Theory: there is no 2D.
A 2D drawing has length and heighth, but if you take a 2D drawing and turn it sideways, there's always some sort of width, even if a millionth of a centimeter or greater, otherwise it wouldn't exist. We live in a 3D world and nothing can exist in our world as only 2D.
If you believe we live in a 4/D world (time being the 4th dimension) then in our current state we can never experience anything above or below our current dimension.
This is just a theory.. light is said to have no mass so there's always the possibility that there are other experiencable dimensions.
..
Theory on the 4 dimensions
So it's possible that while length width and height making up the 3 dimensions, exist in the artistic sense of design.. that the actual dimensionality make up of the universe could be more foundational and fundamental giving rise the the 3D construct we can observe
These 4 dimensions being:
-- Light
-- Frequency
-- Matter
-- And Time
....
Light being the massless 1st dimension
The 2nd being Frequency giving organisation to everything that exists (even effecting lights appearance and behavior)
Matter being the physical world
And Time being Entropy limiting the existence of the physical world
_______________________________
** This article is still in progress and being refined**