Born-Infeld Non-linear Electrodynamics and String Theory

Born-Meld electrodynamics is the particular non-linear generalization of Maxwell electrodynamics. The well known remarkable features of the Born-Infeld electrodynamics include (i) its invariance under (Dirac) electric-magnetic duality, (ii) absence of dichroism, and (iii) existence of solitonic solutions. In addition, the Born-Infeld electrodynamics arises as the low-energy effective action of open strings, and as part of the world-volume effective action of D3-branes (string solitons). I describe an N = 1 supersymmetric generalization of the Born-Infeld action, and emphasize its physical interpretation as the Nambu-Goldstone-type action associated with spontaneous partial supersymmetry breaking, N = 2 to N 1, in a 4-dimensional spacetime.