  The physical consequences of the relativistic and nonrelativistic approaches
to describe the energy levels of electrons which propagate in a static
homogeneous magnetic field are considered. It is shown that for a given
strength of the magnetic field, the quantized energy levels of the electrons
calculated by nonrelativistic and relativistic equations differ substantially,
up to few orders of magnitude for a magnetic field of about 1 Tesla.
Experimental verification to resolve the discrepancy would be very welcome.
