On the Effective Electron Mass in Magnetar-like Fields
  We show, either quantum mechanically or classically, that the variation of the effective mass induced in a charged particle by the presence of an ultra-strong electromagnetic field may lead to observable consequences. In particular, we discuss how this effect may operate on electrons close to the surface of a magnetar, a neutron star with a super-strong magnetic field of the order of $10^{11}$ Tesla. 
M. Conte and M. Palazzi (Dipartimento di Fisica, Universita' di Genova   and INFN Sezione di Genova), M. Pusterla and R. Tur...