To model physics and not just a playground pretend version of it, you need to model the complete understanding of physics within the entire universe. We'd need answers to questions we're UNKNOWN-TIME away from understanding. This means modelling everything from the visual response of a human eye to the known-truths of the universe and beyond.

We can't even trust our own nose to smell bullshit but we're supposed to have a model for it.

Please think critically folks!