That's a very wrong statement. Pretty sure I could explain all the maths, all the physics, all the electronics, all the operating systems and all the user space of a single high level language operation, when I was a fresh graduate. Now, I have forgotten most of the physics and electronics, since the university was quite some time ago, but feel free to ask any decent student of an IT bachelor, they should be able to pretty much build the PC from scratch. Sure, modern processors and whatnot add a bunch of optimizations, but you seem to really overstate the complexity of the computer.