We can create a Dirac equation with no potential energy and zero momentum and still get spin? Is this correct? How do the Pauli spin matrices apply here? On the surface, the Dirac equation seems fairly straightforward, but when you dig even a little deeper, it's starts to become unwieldy I've got a million questions, but my first one is what does the zero potential, zero momentum Dirac equation tell us about spin? I don't get it.