> Electromagnetic field changes are described by complex numbers. You can do this, but there's no need to. You can describe electromagnetism using only real nu

> Electromagnetic field changes are described by complex numbers. You can do this, but there's no need to. You can describe electromagnetism using only real numbers. A better argument for imaginary numbers being necessary to describe the universe is quantum mechanics, since quantum interference (in particular destructive interference) means that two possible events that each have a positive probability taken in isolation can cancel each other out, implying that probabilities can combine with a minus sign. And that means that probability amplitudes, which are square roots of probabilities, can have nonzero imaginary parts.