Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

A Naive String Theory Question on 10 Dimensions and Poincare Transformation

  1. Feb 28, 2005 #1
    I do not know much about string theory, but the fact that it involves 10 or 11 dimensions.

    I am curious whether this 10 or 11 dimensions of string theory has anything to do with inhomogenous lorentz transformation?.

    [from Goldstein - section 7-2]

    In essence a poincare transformation or inhomogenous lorentz transformation (L) between two frames of reference is

    x' = (RP)x + a

    P -> Pure Lorentz Transformation
    R -> Spatial Rotation
    a -> arbitrary translation vector

    where x and x' are four dimensional vectors.


    P -> beta (v/c) (3 indpendent qtys)
    R -> The spatial rotation - euler angles (3 independent qtys)
    a -> The initial separation of origins!! of frames of references (4 independent qtys)

    totalling 10 independent qtys.

    Does this have anything to do with string theory's 10 or 11 dimension?

    Let me include the one dimension for the string , which is the 11th dimension. I do that as the above transformations where for point (zero dimension) particle based systems.

    Now whatever I have said is just total imagination on my part (no physics) in trying to connect 2 unrelated stuff and might be just total bull****, but I was just curious whether they both do have any kind of connection?

    String theorists, please throw some light on whether this connection is just a coincidence or does it have any real significance?
  2. jcsd
  3. Feb 28, 2005 #2


    User Avatar
    Staff Emeritus
    Gold Member
    Dearly Missed

    No. The ten parameters you cite have nothing to do with the extra dimensions of string physics, which consist of six or seven additional space dimensions in addition to the 1 time and 3 space of Minkowski spacetime. The extra dimensions are required for anomalies to cancel in the string theory math.
  4. Feb 28, 2005 #3
    Thanks for the clarification. I pretty much thought so.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook