Why is it that we're never observing this, for example, why is it the table doesn't diffract as we bring it through the door?

那么为什么我们,从来观察不到它呢，举个例子，搬动一个桌子穿过门,它为什么不衍射呢？

麻省理工公开课 - 化学原理课程节选

Let's call someting invisible not only it can't be seen, not only it can't be observed, but it can't be detected at all.

让我们把一些不仅是看不见的,不仅是观察不到的，而且是完全检测不到的，东西称为无形的。

耶鲁公开课 - 死亡课程节选

Two, different possibility, can't be observed.

第二个不同的解释，观察不到的。

耶鲁公开课 - 死亡课程节选