Dimension, also called dimension, is the number of independent parameters in mathematics. In physics and philosophy, the number of independent space-time coordinates. Dimension 0 is an infinitesimal point with no length. 1 dimension is an infinite straight line with only length. 2-D is a plane, which is an area composed of length and width (or partial curves).

Three dimensions are the volume formed by two dimensions plus height. Four dimensions are divided into four dimensions in time and space. People usually refer to the transfer of objects on the timeline. (There are just two kinds of four dimensions. 1. Four-dimensional space-time refers to three-dimensional space plus one-dimensional time. 2. Four-dimensional space only refers to four-dimensional space. ) Four-dimensional motion produces five dimensions.

Various theories:

According to the theory of relativity, space and time are inseparable, so the space-time that can be experienced is 4-dimensional, 3-dimensional is the space of experience, and 1 dimension is time.

However, due to the incompleteness of quantum mechanics and the incompatibility with relativity, physicists have also proposed various solutions. The most famous string theory holds that the space is 7, 10 or 1 1 dimension, but it has not been proved.