Talk:String theory/Archive 2

message: I don't think the string has so much dimensions but capabilities. The string would need to built of a super partical that operates in all dimensions. A Dimension is a concept. strings are built of super particals. the universe is a Haze of identical particals. how can I explain. . . like cells in the body. All cells are basically the same but choose to take on different functions to support a fully functioning body. All particals in the universe are ultimately the same they take turns in managing energy and motion in different dimensions. Thats why strings vibrate in so many ways. Its like a shimmer across the strings surface as each superpartical rotates work. like an octopus skin changing color.
Is that correct??. . the partical would be immensily complex yet not complex at all. it has no begining or end it is a cirlce. . a 10 11 26 or whatever dimensioned circle. the number of capabilities depend on the number of dimensions.
How many different properties of the universe are need in order to have the universe sustain itsself. Is it actually sustaining its own operation. . How long in relation to what exists beyond the universe is a second. What exactly is the universe?? Why does it move in way it does. What makes a string??? Find out what makes a string and you have found the first piece of the puzzle. What is a super partical how are they woven into a string. —The preceding unsigned comment was added by 194.237.142.11 (talk • contribs) 16:07, 2 February 2006  (UTC)
:Not to beat down the new guy, but this talk page really needs a statement to the effect: Please only make comments relevant to improving the string theory article. Please refrain from rambling on about your personal philosophy of what you think string theory may or may not be. See Wikipedia:Talk page guidelines. -- Fropuff 16:53, 2 February 2006 (UTC)
thread_title: Anon comment

message: Some IP has been deleting things from the tallk page. Cf. this edit and these edits. I didn't check back further. The IPs check out as in Ontario, Canada. Probably nothing to worry about, but worth keeping an eye out for. –Joke 22:52, 13 March 2006 (UTC)
thread_title: Weird anonymous deletions

message: To say that string theory is not testable is incorrect.  String theory can be tested by picking up an ball and observing it leave your hand and hit the ground.  This is called gravity.  String theory predicts gravity.  Gravity has been a confirmed prediction of string theory.  I will soon remove all statements from the article that claims that string theory is not falsifiable, because it is not true.Atraxani 04:36, 19 March 2006 (UTC)
replies: text: I assume by the absense of any responses that all of you agree with me.Atraxani 00:18, 20 March 2006 (UTC)

text: What an odd claim.  A "test" of string theory must by definition distinguish between it and other theories purporting to explain the same physics.  Your "drop a ball" test fails to distinguish between string theory, general relativity, Newtonian gravity, or even "fixed -9.8m/s^2 radial acceleration".  Also note that gravity is a "postdiction" of string theory: truly convincing tests would involve predictions of previously unobserved phenomena.  (Mind you, even just getting the known particle spectrum right would probably be plenty for me.)--Steuard 18:22, 20 March 2006 (UTC)
replies: text: String "theory" is not a complete theory but rather a collection of interesting theoretical ideas.  There are many many different string models and none of them (as yet) make contact with the Standard Model.  The big problem (as I as an experimental physicist see it) is that there is still SO much freedom in string theories that pretty well anything we discover at the LHC won't be able to kill it.  As for Atraxani's comment, since string theory can't begin to answer the question "How many different types of higgs particles are there?", (or rather, as it CAN answer it with any number experimentalists eventually detect) the theory in this respect is not testable.  When someone makes a string theory that connects to the Standard Model I will be very impressed.  Until then the use of the word "theory" in String Theory is just wrong.141.151.89.144 02:17, 3 July 2006 (UTC)
thread_title: String theory is indeed testable and falsifiable and verifiable

message: The formula explaining why there are 26 dimensions is meaningless without explaining what the simbols (such as \rho) stand for. Since there is a reference cited anyway, I am deleting the formula.
Shokopuma 20:08, 1 May 2006 (UTC)
thread_title: deleting a formula

message: Vis-à-vis bosonic string theory, the article says the following:
:Most importantly, the theory has a fundamental instability, believed to result in the decay of space-time itself.
I'm not a specialist, so I can only guess that this refers to the existence of a tachyon in the bosonic string spectrum and the fact that D-branes in bosonic string theory are unstable. . . but Dirichlet branes are not spacetime.  Did something get garbled or oversimplified here?  Anville 20:00, 8 June 2006 (UTC)
thread_title:  Questionable sentence in "History" 

message: Someone deleted my previous corrections to the table in the "basic properties" section, I wrote them once again.
The tachyon in bosonic string is an instability, as in any field theory. the nature of this instability is discussed in the previous section.
In type II string theory there are no open strings only perturbatively. However it is well known that these theories do include open strings, attached to D-branes.
For references, see Polchinsky's book ("string theory"), volume 2, chapter 13. Dan Gluck 18:53, 11 June 2006 (UTC)
thread_title:  Table corrected 

message: I tried to shorten this article up and clarify it. This involved moving the section on cosmic strings to the cosmic string page – the debunking of CSL-1 has somewhat damped interest in this topic – and moving the "aspects of quantum field theory section" to its own page, Relationship between string theory and quantum field theory, because I have a hard time seeing how this fit into the main thread of the page (and, quite frankly, I don't agree that many of the topics mentioned are more natural in string theory, and I think it would be hard to find a significant number of string theorists who argue that they are). This page still has problems with the uneven technical level and chatty phrasing. –Joke 03:36, 28 June 2006 (UTC)
thread_title:  recent edits 

message: I removed this text:
:Many researchers at Northeastern University and the University of California say that scientists might soon have evidence for extra dimensions and other exotic predictions of string theory. Early results from a neutrino detector at the South Pole, called AMANDA, show that ghostlike particles from space could serve as probes to a world beyond our familiar three dimensions and one dimension of time.
This is not a solid test of string theory. It is the result of a fanciful press release. Apparently it is quite popular these days to claim that your experiment can test string theory. –Joke 18:13, 12 July 2006 (UTC)
thread_title:  "Evidence of string theory?" section 

message: Added some stuff and:
Corrected some flase statements:
- that the length of a string is a planck length.
Deleted the statement in the remark that "Some string theorists think that this phenomenon prevents the singularities of classical general relativity from forming.". There are many thoughts about how this may happen and this remark is not the place to mention them, nor to mention only one of them.
Deleted the remark that "much progress has been made in the direction" and the ref in the sentence:
" It is not yet known whether string theory will be able to describe a universe with the precise collection of forces and particles that is observed, nor how much freedom to choose those details that the theory will allow, but much progress has been made in this direction.[3]"
because this is not yet a well accepted view or work. It may appear somewhere in the article, not in the overview.  —Preceding unsigned comment added by Dan Gluck (talk • contribs) 
Dan Gluck 19:47, 18 July 2006 (UTC)
thread_title:  Editing the Overview 

message: Although I have not read the entire article, I have one question. Are superstrings replacing quarks, or are they simply the sub-constituents of quarks? Also, does it state in this article that the precise energy content of a superstring is proportional to its (representative) particles' mass? (Given that the frequency of the open [non-graviton] superstring represents the particle type, and energy amplitude is proportional to the particle mass. Of course the energy properties of the superstring depend on its location on the Calibi-Yau shape, manifold if you like) Is this true?  --Dark Observer
"Are superstrings replacing quarks, or are they simply the sub-constituents of quarks?"
I believe the latter of your statement is correct. 67.68.54.24 16:09, 10 September 2006 (UTC)
thread_title: Brief Question

message: Hello,
When I try to edit the "Footnotes" or "References and further reading" I don't get the text displayed in the article webpage, but instead get this:
===Footnotes===

All I'd like to do is correct the spelling of "charateristics" to "characteristics" in footnote 3. Maybe I'm just experiencing a little bug. Can somebody else have a try?
Thanks,
Daniel.
:I've made your change, thanks for pointing it out. This is the new Wikipedia reference system. You have to edit the section that contains the footnoted text – "extra dimensions" in this case – to edit the text of the footnote. –Joke 22:41, 25 August 2006 (UTC)
thread_title:  Can't edit Footnotes Section 

message: I reverted a series of edits made by 198.240.130.75, being uncertain as to their veracity and usefulness. If there are any experts in String Theory around, maybe they can examine these edits more closely and decide what to do. Yandman 14:59, 11 September 2006 (UTC)
replies: text: I'm no expert on string theory, but I know a lot about how physicists talk about things.  This appears to have been written by someone quite knowledgable; so it's very likely to be true.  However, the tone and choice of emphasis may reflect a particular (skeptical) viewpoint; then again, the article may largely have reflected the optimism of string theorists before this (most popular writing on string theory does), so this may bring balance.  Obviously a willingness by the anonymous editor to make comments and discuss the changes would be helpful. -- SCZenz 16:02, 11 September 2006 (UTC)

text: I am something of an expert on string theory, and I can't find too much to complain about in these edits.  (I see that the anonymous user has reinstated them.)  The aren't inaccurate, certainly, and while their POV is at least a little bit "skeptical" it isn't violently so: by and large, they highlight some important disclaimers about the theory.  My main concern is just making sure that they fit with the style and level of the rest of the article (I'll want to look at that paragraph on background dependence more carefully).--Steuard 17:55, 11 September 2006 (UTC)

text: I very much agree with Joshua's comments. –Joke 01:51, 12 September 2006 (UTC)
thread_title:  Edits made on 11th September 

message: A black hole singularity is an infinitesimally small, two dimensional ring that spins at the speed of light and its surface wiggles with quantum foam. Wouldn’t this pretty much describe a closed string as well? Especially since closed strings describe fermions and the shorter the wavelength at which they oscillate, the greater the mass of the particle of matter they represent. Wouldn’t this prove that strings do exist?
:A black hole's singularity is 0-dimensional, and its event horizon is 2-dimensional.  Strings are 1-dimensional.  So there certainly isn't a direct analogy.  Brian Greene does discuss the relationship between strings and black holes in one of the later chapters of The Elegant Universe, though.  (A caveat for my own piece of mind: Mr. Greene is a little bit overenthusiastic about the prospects for proving/solving string theory in the near future.  Regardless of what impression you're left with if you do read his book, nobody has a clue if string theory is real, and there are no clear prospects for resolving the matter anytime soon.)
:In the future, please ask science questions at Wikipedia:Reference desk/Science.  Article talk pages are for discussing changes to the articles only. -- SCZenz 16:10, 12 September 2006 (UTC)
replies: text: That's great, I'm not saying science education is a bad thing, and it's always nice to have people interested in particle physics.  I did, after all, recommend his book for the above question.  At the same time, as someone with some familiarity of the experimental tests we will do in the near future in particle physics, I couldn't recommend his work without the caveat that his work oversimplifies things in favor of making strings seem testable.  If an educated critique of some aspects of his work is "knocking him," and you think it's bad just because you enjoyed the book, I really don't know what I can tell you.  If after reading The Elegant Universe you agree with Greene and are uncomfortable with different views, then I think you may be "for the worse" after all. -- SCZenz 17:39, 14 October 2006 (UTC)
thread_title:  Just a question. 

message: String theory is a model, or a mathematical model, not a conceptual model.
It is unkown whether string theory is mathematically sound. In fact string theory is not fully defined non-perturbatively, so it cannot be mathematically sound, it is not even mathematically defined. Moreover, even algebra isn't "mathematically sound" in the sense that one cannot prove that it does not lead to a contradiction (Goedel's theorems).
String theory has not been experimentally tested at all, hence I deleted "with repeatable results".
Deleted a completely unrelated / false part in the end of "T-duality" subsection. Dan Gluck 10:23, 14 September 2006 (UTC)
thread_title: Made some corrections

message: Note: This article has a small number of in-line citations for an article of its size and currently would not pass criteria 2b.
Members of the Wikipedia:WikiProject Good articles are in the process of doing a re-review of current Good Article listings to ensure compliance with the standards of the Good Article Criteria. (Discussion of the changes and re-review can be found here). A significant change to the GA criteria is the mandatory use of some sort of in-line citation (In accordance to WP:CITE) to be used in order for an article to pass the verification and reference criteria. It is recommended that the article's editors take a look at the inclusion of in-line citations as well as how the article stacks up against the rest of the Good Article criteria. GA reviewers will give you at least a week's time from the date of this notice to work on the in-line citations before doing a full re-review and deciding if the article still merits being considered a Good Article or would need to be de-listed. If you have any questions, please don't hesitate to contact us on the Good Article project talk page or you may contact me personally. On behalf of the Good Articles Project, I want to thank you for all the time and effort that you have put into working on this article and improving the overall quality of the Wikipedia project. Agne 00:54, 26 September 2006 (UTC)
replies: text: Does anyone else have any sort of response to this? I agree there aren't a lot of citations but most statements in this article can be verified in one or two canonical references like Polchinski's book. It doesn't seem to make a lot of sense to refer to the same reference over and over again in the  text. Or maybe I'm missing the point of the complaint. Joshua Davis 06:22, 26 September 2006 (UTC)
replies: text: While a diversification of sources are idle (for cross referencing and so), you can utilize the same source for multiple citations through the article. WP:CITE links to some good info on that. Agne 08:23, 26 September 2006 (UTC)
replies: text: There is also the problem that by using only a very limited number of sources, the sources may be missing something that would be needed for an article to be completely broad on a topic, and people just using those sources might never realize it. Homestarmy 18:23, 26 September 2006 (UTC)
thread_title:  GA Re-Review and In-line citations 

message: I added a section titled "Motivation." I intend to add to it and continue to edit it, but I just wanted to start it and see what kind of feedback I would get from those more experienced with this article than myself, or see what others would have to add.
Mkroh 22:38, 6 October 2006 (UTC)
thread_title: Added Section

message: I've formated the Archive Box into something easier to access opposed to an unformated link.Wikidudeman 22:42, 30 September 2006 (UTC)
thread_title:  Archive Box 

message: Just adding this section title won't help us much. What are you disputing? Awolf002 17:27, 14 October 2006 (UTC)
thread_title: The neutrality of this article is disputed.

message: Added the following sentence to the introduction: The goal is to be able to describe the four forces (strong, gravitational, electromagnetic, and weak) with the same set of equations. Mkroh 00:18, 18 October 2006 (UTC)
thread_title: Added Sentence

message: Is there any information on things that have been proposed as dimensions 5 through 10? I wondered if the five senses could be considered part of those missing dimensions. Does that make any sense? Titan4mmb 03:41, 22 October 2006 (UTC)
replies: text: Sorry, but your idea does not make sense. Extra dimensions are planck-scale (of the order of 10-35m) and curled up into Calabi-Yau spaces, so they have nothing to do with your dimensionless senses. The theory is not mystics. Kurochka 10:33, 22 October 2006 (UTC)
thread_title:  Information on extra dimensions? 

message: I think this new section should be removed. As the title already indicates, and the text clearly shows: This violates WP:NOR. Does anybody have any attribution of this text to a WP:RS? Awolf002 14:47, 5 November 2006 (UTC)
replies: text: Agreed. Joshua Davis 19:46, 5 November 2006 (UTC)
thread_title:  A speculation on the 10 dimensions 

message: I agree with the GA review committee that this article could use more inline references.  It's handy when you come across a bold statement, and your immediate question is, "says who?"  For instance, the idea that anthropic explanations are not considered scientific in the Popperian sense.  First of all, this passage should explain what "the Popperian sense" is, in a few words, and then give a citation to support that claim.  The notion that a few general sources support any unreferenced statements is rather dangerous, as anyone can add any claims to the article at any time.  It's also inconvenient to check those claims.  For example, if there are several books referenced, one might need to read through the entirety of all of them to find the source for a claim, which may or may not even be supported by any of the references.  Connecting statements with specific sources and if applicable, specific page or chapter numbers would be of immense help to fact-checkers and students. -- Beland 01:31, 10 November 2006 (UTC)
replies: text: We should be forgoing original research, which an absence of citations tends to indicate.  The claim that string theory is unfalsifiable is disputed among physicists and philosophers of science, and thus isn't NPOV.  Certainly if string theory predicts electromagnetism, then it is falsifiable, since it would be false if there were no electromagnetism.  And that's just one of many predictions (logical entailments) of string theory. -- Jibal 06:57, 6 March 2007 (UTC)
thread_title:  References and Popper 

message: From "Basic Properties": "Like springs, the strings want to contract to minimize their potential energy" Talk about anthropomorphism! "tend to"? "will, if unconstrained,"? "tend towards a state of minimal potential energy by contracting"? --Hugh7 09:31, 13 December 2006 (UTC)
replies: text: Done Dan Gluck 20:22, 9 April 2007 (UTC)
thread_title: "want to"?

message: "Studies of string theory have revealed that it must never be known by Pete and also predicts not just strings, but also higher-dimensional objects..."
Who/what the heck is pete?
:A bit of minor vandalism.  In that case, it was removed two minutes after it was placed, but it would seem you saw the vandalized version. --TeaDrinker 05:23, 28 December 2006 (UTC)
thread_title: Huh?

message: I don't quite follow where it begins "String theory is like a big tree, being purple and like a kitty Cat with a ball of yarn, and everyone knows there is nothing cuter..." - could someone enlighten me? Is it saying that string theory is ridiculous, or demonstrating all the possibilities of multiple worlds, or what? If so, it is badly worded... Just my contribution.
Parky 23:23, 5 January 2007 (UTC)
replies: text: This was just vandalism which has been corrected Dan Gluck 20:24, 9 April 2007 (UTC)
thread_title: Introduction...

message: I am certainly no expert on string theory, but i play guitar and suspect that a guitar string can only really produce different notes by shortening the string, not by vibrating at different frequencies (wouldnt that just make it softer or louder??). Is the analogy between a guitar string and the particle-string accurate, made on the third line of the first section?24.235.120.106 18:29, 8 January 2007 (UTC)
thread_title:  Analogy with Guitar Strings 

message: I deleted this line: "(Of course, the existence of such a simple test of general relativity rested on the historical accident that the moon and the sun have the same angular size as seen from Earth, allowing total solar eclipses to occur.)"
Primarily, it is incorrect.  The feature of an eclipse required for the testing of the bending of light is that the moon's angular diameter be GREATER THAN or equal to the angular diameter of the sun.  It's not required that the moon and sun have the same apparent angular diameter, only that the sky get dark enough when the sun is up that the stars can  be observed.  Second, since we can do this measurement with radio telescopes even without a total eclipse, the "historical accident" only affected the timing, allowing the confirmation of GR to be done without waiting for radio telescopes to be developed. 
This could be clarified by adding explanations, but why should it be?  The point has nothing to do with string theory.  The article has a link to the solar eclipse page, to allow those interested in it to find that proper information.
Geoffrey.landis 19:41, 18 January 2007 (UTC)
thread_title:  Eclipse 

message: I think it is important to differentiate between standard String Theory and Superstring Theory. I added "This phrase is often used as shorthand for Superstring Theory," but most of the article is discussing Superstring Theory so perhaps the content related to Superstring Theory should be moved to the Superstring article.—The preceding unsigned comment was added by 70.63.79.219 (talk • contribs).
:I thought they were the same thing.Wikidudeman (talk) 04:06, 5 February 2007 (UTC)
thread_title:  String Theory vs. Superstring Theory 

message: After reading an article in Scientific American's website on The Geometer of Particle Physics which refers to the work of mathematician Alain Connes  on noncommutative geometry and renormalization, it appears that a directly testable method is available as an alternative to String Theory.  The article referenced is at .
When the Large Hadron Collider boots this year it will give Connes data to to extend his work to smaller scales.
The point of making this comment is that testable alternative to Sting Theory should at least be presented under an Alternatives to String Theory section, and particularly, Connes work should be referenced and his webpage at Wikipedia elaborated on in light of this promising body of work.
--4.156.144.246 18:46, 6 February 2007 (UTC)
thread_title:  Directly Testable Alternative to String Theory 

message: The overview doesn't cite sources very well, and there are far too many rhetorical questions asked.
--24cell 07:48, 7 February 2007 (UTC)
thread_title:  Overview not up to standard 

message: I need some clarification here. In the last part of the intro., it says, 
Studies of string theory have revealed that it predicts not just strings, but also higher-dimensional objects (branes).
Doesn't string theory assume the existence of objects called strings rather than predict them ? 
Same for branes ? Could someone knowledgeable about these matters clarify this ? Thanks. MP   (talk) 16:34, 7 February 2007 (UTC)
replies: text: Scientific theories make or entail claims about the world -- such claims are predictions, not assumptions.  Suppose that I have a frog theory that posits that there is a frog at the bottom of every well, even those we aren't able to descend.  A prediction of this theory is that one will hear croaking coming out of any well.  Eventually, if we develop the technology to descend down to the bottom of every well, the theory predicts that we will actually find frogs at the bottom of each of them.  At no point is the existence of frogs an assumption of the theory. -- Jibal 07:20, 6 March 2007 (UTC)
replies: text: Branes are a prediction of string theory, not an assumption.  They arise in many ways.  1) If we postulate (assume) strings that have ends, a mathematical transformation called T-duality brings about an equivalent theory with dynamical branes in it.  2) Some string theories have excitations that are a bit like electromagnetism, called Ramond-Ramond fields, which need to be sourced by extended objects, the branes.  There are many, many other ways that branes pop-up.PhysPhD 02:39, 29 March 2007 (UTC)
thread_title:  Clarification 

message: "String theory is a model of fundamental physics whose building blocks are one-dimensional extended objects called strings, rather than the zero-dimensional point particles that form the basis for the Standard Model of particle physics."
What? —The preceding unsigned comment was added by 84.66.228.157 (talk • contribs).
In the standard model, the particles are points. In string theory, they are little lines. Dan Gluck 21:34, 9 April 2007 (UTC)
thread_title:  Thanks for that 

message: Is a 'quantum string' the same as a 'string' (a string in the sense of string theory) ? I think they are the same, but I need some experts to verify this. The article mentions quantum strings, but I don't think it's made clear that these are the same (if they actually are) ? I await clarification. MP   (talk) 17:23, 7 February 2007 (UTC)
replies: text: One can study classical (ie, non-quantum) string theory, and this is generally done as you're learning string theory.  It's (currently) more of a pedagogical tool and toy model, so almost always when people refer to string theory they are referring to the quantum version.  If you want to emphasize aspects of the string that are quantum or non-quantum, you prepend quantum or classical.  That is, the fact that a given string vibrates at a given set of frequencies (harmonics) is a classical property (witness a guitar string), but the fact that a string vibrates only at certain amplitudes is a quantum property.  I should note that many classical properties are inherited by the quantum string -- so a quantum string has both quantized frequencies and quantized amplitudes. 69.143.82.37 17:07, 7 March 2007 (UTC)
thread_title:  Quantum strings ? 

message: I'd like to create a string theory stub. My proposal can be viewed here. MP   (talk) 20:11, 8 February 2007 (UTC)
thread_title:  String theory stub 

message: The subsection on duality is very long. How about we create a new article called String duality to include the bulk of the material in the present subsection and include a main article link to this proposed new article ? Comments appreciated. MP   (talk) 19:49, 9 February 2007 (UTC)
replies: text: I think that would be appropriate given the size and importance of the material. -- Fropuff 19:57, 9 February 2007 (UTC)
replies: text: Done. I have 'created' string duality in the sense that I just copy and pasted the present article's material there and have not removed the material from here. I am not confident of removing the material here and rehashing it into a more concise form, as I don't know enough about the topic. I'll leave that for more knowledgeable editors to deal with. MP   (talk) 20:21, 9 February 2007 (UTC)
thread_title:  New article on String duality ?  

message: Is there too much repetition in the article, for example, in the intro. and the overview ? MP   (talk) 19:00, 10 February 2007 (UTC)
thread_title:  Too much repetitive info. ? 

message: Removing information is vandalism R. Mirman 16:16, 11 February 2007 (UTC)
replies: text: You are mistaken, on this matter and others; removing information is not WP:Vandalism. -- Jibal 07:27, 6 March 2007 (UTC)

text: You've been informed about WP:OR. If you do not begin to comply with Wikipedia process and community standards, you will end up blocked. --Dante Alighieri | Talk 20:09, 11 February 2007 (UTC)

text: Your book (I see it's sold on Amazon) is self-published at vanity press publisher iUniverse. I am unable to find any reviews of your book in Physics journals, nor any papers that you've submitted to peer-reviewed journals. The mere fact that your ideas have been printed is not sufficient... ANYONE can publish ANYTHING. If you can provide references that show your articles have been peer-reviewed or supply reviews of your book(s) by reputable academics, then (AND ONLY THEN) they can be used as sources for the article. --Dante Alighieri | Talk 17:23, 12 February 2007 (UTC)

text: Given your stance on peer-reviewing, I shall assume that you do not plan on offering any journal articles. However, at that same link there are 3 reviews from (presumably) your peers who don't seem much impressed by your post. --Dante Alighieri | Talk 17:31, 12 February 2007 (UTC)
thread_title:  Mirman 

message: What does the first line have to do with anything, is that just vandalism?
:I'm unsure what it is that you saw, as there is nothing in the first line about Asians... nor has there been at any time in the recent history. --Dante Alighieri | Talk 23:48, 12 February 2007 (UTC)
replies: text:  The last version of the 'asian info' in the first line is here. MP   (talk) 16:13, 13 February 2007 (UTC)
replies: text: I stand corrected. I didn't see that diff when I was looking before. Sorry. :) And yes, that was "just" vandalism. --Dante Alighieri | Talk 22:40, 13 February 2007 (UTC)
thread_title: Asians?

message: The end of the first paragraph mentions the 'same set of equations'. Perhaps the link could be sharpened (which is presently very vague for the topic in question) to the actual equations that supposedly unify the 4 forces. Admittedly, this is asking for a lot, but someone out there must know what these equations are. Experts, we need your help !!! MP   (talk) 19:34, 17 February 2007 (UTC)
replies: text: You ARE asking for a lot. Had anybody known what these equations are, he would have gotten a Nobel prize. All that exists currently is either unfinished propositions or equations which consists of much more parameters put by hand than those needed to be predicted. It is possible to put a link to unfinished propositions which give for example gravity and supersymmetric gauge thoery which can be hopefully broken to the standard model, but I'm afraid that putting such a link will encourage people to think that there is a solution to the problem. If anyone is interested, he should better go to the related links in the body of the article.Dan Gluck 19:07, 9 April 2007 (UTC)
replies: text:  The sentence in question has been changed (not sure when and by whom) to include the word 'may' instead of 'appears to be able to'. I am happy with this. MP   (talk) 15:56, 11 April 2007 (UTC)
thread_title:  Where are 'the same set of equations' ? 

message: The article states:
Investigating how a string theory may include fermions in its spectrum led to the invention of supersymmetry, a mathematical relation between bosons and fermions.
Supersymmetry was invented/discovered by Wess and Zumino in context unrelated to string theory.  See the article on Supersymmetry for further references. 69.143.82.37 17:17, 7 March 2007 (UTC)
thread_title:  Supersymmetry and String Theory 

message: I have just removed this dead link from the article: Has string theory tied up better ideas in physics?, Northwest Florida Daily News, 6/23/2006. If someone can find the correct link (if it still exists in some form, then it's still here in the talk page. MP   (talk) 20:13, 7 March 2007 (UTC)
thread_title:  Removed dead link 

message: I don't think the section on extra dimensions is correct, and, at a minimum, there certainly there isn't a citation around the relevant passages.
There are:
One intriguing feature of string theory is that it predicts the possible number of dimensions in the universe. . . .
Unlike general relativity, string theory allows one to compute the number of spacetime dimensions from first principles.
I don't think that's right at all.  Extra dimensions are assumptions of string theory, and the number of dimensions were selected to conform the theory to the observed behavior of particles.  That isn't a "prediction," and the number of dimensions is not being "computed" from "first principles," dimensions are being added to make the theory work with experimental results.  
And isn't there still some question about whether the ten-dimensional theories are really eleven dimensional ones?208.226.153.24 18:11, 5 April 2007 (UTC)
replies: text: You are totally wrong. Superstring theory is based on a two-dimensional quantum supergravity with weyl invariance in 2 dimensions - this is the theory on the worldsheet. The weyl invariance is gauged, and is anomalous unless the number of space-time dimensions is 10 (in a Lorentz-invariant theory).In strong coupling, a certain version of string theory (called type IIA) is better expressed at low energies in terms of a 11-dimensional theory coined M-theory. All this is explained in the article.Dan Gluck 18:42, 9 April 2007 (UTC)

text: The most accurate statement would be, that superstring theory is consistent only in 10 dimensions (if we ignore for a moment the non-critical string). Therefore it is not correct to say that this number is selected "to conform the theory to the observed behaviour of particle". The term usually used is "predicts", because if one takes the fundamental assumptions of string theory then this number can actually be computed, but I added a clarifying sentence in order to make this more accurate. Dan Gluck 19:19, 12 April 2007 (UTC)
thread_title:  Predicted extra dimensions 

message: I changed a paragraph the introduction to reflect the ongoing debate on the predictability of string theory.
I created in the introduction a paragraph about string theory as a possible theory for the strong interactions (thorough gauge-gravity duality), because although the math is identical, it is a theory of totally different phenomena than quantum gravity.
There was a link in the introduction about AdS-CFT RHIC-related stuff. This was a non-scientific media report, and the link was in the wrong context - suggesting that success in predicting stuff at RHIC is related to string theory as a theory of quantum gravity. I changed the link to few links to the related scientific papers and placed it in a paragraph of a correct context - the new paragraph in the introduction about gauge-gravity duality.
In the "problems and controversy" section, I added a paragraph about the "string wars" - the 2 new books by Woit and Smolin and the discussion that followed. I incorporated into this paragraph the quote by Smolin which has previously been put out of any context, and added the infamous "only game in town" answer for balance - perhaps both quotes should be omitted? —The preceding unsigned comment was added by Dan Gluck (talk • contribs) 18:52, 9 April 2007 (UTC)
thread_title:  Last Edit

message: String theory is an interesting way of combining quantum mechanics and Einsteinian relativity. However string theory, in my opinion, hasn't given any major predictions about the universe and the way it functions.  Does string theory actually tell us anything about the universe that we didn't already know? Wikiisawesome 11:41, 11 April 2007 (UTC)
replies: text: These are all good points which I think are addressed to some extent in the text, particularly in "Problems and Controversy". Feel free to clarify the article yourself, though, if you feel it is necessary. --Joshua Davis 17:30, 18 July 2007 (UTC)
replies: text:  Point 2 would be nice, but we can't insist upon it.  The distance from the earth to the sun might have been thought of as such a parameter, but of course it's value is a function of the complicated history of the universe, not just the theory governing its dynamics.  Similarly, the charge of the electron may turn out to be incalculable from first principles, due instead to the complicated dynamics of a modular field that happened to settle down to a particular value in the visible universe.PhysPhD 18:26, 18 July 2007 (UTC)

text: String theory can be a theory but yet not a Theory of Everything. One option to which PhysPhD implies is that additional ingredients such as the anthropic principle should also be considered. Another option, for example, discussed recently by David Gross, is that string theory is a framework, like quantum field theory: due to its huge number of solutions, it cannot predict things such as the number of non-compact dimensions (your no. 3) or coupling constants (your no. 2), but given a solution (our place in the anthropic landscape), we can in principle calculate. This is similar to quantum field theory because quantum field theory per se does not predict which fields there are and what are the gauge groups or coupling constants, but given these it gives us tools to calculate, and furthermore it imposes constraints on the fields and possible couplings (for example gauge anomalies must cancel, CPT invariance must hold, etc.). Just to remind you, quantum field theory is the cornerstone of modern particle physics and has been checked experimentally to great accuracy. The big problem with string theory remains contact with experiment (your no. 1). I hope the article is clear enough about it. Personally I don't believe this problem will be overcome in our lifetime (or at all), but there's no consensus regarding that point. Dan Gluck 19:36, 18 July 2007 (UTC)

text: You are assuming that, basically, if it was true, we would know it right away because the problems would sort themselves out? This makes little to no sense at all! The fact that we are this far scientifically is astounding. Although you do raise good points about whether we should've known the answers right away, the fact remains; algebra does not solve itself, rocket science does not solve itself... altogether, no problem solves itself. Why should something deemed so unachievable not be difficult to uncover? What gives humankind the right to uncover it in the first place? Conclusion: if you are going to say that string theory should be easy to understand, think about it for a minute and you'll realize that string theory is uncovering one of the greatest finds since discovering that the earth is not flat. It's a breakthrough and will take time to prove. Musicnotz (talk) 17:32, 29 July 2008 (UTC)
thread_title:  Problems with String Theory 

message: Is it worth creating a second page with a more technical intro to string theory, more like a lot of math pages that aren't affraid of including equations?  If people think this is a good idea, someone who knows how could create the page and I could start filling it in...PhysPhD 04:27, 13 April 2007 (UTC)
replies: text: There's a couple ways of approaching it. One could try to keep this article as accessible as possible putting the technical details into more specific articles like superstring theory, bosonic string theory, type II string theory, etc. The other alternative (and a seemingly acceptable common practice) would be to put the nontechnical overview at Introduction to string theory and keep the technical information here. See for example: introduction to general relativity and introduction to quantum mechanics. -- Fropuff 05:21, 13 April 2007 (UTC)
replies: text:  I prefer the first alternative, but though I can do it in principle, it's a lot of work... Dan Gluck 18:38, 13 April 2007 (UTC)
thread_title: Technical Page?

message: New, interesting, preprints are popping up every day on arXiv and are discussed on the relevant blogs. But this here aims at being an encyclopedic article, doucumenting established knowledge. So can we pls wait adding new stuff until it has evolved to a review article written by a respected author, or something similar? --Pjacobi 12:16, 21 April 2007 (UTC)
replies: text: What is the context of your remark? Dan Gluck 11:05, 22 April 2007 (UTC)
replies: text:  http://en.wikipedia.org/w/index.php?title=String_theory&diff=prev&oldid=124587390 and most other arXiv-Link-insertions. --Pjacobi 15:35, 23 April 2007 (UTC)
thread_title:  Some restraint in adding preprints 

message: Hey everyone. If you like being confused by this stuff, go to 
www.tenthdimension.com
and watch the video, "Imagining the Ten Dimensions" under the "Navigation" bar.
It's really cool and kinda confusing, but cool and fun to watch. —The preceding unsigned comment was added by Tidman5 (talk • contribs) 17:46, 24 April 2007 (UTC)
replies: text: This video is totally unscientific nonsense (at least from 5 dimensions and up) and has nothing to do with string theory Dan Gluck 19:42, 30 April 2007 (UTC)

text: Agreed; this video is more philosophical and is, in fact, jargon. It makes little to no sense as it is only about trying to explain the unexplainable, and, while entertaining, is unscientific. It has absolutely nothing to do with string theory. Musicnotz (talk) 17:26, 29 July 2008 (UTC)
thread_title:  Website about String Theory and the 10 Dimensions. 

message: This seems like major news which should be reported within the article:
:...Princeton researchers have found new mathematical evidence that some of string theory's predictions mesh closely with those of a well-respected body of physics called "gauge theory," which has been demonstrated to underlie the interactions among quarks and gluons, the vanishingly small objects that combine to form protons, neutrons and other, more exotic subatomic particles. The discovery, say the physicists, could open up a host of uses for string theory in attacking practical physics problems....
:...The team's paper appears in the March 30 issue of the scientific journal Physical Review Letters. Klebanov's co-authors include graduate student Marcus Benna and postdoctoral fellows Sergio Benvenuti and Antonello Scardicchio. 
:...In the 1970s, physicists posited that when gauge theory loses its power to describe particle behavior as quarks bond together, string theory might be able to step in and handle the job. What string theorists needed was some indication that both theories were headed in the same direction.  The lucky break came in 1997 and early 1998 when a precise relation between the two was conjectured in the work of Princeton physicists Alexander Polyakov, Steven Gubser and Klebanov, as well as the Institute for Advanced Study's Juan Maldacena and Edward Witten....
:...String theory, for all its mathematical beauty, once again seemed too difficult to test -- until Niklas Beisert, an assistant professor of physics at Princeton, published a paper in late October of last year containing an equation that turned out to be a crucial piece of the puzzle.  "Beisert and his collaborators made an inspired guess based on sophisticated notions of gauge theory behaviour," said Curtis Callan, the James S. McDonnell Distinguished University Professor of Physics at Princeton. "Their equation allowed Igor and his colleagues to work out the 'transition' between the two regimes. They demonstrated that it exactly matched string theory's predictions at the strong interaction limit....
See these websites
RK
: NO, NO, NO. This is yet another confirmation of the AdS/CFT correspondence, the best known example of the gauge-gravity duality conjecture. Unfortunately the reporter didn't understand what's going on. Dan Gluck 13:43, 24 May 2007 (UTC)
thread_title:  Princeton physicists connect string theory with established physics 

message: how can string theory be proven? I've never actally seen it work...
: Do you mean mathematically, or to test it in nature? Mathematically it can only be show to be consistent, either by its own or also with quantum field theory and gravity. This is thought to be correct, but a real proof will probably not be seen in the near future. The Testability of the theory is a big problem, which is addressed in the article. Dan Gluck 13:45, 24 May 2007 (UTC)
thread_title:  Uhhhh... Wow. 

message: I just - somewhat bluntly - reverted an edit that painted a very rosy picture of the prospects of experimental verification of string theory, claiming the optimism to better reflect the "expert" consensus.  The consensus among basically every other string theorist I know (including one of the people behind the work at Princeton alluded to above) is that it is very unlikely we would have confirmation of s.t. as a theory of gravity any time soon.  There are some scenarios where it could amazingly appear at the LHC, but this is just what people talk about to get grant money.  People who believe in string theory (such as myself) just don't expect to see it there.  The problem is that the Planck scale, where quantum gravitational effects are believed to become significant, is like 15 orders of magnitude higher than the energies produced at cern.  Some phenomenological theories (eg ADD) would move the scale way down, but most think it would take a stroke of blind luck if these theories are realized.  Assuming the Planck scale is where most people think it is, no theory of quantum gravity (not string theory, not Smolin's loop quantum gravity...) is going to be tested at the LHC.PhysPhD 06:13, 27 May 2007 (UTC)
thread_title:  Testing String Theory 

message: This sentence contains an alleged direct quote that appears in a publisher's blurb as if it is a paraphrase (that is, not in quotes):
*  "String theory —the hot topic in physics for the past 20 years—is a dead-end," says Smolin, one of the founders of Canada's Perimeter Institute of Theoretical Physics and himself a lapsed string theorist .
A quote from Smolin may be good here, but unless the above can be verified as his actual words, someone needs to find another one. I've removed the sentence.
:I removed the "only game in town" quotation (which I originally put as a counterbalance to Smolin's quotation), for the same reason, as well as for the sake of preserving neutrality. Dan Gluck 08:49, 7 June 2007 (UTC)
thread_title:  Removed an apparently incorrect quotation 

message: This quote was removed from the article:
:"String theory —the hot topic in physics for the past 20 years—is a dead-end," says Smolin, one of the founders of Canada's Perimeter Institute of Theoretical Physics and himself a lapsed string theorist . 
A quick Google search will reveal that this is from the Publishers Weekly review of The Trouble With Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next by the named author.  I have no particular opinion about whether the quote, properly cited, should return to the article.
CRGreathouse (t | c) 12:28, 7 June 2007 (UTC)
thread_title:  Removed quote 

message: The following invisible remark has been added to gauge-gravity duality section:  What is the meaning of this? Dan Gluck 17:28, 26 June 2007 (UTC)
thread_title: What is the meaning of the remark?

message: I have deleted a link to an animation taken from the pseudoscientific "the tenth dimension" book and website, which has nothing to do with string theory's interpretation of this concept. Dan Gluck 14:29, 4 July 2007 (UTC)
thread_title:  link to pseudoscientific explanation deleted 

message: I added a Preface right before the Overview section...
I think it's important for the readers to know that an article could be endless if it highlighted all the possibilities that string theory says could happen, and that the information presented is going to highlight one of the many "versions" of String Theory.
Feel free to edit the preface, but after hearing many documentaries on it (many of which conflicted with each other) it's good to know that the information you read isn't always the ONLY way string theory could work. --Huper Phuff talk 21:45, 12 July 2007 (UTC)
replies: text: Edit: I noticed there is a part in the intro that talks about the different versions of String Theory, so the Preface might be up for debate...I say it's still necessary... --Huper Phuff talk 21:45, 12 July 2007 (UTC)
replies: text: The article covers these issues, so there's no need for this awkward disclaimer.PhysPhD 22:56, 12 July 2007 (UTC)
replies: text: There is something which SHOULD be added, and I think the overview is the place: That's explaning that string theory can be approached either by using worldsheet tools or by using supergravity tools, and that the two approaches are complementary. The article puts emphasize mainly on the first approach (partly I'm the one to blame for that). I intend to edit the overview in that spirit. Dan Gluck 06:41, 13 July 2007 (UTC)
thread_title:  Preface 

message: There was a sentence that I have deleted which stated that String Theory was at this point, a mere philosophy since it has not made any falsifiable prediction. This is an extreme POV since String Theory is not just some random philosophical speculation but a mathematically consisitent model that has compelling features to be considered as a contender for the Theory of Everything —Preceding unsigned comment added by 220.227.207.36 (talk) 
:I agree. Certainly it is not a philosophy since it has a mathematical structure. At most one may say it's mathematics rather than physics, but that's a matter of POV as well. Dan Gluck 14:00, 24 July 2007 (UTC)
replies: text: The reason it is stated as a philosophy, "religion", belief or w/e...is because the field of science is about studying the physicaly world and making theories that fit this "idea" of the world that can be proved through experiments and/or testing. Since string theory, as of yet, cannot be proved it has a very careful placement. If you can never prove something, then it merely becomes a personal belief, however there are ideas on how string theory can be proved so it does have some scientific application (also because it can be proved mathematically). That why it is appropriately named string THEORY. For example: if you say the universe is infinite, because string theory predicts it...there's no way of proving that the universe is inifinite so it merely a personal belief. --Huper Phuff talk 21:07, 29 July 2007 (UTC)
replies: text: Hi Huperphuff. I totally agree with you. However the term "philosophy" is not accurate, because a philosophy has no coherent mathematical structure. Furthermore, string theory has a huge contribution to mathematics. However, it cannot be considered as mathematics, since it lacks the rigour needed for that. It is sometimes called "methametical physics", though in my point of view it should more properly be called "physical mathematics" or, more properly, "non-rigourous mathematical structure". Anyway, it is a matter of POV how to call it, and there is certainly no concensus that it should be called "philosophy", just as there is no concensus that it will never make contact with experiment, so your sentence violates WP:POV, just as would be a sentence calling it "non-rigourous mathematical structure", which I believe it is. Dan Gluck 18:26, 30 July 2007 (UTC)
thread_title:  Removed Line  

message: Why did you delete the  nice analogy "just as a guitar string can produce different notes"? I returned it. Dan Gluck 09:03, 24 September 2007 (UTC)
replies: text: String theory is special in that its mathematics is virtually all modern mathematics, excluding much of discrete mathematics. So you're asking for too much, However, for the most basic concepts, you may look at vibrating string, then standing wave and wave. For more, you should just go to the relevant physical field and read - classical mechanics, electromagnetism, quantum mechanics, special relativity, general relativity... that's already a very long list. It took me 12 years to learn all this. Good luck. Dan Gluck 18:36, 12 November 2007 (UTC)
thread_title:  guitar string analogy 

message: I've ported a diagram presenting the level of strings in comparison to other entities (molecules, subatomic particles) from the French Wikipedia. The caption has been directly translated from French.  —Preceding unsigned comment added by 203.28.13.57 (talk) 03:08, 20 November 2007 (UTC)
thread_title:  Added diagram 

message: In fact, Kaluza and Klein's early work demonstrated that general relativity with five large dimensions and one small dimension actually predicts the existence of electromagnetism.
Five large and one small, or five total (four large and one small)? 72.75.125.22 (talk) 02:21, 25 January 2008 (UTC)
replies: text: It is five total. I have fixed the article. Joshua Davis (talk) 17:54, 25 January 2008 (UTC)

text: Actually it is just doing General Relativity in 5 dimensions that one can show it can be decomposed into a 4 dimensional General Relativity together with an Electromagnetism.  The large and small dimension thing just comes from an ad hoc attempt to account for the fact that we don't observe 5 dimensions.67.160.131.142 (talk) 04:30, 20 October 2008 (UTC)
thread_title:  Kaluza-Klein 

message: Why is this article tagged? This article does NOT have too much jargon. I think that it was tagged by someone who didn't want to take time to read the whole article thoroughly. I am in the 7th grade, and I don't understand physics, but I understood THIS article enough to write a paper on the string theory! If you need an article that uses simple words and concepts, then use Simple English.--Princess Janay (talk) 17:58, 27 February 2008 (UTC)
replies: text: I removed a  but it was restored with a comment that its removal was "vandalism". Are we going to dumb down this article by stripping it of its "jargon"? I have been working on the stack of prerequisites for this subject and created Template:Theory of everything. If you do not know the significance of, say, general relativity or Planck's constant, then you are not going to understand the significance of string theory. Are we going to dumb down this article the level of the three-hour show The Elegant Universe? Why not just face that if you do not have a good grasp of the math in quantum field theory, e.g. if you do not know what the Klein-Gordon equation means, then you are not going to be able to distinguish string theory from science fiction and you should either learn the math or go entertain yourself with the fiction.--Truthnlove (talk) 12:32, 2 March 2008 (UTC)
thread_title:  Too much jargon? 

message: I couldn't see any section in the article discussion the relationship between the String Theory and the Unified Field Theory. Should we include such a section into the article?
--Mhsb (talk) 22:01, 28 February 2008 (UTC)
thread_title:  Unified Field Theory 

message: In the Principia Newton defined time and space for physics:
I.  Absolute, true, and mathematical time, of itself, and from its own
nature, flows equably without relation to anything external, and by
another name is called duration:
relative, apparent, and common time, is some sensible and external
(whether accurate or unequable) measure of duration by the means of
motion, which is commonly used instead of true time; such as an hour,
a day, a month, a year.
II. Absolute space, in its own nature, without relation to anything
external, remains always similar and immovable.
Relative space is some movable dimension or measure of the absolute
spaces; which our senses determine by its position to bodies; and
which is commonly taken for immovable space; such is the dimension of
a subterraneous, an aerial, or celestial space, determined by its
position in respect of the earth.
We all know that Einstein had something to say on this topic.
He writes in Relativity Chapter 9:
Now before the advent of the theory of relativity it had always
tacitly been assumed in physics that the statement of time had an
absolute significance, i.e. that it is independent of the state of
motion of the body of reference. But we have just seen that this
assumption is incompatible with the most natural definition of
simultaneity; if we discard this assumption, then the conflict between
the law of the propagation of light in vacuo and the principle of
relativity (developed in Section VII) disappears."
The reason for the assumption could be Newton's description of
absolute time being mathematical rather than relative time.
In Chapter 8, Einstein gives his working definition for time:
Under these conditions we understand by the 'time' of an event the
reading (position of the hands) of that one of these clocks which is
in the immediate vicinity (in space) of the event
Einstein is defining time in terms of the moving hands of a clock,
which is nearly identical to how Newton defined relative time:
Relative, apparent, and common time, is some sensible and external
(whether accurate or unequable) measure of duration by the means of
motion, which is commonly used instead of true time; such as an hour,
a day, a month, a year.
While I often hear some claim "Einstein has shown that time is
relative", really, all that he has shown is that our present
mathematics represent relative time, contrary to Newton's definition.
In fact, Einstein had made this point to Heisenberg, I think
demonstrating how easily this subtle point is missed:
"But you don't seriously believe," Einstein protested, "that none but
observable magnitudes must go into a physical theory?"
"Isn't that precisely what you have done with relativity?" I asked in
some surprise. "After all, you did stress the fact that it is
impermissible to speak of absolute time, simply because absolute time
cannot be observed; that only clock readings, be it in the moving
reference system or the system at rest, are relevant to the
determination of time."
"Possibly I did use this kind of reasoning," Einstein admitted, "but
it is nonsense all the same. Perhaps I could put it more
diplomatically by saying that it may be heuristically useful to keep
in mind what one has actually observed. But on principle, it is quite
wrong to try founding a theory on observable magnitudes alone. In
reality, the very opposite happens. It is the theory which decides
what we can observe."
(In 'Physics and Beyond - Encounters and Conversations', Harper
Torchbooks, 1972, p. 63.)
To summarize all that: in the eyes of both Newton and Einstein, while
absolute space and time are "somewhere out there"; it is relative
space and time that we measure..
Emphasis: RELATIVE SPACE AND TIME ARE MEASURED.
Now.
String theory.
There are visible dimensions of space and time, and there are hidden
dimensions.
These hidden dimensions, cannot be measured.
Is there an opinion in the field regarding whether or not these extra dimensions are a "new" type of relative space?
Or is it absolute space? MobyDikc (talk) 06:34, 29 February 2008 (UTC)
thread_title:  Opinion on "relative-ness" of extra dimensions? 

message: I am not an expert on string theory by any means, but i have a basic understanding, whist on the Primordial black holes wikipage i noted that it mentioned some work on trying to find black holes that are predicted by string theory which would be the "could be the first indirect evidence for primordial black holes and string theory.". 
Interested i came to the string theory wikipage to find out about any more projects aiming to do similar things but could not find any. 
A section dealing with these kind of experiments/projects/whatever that attempt to do this (even if its just links to other wikipages) could be quite useful and improve the article somewhat. gord (talk) 01:07, 21 March 2008 (UTC)
thread_title:  Current/planned projects to find evidence of string theory section? 

message: In the first line of 'Overveiw' it says: "Matter is composed of atoms, which in turn are made from quarks and electrons." Atoms are not made of quarks and electrons. this should say: "Matter is composed of atoms, which in turn are made of protons, neutrons, and electrons." Going on to state that protons and neutrons are made of quarks, leptons, and gluons should also be considered, but i don't think it's necessary.
Oh no! I've messed up the discussion page. I'm sorry. I deleted the last post and replaced it with mine.
Minduser  01:22, 18 April 2008 (UTC)
thread_title:  Description of an atom wrong 

message: While string perturbation theory suggested that spacetime was ten dimensional, string theory is just a limit of a non-perturbative theory which is fully eleven dimensional, and is only string-like when one of the dimensions is curled up. To say that string space-time is ten dimensional is so totally eighties.Likebox (talk) 01:02, 2 May 2008 (UTC)
thread_title:  Ten vs. Eleven 

message: I edited the section on compact dimensions to mention structure. The article said the compact dimensions must have holonomy of SU(3) or G2. This is wrong. They must have SU(3) or G2 structure which is basically including torsion. SU(3) holonomy assumes no torsion because it assumes the background NS-NS 3-form flux H3 is turned off. While this is true in the simplest cases, flux compactification is specifically making use of the non-zero H3 flux (along with things like the RR F terms and fluxs created by T duality from H3). Papers often assume SU(3) holonomy despite turning on H3, but again, it's an approximation. Considerable work is being done in the area of full SU(3) structure. See publications by Palti and de Carlos for the differential geometry approach and work by Wecht, Ihl and Shelton in terms of fluxs being turned on and their effect on orientifold model. While I'm not as up to speed for M theory models (non-geometric fluxs in IIB is my thing), a quick look through the thesis of Palti mentions G structure again, which is the M theory version of SU(3) structure. Hence I think it's important not to say "must have holonomy" and to mention the difference. If specific citations are needed, I can provide them AlphaNumeric (talk) 19:52, 20 June 2008 (UTC)
thread_title:  Compact dimensions : Structure vs Holonomy 

message: Please comment on the new image on the progression from macroscopic objects to strings. Dhatfield (talk) 12:13, 27 June 2008 (UTC)
thread_title:  New image 

message: The usage of "p-brane" and "D-brane" without stating that they are black holes in the classical limit makes them seem more mysterious than they are. They are not just surfaces, like topological domain walls in a field theory, they are gravitational objects. The metric for a p-brane is a higher dimensional charged black hole solution extended in the world-volume dimension, and sometimes with a long-ranged scalar field contribution. They are higher dimensional extremal charged black holes, and I believe they were originally defined this way in the supergravity literature (I didn't read the original p-brane papers--- someone who has please correct me).
D-branes are superficially different--- they are endpoints for strings--- but it was Polchinski's great insight that the D-brane should be identified with the p-brane at weak string coupling. In other words, the D-brane is just a p-brane, or what's left of it in limits where strings become perturbative. Unfortunately there is conflicting terminology. Some people call any extended object a "brane", using it as short for membrane, not restricting the usage to those objects which are an extended black hole solution in the classical limit. As far as I know, this is not the terminology that has become standard. If it's not a black hole, just an extended defect, most people (as far as I know) still call it a "domain sheet" or "domain wall" or "topological defect" or whatnot.
Howver in the literature on Randall Sundrum style models, the two concepts of "brane" and "sheet" are blurred. I believe that the reason is that the Randall Sundrum models are sometimes very phenomenological, and don't have to be completely precise about what the branes exactly are as fundamental string theory constructs. So the Randall Sundrum "branes" are not always branes. But I think that this article should stick to the terminology used here, because I think it makes things clearer. Just my 2c.Likebox (talk) 21:30, 2 September 2008 (UTC)
thread_title:  On Terminology 

message: To avoid saying clearly, point blank, that D-branes are quantum versions of charged black holes makes it difficult for people to appreciate the logical coherence of string theory, and leads them to think that it is just guesswork. This is unfortunate, because it makes many people view the whole field with much more skepticism than it deserves. The string theory identification of matter and black-hole, resulting in a precise holographic description of both, is, in my opinion, the greatest achievement of science. But for some reason, people always tiptoe around saying this clearly. I tried to fix that here, but the weasel-words return.
For example--- D-branes are "extended objects which source a differential form vector potential" sounds much more mysterious than "D-branes are extended quantum-mechanical charged black holes". "D-branes are identified with black-hole like p-branes through AdS/CFT correspondence" sounds much more daunting than "when a bunch of D-branes are stacked up one on top of the other, they become classical charged black hole sheets, while the behavior of nearby objects is still described by a theory of the oscillations of the surface". Which is nearly the same statement.
To be fair, there are a few differences between the mental image conjured up by the words "black hole" and the mental image of D-branes. Black holes are classical, and the D-brane is quantum. Black holes are usually imagined to be neutral and thermal, while D-branes are extremal-charged and so non-thermal. Black holes are usually imagined as spherical in four dimensions, while branes are extended in higher dimensions. But that's the end of the list of differences. So to say "A D-brane is like a black hole" is too careful--- it's like saying "an electron in field theory resembles a negative point charge" or "an atom is similar to an electron orbiting a nucleus". We don't say those things anymore, we say "an electron is a point charge" and "and atom is an electron orbiting a nucleus", because the fact that they are quantum mechanical, so that the classical description is not completely correct, goes without saying. As far as authorities go, Witten said it in 1996, before AdS/CFT, and he's the most authoritative authority there is.Likebox (talk) 22:46, 7 September 2008 (UTC)
thread_title:  Weaseling 

message: M-theory has a simplified version. Why can't we have one for string theory? It would help quite a few people understand the concept better, which many would like. 
Thank you for considering the idea.
Lunakeet 13:55, 18 October 2008 (UTC)
thread_title:  Simplified version? 

message: I remember vaguely that Einstein at one point introduced a non-symmetric metric tensor for unification purposes. This is vaguely reminiscent of the way that you get a two form in string theory, it enters like an antisymmetric part of the metric tensor. Since this two form is fundamental--- it is the field of the charge carried by the string--- I thought it might be nice to make the connection, even though I think it is nearly certain that there was no historical connection between these two ideas.
On the other hand, I haven't read Einstein's unified field theory papers (very few people have) and I am not sure if the antisymmetric tensor he played around with is at all similar to the 2-form field. I was hoping somebody would know.Likebox (talk) 19:46, 9 November 2008 (UTC)
thread_title:  Nonsymmetric Tensor 

message: The first line of the table under the String_theory#Dualities section says: "Only bosons, no fermions, meaning only forces, no matter, with both open and closed strings; major flaw: a particle with imaginary mass, called the tachyon, representing an instability in the theory."
So does the tachyon have an imaginary number value for mass under string theory, or is it some other interpretation of the word "imaginary"? I don't know enough about the subject, so I'll leave this change to somebody else. FFLaguna (talk) 06:43, 14 December 2008 (UTC)
thread_title:  Tachyon has "imaginary" mass, or "negative" mass, or something else altogether? 

message: if the string frecuency is the diffrent between subatomic particle so in theory there is an infinet kinds of subatomic particles am i right?--אזרח תמים (talk) 11:22, 28 December 2008 (UTC)
replies: text:  Yes, there are, higher frequency vibrations make infinitely many higher mass particles. but the only subatomic particles we can see are the ones with zero mass, and there are only a finite number of those.Likebox (talk) 19:48, 28 December 2008 (UTC)
thread_title:  subatomic level