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. --- translating... 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?