https://doi.org/10.1140/epjc/s10052-014-2899-y
Regular Article - Theoretical Physics
The photon magnetic moment problem revisited
1
Departamento de Física Teórica, Instituto de Cibernética, Matemática y Física, Calle E 309, Vedado, Havana, Cuba
2
ICTP, Strada Costiera 11, 34014 , Trieste, Italy
* e-mail: hugo@icimaf.cu
Received:
14
April
2014
Accepted:
12
May
2014
Published online:
7
June
2014
The photon magnetic moment for radiation propagating in magnetized vacuum is defined as a pseudotensor quantity, proportional to the external electromagnetic field tensor. After expanding the eigenvalues of the polarization operator in powers of 
, we obtain approximate dispersion equations (cubic in ), and analytic solutions for the photon magnetic moment, valid for low momentum and/or large magnetic field. The paramagnetic photon experiences a redshift, with opposite sign to the gravitational one, which differs for parallel and perpendicular polarizations. It is due to the drain of photon transverse momentum and energy by the external field. By defining an effective transverse momentum, the constancy of the speed of light orthogonal to the field is guaranteed. We conclude that the propagation of the photon non-parallel to the magnetic direction behaves as if there is a quantum compression of the vacuum or a warp of space-time in an amount depending on its angle with regard to the field.
© SIF and Springer-Verlag Berlin Heidelberg, 2014
