The unseen dimension’s small size explains why humans, or even atoms, are unaware of it. Even so, it would yield electromagnetism. And gravity, already present in the four-dimensional world, would be united with that force.
http://feynman.physics.lsa.umich.edu/~mduff/talks/1998%20-%20The%20Theory%20Formerly%20Known%20as%20Strings.pdf
However, since the extra dimensions are compactified, we would not normally observe effects of the extra dimensions at scales larger than the compactification radius. Thus, when we measure gravity in only three spatial dimensions, we find it to be weak; we have not measured gravity in the entirety of the space that the field lines inhabit. These extra dimensions could be compactified at a length scale just below the length scales at which we have successfully measured.
https://www.physicsforums.com/showpost.php?p=205918&postcount=8
There is a transference of thinking here, when we loose sight of the reductionistic principals
When you see, you see brane world? Brane world is adifferent level of thinking Reductionistic implication soildfy in a three dimensianl world, while out there exists this whole new set of holographical realizations?
It's always bigger then the matter distinctions, and yet, if we were to implore this new level of thinking, what new elements would arise?
Such an avenue of predictions like Mendeleev elements, would allow such predictions in superstringtheory(?) to identify new possible structures? New crystals?
What arises out of the standard model? There must be certain determinations below Planck length? What lies beneath our current realizations?
http://wc0.worldcrossing.com/WebX?14@176.1bsDbAXdZgf.59@.1dde61c6