%0 Journal Article %A Dobado González, Antonio %A López Maroto, Antonio %T Primordial torsion fields as an explanation of the anisotropy in cosmological electromagnetic propagation %D 1997 %@ 0217-7323 %U https://hdl.handle.net/20.500.14352/58728 %X In this letter we provide a simple explanation of the recent finding of anisotropy in electromagnetic (EM) propagation claimed by Nodland and Ralston. We consider, as a possible origin of such effect, the effective coupling between EM fields and some tiny background torsion field. The coupling is obtained after integrating out charged fermions, it is gauge-invariant and does not require the introduction of any new physics. %~