How I Learned to Stop Worrying and Love Uncertainty

Like most physicists, I spent much of my career ignoring the majority of quantum mechanics. I was taught the theory in graduate school and applied the mechanics here and there when an interesting problem required it … and that’s about it.

Despite its fearsome reputation, the mathematics of quantum theory is actually rather straightforward. Once you get used to the ins and outs, it’s simpler to solve a wide variety of problems in quantum mechanics than it is in, say, general relativity. And that ease of computation—and the confidence that goes along with wielding the theory—mask most of the deeper issues that hide below the surface.

Deeper issues like the fact that quantum mechanics doesn’t make any sense. Yes, it’s one of the most successful (if not the most successful) theories in all of science. And yes, a typical high school education will give you all the mathematical tools you need to introduce yourself to its inner workings. And yes, for over a century we have failed to come up with an alternative theory of the subatomic universe. Those are all true statements, and yet: Quantum mechanics doesn’t make any sense.

Instead of trying to make sense of the quantum world, let’s use the quantum world to make sense of ours.

The statements that quantum mechanics makes about the subatomic world fly in the face of our natural intuition about the macroscopic world. If I throw a ball at you, you have a decent shot of catching it because you know it will only take a single path. If we make plans for dinner, we don’t need to worry about what the Andromeda Galaxy is doing right now because it’s very far away and thus very unlikely to interfere with our plans. If you see someone walk through your doorway, then you can say with confidence that they did,