“Why do we call quantum physics an ab initio model? Ans – It’s because we went to the finest classification of matter, and we found mechanics that govern that realm we cannot go deeper that that realm and hence all the formulation in quantum mechanics are called ab initio models.
Why do we call classical mechanics an ab initio model? Ans – Classical world is the world we see and live in, so called low velocity world. Our everyday tasks are coming under classical mechanics be it movements or work. formulation of classical models is enough to explain the motion of everyday object.
Is classical electromagnetism is an ab initio model (and if it is one, what are its first principles)?” Ans – Yes, Classical electromagnetism is an ab initio model. Its first principle includes Coulomb’s law, Gauss law, Faraday’s law, Lorentz law and Maxwell’s equations.