Hi, my level of knowledge of string theory is the following : I understand that to each elementary particle there corresponds a string vibrating at an associated frequency (mode). So my questions are : 1. Is there some table yet that proposes a correspondence? Such as : electron : so many Hz, tau neutrino : so many Hz, photon : so many Hz, and so on. 2. What determines the length of a string? 3. I don't buy the curled up dimensions yet. It seems to me that anything that is curled up can still be described with the known 3 dimensions. 4. As for time being a dimension, I'm rather at ease with time being nothing more that the number of rotations (or oscillations) an arbitrary reference body has made. Calling it a 4th (or 11th) dimension seems to me to be solely for mathematical purposes, and not sufficient to propose that we live in a pop-up book we all fail to properly visualize.