The mass limit of white dwarfs with strong magnetic fields in general relativity

Recently, U. Das and B. Mukhopadhyay proposed that the Chandrasekhar limit of a white dwarf could reach a new high level(2.58M) if a superstrong magnetic field were considered(Das U and Mukhopadhyay B 2013 Phys. Rev.Lett. 110 071102), where the structure of the strongly magnetized white dwarf(SMWD) is calculated in the framework of Newtonian theory(NT). As the SMWD has a far smaller size, in contrast with the usual expectation, we found that there is an obvious general relativistic effect(GRE) in the SMWD. For example, for the SMWD with a one Landau level system, the super-Chandrasekhar mass limit in general relativity(GR) is approximately 16.5% lower than that in NT.More interestingly, the maximal mass of the white dwarf will be first increased when the magnetic field strength keeps on increasing and reaches the maximal value M = 2.48 M with BD = 391.5. Then if we further increase the magnetic fields,surprisingly, the maximal mass of the white dwarf will decrease when one takes the GRE into account.