### The Large and Small Components of the Dirac Wavefunction

Returning to the pair of equations in and . Note that for , that is non-relativistic electrons, is much bigger than .

In the Hydrogen atom, would be of order times smaller, so we call the large component and the small component. When we include relativistic corrections for the fine structure of Hydrogen, we must consider the effect has on the normalization. Remember that the conserved current indicates that the normalization condition for the four component Dirac spinor is.

Jim Branson 2013-04-22