In fact the number of photons headed to your your eyes from those 2 tiles is exactly the same, physically that is the same.

实际上这两张瓷片,投射进你眼睛的光量子是一样的，从物理学的角度上说是完全相同的。

斯坦福公开课 - 7个颠覆你思想的演讲课程节选

So this is an example of Biomedical Engineering, one that is well integrated into our society to the point that we've probably all got a picture like this somewhere in our past, and where we understand the physical principles that allow us to use it.

故而,这成为生物医学工程的一个实例,这类技术已经很好的融入了我们的社会,因为也许我们每个人都拍过,这样的X光片,正是因为我们懂得了,相应的物理学原理才能去运用这项技术

耶鲁公开课 - 生物医学工程探索课程节选