The four dimensional space, means that the mankind the substance space( namely three dimensional space ) of the concrete activity, plus one more consciousness measurement ( time factor).

四维空间，是指在人类具体活动的实质空间（即三维空间）之上，再加上一个瞬间取向的知觉量度（即时间因素）。

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On the next rung up the ladder of difficult mathematics comes doing the same thing in four-dimensional space.

在这个困难的数学阶梯上取得下一个进展之前，得先在四维空间做同样的事情。

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For those keen to know more: the computations involve "envisioning space and time as part of a four-dimensional crystal lattice, with discrete points spaced along columns and rows.

一点额外的话给那些想要知道更多的人：这个计算包括 “想象一下，时间和空间将成为水晶方格似的四维空间的一部分，不连续的点在空间纵横其间。”

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Now imagine this happening in the four-dimensional fabric of space and time.

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On the next rung up the ladder of difficult mathematics comes doing the same thing in four-dimensional space.

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Einstein's theory of relativity unified these and created a four-dimensional space that is an analogue to our three-dimensional space, except that the "distance" between two points need not be positive.

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