然而，这些恐惧可能只是存在于我们的头脑中。

These fears could just be in our heads, however.

youdao

我们知道别人的大脑或书本里有什么知识，我们的头脑里有什么知识。

We know what knowledge lies in other brains or books, and what lies in our heads.

youdao

我们已经拥有世界上最强大的杠杆——我们的头脑。

We all have been given the most powerful lever on earth, our minds.

youdao

That was Cartesian space. When I plot r as a distance out from the nucleus that is sort of our simple-minded planetary model. Now let's look at energy.

笛卡尔坐标系，当我用r表示,离原子核的距离时，那只是我们头脑中简单的,类似行星的模型，现在我们看一下能量问题。

麻省理工公开课 - 固态化学导论课程节选