“三维空间”是人们一直视为真理的一种概念，即在上下、左右、前后三条轴线上可以确定任一空间位置。爱因斯坦提出了“四维空间”说，将时间作为判断时空位置的第四条轴线。这一理论大概是如今“时空”概念大流行的依据所在。有科学家预言，随着人类认识能力的提高，今后或许 “Three-dimensional space” is a concept that people have always regarded as truth, that is, any spatial position can be determined on the three axes of up, down, left and right, front and back. Einstein proposed the “four-dimensional space” theory, using time as the fourth axis to judge the location of space-time. This theory is probably the basis for the current concept of “space-time”. Some scientists predict that with the improvement of human awareness, perhaps in the future