Comment on 'Modified Coulomb Law in a Strongly Magnetized Vacuum'

摘要

In a recent Letter [1], Shabad and Usov studied the electric potential of a charge placed in a strong magnetic field B B_0 = m~2/e (m is the electron mass and e is its charge), as modified by the vacuum polarization. According to these authors, in the limit B → ∞ the modified potential becomes a Dirac delta function plus a regular background. With this potential they showed that the un-boundedness from below of the nonrelativistic hydrogen spectrum is removed. In this Comment, we point out that Shabad and Usov used an incorrect calculation to arrive at their otherwise correct result and conclusion.