> But if you understand the math of quantum mechanics, and you understand how the experiments relate to the math, then you understand how quantum mechanics works. Its not actually that complicated, its just weird.
OK, but is that really understanding, or just an ability to crank the handle of the model and make a prediction? How should we interpret what is going on? What to make of observational wave function collapse, or long-distance quantum entanglement (which seems completely at odds with our understanding of space and time)?
I'm too much an instrumentalist to give you an unbiased answer.
My view is that, as it pertains to any theory, the ability to make reasonably accurate predictions within a given region, and reasonably accurately describe the region where those predictions are correct is understanding.
I don't believe our knowledge is complete, because the universe is effectively infinite, so there's room for effectively infinite combinations and permutations of phenomenon even within our understanding. But when we encounter something that contradicts our understanding, that doesn't mean we didn't understand anything we experienced before. It just means that our overall understanding was incomplete.
it's not black and white. we understand plenty! (eg. QED, semiconductors, lots of quantum optics, etc.) and then there are more murkier areas (strong forces, QCD, Higgs) and then there are the untamed beasts that eat their young and season it with Nobel laureates (fundamental questions, structure of the electron, SUSY, things beyond the standard model)
OK, but is that really understanding, or just an ability to crank the handle of the model and make a prediction? How should we interpret what is going on? What to make of observational wave function collapse, or long-distance quantum entanglement (which seems completely at odds with our understanding of space and time)?