Now spin is normally discussed in terms of a dimensionless parameter

黑洞自旋在物界中一般用一个不带单位的参数来计。

This dependence is captured in a dimensionless number known as the Drag Coefficient.

这种依赖性以称为阻力系数的无纲数来体现。

Then you have “The Big Crunch”, which is space collapsing into a dimensionless singularity.

然后就是“大收缩” ，即空间坍缩成一个无纲的奇点。