the ab anitio way

Ab initio means starting from basic laws or first principles.

Quantum physics is called ab initio because we can start from the basic rules of quantum mechanics and calculate how a system behaves.

Classical mechanics can also be ab initio because it starts from basic laws like Newton’s laws of motion.

Classical electromagnetism can be considered ab initio too. Its main first principles are Maxwell’s equations. These describe how electric and magnetic fields behave and how they affect charged particles.