The Effect Of Birefringence Of The Vacuum

From 1934, Halpern recognized that virtual pair production in the vacuum gives rise to interactions between photons and the fact that in quantum electrodynamics two photons can interact through the creation of virtual electron-position pairs leads to additional terms in the Lagrangian density which is biquadratic in field intensities. It is shown in this note that this causes birefringence of the vacuum which behaves like a polarizable continuum. There are two modes of transmission and the two modes'polarizations are parallel and perpendicular to the plane respectively containing the external magnetic field and the wave propagation direction. Maxwellian electromagnetism as the mathematic description of the classical electromagnetic field has a basic hypothesis: the photon rest mass equals zero. However the hypothesis's correctness has gotten the attention all the time. And generally the theory of the vacuum birefringence is without regard for the mass of the photon,so we consider adding the mass of the photon to the effect of vacuum birefringence and calculating the influence of the photon mass on the vacuum birefringence.The study in this paper shows the basic theory process: the calculation method index of refraction. Although the photon mass will cause a change to the refractive indices n‖and n⊥of vacuum birefringence, the differenceΔn=n‖-n⊥is not changed. The emergent light's ellipticity of the polarized wave is unchanged too. Although some other methods have been used to detect the upper limits for the photon mass in classic electrodynamics, it is unfeasible to detect the upper limits for the photon mass according to the experiments of vacuum birefringence.