Professor Stephen Hawking, a famous British physicist, has this explanation: it is like a hair, which is a one-dimensional line from a distance. Under the magnifying glass, it is really three-dimensional; If we face time and space, if we have a magnifying glass with high magnification, we should also be able to reveal other possible 4-and 5-dimensional spaces, up to 1 1 dimensional space. So dimension refers to a perspective, not a fixed number; Judging, explaining, evaluating and determining a thing is a multi-faceted, multi-angle and multi-level condition and concept.