Main Question or Discussion Point
I sometimes hear that some aspects of the macroscopic world are emergent. That is, some people believe that certain properties and laws (for example crystal structure, superconductivity, the conservation laws, Maxwell's equations, the laws of thermodynamics, the existence of momentum) could not even in principle be derived from a complete knowledge of the fundamental properties of matter and energy and the four fundamental forces operating according to QM and Relativity in space-time. Are such features really emergent? Or can all macroscopic features of the universe be in theory derived from fundamentals?