Thanks for the link, TIL. So given: > In 1926, Oskar Klein proposed that the fourth spatial dimension is curled up in a circle of a very small radius, so that

Thanks for the link, TIL. So given: > In 1926, Oskar Klein proposed that the fourth spatial dimension is curled up in a circle of a very small radius, so that a particle moving a short distance along that axis would return to where it began. The distance a particle can travel before reaching its initial position is said to be the size of the dimension. I've read many times that the shape of the universe could be a loop i.e if you traveled in one direction, over a long period you could possible loop to your starting point. From that pasted from Wikipedia, in a looped-shaped universe, would that be the size of the dimension of the universe you just traveled?