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How many?

  1. Jun 4, 2005 #1
    I'm obviously not going to ask how many strings there are in the universe. :wink:
    my question. To each quark how many strings are there? Just one unique one? Billions and Billions?

    Also
    does Brian Greene's book.
    "The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory"
    http://www.amazon.ca/exec/obidos/AS...12351/sr=1-1/ref=sr_1_3_1/701-7083922-2122741
    have the math and equations and such in the book?

    Like does it explain with the math how come there has to be more then 3-4 diimensions and stuff like that?
     
    Last edited: Jun 4, 2005
  2. jcsd
  3. Jun 5, 2005 #2
    Hi Munk

    Nobody seems to have an answer for your first question. That may be because nobody seems to have an answer for your first question.

    Greene's book is mostly not very mathematical, but is written for a general public. I was not satisfied that the question of many dimensions was sufficiently answered in Greene's book, but perhaps you can get more out of it than I could.

    I myself have almost stopped looking for answers to these questions. Instead I have been looking for better questions. There is a lot to learn. I suggest you concentrate on learning the maths, and pay close attention to what the experimentalists are doing.

    Good hunting.

    Richard
     
  4. Jun 5, 2005 #3
    thanks for a response. I guess I'll shoot over to the university bookstore and see if they have any textbooks for the math behind it.

    I find the philosophy part of their interpretations interesting and completely plausible. However I wish to see the math behind it. See if I can understand how they came to those interpretations. So until then it is all philosophy to me. For it to become science to me; I would like to see the math behind it.

    Like as it stands I haven't really seen any math to back up the unfalsifiable claims. So as it stands TOE is as good as say faith-healing or alien abductions. But at least it has math behind it yet to be researched.

    I'm glad I asked about Greene's book. If it ended up just being the interpretations of the math I would have been sad.

    I seen an hour or whatever on the elegant universe where he talks about more dimensions. I must say it really isn't that great. Michio Kaku did a show at infidelguy.com and talked in alot more detail about the dimensions and other universes.
     
  5. Jun 5, 2005 #4

    selfAdjoint

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    The problem with answering "how many strings per quark?" is that there are many attempts to derive Standard Model physics form strings, and they differ in detail, and none of them is final. So this answer is just based on the class of models discussed in Zwiebach's book. One quark is produced by one string; the "color charge" of the quark is determined by the branes the string ends on - there being three branes with charges, one corresponding to each color. This implies to me that when the strong force (carried by the gluons - presumably more strings ) changes the color of the quark, which happens all the time, the corresponding string is freed and rehooked, or perhaps the original string dies and a new one comes into play. This is vague and the trouble with all of these models is that you can't push them much further; they don't do the individual dynamics. This is why none of these models answers the criticism that string physics doesn't predict anything that is observable.
     
  6. Jun 6, 2005 #5

    ohwilleke

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    If string theory is right, the place to begin is either "one" or "more than one". If more than one, quarks (and possibly other "fundamental particles") are really composite and you have a preon model. If one, than you have to have some pretty complex dynamics in each string to create 36 kinds of quarks, six kinds of electrons, and so on. This seems a lot to ask of fundamental entities that are allegedly as simple as it gets.

    In contrast, with some manner of preon type model, you could get down to two to six dynamical modes in a string, with everything else being a composite particle.
     
  7. Jun 6, 2005 #6
    actually thats why i want to see the math behind it. Like why so many dimensions? I think that they are assuming 1 string per quark.

    How do you differentiate between the strings that make unique quarks? The way the string "wiggles"

    To make say one of the electrons it wiggles on in the X plane. To make another quark it wiggles only in the y plane. and so on and so on. I'm kinda rusty with combinatorics but you should have ALOT!!! of unique values that can be used for the quarks that are in 11 dimensions.
    I dunno what all the dimension's letters. Lets just say:
    x,y,z,a,b,c,d,e,f,g,h,i

    so you have 11 unique single ones. then LOTS of doubles. Which i think is 11nPr2 thats 110 unique ways. I think; my calculator on windows doesn't have the function so not exactly positive.

    I really don't have a clue what a brane is. Greene made it seem like a brane is gigantic. Like numerous universes can like on a brane. So I dunno. Little lost there. Sounds this Zwiebach's model has branes being tiny. Which I can understand. I don't have a clue where these giant branes came from.
     
  8. Jun 6, 2005 #7

    ohwilleke

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    Branes are relatively recent compared to string theory generally. Among the virtues of brane theory is that is most family interactings and particles are confined to a brane, then it provides a device for "taming" extra dimensions and explaining why gravity appears so weak (gravitons can leave the brane while many other interacting force carriers cannot).
     
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