I know that in string theory it is believed that all of the smallest of particles are strings and that the difference between the particles is how the strings vibrate. Could it be possible though that instead of each particle being a string that it could be a warp in space time? Is it possible that the difference between particles is what directions the warps in space time face instead of the way the strings vibrate? Is it also possible that not only gravity but all forces are caused by a warp in a particular dimension? Could this be an alternative to strings?