What we've learned from QFT

The more I contemplate in quantum field theory, the more I become convinced it is nothing but many body quantum mechanics in much less confusing words!

If you've ever tried thinking about the quantum mechanics, you've probably noticed how difficult it is to think in this context. The mathematical representation of theory ties up your hands so tightly that the simplest questions seem extremely intricate. My own experience of learning quantum mechanics was a mixture of what I saw in standard QM text books with quantum information theory. In spite of this, it took me almost three years to get over some of the stupid puzzles I had in the back of my mind as remnants of taking the formulation too literal. For instance, the way uncertainty principle is usually being presented in basic QM is terribly misleading and if you're that type of person who takes it too literal, it entirely messes up your mind!. That was actually what happened to me.

Nevertheless, once you resolved these problems for yourself, you tend to translate everything you see in QFT to QM before swallowing which is indeed really helpful. My status these days is having fun going back and forth between QFT and QM. Mostly, this is a pretty much straightforward procedure and as soon as you get the dictionary you can actually enjoy this little game. However sometimes it gets really tricky. If you don't believe me, here is an example: Renormalization Group flow. It'll probably take a bit of effort to find the subtle link but I'm quite sure you'll find it amusing.