Relativistic particle in a three-dimensional box

Solution of Dirac eqn for a relativistic spin-1/2 particle in a 3-dim square box. ► Non-relativistic and ultra-relativistic limits are related to the size of the box. ► The density of states is shown to be a bit higher than the non-relativistic one. ► In ultra-relativistic limit density of states approaches the non-relativistic one.