quantum physics
because it describes the behavior of particles and systems from fundamental principles without relying on empirical observations alone. Instead, it’s based on mathematical frameworks like quantum mechanics and quantum field theory. for example Schrodinger equation
classical mechanics
Classical mechanics is not typically referred to as an “ab initio” model in the same sense as quantum mechanics. it depends on empirical data also
classical electromagnetism
Classical electromagnetism, as described by Maxwell’s equations, is not typically considered an “ab initio” model in the same sense as some theories in quantum mechanics. The foundations of classical electromagnetism are grounded in experimental observations and empirical laws, including: