geometry - Visualizing the 4th dimension. - Mathematics ...
https://math.stackexchange.com/questions/228618018.05.2017 · Your 4D space is just a set of 4-uplets ( x, y, z, t), and you can still project points ( x 0, y 0, z 0, t 0) in your surface onto "hyperplanes", such as the set defined by the equation t 0 = 0. For instance, the projection of a point ( x, y, z, t) on the hyperplane t = 0 is just ( x, y, z, 0).