The Dirac equation as a quantum walk: higher dimensions, observational convergence

Understand

The Dirac equation can be modelled as a quantum walk, with the quantum walk being: discrete in time and space (i.e.

• a unitary evolution of the wave-function of a particle on a lattice); homogeneous (i.e.
• translation-invariant and time-independent), and causal (i.e.
• information propagates at a bounded speed, in a strict sense).