In mathematics (and physics) a sequence of n numbers can be understood as a location in an n-dimensional space. When n=4, the set of all such locations is called the fourth dimension. Now, Mathematicians create videos that help in visualizing four-dimensional objects.
The 4th dimension may be interpreted either as time, or as a literal fourth dimension of space, a fourth spatial dimension. Rotating shadow of a tesseract rotating on a single axis and a single plane is fine example of 4th dimension.
Mathematicians, freed in their imaginations from physical constraints, can conjure up descriptions of objects in many more dimensions than that. Points in a plane can be described with pairs of numbers, and points in space can be described with triples. Why not quadruples, or quintuples, or more?
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