that article, and delete the rest. As it stands now, this article is not accessible to lay audiences. -69.47.186.226 05:06, 8 August 2007 (UTC)

One problem I see is that the "Conformal anomaly" section is an explanation as to why the universe should have 26 dimensions, at variance with the title of the article! Of course that's for bosonic string theory, and superstrings want 10 dimensions. But still... isn't it a bit weird to have more information about 26-dimensional theories than 10-dimensional theories in an article with this title? The section entitled "Modular functions" is also secretly about 26 dimensions, though I can't imagine most readers will see that!

I could write an explanation of "why 10 dimensions" that lay people could get some rough understanding of... but it would require some serious work. Right now the article seems like a mess to me. John Baez 22:08, 25 August 2007 (UTC)

[edit] The "Wikipedia Serious Tone"

To be honest, I'm tired of reading articles from Wikipedia that have no tone to them whatsoever. I congratulate the person who wrote this article, because it's not as boring as the rest.

[edit] Nice article

I think this article should be moved to Wikibooks (but keep a link here). Anyway, I think that it isn't clear for the non-mathematician or non-physicist yet; The main author could extend it.
--Lucas Gallindo 18:09, 9 October 2006 (UTC)

[edit] Advertising

The book is mentioned a little too early for my liking.

I think it's just fine. The book is mentions nearly nowhere else. The article does not resemble an advertisement at all.Leon math 19:24, 23 December 2006 (UTC)

[edit] should be deleted

It's original research. It's a compilation of multiple information sources filtered through the editors' interpretations, it's not the straight dope. Much of it is good, interesting, and useful information, but it doesn't belong in an encyclopedia. A blog, yes, magazine, yes, but not an encyclopedia. 69.137.223.153 06:19, 3 March 2007 (UTC)

[edit] lacking information and is also wrong

Being someone who understands the theoretical background, I absolutely can't see where the article is explaining anything. Where's the x % 4 = 2, x < 10 from the Ricci compactification? Oh, and you know, x=6 is also a viable solution, beside creating somewhat harder equations and being considered as unlikely.