Geometrical aspects of light propagation in nonlinear electrodynamics - art. no. 045001

We analyze the propagation of light in the context of nonlinear electrodyna mics, as it occurs in modified QED vacua. We show that the corresponding ch aracteristic equation can be described in terms of a modification of the ef fective geometry of the underlying spacetime structure. We present the gene ral form for this effective geometry and exhibit some new consequences that result from such an approach.